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对添加不同造孔剂用量挤条成型的HZSM-5分子筛,通过浸渍法制备了金属-非金属复合改性的催化剂,采用X射线衍射(XRD)、压汞法等手段对催化剂的结构进行了表征,在固定床等温反应器上考察了HZSM-5分子筛催化剂在甲苯与甲醇烷基化反应中的性能.结果表明,在温度为540℃、压力为0.5 MPa、质量空速为2 h~(-1)、n(甲醇):n(甲苯)=1:2、n(甲苯+甲醇):n(H_2O):n(H_2)=1:1.3:4的优化反应条件下,高造孔剂用量的HZSM-5分子筛催化剂上甲苯转化率达28%~34%,对二甲苯在二甲苯异构体中的选择性为92%~96%,单程稳定运行超过1200 h.活性下降的催化剂经原位再生后性能基本恢复,并通过N2吸附、热重分析(TG-DTG)、氨气-程序升温脱附(NH3-TPD)、拉曼光谱(Raman)、紫外-可见分光光谱(UV-Vis)和核磁共振(NMR)等手段对反应前后的催化剂进行了表征.
For the HZSM-5 molecular sieve with different pore-forming agents, the metal-nonmetal composite modified catalyst was prepared by impregnation method. The structure of the catalyst was characterized by X-ray diffraction (XRD) and mercury intrusion porosimetry HZSM-5 molecular sieve catalyst was investigated in a fixed-bed isothermal reactor.The results showed that at a temperature of 540 ℃, a pressure of 0.5 MPa and a mass space velocity of 2 h ~ ( Under the optimal reaction conditions of n (methanol): n (toluene) = 1: 2 and n (toluene + methanol): n (H 2 O): n (H 2) = 1: 1.3: 4, The conversion of toluene over the HZSM-5 zeolite catalyst was 28% -34%, that of para-xylene was 92% -96%, and that of the xylene was more than 1200 h. After in-situ regeneration, the performance was basically restored. The products were characterized by N2 adsorption, TG-DTG, NH3-TPD, Raman and UV- Vis and nuclear magnetic resonance (NMR) were used to characterize the catalysts before and after the reaction.