Catalytic effect of iron on decomposition of carbon monoxide: I. carbon deposition in H2-CO Mixtures

Research paper by E. T. Turkdogan, J. V. Vinters

Indexed on: 01 Jan '74Published on: 01 Jan '74Published in: Metallurgical and Materials Transactions A


Hematite ore reduced with hydrogen was used as a catalyst in the present investigation of the rate of decomposition of carbon monoxide in H2-CO mixtures. It was found that the amount of carbon deposited from purified carbon monoxide was directly proportional to the amount of porous iron catalyst present in the system. However, this simple relation did not hold for H2-CO mixtures. During carbon deposition the porous iron granules dis-integrated and were dispersed evenly in the carbon deposit. The deposit consisted of graphite, cementite and iron, with cementite/iron ratio increasing as more soot accumulated. When most of the iron was converted to cementite, carbon deposition ceased. A small amount of hydrogen enhanced markedly the rate of decomposition of carbon monoxide. Indications are that hydrogen adsorbed on iron catalyzes the decomposition of carbon monoxide, 2CO → C + CO2, in addition to the occurrence of the second reaction H2 + CO → C + H2O.