【摘要】 讨论了甲苯和均三甲苯烷基转移与歧化反应制备二甲苯过程中Hβ负载磷钨酸系列催化剂的催化性能。结果表明:反应主要为甲苯烷基转移和均三甲苯歧化反应;随着催化剂中Hβ上磷钨酸负载量的增加,均三甲苯转化率、二甲苯选择性和收率均先增加后减少,当磷钨酸质量分数为10%时,总酸量达到最大,总转化率、二甲苯收率及二甲苯选择性也分别达到最大值,即77.0%、38.5%和51.1%。催化剂XRD图谱显示负载的磷钨酸高度分散于Hβ分子筛表面,对载体晶体结构无影响。更多还原

【Abstract】 The effect of phosphotungstic acid(PW) supported by Hβ on the transalkylation and disproportionation of methylbenzene and 1,3,5-trimethylbenzene to produce dimethylbenzene was studied.The results indicate that the transalkylation of methylbenzene and the disproportionation of 1,3,5-trimethylbenzene are the main reactions.With increasing the PW content loaded on the Hβ catalyst,the conversion of 1,3,5-trimethylbenzene,the selectivity and yield of dimethylbenzene increase at first and then decrease.When the mass fraction of Hβ-supported PW is 10%,the total activity reaches maximum,and the overall feed conversion,the yield and the selectivity of dimethylbenzene are 77.0%,38.5% and 51.1%,respectively.XRD patterns of the catalysts indicate that the PWs are highly dispersed on the surface of Hβ-support and have no effect on the crystal structure of support.更多还原