甲醇与C4烯烃共裂解效应和催化剂稳定性

摘要

以改性ZSM-5分子筛为催化剂,在固定床反应器上,以甲醇与C<,4>烯烃共裂解制备乙烯和丙烯.结果表明,共裂解有利于促进乙烯和丙烯的生成,对副产物甲烷和碳氧化合物的生成有明显抑制作用,C<,4>烯烃的转化得到促进,C<,5>以上烃类的含量相对增加.同时,甲醇与C<,4>烯烃共裂解时,由于吸热和放热反应能量上的互补以及C<,4>烯烃与甲醇竞争吸附的存在,对延长催化剂的单程操作周期有明显效果.%The modified ZSM-5 zeolites was used as the catalysts for the coupled cracking of methanol and C4 alkenes to ethylene and propylene in a fixed-bed reactor. The results indicated that the co-cracking of two feedstocks was beneficial to the formation of ethylene and propylene, and obviously inhibited the formation of by-products of methane and carbonoxide; C4 olefins conversion was promoted and the contents of C5+ alkanes were enhanced slightly. Moreover, the stability of the catalysts for co-cracking of methanol and C4 alkenes was improved remarkably due to the energy complementation between the exothermic and endothermic reactions and competitive adsorption between methanol and C4 olefins on the catalysts.