Chloromethane Conversion to Higher Hydrocarbons over Zeolites and SAPOs

Chloromethane transformations were carried out over zeolites and SAPOs and the conversion and product distribution differed from the porous structure and acidity of the catalysts. Chloromethane was mainly transferred to higher hydrocarbons in gasoline range over most of zeolite catalysts, while SAPOs molecular sieves, SAPO-34 and SAPO-5, showed high selectivity for light olefins production, such as ethylene, propylene and butenes. TG analysis was used to study the coke formation during the transformation and the acid difference of the catalysts was evidenced by Temperature programmed desorption of ammonia. HZSM-5, with high activity and less coke formation, was proved to be a potential catalyst for hydrocarbons production from chloromethane conversion. It is of particular interest that SAPO-34 gave an excellent performance in light olefins production from chloromethane transformation, which may be attributed to the shape selectivity and medium strong acidity of SAPO-34.