The catalyst used in Bosch process of manufacture of H2 is:
(a) finely divided Ni
(d) Fe2O3 + Cr2O3
In this process water gas (CO + H2, prepared from coal and water at 1270 K) is mixed with two times its volume of steam passed over catalyst Fe2O3, in the presence of promoter Cr2O3 or ThO2 at 773 K giving products CO2 and H2.
CO2 is dissolved in water under pressure (20 to 25 atm) and is removed leaving behind un dissolved H2.