from foreign producers and obtain about half of its aviation fuel from alternative sources by 2016. Carbon dioxide reuse Carbon dioxide is not a typical feedstock for FT catalysis. Hydrogen and carbon dioxide react over a cobalt-based catalyst, producing methane. With iron-based catalysts unsaturated short-chain hydrocarbons are also produced. Upon introduction to the catalyst's support, ceria functions as a reverse water-gas shift catalyst, further increasing the yield of the reaction. The short-chain hydrocarbons were upgraded to liquid fuels over solid acid catalysts, such as zeolites. Process efficiency Using conventional FT technology the process ranges in carbon efficiency from 25 to 50 percent and a thermal efficiency of about 50% for CTL facilities idealised at 60% with GTL facilities at about 60% efficiency idealised to 80% efficiency. Fischer–Tropsch in nature A Fischer–Tropsch-type process has also been suggested to have produced a few of the building blocks of DNA and RNA within asteroids. Similarly, the hypothetical abiogenic petroleum formation requires some naturally occurring FT-like processes. See also , a generic term for this type of process References Further reading External links Fischer–Tropsch archives Fischer–Tropsch fuels from coal and biomass Abiogenic gas debate (AAPG Explorer Nov. 2002) Gas origin theories to be studied (AAPG Explorer Nov. 2002) Unconventional ideas about unconventional gas (Society of Petroleum Engineers) Process of synthesis of liquid hydrocarbons – Great Britain patent GB309002 – Hermann Plauson Clean diesel from coal by Kevin Bullis Implementing the “Hydrogen Economy” with Synfuels (pdf) Carbon-to-liquids research Effect of alkali metals on cobalt catalysts Biofuels technology Catalysis Coal Organometallic chemistry Petroleum production Synthetic fuel technologies German inventions 1925 in science 1925 in Germany Organic redox reactions Name reactions