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采用USY分子筛催化剂气相催化甲苯与叔丁醇的烷基化反应。利用NH3-TPD、XRD、BET等方法对催化剂进行表征,探讨了氢化及水热改性处理对催化剂结构及物性参数的影响。考察了反应条件对该烷基化反应甲苯转化率和PTBT选择性的影响,和改性处理对催化剂催化性能的影响。实验结果表明,氢化及水热处理并未改变其结构,但微孔数量降低,比表面积下降。氢化后USY的酸性增强,水热处理后酸性略有增加。氢化及水热处理对催化性能提高3%~5%,同时提高了催化剂的稳定性和有效使用寿命。在反应温度120℃,空速1 h~(-1),甲苯/叔丁醇为2的条件下,反应45 h内甲苯转化率维持在30%左右,PTBT选择性高于80%。
USY Molecular Sieve Catalysts for Catalytic Alkylation of Toluene with tert-Butyl Alcohol. The catalysts were characterized by NH3-TPD, XRD and BET methods. The effects of hydrogenation and hydrothermal treatment on the structure and physical properties of the catalyst were discussed. The effects of reaction conditions on the conversion of toluene and PTBT selectivity of the alkylation reaction and the effect of the modification on the catalytic performance of the catalyst were investigated. The experimental results show that hydrogenation and hydrothermal treatment did not change its structure, but the number of micropores decreased, the specific surface area decreased. The acidity of USY after hydrogenation is enhanced, and the acidity is slightly increased after hydrothermal treatment. Hydrogenation and hydrothermal treatment of the catalytic performance increased by 3% to 5%, while improving catalyst stability and effective service life. Under the conditions of reaction temperature of 120 ℃, space velocity of 1 h -1 and toluene / tert-butyl alcohol of 2, the conversion of toluene was maintained at 30% within 45 h and the selectivity of PTBT was above 80%.