金属改性纳米ZSM-5催化剂制备及异构化反应性能  

Metal-Modified Nano-ZSM-5 Catalyst and Its Performance for Isomerization Reaction

作　　者：李振忠 苗磊 程光剑 娄阳 赵国庆[2] 朱志荣[2] Li Zhenzhong;Miao Lei;Cheng Guangjian;Lou Yang;Zhao Guoqing;Zhu Zhirong(Research Institute of PetroChina Liaoyang Petrochemical Company,Liaoyang,Liaoning 111003,China;School of Chemical Science and Engineering,Tongji University,Shanghai 200092,China)

机构地区：[1]中国石油辽阳石化分公司研究院,辽宁辽阳111003 [2]同济大学化学科学与工程学院,上海200092

出　　处：《化学世界》2023年第1期51-56,共6页Chemical World

基　　金：国家自然科学基金面上(No.9153410105)资助项目。

摘　　要：采用浸渍-煅烧-还原方法对纳米级HZSM-5沸石进行了金属及氧化物改性研究,制备了Pt-Si-Mg-HZSM-5二甲苯异构化催化剂,并测试了催化剂的C_(8)混合芳烃(乙苯、间二甲苯和邻二甲苯)异构化反应的催化性能。反应结果表明:引入MgO修饰调节了HZSM-5催化剂的酸度分布,SiO_(2)的进一步沉积处理使HZSM-5孔口变窄和外表面酸位减少,提高了产物中对二甲苯(p-X)的收率,抑制了重芳烃(C(n(n≥9)))的形成。比较了金属Mo和Pt的负载对催化剂性能的影响,Mo的添加降低了二甲苯损失,但是其对二甲苯收率较低;Pt的负载增加了催化剂中乙苯的转化率,并且对催化剂的酸性位密度和强度几乎没有影响。催化剂在340℃低温下,对二甲苯收率为23.24%、乙苯转化率为46.01%、二甲苯损失的质量分数为2.35%。Metal and oxide modification of HZSM-5 nano-scale zeolite was studied by impregnation-calcination-reduction method so that Pt-Si-Mg-HZSM-5 xylene isomerization catalyst was prepared.Catalytic performance for the isomerization of aromatic hydrocarbons(ethylbenzene,m-xylene,and o-xylene)by Pt-Si-Mg-HZSM-5 was tested.The results showed that the introduction of MgO modulates the acidity distribution of HZSM-5 catalyst,and the further deposition of SiO2narrows the pores of HZSM-5 and reduces the acid sites on the outer surface,which improves the yield of paraxylene(p-X)and inhibits the formation of heavy aromatics(Cn(n≥9)).The effects of Mo and Pt loading on catalyst performance were compared.Mo addition reduced xylene loss while with a lower p-X yield;Pt loading increased the conversion of ethylbenzene without negative effect on the acid site density and strength.The p-X yield,EB conversion and xylene loss at 340℃were 23.24%,46.01%and 2.35%.

关 键 词：HZSM-5 二甲苯异构化C_(8) MgO二甲苯损失 

分 类 号：TQ241.13[化学工程—有机化工] TQ426