CATALYTIC GASIFICATION OF GAS-COAL CHAR IN CO2

CO2 gasification of a gas-coal char catalysed by Na2CO3 and K2CO3 was studied using a fixed-bed reactor at 790-1020 degrees C and 0.2 MPa. The gasification rate increased with increasing temperature. With increasing addition of Na,CO, in the range 9-25 wt% and K2CO3 in the range 5-20 wt% the rate increased sharply. The catalytic effect of K2CO3 was greater than that of Na2CO3. The effect of catalyst loading on rate showed saturation above 25 wt% for Na2CO3 and 20 wt% for K2CO3. The reaction rate constants and activation energies were measured in the ranges 850-960 degrees C and catalyst loading 1-16 wt%. In this catalytic gasification reaction a compensation effect appeared; the isokinetic temperatures were 1289 degrees C for Na2CO3 and 1466 degrees C for K2CO3.