金属复合催化剂对煤气化的暂态动力学研究

The step-response transient kinetics techniques have been used for the exploration of the carbon gasification mechanism with the catalysis of metal compounds. According to the experimental results the reaction mechanism of gasification is proposed: firstly, the catalyst releases an oxygen atom from its rich-oxygen site to combine with a carbon atom and create a CO, then the CO molecule desorbs from the catalyst surface; next, the catalyst absorbs a CO2 molecule; and finally on the catalyst surface another CO molecule is created and the original rich-oxygen site gets an oxygen atom. On the basis of gasification process the material balance equations were built, which were solved by using numerrical integral methods and the reaction rate constants for four steps were obtained: they are 0.0703mol·g-1·min-1·kPa-1, 0.0959mol·g-1·min-1·kPa-1, 0.00539 mol·g-1·min-1 and 0.0321 mol·g-1·min-1·kPa-1 respectively. It can be concluded that the absorption of CO2 onto the catalyst is the control step of gasification process.