The Bosch reaction is a catalytic chemical reaction between carbon dioxide (CO2) and hydrogen (H2) that produces elemental carbon (C,graphite), water, and a 10% return of invested heat. CO2 is usually reduced by H2 to carbon in presence of a catalyst (e.g. iron (Fe)) and requires a temperature level of 530–730°C (986–1,346°F).[1][2]
The overall reaction produces 2.3×103joules for every gram of carbon dioxide reacted at 650 °C. Reaction temperatures are in the range of 450 to 600 °C.
The reaction can be accelerated in the presence of an iron, cobalt or nickelcatalyst. Ruthenium also serves to speed up the reaction.
Applications
Together with the Sabatier reaction, the Bosch reaction is studied as a way to remove carbon dioxide and to generate clean water aboard a space station.[3]
The Bosch reaction is being investigated for use in maintaining space station life support. Though the Bosch reaction would present a completely closed hydrogen and oxygen cycle which only produces atomic carbon as waste, difficulties in maintaining its higher required temperature and properly handling carbon deposits mean that significantly more research will be required before a Bosch reactor can become a reality. One problem is that the production of elemental carbon tends to foul the catalyst's surface, which is detrimental to the reaction's efficiency.
Notes
↑ Messerschmid, Ernst and Reinhold Bertrand. Space Stations. Springer. 1999.
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