reaction has been used in producing graphite flakes, filamentous graphite and lamellar graphite crystallites, as well as producing carbon nanotubes. In graphite production, catalysts used are molybdenum, magnesium, nickel, iron and cobalt, while in carbon nanotube production, molybdenum, nickel, cobalt, iron and Ni-MgO catalysts are used. The Boudouard reaction is an important process inside a blast furnace. The reduction of iron oxides is not achieved by carbon directly, as reactions between solids are typically very slow, but by carbon monoxide. The resulting carbon dioxide undergoes a (reverse) Boudouard reaction upon contact with coke carbon. Undesired occurrence While the Boudouard reaction is used deliberately in some processes, it is undesired in others. In the gas cooled, graphite moderated British nuclear reactors (Magnox and AGR) reaction between the CO2 coolant and the graphite moderator had to be avoided or at least kept to a minimum. As the equilibrium of the reaction shifts in favor of carbon at lower temperatures, this was solved in the Magnox reactor by simply having a lower operating temperature. However, this in turn reduced the achievable thermal efficiency. In the AGR, which was supposed to improve upon the lessons learned from the Magnox, a higher coolant outlet temperature was an explicit design goal (Britain being reliant on coal power at the time, the aim was to achieve the same steam temperature as in coal fired plants) and thus a re-entrant flow of coolant at the lower boiler outlet temperature of is utilized to cool the graphite, ensuring that the graphite core temperatures do not vary too much from those seen in a Magnox reactor. References External links Carbon-heteroatom bond forming reactions Name reactions Gas technologies