Bosch reaction
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).
The overall reaction is as follows:
- CO2(g) + 2 H2(g) → C(s) + 2 H2O(l)
The above reaction is actually the result of two reactions. The first reaction, the reverse water gas shift reaction, is a fast one:
- CO2 + H2 → CO + H2O
The second reaction is the rate determining step:
- CO + H2 → C + H2O
The overall reaction produces 2.3×103 joules 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 nickel catalyst. Ruthenium also serves to speed up the reaction.