Coking of Solid Acid Catalysts and Strategies for Enhancing their Activity

摘要

The development of practically viable solid acid catalysts as environmentally safter alternatives to liqueis superacids continues to be a challenge. The major barrier in this regard is the rapid deactivation of the catalsyt due to ffouling by hydrocarbonaceous componds. or coke. This paper revies coke formation pathways on solid acid catalysts for low temperatue (<110degC) processes suc has gasoline alkylate production from isobutane and C_3/C_4 olefins, and skeletal isomerization of n-butane. The formation of coke precursors from feed impurities is also included. The use of near-critical reaction media to effectively balance the coke precursor formation rate with coke precursor removal rate (thereby enhancing catalyst activity) is disucssed. Our results suggest that near-criticl operation in conjunction with rational catalyst design (manipulating parameters such as pore structure and acidity) and proper choice of reactor configuration (stirrd reactor minimizing olefin concentration) have excellent potential for enhancing catalyst activity and product selectivity.