Experimental study on Hohhot coal hydrogasification catalysed by different metal compounds

The catalysis of K₂CO₃, Na₂CO₃, Ca(OH)₂ and Ni(NO₃)₂ on the hydrogasification of Hohhot coal was studied in a pressurized fixed-bed reactor, in which the effects of temperature were investigated. The experimental results show that different kinds of metal have a significant difference in the catalysis to the hydrogasification reaction, and the order of catalytic activity is as follows: K > Na> Ni > Ca. Compared with the non-catalytic coal hydrogasification, the temperature of hydrogasification catalysed by K₂CO₃ is dropped by more than 150℃ under the same carbon conversion at the same time and reduced about 150℃ by Na₂CO₃ and more than 50℃ by Ni(NO₃)₂. However, the adding of Ca(OH)₂ even decreases the observed carbon conversion due to the sorption of Ca(OH)₂ for CO₂ produced. The SEM and BET results show that coal samples loaded with different metal compounds catalysts have different surface morphologies and pore structures as well.