β沸石催化剂上甲苯歧化及与1,2,4-三甲苯烷基转移反应研究

对在液固相连续反应装置上以β沸石为催化剂进行甲苯歧化及甲苯与1,2,4-三甲苯烷基转移生成二甲苯及苯的反应进行了研究，并对影响反应的因素如温度、压力、氢气用量、反应物空速等进行了探讨。结果表明，该催化剂对上述反应有较好的催化作用。对于甲苯歧化反应，在温度280 ℃，压力3.5 MPa，甲苯重量空速4h^－1，n_氢/n_甲苯＝4∶1时，甲苯转化率为47.26%，苯与二甲苯总选择性为93.50%。对于甲苯与三甲苯的烷基转移反应，当进料比n_甲苯/n_三甲苯=2，温度280 ℃，压力3.5 MPa，总重量空速4 h^－1，n_氢/n_烃=2∶1时，总转化率为47.17%，二甲苯选择性为83.25%，二甲苯收率达39.26%。

Disproportionation of toluene and transalkylation between toluene and 1,2,4-trimethylbenzene over β zeolite catalyst

Disproportionation of toluene and transalkylation between toluene and 1,2,4-trimethylbenzene over β zeolite catalyst were studied in liquid-solid reactor. The appropriate operating conditions were as follows: 280 ℃, 3.5 MPa, toluene WHSV 4 h^－1 and n_H2/n_T=4 for disproportionation of toluene, and 280 ℃, 3.5 MPa, WHSV　4 h^－1，n_H2/(n_T+n_TMB)=2 and n_T/n_TMB=2 for transalkylation. Under the experimental condition, toluene conversion of 47.26% and total selectivity to benzene and xylene of 93.50% were obtained for disproportionation of toluene; total toluene and trimethylbenzene conversion of 47.17%, selectivity to xylene of 83.25% and xylene yield of 39.26% were obtained for transalkylation.