Research progress of the influence of alkali metals and alkaline earth metals on coal thermal chemical conversion

In order to comprehensively understand the catalytic gasification process, the influence of AAEMs during coal thermal chemical conversion was compared and explained. The main issues related to the catalytic gasification, such as the transformation of carbon structure, the conversion of alkali metals, and the deactivation of catalysts were discussed. AAEMs can be used as the catalysts for catalytic gasification, the pore making additives for activated carbon preparation, the activating agents in the process of aluminum extraction from coal ash by roasting, but also be regarded as hazard elements for high AAEMs coal utilization. The interaction between AAEMs and carbon can affect the surface structure of carbon to favor the adsorption and reaction of gasification agent on the carbon surface. As the same time, the volatilization and release of AAEMs can not be escaped, but the catalyst recovery can be effectively promoted by coupling the catalytic gasification and the coal ash resource utilization. By understanding the effect of AAEMs on coal thermal chemical conversion, we can propose novel ideas and innovation techniques for coal thermal chemical conversion with AAEMs addition.