改性纳米HZSM-5催化剂上甲苯与甲醇的烷基化反应  

Shape-Selective Alkylation of Toluene with Methanol over Modified Nano-scale HZSM-5 Zeolite

作　　者：张志萍[1] 赵岩[1] 吴宏宇[1] 谭伟[1] 王祥生[1] 郭新闻[1] 

机构地区：[1]大连理工大学化工学院催化化学与工程系,精细化工国家重点实验室,辽宁大连116024

出　　处：《催化学报》2011年第7期1280-1286,共7页

摘　　要：以Si,P,Mg复合改性的纳米HZSM-5为催化剂,进行了甲苯与甲醇的烷基化反应;并采用X射线衍射,NH3程序升温脱附,红外和低温N2吸附等方法研究了改性前后催化剂酸性质和孔结构的变化.在小型固定床反应器上,考察了载气量、反应温度和重时空速等反应条件对烷基化反应性能的影响.在2h–1,460oC,甲苯/甲醇比,水/烃比和N2/烃摩尔比均为8的优化条件下,单程连续运转500h,甲苯转化率可维持在10%左右,对二甲苯选择性高于97%,催化剂表现出良好的稳定性.Shape-selective alkylation of toluene（T） with methanol（M） was performed over Si-P-Mg-modified nano-scale HZSM-5 zeolite. The change of acidity and pore structure of the catalyst was studied by X-ray diffraction,NH3 temperature-programmed desorption,Fourier transform infrared spectroscopy,and N2 adsorption.The effects of temperature,space velocity（WHSV） ,and flow rate of N2 carrier gas on the reaction were investigated in a continuous flow fixed-bed reactor. Under the optimized conditions（2 h–1,460 oC,n（T） /n（M） = n（H2O） /n（HC） = n（N2） /n（HC） = 8,where HC represents toluene and methanol） ,during 500 h on stream over the Si-P-Mg modified nano-scale HZSM-5 catalyst,the toluene conversion of about 10% and the selectivity to p-xylene of more than 97% were maintained,indi-cating that the catalyst exhibits high selectivity and good stability.

关 键 词：纳米HZSM-5分子筛 硅-磷-镁复合改性 甲苯 甲醇 烷基化 对二甲苯 

分 类 号：TQ203.2[化学工程—有机化工]