Application of catalysts to coal gasification with carbon dioxide

Abstract

The effects of the additives of iron, nickel, zinc, and their oxides on the process of coal gasification with carbon dioxide at temperatures of 550–800°C was studied. It was found that the additives used did not exhibit noticeable activity upon mixing with coal. Impregnation with nickel was found most efficient; it caused a notable increase in the rate of the process and a higher degree of CO 2 conversion, as compared with the thermodynamically equilibrium conversion for a given temperature. Thus, impregnation with 5% nickel made it possible to decrease the reaction temperature by 80°C with the retention of the yield of CO at about 100%. Kinetic models for describing noncatalytic and catalytic gasification reactions were considered and a mechanism of the process in the presence of nickel was proposed.