Question

Describe briefly, with equations, the Bosch Process for the large scale production of hydrogen.

Answer 1

Bosch process for large production of H₂ :

(i) Steam is passed over coke at 1000°C to convert it into water gas

\[\ce{C +\underset{\text{Steam}}{H2O} ->[1000°C]\underset{\text{water gas}}{[Co + H2]} -\triangle}\]

(ii) Water gas is mixed with excess of steam and passed over heated Fe₂O₃ at 450°C in presence of Cr₂O₃ as promotor

\[\ce{\underset{\text{water gas}}{[CO + H2]} + H2O ->[catalyst(Fe2O3)450°C][Cr2O3] CO2 + 2H2 +\triangle}\]

(iii) Separation of CO₂: The above mixture passed through KOH sol. under pressure CO₂ dissolves leaving behind hydrogen.

2KOH + CO₂ → K₂CO₃ + H₂O

(iv) Separation of CO: The gaseous mixture of [CO and H₂] is passed through ammonical cuprous chloride solution in order to dissolve uncombined CO.
CuCl + CO + 2H₂O → CuCl.CO.2H₂O