A new chromium-containing fluorination catalyst is described. The catalyst comprises an amount of zinc that promotes activity. The zinc is contained in aggregates which have a size across their largest dimension of up to 1 micron. The aggregates are distributed throughout at least the surface region of the catalyst and greater than 40 weight % of the aggregates contain a concentration of zinc that is within ±1 weight % of the modal concentration of zinc in those aggregates.

This invention relates to a chromium-containing fluorination catalyst and to a process for the production of fluorinated hydrocarbons that uses the catalyst. More particularly, the invention relates to a zinc promoted, chromium-containing fluorination catalyst and to process for the production of a fluorinated hydrocarbon in which a hydrocarbon or halogenated hydrocarbon is reacted with hydrogen fluoride in the presence of the catalyst.
The production of fluorinated hydrocarbons, which may also contain halogen atoms other than fluorine, by the catalysed vapour-phase fluorination of hydrocarbons or halogenated hydrocarbons with hydrogen fluoride is well known and numerous catalysts have been proposed for use in such processes. Catalysts containing and typically based on chromium, and in particular chromia, are frequently employed in the known processes. Thus, for example, chromia or a halogenated chromia may be used in the vapour-phase reaction of trichloroethylene with hydrogen fluoride to produce 1-chloro-2,2,2-trifluoroethane as described in GB-1,307,224 and in the vapour-phase reaction of 1-chloro-2,2,2-trifluoroethane with hydrogen fluoride to produce 1,1,1,2-tetrafluoroethane as described in CB-1,589,924. The same catalyst may also be used for the fluorination of chlorodifluoroethylene to 1-chloro-2,2,2-trifluoroethane, for example in a process for the removal of chlorodifluoroethylene impurity from 1,1,1,2-tetrafluoroethane as also described in GB-1,589,924.
EP-A-0502605 discloses a chromium-containing fluorination catalyst which comprises an activity-promoting amount of zinc or a compound of zinc. The catalyst can be used in a process for preparing 1,1,1,2-tetrafluoroethane in which 1-chloro-2,2,2-trifluoroethane is reacted with hydrogen fluoride in the presence of the catalyst to produce the 1,1,1,2-tetrafluoroethane. The 1-chloro-2,2,2-trifluoroethane may be prepared by reacting trichloroethylene with hydrogen fluoride in the presence of the same catalyst.
Manufacturers of fluorinated hydrocarbons are always seeking improved catalysts for use in the manufacture of those compounds. It has now been found that the stability of chromium-containing catalysts incorporating controlled amounts of zinc may be improved if the distribution of zinc in the catalyst meets certain criteria.
According to the present invention there is provided a chromium-containing fluorination catalyst which comprises an amount of zinc, said zinc being contained in aggregates which have a size across their largest dimension of up to 1 micron and which are distributed throughout at least the surface region of the catalyst and wherein greater than 40 weight % of the aggregates contain a concentration of zinc that is within ±1 weight % of the modal concentration of zinc in those aggregates.
The present invention also provides a process for the production of fluorinated hydrocarbons which comprises reacting a hydrocarbon or a halogenated hydrocarbon with hydrogen fluoride in the vapour phase in the presence of a fluorination catalyst as herein defined.
The zinc in the chromium-containing fluorination catalysts of the present invention is contained in aggregates that are evenly distributed throughout at least the surface region of the catalyst. By the surface region of the catalyst, we are intending to refer to that portion of the catalyst that will contact the hydrogen fluoride and organic reactants during use. The surface of a catalyst is generally that region where the coordination or valency of the atoms is not satisfied when compared to the bulk material. Preferably, the zinc-containing aggregates are evenly distributed throughout the entire catalyst bulk. The aggregates have a size across their largest dimension of up to 1 micron (1 μm), preferably in the range of from 20 nm to 1 μm, and greater than 40 weight %, preferably greater than 50 weight %, more preferably greater than 60 weight % and especially greater 70 weight % of the aggregates contain. a concentration of zinc that is within ±1 weight % of the modal concentration of zinc in those aggregates. In a preferred embodiment, greater than 80 weight %, more preferably greater than 85 weight %, and especially greater than 90 weight % of the aggregates contain a concentration of zinc that is within ±2 weight % of the modal concentration of zinc in those aggregates.
The modal concentration of zinc in the aggregates is that concentration of zinc that occurs most frequently in the aggregates expressed as a whole number.
By 'evenly distributed' we include 'substantially evenly distributed' and mean that the number or density of zinc-containing aggregates in each region of the catalyst surface or the catalyst bulk, where the zinc is dispersed throughout the entire catalyst, is substantially the same. For example, where the aggregates are only present at the catalyst surface, the number of aggregates in each square millimetre of the catalyst surface is within ±2% of the mean number of aggregates per square millimetre of the catalyst surface. Where the zinc-containing aggregates are distributed throughout the entire catalyst bulk, the number of aggregates in each square millimetre of the catalyst bulk is within ±2% of the mean number of aggregates per square millimetre of the catalyst bulk.
In a preferred embodiment, the chromium-containing fluorination catalysts of the invention comprise one or more compounds selected from the chromium oxides, the chromium fluorides, fluorinated chromium oxides and the chromium oxyfluorides.
The chromium compounds which make up the chromium-containing catalyst of the invention can contain chromium in any of its usual oxidation states, namely chromium (II), chromium (III) and chromium (VI). However, the bulk or perhaps all of the chromium compounds in the catalysts will usually be based on chromium (III), although in a preferred embodiment from 0.1 to 8.0% by weight of the chromium based on the total weight of chromium in the catalyst will be present as chromium (VI). The performance, particularly the activity and stability, of zinc promoted chromium-containing catalysts can be improved if some of the chromium in the catalyst is present as chromium (VI)
Chromium (III) may typically comprise from 92.0 to 100% by weight, preferably from 94.0 to 100% by weight and particularly from 96.0 to 100% by weight of the total weight of chromium in the catalyst. Where chromium (VI) is also present, the catalyst of the invention typically comprises from 92.0 to 99.9% by weight, preferably from 94.0 to 99.9% by weight, e.g. from 95.0 to 99.5% by weight, particularly from 96.0 to 99.5% by weight and especially from 96.0 to 99.0% by weight, e.g. from 98.0 to 99.0% by weight of chromium (III) and from 0.1 to 8.0% by weight, preferably from 0.1 to 6.0% by weight, e.g. from 0.5 to 5.0% by weight, particularly from 0.5 to 4.0% by weight and especially from 1.0 to 4.0% by weight, e.g. from 1.0 to 2.0% by weight of chromium (VI) based on the total weight of chromium in the catalyst. As all the chromium is usually present as chromium compounds, the percentages quoted above will also normally define the amounts of chromium (III) and chromium (VI) compounds in the catalyst based on the total weight of chromium compounds.
Chromium (III) compounds that may be present in the chromium-containing catalyst of the invention include compounds selected from the group consisting of chromium (III) hydroxide, chromia (i.e. chromium (III) oxide), chromium (III) fluoride, fluorinated chromia and chromium (III) oxyfluorides. Chromium (VI) compounds that may be present in the catalyst include compounds selected from the group consisting of chromium (VI) oxide, chromic acid, fluorinated chromium (VI) oxide, chromium (VI) oxyfluorides and chromyl fluoride. The catalyst preferably contains one or more chromium (III) compounds and one or more chromium (VI) compounds selected from the above groups of compounds. The precise constitution of the catalyst will depend, inter alia, on the methods used for its preparation and whether the composition of the catalyst is measured pre- or post-fluorination.
Before the catalyst of the present invention is used in a fluorination process or before it is subjected to a fluorination pre-treatment, a significant proportion of the chromium, e.g. in excess of 50.0 weight % and more typically in excess of 75.0 weight % based on the total weight of chromium in the catalyst, is preferably present in the catalyst as chromium oxides, including chromia and preferably chromium (VIII) oxide. It may also contain an amount of chromium hydroxides, including chromium (III) hydroxide and perhaps chromium (VI) hydroxide. The amounts of the chromium (III) oxides and hydroxides combined and, when present, the amounts of the chromium (VI) oxides and hydroxides combined are preferably as discussed above, for the chromium (III) and chromium (VI) compounds generally. A preferred chromium-containing catalyst, pre-fluorination, has a molar ratio of chromium (III) to oxygen to hydroxyl species (Cr (III):O:OH) in the range of from 1:0.5:2 to 1:1.5:0, preferably in the range of from 1:1:1 to 1:1.5:0. This ratio can be readily determined using thermogravimetric analysis. In one particular embodiment, the chromium-containing catalyst, pre-fluorination, has a molar ratio of chromium (III) to oxygen to hydroxyl species (Cr (III):O:OH) in the range of from 1:0.3:2 to 1:n:m, preferably in the range of from 1:1:1 to 1:n:m, where n is less than 1.5, m is greater than zero and 2n+m=3.0.
When the catalyst is used in a fluorination process, or when it is subjected to a fluorination pre-treatment to be described hereinafter, a proportion of the chromium oxides in the catalyst and any chromium hydroxides that may be present will be converted to chromium fluorides, fluorinated chromium oxides and/or chromium oxyfluorides.
The zinc/chromic catalysts used in the present invention may be amorphous. By this we mean that the catalyst does not demonstrate substantial crystalline characteristics when analysed, for example, by X-ray diffraction.
Alternatively, the catalysts may be partially crystalline. By this we mean that from 0.1 to 50% by weight of the catalyst is in the form of one or more crystalline compounds of chromium and/or one or more crystalline compounds of zinc. If a partially crystalline catalyst is used, it preferably contains from 0.2 to 25% by weight, more preferably from 0.3 to 10% by weight, and particularly from 0.4 to 5% by weight of one or more crystalline compounds of chromium and/or one or more crystalline compounds of zinc.
The amount of crystalline material in the catalysts of the invention can be determined by any suitable method known in the art. Suitable methods include X-ray diffraction (XRD). When XRD diffraction is used, the amount of crystalline material, such as the amount of crystalline chromium oxide, can be determined with reference to a known amount of graphite present in the catalyst (e.g. graphite used in producing catalyst pellets) or, more preferably, by comparison of the intensity of the XRD patterns of the sample materials with reference materials prepared by suitable internationally recognised bodies, for example NIST (National institute of Standards and Technology), that contain a known amount of a crystalline material.
The zinc is usually present in the catalyst as a zinc compound and may be present in or on the chromium-containing catalyst, that is the zinc or zinc compound may be incorporated in the chromium-containing catalyst or it may be supported on the surface of the catalyst, depending at least to some extent upon the particular method employed for preparing the catalyst. If the zinc is incorporated throughout the chromium-containing catalyst, as is preferred, then it should be substantially evenly distributed throughout the catalyst bulk.
The zinc is typically present in the catalyst in an amount of from 0.5 to 25% by weight based on the total weight of the catalyst. The amount of zinc is important, because at the right levels it will promote the activity of the chromium-containing catalyst. Too much zinc, on the other hand, may result in a decrease rather than an increase in catalyst activity.
The amount of zinc which will promote catalyst activity and produce a catalyst having an activity that is greater than the chromium-containing catalyst alone depends, at least to some extent, on the surface area of the catalyst and whether the zinc is incorporated throughout the catalyst bulk or just supported on its surface. Generally, the larger the working surface area of the catalyst, the greater is the amount of zinc which will be required to promote catalyst activity. Furthermore, catalysts containing zinc incorporated throughout their bulk, i.e. at surface and non-surface locations, will tend to require larger amounts of zinc than those catalysts which only have zinc on their surface.
By way of example, in the case of a catalyst where the zinc is introduced by impregnation to reside predominantly at the catalyst surface, activity promoting amounts of zinc for a chromium-containing catalyst having a working surface area of between 20 and 50 m2/g are usually in the range of from about 0.5% to about 6.0% by weight based on the total weight of the catalyst, preferably in the range of from about 1.0% to about 5.0% by weight and especially in the range of from about 2.0% to about 4.0% by weight.
However, for catalysts having larger working surface areas, for example greater than 100 m2/g, and comprising zinc distributed throughout the catalyst bulk, the zinc may be present in an amount of from 5.0% to 25.0% by weight based on the total weight of the catalyst, preferably in an amount of from 5.0 to 20.0% by weight and especially in an amount of from 5.0 to 10.0% by weight.
For catalysts having small working surface areas, i.e. less than 20 m2/g, for example about 5 m2/g, the amount of zinc may be as low as 0.5% to 1% by weight based on the total weight of the catalyst.
It should be understood that the amounts of zinc discussed above refer to the amount of zinc itself, whether present as elemental zinc or as a compound of zinc. Thus, where the zinc is present as a compound of zinc, as is usual, the amounts refer to the zinc provided by the zinc compound and not to the amount of the compound of zinc.
Preferred catalysts of the invention have a surface area in the range of from 20.0 to 300.0 m2/g, more preferably in the range of from 100 to 250 m2/g and particularly in the range of from 180 to 220 m2/g. When referring to the surface area of the catalyst, we are referring to the surface area prior to any fluorination treatment when measured by BET nitrogen isotherm (see, for example, G C Bond, Heterogeneous Catalysis—Principles and Applications 1987). These catalysts preferably comprise from 0.5 to 25.0% by weight, more preferably from 0.5 to 10.0% by weight and particularly from 1.0 to 6.0% by weight of zinc based on the total weight of the catalyst. The zinc can be distributed throughout the catalyst at surface and non-surface locations or just at the surface.
Although the amount of zinc which will promote catalyst activity will vary depending, inter alia, on the surface area of the catalyst, upon the distribution of zinc in the catalyst and upon the method that is used to prepare the catalyst, for any particular catalyst and catalyst preparation method, the amount of zinc that will promote catalyst activity is readily determined by routine experimentation using the above percentages as a guide.
The chromium-containing catalyst may also comprise metal oxides, fluorinated metal oxides, metal fluorides or metal oxyfluorides other than chromium oxides, fluorinated chromium oxides, chromium fluorides or chromium oxyfluorides. The additional metal oxide may, for example, be selected from alumina, magnesia and zirconia, and in particular magnesia and alumina, which during operation of the catalyst may be converted at least in part to aluminium fluoride and magnesium fluoride respectively.
If desired, the catalyst may also contain one or more metals other than zinc, for example nickel, cobalt or other divalent metals. Preferably, however, the chromium-containing catalyst will comprise just zinc, either as a metal but more typically as one or more zinc compounds.
The chromium-containing catalyst of the invention may also be supported on a catalyst support material such as activated carbon or alumina.
The zinc promoter may be introduced into and/or onto the chromium-containing catalyst or the form of compound, for example a halide, oxyhalide, oxide or hydroxide, depending at least to some extent upon the catalyst preparation technique employed. When the zinc promoter is introduced by impregnating a chromium-containing catalyst, e.g. one containing one or more chromium (III) compounds and optionally one or more chromium (VI) compounds, with a zinc compound, the zinc compound is preferably a water-soluble salt, for example a halide, nitrate or carbonate, and is impregnated into the chromium-containing catalyst by contacting the catalyst with an aqueous solution or slurry of the zinc compound.
In an alternative method for preparing the catalyst of the invention, the hydroxides of zinc and chromium are co-precipitated and then converted to their oxides by calcination to prepare a mixed oxide catalyst.
If other metal oxides are to be included in the catalyst, such as alumina, then these can be introduced by co-precipitating the hydroxides of chromium and the other metal and then converting the hydroxides to their oxides by calcination to prepare a mixed oxide catalyst, e.g. of chromium and aluminium oxides such as chromic and alumina. Zinc can be introduced into the catalyst by impregnating the hydroxide, or oxide mixture with an aqueous solution or dispersion of a zinc compound in the manner discussed above. Alternatively, zinc hydroxide can be co-precipitated with the hydroxides of chromium and the other metal and the three hydroxides then converted simultaneously to their oxides by calcination.
In a preferred embodiment, the catalysts of the present invention are prepared by adding zinc and chromium (III) salts to water and then co-precipitating the hydroxides of zinc and chromium (III) by adding a suitable inorganic hydroxide and preferably ammonium hydroxide to the aqueous salt solution. The co-precipitation is conducted under mixing conditions that will result in the zinc being evenly distributed throughout the catalyst. The mixture of zinc and chromium hydroxides is then collected, e.g. by filtration, washed and calcined to convert the hydroxides to their oxides. Any water soluble and stable salts of zinc and chromium can be used including the chlorides, carbonates and nitrates. Preferred salts of chromium include chromium nitrate and basic chromium nitrate (Cr(NO3)2.OH). A particularly suitable chromium salt is chromium (III) nitrate. A preferred zinc salt is zinc nitrate.
The washing process following collection of the mixed hydroxide precipitate can be important, because if the precipitate is prepared from a solution containing a nitrate salt then any nitrate that remains following the washing process can act as an oxidant to generate chromium (VI) from chromium (III) during the calcination process. The presence of a small amount of chromium (VI) in the catalyst can further improve catalyst activity and stability. More thorough washing of the collected precipitate, e.g. by repeated washing using fresh batches of washing liquor, will tend to reduce the residual nitrate levels and hence the amount of nitrate that is available to oxidise the chromium (III) during the calcination step. Furthermore, the nature of the washing medium can influence the efficacy with which nitrate contained in the mixed hydroxide precipitate is removed. For example, washing with an aqueous ammonia solution is more effective at removing the nitrate than water alone. Thus, if the mixed hydroxide precipitate is prepared from an aqueous solution containing chromium (III) and/or zinc nitrate, it is possible to control the level of chromium (VI) in the catalyst following calcination by exercising control over the washing process, which in turn will affect the residual level of nitrate, in the precipitate that is available to oxidise the chromium (III).
Where a calcination step is employed in the production of the catalysts of the invention, as is preferred, it typically involves heating the precursor catalyst material at a tens in the range of from 300 to 150° C., more preferably in the range of from 300 to 400° C., for example around 30° C. The calcination may be conducted in an inert atmosphere, e.g. of nitrogen, or it may be conducted in air or in an atmosphere comprising air or oxygen in mixture with an inert gas such as nitrogen.
The calcination temperature that is used can also influence the level of chromium (VI) in the final catalyst. For example, if the catalyst is prepared by calcining a mixed hydroxide precipitate prepared from an aqueous solution containing chromium (III) and/or zinc nitrate, then for a given level of residual nitrate following washing, higher calcination temperatures will tend to result in more of the chromium (III) being oxidised to chromium (VI).
Another convenient way of generating a desired level of chromium (VI) compounds in the catalyst is by introducing a controlled amount of air into the calcination step to oxidise the requisite proportion of chromium (III) to chromium (VI). Here again, the calcination temperature that is used can also influence the level of chromium (VI) in the final catalyst, with higher calcination temperatures tending to encourage greater oxidation of the chromium (III) for a given level of air.
The fluorination catalyst will usually be subjected to a fluorination treatment by heating in the presence of hydrogen fluoride, and optionally an inert diluent, prior to being used in the catalysis of fluorination reactions. A typical fluorination treatment comprises heating the catalyst in the presence of hydrogen fluoride at a temperature in the range of from 250 to 450° C., more preferably in the range of from 300 to 380° C. and particularly in the range of from 350 to 380° C. In a preferred embodiment, the fluorination treatment is conducted by contacting the fluorination catalyst with a mixture of hydrogen fluoride and nitrogen. Conveniently, the treatment is conducted in the reactor in which the subsequent fluorination process is to be conducted by passing the hydrogen fluoride or hydrogen fluoride/nitrogen mixture through the reactor while it is heated.
Following the fluorination treatment, the working catalyst usually comprises at least a proportion of zinc fluoride in and/or on a fluorinated chromium-containing catalyst material comprising one or more fluorine-containing chromium (III) compounds and preferably a small amount of one or more fluorine-containing chromium (VI) compounds selected from the fluorinated chromium oxides, the chromium fluorides and the chromium oxyfluorides. Where the catalyst is a mixed oxide catalyst prepared by co-precipitation of chromium and zinc hydroxides followed by calcination to convert the hydroxides to their oxides, as is preferred, the fluorination treatment usually converts at least a proportion of the oxides to oxyfluorides and fluorides.
The catalyst may be in the form of pellets or granules of appropriate shape and size for use in a fixed bed or a fluidised bed. Conveniently the catalyst is in the form of cylindrically shaped pellets having a length and diameter in the range of from 1 to 6 mm, preferably in the range of from 2 to 4 mm, for example 3 mm.
After a period of use catalysing a fluorination reaction, the used catalyst may be regenerated or reactivated, for example by heating in air/nitrogen or air/hydrogen fluoride mixtures at a temperature of from about 300° C. to about 500° C. The regeneration or reactivation may be conducted periodically until the catalyst has reached the end of its useful lifetime. The catalyst may also be regenerated by passing chlorine through the reactor while heating the catalyst. Alternatively, the catalyst may be regenerated continuously while the process is being operated.
A further aspect of the present invention resides in the use of the zinc-promoted, chromium-containing catalyst in a fluorination process in which a hydrocarbon or halogenated hydrocarbon is reacted with hydrogen fluoride in the vapour-phase at elevated temperatures.
Accordingly, the present invention also provides a process for the production of fluorinated hydrocarbons which comprises reacting a hydrocarbon or a halogenated hydrocarbon with hydrogen fluoride at elevated temperature in the vapour phase in the presence of a fluorination catalyst as herein defined.
Alkenes and alkanes as well as their halogenated counterparts containing at least one chlorine atom may be fluorinated using hydrogen fluoride and the catalysts of the present invention. Examples of specific vapour phase fluorinations which may be effected are the production of 1,1,1,2-tetrafluoroethane from 1-chloro-2,2,2-trifluoroethane, the production of 1-chloro-2,2,2-trifluoroethane from trichloroethylene, the production of pentafluoroethane from dichlorotrifluoroethane, the production of dichlorotrifluoroethane, chlorotetrafluoroethane and/or pentafluoroethane from perchloroethylene and the conversion of 1-chloro-2,2-difluoroethylene to 1-chloro-2,2,2-trifluoroethane.
The fluorination conditions employed when reacting the hydrocarbon or halogenated hydrocarbon with hydrogen fluoride in the presence of the catalyst of the invention may be those known in the art for fluorination reactions that employ chromium-containing catalysts, for example atmospheric or super-atmospheric pressures and reactor temperatures in the range of from 180° C. to about 500° C. When referring to the reactor temperature, we are referring to the mean temperature within the catalyst bed. It will be appreciated that for an exothermic reaction, the inlet temperature will be lower than the mean temperature, and for an endothermic reaction, the inlet temperature will be greater than the mean. The precise conditions will depend, of course, upon the particular fluorination reaction being carried out.
In a preferred embodiment, the catalyst of the invention is used in a process for preparing 1,1,1,2-tetrafluoroethane which comprises reacting 1-chloro-2,2,2-trifluoroethane with hydrogen fluoride in the vapour phase at elevated temperatures in the presence of the catalyst. Reaction temperatures in the range of from 250 to 500° C. are typically employed, with reaction temperatures in the range of from 280 to 400° C. being preferred and reaction temperatures in the range of from 300 to 350° C. being especially preferred. The process may be carried out under atmospheric or super-atmospheric pressures. Pressures of from 0 to 30 barg are preferred whilst pressures of from 10 to 20 barg are especially preferred.
In a further preferred embodiment, the catalyst of the invention is used in a multi-step process for preparing 1,1,1,2-tetrafluoroethane which comprises reacting trichloroethylene with hydrogen fluoride in the presence of the catalyst to form 1-chloro-2,2,2-trifluoroethane. The 1-chloro-2,2,2-trifluoroethane is then reacted with further hydrogen fluoride in the presence of the catalyst to form the 1,1,1,2-tetrafluoroethane. The conversion of trichloroethylene to 1-chloro-2,2,2-trifluoroethane and the conversion of 1-chloro-2,2,2-trifluoroethane to 1,1,1,2-tetrafluoroethane may be conducted in discrete reaction zones of a single reactor, but they are preferably conducted in different reactors. Both reactions are conducted at elevated temperatures in the vapour phase.
The preferred pressure and temperature conditions for the conversion of 1-chloro-2,2,2-trifluoroethane to 1,1,1,2-tetrafluoroethane are as specified above.
For the conversion of trichloroethylene to 1-chloro-2,2,2-trifluoroethane, the process is typically conducted at a temperature in the range of from 180 to 300° C., preferably in the range of from 200 to 280° C. and particularly in the range of from 220 to 260° C. Atmospheric or super-atmospheric pressures may be employed in the process. Typically, the process is conducted at a pressure in the range of from 0 to 30 barg, preferably in the range of from 10 to 20 barg.
A particularly preferred embodiment of the above-described multi-step process for preparing 1,1,1,2-tetrafluoroethane from trichloroethylene comprises the steps of:
(A) in a first reaction zone reacting 1-chloro-2,2,2-trifluoroethane with hydrogen fluoride in the vapour phase in the presence of a fluorination catalyst of the invention at a temperature of from 250 to 450° C. so tetrafluoroethane and hydrogen chloride together with unreacted starting materials;
(B) conveying the total product mixture of step (A) as well as trichloroethylene and optionally further hydrogen fluoride to a second reaction zone containing a fluorination catalyst of the invention and in said second reaction zone reacting the trichloroethylene with hydrogen fluoride in the vapour phase at 180 to 350° C. to form 1-chloro-2,2,2-trifluoroethane;
(C) collecting from step (B) a product mixture comprising 1-chloro-2,2,2-trifluoroethane, 1,1,1,2-tetrafluoroethane and hydrogen chloride;
(D) treating the product of step (C) to recover 1,1,1,2-tetrafluoroethane and produce a composition comprising 1-chloro-2,2,2-trifluoroethane that is suitable for conveying to the first reaction zone in step (A);
(E) conveying the 1-choro-2,2,2-trifluoroethane composition obtained from step (D) optionally together with further hydrogen fluoride to said first reaction zone; and
(F) collecting 1,1,1,2-tetrafluoroethane recovered in step (D).
Although the process described above, refers to first and second reaction zones, this should not be taken as limiting the process to a particular order. In chemical terms, trichloroethylene is first converted to 1-chloro-2,2,2-trifluoroethane and the 1-chloro-2,2,2-trifluoroethane is then subsequently converted to 1,1,1,2-tetrafluoroethane. Thus, the first reaction in the reaction sequence is the hydrofluorination of trichloroethylene to form 1-chloro-2,2,2-trifluoroethane.
The first and second reaction zones may be provided by first and second reactors or they may be discrete zones of a single reactor. Preferably, the first and second reaction zones are provided by first and second reactors.
At least the stoichiometric amount of hydrogen fluoride is usually employed in step (A) of the above process. Typically, from 1 to 10 moles of hydrogen fluoride and preferably from 1 to 6 moles of hydrogen fluoride are used per mole of 1-chloro-2,2,2-trifluoroethane. Accordingly, the product mixture of step (A) will usually contain unreacted hydrogen fluoride in addition to 1,1,1,2-tetrafluoroethane, hydrogen chloride and by-products. It may also contain unreacted 1-chloro-2,2,2-trifluoroethane. Preferred reaction temperatures for step (A) are in the range of from 250 to 500° C., more preferably in the range of from 280 to 400° C. and particularly in the range of from 300 to 350° C. Preferred reaction pressures for step (A) are in the range of from 0 to 30 barg, more preferably in the range of from 10 to 20 barg, for example around 15 barg. Preferred residence times in the first reaction zone are in the range of from 1 to 600 seconds, more preferably in the range of from 1 to 300 seconds and particularly in the range of from 1 to 100 seconds.
In step (B), usually from 10 to 50 moles of hydrogen fluoride and preferably from 12 to 30 moles of hydrogen fluoride per mole of trichloroethylene are employed. Again, the reaction product of this stage will normally contain unreacted hydrogen fluoride and may also contain unreacted trichloroethylene. Preferred reaction temperatures for step (B) are in the range of from 180 to 300° C., more preferably in the range of from 200 to 300° C. and particularly in the range of from 220 to 280° C. Preferred reaction pressures for step (B) are in the range of from 0 to 30 barg, more preferably in the range of from 10 to 20 barg, for example around 15 barg. Preferred residence times in the first reaction zone are in the range of from 1 to 600 seconds, more preferably in the range of from 1 to 300 seconds and particularly in the range of from 1 to 100 seconds.
Although the reactant mixtures that are conveyed to the first and second reaction zones must include hydrogen fluoride, this does not mean that a fresh or virgin supply of material has to be delivered to both reaction zones. For example, the process can be operated so that virgin hydrogen fluoride is only introduced into the second reaction zone in sufficient excess that enough unreacted hydrogen fluoride can be recovered from the product mixture exiting step (B) to drive the hydrofluorination reaction that occurs in the first reaction zone in step (A). One possibility is to operate step (D) of the process so that the 1-chloro-2,2,2-trifluoroethane composition that is collected also contains hydrogen fluoride in a sufficient quantity for the reaction in the first reaction zone. Alternatively, the process can be operated so that virgin hydrogen fluoride is only introduced into the first reaction zone in sufficient excess that enough hydrogen fluoride remains in the product mixture of step (A) that is conveyed to the second reaction zone for reaction with the trichloroethylene. Additionally, after start up, the hydrogen fluoride required for the hydrofluorination reactions in the first and second reaction zones could even be introduced into a distillation column used to conduct step (D) of the process.
The reaction and separation steps which make up the preferred multi-step process for making 1,1,1,2-tetrafluoroethane may be performed using conventional equipment and techniques. Step (D), which is effectively a separation/purification step in which the useable components making up the product collected from step (B) are substantially separated from one another, may be effected by conventional distillation, phase separation and washing/scrubbing processes known to those skilled in the art.
The operation of the preferred multi-step process for making 1,1,1,2-tetrafluoroethane is described more particularly in EP-A-0449617.
In another preferred embodiment, the catalyst of the invention is used in a process for preparing pentafluoroethane which comprises reacting dichlorotrifluoroethane with hydrogen fluoride in the vapour phase at elevated temperatures in the presence of the catalyst. Reaction temperatures of at least 280° C., e.g. in the range of from 280 to 400° C., are typically employed, with reaction temperatures in the range of from 280 to 380° C. being preferred and reaction temperatures in the range of from 300 to 360° C. being especially preferred. The process may be carried out under atmospheric or super-atmospheric pressures. Typically, the process is conducted at a pressure of from 0 to 30 barg, preferably at a pressure of from 12 to 22 barg and more preferably at a pressure of from 14 to 20 barg.
In yet another preferred embodiment, the catalyst of the invention is used in a multi-step process for preparing pentafluoroethane which comprises reacting perchloroethylene with hydrogen fluoride in the presence of the catalyst to form dichlorotrifluoroethane. The dichlorotrifluoroethane is then reacted with further hydrogen fluoride in the presence of the catalyst to form the pentafluoroethane. The conversion of perchloroethylene to dichlorotrifluoroethane and the conversion of dichlorotrifluoroethane to pentafluoroethane may be conducted in discrete reaction zones of a single reactor, but they are preferably conducted in different reactors. Both reactions are conducted at elevated temperatures in the vapour phase.
The preferred pressure and temperature conditions for the conversion of dichlorotrifluoroethane to pentafluoroethane are as specified above.
For the conversion of perchloroethylene to dichlorotrifluoroethane, the process is typically conducted at a temperature in the range of from 200 to 350° C., preferably in the range of from 230 to 330° C. and particularly in the range of from 240 to 310° C. Atmospheric or super-atmospheric pressures may be employed in the process. Typically, the process conducted at a pressure in the range of from 0 to 30 barg, preferably at a pressure in the range of from 10 to 20 barg and more preferably at a pressure in the range of from 12 to 18 barg.
A particularly preferred embodiment of the above-described multi-step process for preparing pentafluoroethane from perchloroethylene comprises the steps of:
(A) in a first reactor or a first plurality of reactors reacting perchloroethylene with hydrogen fluoride in the vapour phase at a temperature of from 200 to 350° C. in the presence of a chromium-containing fluorination catalyst of the invention to produce a composition comprising dichlorotrifluoroethane, hydrogen chloride, unreacted hydrogen fluoride and perchloroethylene, less than 2 weight % of chlorotetrafluoroethane and pentafluoroethane combined and less than 5 weight % of compounds having the formula C2Cl6-xFx, where x is an integer of from 0 to 6, based on the total weight of organic compounds in the composition;
(B) subjecting the composition from step (A) to a separation step to yield a purified composition comprising at least 95 weight % of dichlorotrifluoroethane and less than 0.5 weight % of compounds having the formula C2Cl6-xFx, where x is an integer of from 0 to 6, based on the total weight of organic compounds in the composition; and
(C) in a second reactor or a second plurality of reactors reacting the composition from step (B) with hydrogen fluoride in the vapour phase at a temperature of at least 280° C. in the presence of a chromium-containing fluorination catalyst of the invention to produce a composition comprising pentafluoroethane and less than 0.5 weight % of chloropentafluoroethane, based on the total weight of organic compounds in the composition.
By compounds of formula C2Cl6-xFx, where x is from 0 to 6, we include trichlorotrifluoroethane and dichlorotetrafluoroethane.
In step (A), from 3 to 50 moles of hydrogen fluoride are usually employed per mole of perchloroethylene. Preferably, from 4 to 20 moles of hydrogen fluoride and more preferably from 4 to 10 moles of hydrogen fluoride are used per mole of perchloroethylene. Preferred reaction temperatures and pressures for step (A) are as discussed above for the conversion of perchloroethylene to dichlorotrifluoroethane. Preferred residence times for the reactants in the first reactor in step (A) are in the range of from 10 to 200 seconds, more preferably in the range of from 30 to 150 seconds and particularly in the range of from 60 to 100 seconds.
In step (C), from 2 to 20 moles of hydrogen fluoride are usually employed per mole of dichlorotrifluoroethane. Preferably, from 2 to 10 moles of hydrogen fluoride and more preferably from 2 to 6 moles of hydrogen fluoride are used per mole of dichlorotrifluoroethane. Preferred reaction temperatures and pressures for step (C) are as discussed above for the conversion of dichlorotrifluoroethane to pentafluoroethane. Preferred residence times for the reactants in the second reactor in step (C) are in the range of from 10 to 200 seconds, more preferably in the range of from 20 to 100 seconds and particularly in the range of from 30 to 60 seconds.
The reaction and separation steps which make up the preferred multi-step process for making pentafluoroethane may be performed using conventional equipment and techniques. Separation step (B) may, for example, be effected using conventional distillation, phase separation and washing/scrubbing processes known to those skilled in the art.
The operation of the preferred multi-step process for making pentafluoroethane is described more particularly in WO 2007/068962.
It is preferred to operate processes that use the catalyst of the invention continuously, except for any shut-down time that is necessary to regenerate or reactivate a catalyst that has been deactivated though use. The feeding of air to the catalyst during operation of the process may counter catalyst deactivation and reduce the frequency of process shut-downs for catalyst regeneration.
The present invention is now illustrated but not limited by the following examples.

This patent is subject to a terminal disclaimer.


An extract of passion fruit is prepared. The extract has the effect of lowering blood pressure and serum nitric oxide levels in mammals. The extract also provides a hepatoprotective effect, as well as antioxidant and anti-inflammatory effects in mammals. A novel compound was identified in the extract and given the name edulilic acid.

The invention relates generally to botanical extracts and, more specifically, to extracts of passion fruit (Passiflora sp.), including particularly extracts of the skin of passion fruit, and the use of the extracts for food, nutraceutical, and medical applications.
Hypertension, or a blood pressure higher than 140/90 mm Hg, is the most common risk factor for cardiovascular and cerebrovascular morbidity and mortality. In the United States, high blood pressure is responsible for 40,000 deaths annually, while being the most modifiable risk factor for stroke. Hypertension affects about one in four adults, or almost 50 million people in the United States.
A Framingham study showed that as people aged from 30 to 65 years, their blood pressure increased an average 20 mm Hg systolic and 10 mm Hg diastolic pressure, with systolic blood pressure continuing to rise up to age 90.
While higher blood pressure increases the likelihood of a cardiovascular event, hypertension is not often well controlled and too few patients are adequately treated. Epidemiologic studies predict that reduction of the systemic blood pressure by the amount usually achieved in major clinical trials could reduce cerebrovascular events by 42% and cardiac events by 24%
Hypertension is frequently treated non-specifically, resulting in a large number of minor side-effects, and a relatively high rate of non- or inadequate treatment. Thus, the search for new treatments for hypertension remains ongoing.
Therapies derived from natural products are welt-known. It has been established that certain flavonoids have a beneficial effect on hypertension. For example, a bark extract from the French maritime pine (Pinus pinaster), which contains a mixture of flavonoids, decreases systolic blood pressure when taken orally by mildly hypertensive patients.
Nitric oxide is an important molecular regulator of blood pressure. Nitric oxide is a potent vasodilator. It inhibits platelet activation, limits leukocyte adhesion to the endothelium, and regulates myocardiocontractility. Synthesis of nitric oxide catalyzed by nitric oxide synthase (NOS) occurs in the vascular endothelium while the production of nitric oxide involving inducible nitric oxide synthase (iNOS) is associated with immune function. However, small amounts of nitric oxide produced by another NOS, epithelial nitric oxide synthase (eNOS), have a cytoprotective effect and vasodilation action on the cardiovascular system.
Peroxynitrite is a potentially damaging oxidant, formed from nitric oxide (NO+O2 ONOO−). Peroxynitrite can give rise to lipid peroxidation, protein nitration, DNA single-strand breakage, and guanidine nitration.
It has been shown that the flavonoids quercetin and kaempferol inhibit NOLA-dependent spontaneous aortic ring contraction in spontaneously hypertensive rat (SHR) cells in vitro. NOLA is a nitric oxide synthase inhibitor. Large dose acetylcholine-induced vascular contraction can also be inhibited by antioxidative flavonoids such as quercetin, kaempferol, rutin, and esculetin. Inhibition of vascular smooth muscle contraction should lead to lower blood pressure.
In addition, the effects of flavonoids on immune function are controversial. Catechin enhances proliferation of lymphocytes and antibody production, while it exerts an inhibitory effect at high concentration. Some studies show that flavonoids enhance NK cell activity, while other studies show that flavonoids have no effect. Quercetin seems to inhibit non-specific immunological responses and exerts an anti-inflammatory action.
Passion fruit (Passiflora edulis) is a subtropical or tropical plant with a vigorous climbing character, growing to 20 ft. The purple passion fruit is native from southern Brazil through Paraguay to northern Argentina. Its fruit is nearly round or ovoid, 1.5 to 3 inches wide, with a tough, smooth and waxy rind.
In a search for bioactive constituents of passion fruit, it has now surprisingly been found that a passion fruit extract lowers systolic blood pressure in spontaneously hypertensive rats (SHR), and decreases nitric oxide production from iNOS, thus improving endothelial dysfunction in SHR. It is therefore also envisaged that the passion fruit extract will exhibit antioxidant properties.
It is therefore an object of the invention to provide an extract of passion fruit which exhibits therapeutic effects against hypertension, and diseases associated with hypertension, and which is hepatoprotective, or at least to provide a useful choice.

Extracts of passion fruit and uses thereof


A cutoff device with a liquid bag includes a framed housing that supports a cover having a cutoff wall. The cutoff wall is opened at a lower end thereof with a liquid bag attached along the opened lower end of the cutoff wall. The housing includes telescopic columns, upper support frames coupled to the upper ends of the telescopic columns, and a lower support frame coupled to the lower ends of the telescopic columns. The upper end of the liquid bag may be fastened to the opened lower end of the cutoff wall using a zipper. The liquid bag contains liquid, such as water, therein, with a heavy substance, such as sand, soil and powdered or granulated metal, added to the liquid.

Generally, a fluid cutoff device is configured to prevent water contamination, when sludge is removed from a riverbed using a suction-type dredge. An example of the dredge will be described with reference to FIGS. 1 and 2. As shown in the drawings, the dredge includes a hydraulic pump 2, a vacuum generating unit 3, and a height adjustable ladder 4 that are provided at predetermined positions on a dredger. Further, the dredge includes a suction pipe 5 which is supported by the ladder 4 to vary the depth of the suction pipe 5, and a suction head 6 which is mounted to a lower end of the suction pipe 5. The position and angle of the ladder 4 are adjusted so that the suction head 6 comes into contact with a riverbed 7. A hydraulic hose is coupled to the suction head 6, so that hydraulic pressure is transmitted from the hydraulic pump 2 to the suction head 6. Further, a flow restriction means, namely, a fluid cutoff device is provided at a position around the suction head 6 to vertically move along the suction pipe 5 of the suction-type dredge.
The fluid cutoff device includes a cover 10, a skirt 11, a heavy substance 12, and a rope guide means 20. The cover 10 covers a portion around the suction head 6, and has at a center thereof a pipe guide hole 16 to receive and guide the suction pipe 5. The skirt 11 is mounted to a lower end of the cover 10 and is made of a flexible material. The heavy substance 12 is provided on a lower end of the skirt 11. The rope guide means 20 is integrally provided on an upper surface of the cover 10 to move the cover 10 up and down.
The rope guide means 20 is constructed to guide a rope 21 using a rope drawing motor 22 which is installed at a predetermined position on the dredger, thus winding or unwinding the rope 21.
As shown in FIG. 2, it is preferable that reinforcing ribs 13 be radially provided on the cover 10 at regular intervals, thus increasing the durability of the cover 10. Further, holes 14 are formed on the cover 10 to decrease pressure which is generated during the vertical movement of the cover 10. The cover 10 also includes a ring-shaped support frame 15 to form the pipe guide hole 16.
The conventional cutoff device performs a function of decreasing pressure during the initial downward movement of the cover in dredging work. However, the cutoff device has a problem in that contaminants generated during the dredging work leak out, thus causing environmental contamination.


A light source and a substrate are placed above and below a mask having a mask pattern thereon, respectively. Relative to the mask, the light source is moved in a first direction at a first speed, and the substrate is moved in a second direction at a second speed. The light of the light source transfers the mask pattern to a photoresist layer on the substrate, and forms a photoresist pattern thereof.

1. Field of Invention
The present invention relates to a manufacturing apparatus and method for a semiconductor. More particularly, the present invention relates to a scanning exposure method and an apparatus thereof.
2. Description of Related Art
Liquid crystal display (LCD) has many advantages over other conventional types of displays including high display quality, small volume, light weight, low driving voltage and low power consumption. Large size, high resolution, wide view and rapid response time are the main demands on the LCDs. From the LCDs used in desktop computers to the popular liquid crystal televisions, and further the ultra large LCDs, the size of the LCDs is increasingly great.
Generally, the exposure manufacturing process of the large-size LCD is carried out by a scanning exposure method. FIG. 1A illustrates a schematic view of a conventional scanning exposure apparatus. As illustrated in FIG. 1A, the conventional scanning exposure apparatus fixes the positions of a mask 104 and a substrate 106, and moves a light source 102 from one side of the mask 104 to the other side thereof for scanning the whole mask 104. The light of the light source 102 therefore completely transfers a mask pattern of the mask 104 to a photoresist layer of the substrate 106.
FIG. 1B illustrates a schematic view of another conventional scanning exposure apparatus. In contrast to the apparatus in FIG. 1A, the scanning exposure apparatus in FIG. 1B fixes the position of the light source 102, and moves the mask 104 and the substrate 106 synchronously. The same result as that of FIG. 1A is thus attained.
In these conventional scanning exposure apparatuses, with their single-scan exposure procedure, the size of the mask 104 is limited to the size of the substrate 106. The sizes of the modern LCDs are greater, and if the conventional scanning exposure apparatus is used to manufacture the large-size LCDs, the size of the mask thereof has to be greater or, alternatively, a multiple scan exposure procedure has to be used. However, when the size of the mask is greater, the manufacturing cost thereof is very expensive and the yield thereof is also suboptimal. Moreover, the increase of the size of the mask has ultimate limitation. Hence, considering the quality and cost, one conventional method uses a seamless procedure to combine small-size liquid crystal panels and obtain a large-size LCD. But the seamless procedure sometimes joins poorly, thus generating many problems.

Scanning exposure method and an apparatus thereof


The invention relates to a non-cleavable, plastidial targeting polypeptide derived from a protein from the inner membrane of plant chloroplasts. Said peptide is particularly suitable for importing proteins of interest in plants.

Plasts are intracellular organelle of chlorophyll-containing plants (algae, mosses, and higher plants). Several main types of plasts can be distinguished according to their pigment content and the nature thereof: amyloplasts, which are rich in starch, chloroplasts in which the main pigments are chlorophylls, and chromoplasts for which the main pigments are keratonoids. These three categories of plasts which derive from common precursors, proplasts, have a common basic structure consisting of a double membrane enclosing the plastid stroma. In chloroplasts, there is a third membrane system forming, within the stroma, saccules called thylakoids.
Besides their essential role in photosynthesis, chloroplasts are also involved in redox reactions, for example the reduction of nitrates to ammonium. Plasts also play an essential role in the biosynthesis and/or the storage of many molecules, among which mention will be made of starch, lipids, carotenoids, most amino acids, plant hormones (abscissic acid, precursors of gibberellins, jasmonate, etc.).
Although plasts have their own genome encoding some of their proteins, a large number of the enzymes involved in the various plastid functions are encoded by the nuclear genome and imported into the plasts.
This importation is carried out via a specific mechanism, which has more particularly been studied in the case of chloroplasts (for review cf. CHEN and SCHNELL, Trends Cell Biol. 9, 222-227, 1999; KEEGSTRA and CLINE, The Plant Cell 11, 557-570, 1999; SCHLEIFF and SOLL, Planta 211, 449-456, 2000; JACKSON-CONSTAN and KEEGSTRA, Plant Physiol. 125, 1567-1676, 2001). This mechanism involves an import system in each of the two plastid membranes: in the outer membrane, the Toc (translocon at outer membrane of chloroplast) complex which comprises at least three proteins: Toc 86, 75 and 34 (KESSLER et al., Science 266, 1035-1039, 1994; PERRY and KEEGSTRA, Plant Cell 6, 93-105, 1994); in the inner membrane, the Tic (translocon at inner membrane of chloroplast) complex which comprises at least four proteins: Tic 110, 55, 22 and 20 (KESSLER and BLOBEL, Proc. Natl. Acad. Sci. 93, 7684-7689, 1996; LÜBECK et al., EMBO J. 15, 4230-4238, 1996; CALIEBE et al., EMBO J. 16, 7342-7350, 1997; KOURANOV et al., J. Cell Biol., 143, 991-1002, 1998), and also a chaperone protein in the stroma: ClpC (AKITA et al., J. Cell Biol. 136, 983-994, 1997; NIELSEN et al., EMBO J. 16, 935-946, 1997).
A major element of this mechanism is Toc75, which is the most abundant protein in the outer membrane, and forms the central pore of the translocation channel located in this membrane (SCHNELL et al., Science 266, 1007-1012, 1994; TRANEL et al., EMBO J. 14, 2436-2446, 1995). Toc75 interacts specifically with a particular sequence, called "targeting peptide" or "transit peptide", located at the N-terminal end of the proteins imported into the plasts (MA et al., J. Cell Biol. 134, 315-327, 1996).
Many targeting peptides have been identified in the precursors of proteins targeted to the intermembrane space, the inner membrane, the stroma and, in the case of chloroplasts, to the thylakoid membrane.
Among the proteins known to have a cleavable intraplastid-targeting peptide, mention will in particular be made of proteins targeted to the intermembrane space (Tic22: KOURANOV et al., 1998, mentioned above; KOURANOV et al., J. Biol. Chem. 274, 25181-25194, 1999), proteins targeted to the inner membrane (TPT(Triose-Pi/Pi translocator): BRINK et al., J. Biol. Chem. 270, 20808-20815, 1995), proteins targeted to the stroma (ribulose-1,5-bisphosphate carboxylase (Rubisco) small subunit): DE CASTRO SILVA FILHO et al., Plant Mol. Biol. 30, 769-780, 1996; carbonic anhydrase), proteins targeted to the thylakoid membrane (LHCP (light harvesting complex): LAMPPA et al., J. Biol. Chem. 263, 14996-14999, 1988; Cfo-II: ATPase subunit) and to the thylakoid lumen (OEE1 (Oxygen Evolving Element 1): KO and CASHMORE, EMBO J. 8, 3187-3194, 1989).
These targeting peptides generally comprise between 40 and 100 amino acids, and most of them have common characteristics: they are virtually devoid of negatively charged amino acids, such as aspartic acid, glutamic acid, asparagine or glutamine; their N-terminal region is devoid of charged amino acids, and of amino acids such as glycine or proline; their central region contains a very high proportion of basic or hydroxylated amino acids, such as serine or threonine; their C-terminal region is rich in arginine and has the ability to form an amphipathic, beta-sheet secondary structure.
In the case of proteins targeted to the thylakoid lumen, the targeting peptide is bipartite and comprises additional information for crossing the thylakoid membrane (DE BOER and WEISBEEK, Biochim. Biophys. Acta. 1071, 221-253, 1991). In certain cases, this bipartite targeting peptide can also be found in proteins targeted to the thylakoid membrane (KARNAUCHOV et al., J. Biol. Chem. 269, 32871-32878, 1994).
In all cases, the targeting peptide is cleaved after importation. This cleavage is carried out by specific proteases; a protease located in the stroma (VANDERVERE et al., Proc. Natl. Acad. Sci. 92, 7177-7181, 1995), and a protease located in the lumen of the thylakoid (CHAAL et al., J. Biol. Chem. 273, 689-692, 1998) have been described.
Proteins targeted to the outer membrane do not generally comprise a cleavable signal peptide; the targeting information is contained in the mature protein (CLINE and HENRY, Annu. Rev. Cell Dev. Biol., 12, 1-26, 1996); after they have been synthesized in the cytosol, these proteins are directly incorporated into the membrane (VAN'T HOF et al, FEBS lett. 291, 350-354, 1991 and J. Biol. Chem. 268, 4037-4042, 1993; PINADUWAGE and BRUCE, J. Biol. Chem. 271, 32907-32915, 1996) by means of interactions, the nature of which remains poorly understood, with the lipid bilayer. The only known exception to date concerns the Toc75 protein or (OEP75), the targeting of which to the outer membrane requires the presence of a cleavable, bipartite N-terminal targeting peptide (TRANEL et al., 1995, mentioned above; TRANEL and KEEGSTRA, Plant Cell 8, 2093-2104, 1996).
It is known that the use of plast-targeting peptides is necessary for introducing into these plasts proteins of interest for acting on various plastid functions, in particular with the aim of improving the characteristics of plants of agronomic interest, for example the biosynthesis of lipids, of starch, of vitamins, of hormones or of proteins by said plants, or their resistance to diseases, to insects or to herbicides. For example, application EP 189707 proposes the use of cleavable targeting peptides derived from chloroplast protein precursors, and in particular of the ribulose-1, 5-bisphosphate carboxylase small subunit targeting peptide, for importing a protein of interest into chloroplasts; PCT application WO 00/12732 proposes the use of targeting peptides from various plastid proteins, for importing proteins of interest into plasts.
The plastid functions can be modified in this way, and the characteristics conferred by these modifications are very diverse.
For the purposes of nonlimiting illustration, mention may be made of:                an increase in herbicide resistance, by expression of the precursor of acetolactate synthetase (ALS), (LEE et al. EMBO J., 7, 1241-1248, 1988), of mutated acetolactate synthetase (PRESTON and POWLES, Heredity 88, 8-13, 2002); CHONG and CHOI, Biochem. Biophys. Res. Commun. 279, 462-467, 2000), or of 3-enolpyruvylshikimate-5-phosphate synthetase (EPSP synthetase) (KLEE et al., Mol. Gen. Genet., 210, 437-442, 1987);        an increase in resistance to various stresses, by expression of zeaxanthin epoxidase, (SEO et al., Trends Plant Sci., 7, 41-48, 2002), of choline monooxygenase (SHEN et al., Sheng Wu Gong Cheng Xue Bao, 17, 1-6, 2001), of the product of the ERD1_ARATH gene (KIYOSUE et al., Biochem. Biophys. Res. Commun., 15, 196, 1214-1220, 1993), of ferrochelatase (CHOW et al., J. Biol. Chem., 31, 272, 27565-27571, 1997), of omega −3 fatty acid desaturase (IBA et al., Tanpakushitsu Kakusan Koso, 39, 2803-2813, 1994; MURAKAMI et al., Science 21, 287(5452), 476-479, 2000), or glutamine synthetase (FUENTES et al., J. Exp. Bot., 52, 1071-1081, 2001);        modification of plast metabolism, so as to increase the capture of light energy (GAUBIER et al., Mol. Gen. Genet., 1, 249, 58-64, 1995), the photosynthetic and growth capacities (MIYAGAWA et al., Nature Biotech., 19, 965-969, 2001), the carotenoid content (HUGUENEY et al., Eur. J. Biochem., 1, 209, 399-407, 1992; MANN et al., Nature Biotech., 18, 888-892, 2000), or the content of various substances of interest, such as starch (PCT application WO 00/11144), essential amino acids (MUEHLBAUER et al., Plant Physiol., 106, 1303-1312, 1994), provitamin A (RÖMER et al., Nature Biotech., 18, 666-669, 2000), hormones (JOYARD et al., Plant Physiol. 118, 715-723, 1998), etc.;        overexpression and chloroplast-targeting of proteins that can be used for the purposes of bioremediation (detoxification or depollution of contaminated soils), such as ferritin, (LOBREAUX et al., Biochem. J., 15, 288(Pt 3), 931-939, 1992), proteins of the phytochelatin family (CAZALE and CLEMENS, FEBS 507, 215-219, 2001 ; TSUJI et al., BBRC 293, 653-659, 2002), etc.
All the intraplastid-targeting peptides known in the prior art make it possible to import a protein into plasts by means of the TOC and TIC membrane import systems, as indicated above. It has been noted that the use of these peptides for targeting proteins of interest into chloroplasts may, in particular when the targeting peptide/protein of interest construct is placed under control of a strong promoter such as the 35S promoter, has the drawback of saturating these import systems, by competing with the proteins naturally targeted to the chloroplast. As a result of this, "leakages" occur, resulting, after a few days, in the presence of the protein of interest in other subcellular compartments such as the cytoplasm.
It would be desirable to have intraplastid-targeting peptides which would not depend on the TOC/TIC import system and would therefore make it possible to avoid the abovementioned drawbacks.
In previous studies aimed at identifying, by means of a proteomic approach, proteins from spinach chloroplast membrane preparations, the inventors identified, inter alia, peptides having considerable sequence similarity with a putative 41 kDa protein from Arabidopsis (TrEMBL accession number Q9SV68) (SEIGNEURIN-BERNY et al., Plant. J. 19, 217-228, 1999; FERRO et al., Electrophoresis 21, 3517-3526, 2000).


A filler neck for a fuel tank of a motor vehicle is provided. The filler neck comprises a filler pipe with a longitudinal axis and a circular cross section with an inner diameter. The filler neck further comprises a blocking element that is arranged inside the filler pipe and extends only inside a circle sector of a circle concentric to the circular cross section. The circle has a circle diameter that is smaller than the inner diameter. The circle sector has an angle at the center of less than 180°.

1. Field of the Invention
The present invention relates to a filler neck for a fuel tank, in particular filler necks for a fuel tank of a motor vehicle, which prevent incorrect fueling with an incorrect fuel type.
2. Description of the Background Art
Motor vehicles, for example, automobiles or transport vehicles, can be operated with gasoline or diesel depending on a type of installed internal combustion engine. In the event of incorrect fueling, for example, when a diesel vehicle is fueled with gasoline, considerable damage can be caused to the vehicle during the operation of the vehicle. Furthermore, substantial costs can be incurred by emptying the fuel system after an incorrect fueling.
Diesel tank filler necks of today's automobiles usually have an opening for the hose nozzle of more than 23 mm. A spout of a diesel hose nozzle has an outer diameter of approx. 23 mm. A spout of a gasoline hose nozzle has a smaller outer diameter than the diesel hose nozzle. In the case of gas tank filler necks, the opening diameter is only a few millimeters larger than the outer diameter of the gasoline hose nozzle. The opening of the gasoline tank filler neck is 20 mm, for example. Thus only a gasoline hose nozzle fits into the opening of the gasoline tank filler neck, whereby an incorrect fueling of the gasoline vehicle can be prevented. On the other hand, diesel hose nozzles as well as gasoline hose nozzles fit into the opening of the diesel tank filler neck.
In the prior art, therefore a plurality of methods and devices are known which are designed to prevent an incorrect fueling of a diesel vehicle with gasoline.
DE 10 2005 010 530 A1, for example, relates to a warning device for fueling vehicles with the correct fuel. The device comprises a transmitter, for example, an RFID chip, and a reader device. The transmitter is attached to the vehicle and the receiver is attached to a fueling device. When the fueling device approaches the vehicle, the fuel type stored in the transmitter is compared to the fuel of the fuel type that is stored in the reader device. If the fuel is identical, a green light-emitting diode is illuminated. If the fuel is not identical, a red light-emitting diode is illuminated. If the fueling represents a hazard, e.g., gasoline and diesel have been interchanged, an acoustic alarm and a vibration alarm in the reader device are triggered.
DE 10 2009 009 998 A1, which corresponds to US 20110315682, relates to a safety element for a diesel fuel tank to prevent adding the wrong fuel. An insert element for a diesel fuel tank can be installed in the filling opening of the tank for the purpose of a hose nozzle fueling with diesel fuel at the gas station side. The insert element has an elongated tubular securing element which can be fitted into the container opening with an inlet side and an outlet side, in which a molded part, which is elongated parallel to the securing element, is secured, the free end side of which projecting towards the inlet side in the outer diameter on the one hand is smaller than the inner diameter of the spout of a diesel hose nozzle, but on the other hand is larger than the inner diameter of a gas pump nozzle spout. Furthermore, an actuation element which can be displaced coaxially to the filling opening on the inner wall of the securing element is provided, which actuation element is arranged set back behind the end side of the molded part in the direction of the interior of the tank and is capable, when displaced in the direction of the interior of the tank, of actuating a closure flap which is arranged on the outlet side of the securing element.
DE 10 2008 039 150 A1 relates to a safety element for a diesel fuel tank for preventing incorrect fueling. A tubular molded part is provided, the outer diameter of which on the one hand is smaller than the inner diameter of a spout of a diesel pump nozzle, but on the other hand is larger than the inner diameter of a gas pump nozzle spout.
DE 10 2009 049 482 A1 relates to a diesel tank adapter. The diesel tank adapter functions such that the hose nozzle is pushed over a tank neck. The tank neck is thus inserted into the hose nozzle. The diesel tank adapter prevents an incorrect fueling with gasoline by utilizing the different diameters of the two types of hose nozzle.
DE 10 2009 056 512 A1 relates to a filling system for a fuel tank. The filling system has a filling opening and a blocking device for filler pipes provided for the filling opening, which blocking device in its design differs from that of a target filler pipe for a specific fluid. The blocking device has a blocking insert, which comprises a plug-on mandrel matching the target filler pipe and movable in a path-limited manner to the filling opening for the target filler pipe.
DE 10 2008 027 462 A1 relates to an insert element for a fuel tank, which is designed for filling with diesel fuels. The accidental filling of gasoline into the fuel tank can be prevented by means of the insert. The device has an inner flank, the one end of which is wider than the standardized inner diameter of a spout provided for gasoline pump nozzles, but smaller than the standardized inner diameter of a spout provided for diesel fuel pump nozzles.
With the protection against incorrect fueling known from the conventional art with the detection of the inner diameter of the spout of the hose nozzle, such as is known, for example, from DE 10 2009 009 998 A1 or DE 10 2008 027 462 A1, with shut-off mechanisms of the hose nozzle located in the spout, collisions can occur between the shut-off mechanism and the blocking element of the protection against incorrect fueling.
FIG. 1 shows diagrammatically a conventional filler neck 1 with a filler pipe 2 and a blade-like blocking element 3 arranged therein. Furthermore, FIG. 1 shows a cross-sectional view of a spout 4 of a hose nozzle with a shut-off mechanism 5 located in the spout 4. Depending on the position of the shut-off mechanism 5 on the inside of the spout 4 and depending on the insert angle of the spout 4 into the filler pipe 2, collisions can occur between the shut-off mechanism 5 and the blocking element 3. FIG. 2 shows a lateral cross-sectional view of the filler neck 1 and the spout 4 with the shut-off mechanism 5 arranged therein. FIGS. 3 and 4 show the collision situation, in which the shut-off mechanism 5 knocks against the blocking element 3, whereby an insertion of the spout 4 into the filler pipe 2 is prevented. FIG. 3 shows a cross-sectional view of the filler neck 1 and of the spout 4 and FIG. 4 shows a lateral cross-sectional view of the filler neck 1 and of the spout 4.
Although the position of the shut-off mechanism 5 inside the spout 4 is fixed, depending on a rotation angle with which a user tries to insert the spout 4 of the pump nozzle into the tank filler neck 1, the shut-off mechanism 5 can be located at any desired position based on the blocking element 3. A twisting of the spout 4 can occur in particular when the vehicle is not oriented optimally to the gas pump and the hose is guided over the vehicle or around the vehicle, for example, between the gas pump and the pump nozzle, whereby the pump nozzle is used in a correspondingly twisted manner.


A method for processing a substrate article is provided. The method includes masking a first portion of the substrate article with a maskant that includes a formed graphite piece that overlays and contacts the first portion of the substrate such that a second portion of the substrate is not overlaid nor contacted by the maskant; and processing the substrate article such that a coating of material is deposited on the second portion of the substrate, and wherein the maskant facilitates preventing the coating from being deposited on the first portion of the substrate article.

The invention relates generally to components of the hot section of gas turbine engines, and more particularly, to a process for depositing a coating onto a selective area of a turbine component.
In gas turbine engines, for example, aircraft engines, air is drawn into the front of the engine, compressed by a shaft-mounted rotary compressor, and mixed with fuel. The mixture is burned, and the hot exhaust gases are passed through a turbine coupled to a shaft. The flow of gas turns the turbine, which drives the compressor. The hot exhaust gases flow from the back of the engine, providing thrust that propels the aircraft forward.
During operation of gas turbine engines, at least some components within the engine, maybe in contact with high temperature gases. Such components may include, for example, blades, vanes, and nozzles used to direct the flow of the hot gases.
To facilitate shielding the metallic parts from the combustion gases, environmental coatings may be applied to the components. Such environmental coatings may be produced by holding the part to be coated at a temperature in an atmosphere that is rich in a certain element or elements, often aluminum. The elements diffuse onto the surface of the part and form a diffusion coating in a process known as diffusion aluminide. In one form, the environmental coating is fabricated from a diffusion cobalt aluminide, nickel aluminide or platinum aluminide. The diffusion aluminide coating surface forms an aluminum oxide scale when exposed to oxygen-containing atmospheres at elevated temperatures, thus facilitating increased resistance to additional high temperature oxidation.
At least some other known component coating processes demand labor-intensive processes. For example, when the component is a low pressure turbine (LPT) nozzle, known coating processes require a labor intensive masking process wherein a commercially available aluminum gettering masking tape is applied to the desired area of the turbine component. More specifically, the tape is affixed in place using a sheet metal strip. However, continued exposure to the high temperatures utilized by the coating process, may cause the sheet metal strip to warp, such that the strip fails to provide adequate support for the masking tape. As a result the masking tape may undesirably dislodge from the component during the aluminide coating process, and an undesired area of the turbine nozzle may be aluminided.

Methods and apparatus for turbine engine component coating


A battery package (100) includes a latch (106) for easy attachment to a radio (402). Engagement of the battery package (100) to the radio is accomplished via matching a plurality of retaining rails (110) via notches (112) with a plurality of opposing and complementary retaining rails on the radio (402). A simple sliding motion locks the latch (106) to the radio (402). Disengagement requires little force as the latch (106) is depressed in the same direction as the battery package (100) is slid down. The battery comes to a stop when an alignment of the notches (112) with the radio retaining rails has taken place. An effortless lift separates the battery package (100) from the radio (402).

The design of battery latches particularly ones on a portable electronic device is known in the art. However, present battery latches are plagued with mechanical reliability issues due to an inability to survive abuse over the life of the battery. These battery latches have finger grips which require a significant amount of force, in a number of directions, in order to engage and disengage the battery. As a result of the direction changes, the design of the battery latches is not ergonomically efficient. Moreover, these battery latches break when in use or when the electronic device is being transported. A need exists for an ergonomically designed battery latch which has ease of access, protective features, and a nominal force to actuate the battery latch in the direction of battery engagement and disengagement.

Battery latch for a communication device


To provide improved security in adjunct program modules such as plug-ins and dynamic link libraries, a requesting module provides an authorization interface to the invoked module such that the invoked module can require a certificate of the requesting module and can also challenge the authority of the requesting module. The certificate can include one or more permissions which are prerequisites for processing by the invoked module.

Computer programs are currently made extensible and efficient by the use of adjunct program modules such as plug-ins and dynamic link libraries. Plug-ins are computer program modules which can alter the behavior of a computer program without changing the computer program itself. A common example of plug-ins are those associated with currently ubiquitous web browsers. Briefly, a web browser is a computer program by which a user retrieves multimedia documents and information through that portion of the Internet known as the World Wide Web. Installation of plug-ins allow modification of the behavior of the web browser without re-installing or otherwise changing the computer instructions of the web browser itself. One example of such extended functionality is the embedded display of images of the Tagged Image File Format (TIFF). Such functionality is not provided by some web browsers currently, but installation of certain plug-ins add that functionality. To use the plug-in, applications such as web browsers are designed to look for installed plug-ins and, if installed, invoke execution of those plug-ins upon activation of a particular function or activity.
Plug-ins can sometimes be implemented as dynamic link libraries. Dynamic link libraries can be used for other purposes as well. A dynamic link library is a collection of program modules which are generally not loaded until invoked by another program. The following example will illustrate. Consider a web browser which provides a spell-checking capability for forms data entry. A web browser is typically a resource-intensive program such that a considerable amount of memory is used when the web browser is executing. A spell-checker can also be resource-intensive. By implementing the spell-checker as part of a dynamic link library, execution of the web browser does not immediately load the spell-checker into memory. Accordingly, the resources required for the spell-checker are not immediately consumed. Instead, the spell-checker is loaded for execution only when a user requests a spell checking function of the web browser. Such allows the web browser to execute more efficiently when the spell-check function is not invoked.
For reasons pertaining both to extensibility and efficiency, adjunct program modules such as plug-ins and modules of dynamic link libraries are quite popular. An additional factor in the popularity of such adjunct program modules is the simplicity with which they are implemented. To facilitate the use of adjunct processing modules, such modules are designed to be very easily identified and invoked. Virtually no safeguards are used to ensure only a specifically authorized computer program invokes execution of a particular adjunct program module.
The lack of security in adjunct program modules is a significant problem. The following example is illustrative. Consider that a computer user has collected a number of musical songs in the ubiquitous and renowned MP3 digital format and plays the songs on a computer using an MP3 player program. Consider further that the user has purchased and downloaded a number of songs in a secure, copy-protected format but wishes to play those songs along with the other songs in the MP3 format. The MP3 player program can be augmented with a plug-in adjunct program module to decode and play the secure, copy-protected format. Such an adjunct program module, when requested, can decode the secure, copy-protected music and produce un-secured, un-protected music for reproduction through the computer's sound logic and loudspeakers.
However, due to the accessibility of conventional adjunct program modules, any program could request decoding of the secure, copy-protected music data by the decoding adjunct program module. Accordingly, a cracker could write a simple program to request decoding from the adjunct program module and to re-write the decoded music in the MP3 format. The resulting MP3 music data file could have identical sound quality and could be distributed worldwide through the Internet without any encryption security or copy-protection. Such would represent a catastrophic failure of the secure, copy-protected format decoded by the adjunct program module.
What is therefore needed is a security mechanism by which adjunct program modules can limit service to authorized program modules. Such would enable security-reliant computer processes to avail themselves of the benefits and advantages of adjunct program modules.

Security mechanism for computer processing modules

Abstract: The invoked module can challenge the authority of the requesting module by sending random test data to the requesting module and receiving in response a cryptographic signature of the test data. By verifying the signature of the requesting module using the received certificate, the invoked module confirms that the requesting module is, in fact, the owner of the receive certificate.


A temperature correction device may allow ready calibration. In certain implementations, a temperature correction device may include a torsion transmission element and a temperature responsive element. The temperature responsive element may be coupled to the torsion transmission element and adapted to rotate the torsion transmission element in response to sensed temperature changes. The temperature correction device may also include a first body coupled to the torsion transmission element, a second body coupled to the temperature responsive element, and a third body rotatably coupled to the second body. The first body may include a temperature correction component driven by the torsion transmission element, and the second body and the third body may be adapted to allow the torsion transmission element to rotate relatively freely with respect to the second body and the third body. Rotation of the second body relative to the third body may adjust the temperature correction component.

Temperature correction devices and techniques are used in a wide variety of environments for commercial and industrial applications. For example, temperature correction devices and techniques may be used for correcting for the temperature of fluids (gas and/or liquid) in pipelines or storage facilities. Many volumetric gas flow meters, for instance, require temperature correction to properly register the amount of gas passing therethrough. Such devices may use mechanical or electrical techniques to perform the temperature correction.
Common temperature correction devices and techniques use resistive thermocouples, resistive temperature devices, gas-filled Bourdon tubes, or bimetal coils to sense temperature. Bimetal coils have found favor because they may be readily manufactured at low cost, have good accuracy, and have long-term stability.
Bimetal coil temperature measurement devices include a bimetal coil that torsionally responds to temperature changes. A shaft is commonly disposed through the center of the coil and coupled to the coil at one end. The shaft is also commonly coupled to an indicator assembly. In operation, when the coil responds to a temperature change, the torsion is relayed to the shaft, causing it to rotate. The rotation of the shaft is then relayed to the indicator assembly, which produces an indication of the temperature sensed by the coil. Thus, a technician may read the temperature at the device.
When calibrating a temperature measurement device that uses a bimetal coil for measurement of natural gas, the device is commonly inserted into a bath at 60° F., which is the standard base temperature for natural gas. If the device does not indicate 60° F., the device is extracted from the bath and either portions of the coil are welded together or portions of the coil are welded to other components of the device. The device is then inserted into the bath again and checked for proper indication. This process of checking for proper indication and welding together of components to compensate for inaccuracy may be continued over several cycles.

Adjustable temperature correction device


A bicycle frame comprising a first tubular member having a first interface portion, and a second tubular member having a second interface portion engaged with the first interface portion to create a joint. The joint includes a peripheral channel having a depth that is greater than a wall thickness of the first tubular member, and a weld is positioned in the peripheral channel. To enhance the transition from the first main portion to the second main portion, the second tubular member can include a fillet surface between the second main portion and the second interface portion. The fillet surface is contoured to provide a smooth transition between the top tube and the head tube. An outer surface of the first interface portion can be offset from an outer surface of the first main portion to thereby create a shoulder.

The present invention relates to bicycle frames, and particularly to weld joints of tubular bicycle frames.
Bicycle frames are commonly manufactured from tubes that are coupled together into a desired configuration. When the tubes are metal (e.g., steel, aluminum, titanium, etc.), they can be welded together to form the bicycle frame. When manufacturing a welded bicycle frame, the ends of the tubes are pre-cut so that the tubes fit together to form pre-weld joints between the tubes. For example, one tube can be mitered so that it wraps snugly around the tube to which it will be welded. When tubes of similar size are coupled using a mitered joint, the geometry of the joint varies dramatically around the tube interface, from essentially a T-joint at the top and bottom to essentially a tangent joint on the sides, with the mitered tube having a razor thin wall thickness at the tangent joint.
When welding tubes having mitered joints, a weld fillet is formed around the joint. Due to the varying joint geometry of the above-described mitered joint, creating a good, consistent weld is very difficult. At the location where the tubes are tangent, the weld bead commonly protrudes substantially above the surfaces of the tubes being welded. If a smooth joint is desired, one would need to grind or sand the weld bead.


A wireless power transmitter which wirelessly transmits a power to a wireless power receiver. The wireless power transmitter includes a transmission resonance coil configured to wirelessly transmit a power; a power source configured to supply the power to the transmission resonance coil; and a detector configured to detect an existence state of the wireless power receiver. Further, the power source supplies the power with a transmission pattern which is discrete at a predetermined time interval for a specific time to detect the existence state of the wireless power receiver and minimize a loss of the power, and the power source continuously supplies the power if the wireless power receiver exists.

1. Field of the Invention
The disclosure relates to a wireless power transmitter and a wireless power transmission method thereof. In more particular, the disclosure relates to a wireless power transmitter capable of effectively transmitting power by actively controlling the power according to the recognition of a wireless power receiver, and a wireless power transmission method thereof.
2. Discussion of the Related Art
A wireless power transmission or a wireless energy transfer refers to a technology of wirelessly transferring electric energy to desired devices. In the 1800's, an electric motor or a transformer employing the principle of electromagnetic induction has been extensively used and then a method for transmitting electrical energy by irradiating electromagnetic waves, such as radio waves or lasers, has been suggested. Actually, electrical toothbrushes or electrical razors, which are frequently used in daily life, are charged based on the principle of electromagnetic induction. Until now, the long-distance transmission using the magnetic induction, the resonance and the short-wavelength radio frequency has been used as the wireless energy transfer scheme.
The wireless power transmission system includes a transmitter and a receiver. The transmitter wirelessly transmits power to the receiver, and the receiver receives the power from the transmitter and performs the operation according to the reception of the power.
In this case, since the transmitter cannot recognize the operating state of the receiver, the transmitter continuously transmits power to the receiver so that the receiver can normally operate always.
However, the transmitter always transmits the power to the receiver regardless of the operating state of the receiver as described above, so that high voltage is applied to the coil of the transmitter. Accordingly, when power is transmitted to the receiver thereafter, the erroneous operation or the breakage of the transmitter may occur. In addition, since the transmitter transmits the predetermined quantity of power to the receiver regardless of the quantity of power required by the load of the receiver, remaining power except for the power used in the load of the receiver may be wasted.

Wireless power transmitter and wireless power transmission method