How are the unreacted gases separated out in ‘Bosch process’ in the manufacture of hydrogen.
Separation of CO2: The above mixture passed through KOH sol. under pressure CO2 dissolves leaving behind hydrogen.
2KOH + CO → K2CO3 + H2O
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
Thus hydrogen gas is left over.