超细Fe-ZSM-5分子筛的原位合成及其甲醇制丙烯性能  

In-situ synthesis of ultrafine Fe-ZSM-5 zeolite for methanol to propylene(MTP)reaction

作　　者：王有和[1] 李晨灿 代畅 臧金龙 杜宁宁 毛雨馨 阎子峰[1] WANG Youhe;LI Chencan;DAI Chang;ZANG Jinlong;DU Ningning;MAO Yuxin;YAN Zifeng(State Key Laboratory for Heavy Oil Processing in China University of Petroleum(East China),Qingdao 266580,China;Shandong High-End Chemical Research Institute,Heze 274002,China)

机构地区：[1]中国石油大学(华东)重质油国家重点实验室,山东青岛266580 [2]山东高端化工研究院,山东菏泽274002

出　　处：《中国石油大学学报(自然科学版)》2023年第6期178-184,共7页Journal of China University of Petroleum(Edition of Natural Science)

基　　金：国家自然科学基金项目(21776311);中央高校基本科研业务费专项(22CX03001A);山东省自然科学基金项目(ZR2023MB101);山东省泰山学者攀登计划项目(tspd20210308);大学生创新创业训练项目(S202110425026)。

摘　　要：采用干凝胶法原位合成出颗粒粒径约为50~120 nm且含骨架杂原子的超细Fe-ZSM-5分子筛,利用X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)、紫外-可见光光谱仪(UV-Vis)、氨的程序升温脱附(NH3-TPD)、吡啶吸附红外光谱(Py-FT-IR)和N2吸附-脱附等手段对样品进行表征。结果表明:原位添加的Fe源不仅可以降低分子筛颗粒粒径,还能降低分子筛酸强度;原位合成的Fe-ZSM-5分子筛中Fe物种主要以四配位骨架Fe3+存在,其余以低聚的FeOx以及Fe2O3颗粒存在,而浸渍法制备的Fe/ZSM-5分子筛中Fe物种主要以后2种形式存在;Fe改性调变了ZSM-5分子筛的酸性质,从而提高了MTP反应产物丙烯的选择性;与负载型Fe/ZSM-5分子筛催化剂相比,原位改性的含骨架杂原子超细Fe-ZSM-5分子筛催化剂由于具有更小的晶粒粒径和适宜的酸性质,从而进一步提高了丙烯选择性。Ultrafine Fe-ZSM-5 zeolite containing framework heteroatoms with around 50-120 nm in diameter was successfully in-situ synthesized via a dry gel conversion method.The fabricated samples were characterized by means of XRD,SEM,TEM,UV-Vis,NH3-TPD,Py-FT-IR and N2 adsorption-desorption isotherms.The results indicate that Fe source added in-situ can not only reduce the size of zeolite particles,but also reduce the acid strength of zeolite.Ultrafine Fe-ZSM-5 zeolite prepared by in-situ synthesis method contains three kinds of Fe species,and most of Fe attributes to isolated framework Fe^(3+)species in tetrahedral coordination and the rest exists as oligomerized FeOx and Fe2O3 particles.But Fe/ZSM-5 zeolite pre-pared by impregnation method mainly contains latter two forms of Fe species with a little of Fe3+in the framework of the zeo-lite.The acid properties of ZSM-5 zeolite were modified by Fe modification,which improved the selectivity of propylene in MTP reaction.Compared to the Fe/ZSM-5 zeolite fabricated by traditional impregnation method,the in-situ synthesized ul-trafine Fe-ZSM-5 zeolite containing framework heteroatoms presents higher propylene selectivity in the MTP process due to smaller grain size and more suitable acid properties.

关 键 词：超细Fe-ZSM-5分子筛 干凝胶法 原位合成 甲醇制丙烯 

分 类 号：O611.4[理学—无机化学]