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以硅溶胶、硫酸铝、氢氧化钠、四丙基溴化铵以及硼酸和九水硝酸铁为原料,采用EU-1晶种,通过水热法合成了2种含杂原子的微孔结构ZSM-5/EU-1复合分子筛.采用XRD、SEM、N2吸附-脱附和NH3-TPD对合成样品进行了表征,并在连续流动固定床反应器上考察了该分子筛催化剂对甲醇制二甲苯反应的催化性能.结果表明:含杂原子微孔结构的ZSM-5/EU-1复合分子筛同时具有ZSM-5和EU-1的特征衍射峰,结晶度较好,平均孔径明显增大,当催化剂的酸强度和酸量增大时,有利于甲醇芳构化趋势以及二甲苯优先扩散.B-ZSM-5/EU-1催化产物中芳烃在油相中的选择性达到84.70%; B-ZSM-5/EU-1和Fe-ZSM-5/EU-1两种分子筛催化产物的芳香烃中二甲苯的含量最高,分别为41.32%~45.88%和33.88%~39.16%.由于B-ZSM-5/EU-1较高的酸性、酸量和相对较小的孔道内径(0.8060 nm),较Fe-ZSM-5/EU-1更有利于产物中二甲苯的生成;不仅如此,B-ZSM-5/EU-1复合分子筛催化产物中对二甲苯在二甲苯中选择性范围为29.75%~47.47%;不过,Fe-ZSM-5/EU-1产物中对二甲苯在二甲苯中的含量最高可达53.75%,这是由于Fe-ZSM-5/EU-1复合分子筛的粒径较大,为催化反应提供了较长的孔道结构,易使产物中邻、间二甲苯在扩散过程中异构化转化为对二甲苯的缘故.

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