苯-乙烯烷基化HZSM-5沸石催化剂积炭失活的研究——Ⅱ.沸石的SiO_2/Al_2O_3比、酸性质与催化剂失活的关系

STUDIES ON COKING AND AGING OF HZSM-5 ZEOLITES FOR ALKYLATION OF BENZENE WITH ETHYLENE Ⅱ. SiO_2/Al_2O_3 RATIOS AND ACIDITY OF ZEOLITES AND DEACTIVATION OF CATALYSIS

通过调变合成母液配比合成出不同SiO_2/Al_2O_3比的ZSM-5沸石系列,对H型催化剂进行苯-乙烯烷基化快速失活反应考察。应用TPD和吡啶吸附红外光谱法研究了沸石的酸性质与积炭失活的关系。结果表明,"特强的"B酸中心是影响活性稳定期的主要因素。

ZSM-5 zeolites with different SiO_2/Al_2O_3 ratios were prepared by altering the composition of the synthesis mixture. Catalyst performance was studied for alkylation of benzene with ethylene over ZSM-5 samples. TPD and IR technique were used to study the relationship between acid sites and coking reaction. The results showed that the"Superstrong" B acid is the main coking deactivation sites.