射频等离子体改性制备S_(2)O_(2)-8/SnO_(2)-Al_(2)O_(3)固体超强酸催化剂的研究  

Preparation of S_(2)O_(2)-8/SnO_(2)-Al_(2)O_(3) solid superacid catalyst via radio frequency plasma modification

作　　者：张旭东 李秀兰 朱长辉 田保河 朱文超 ZHANG Xu-dong;LI Xiu-lan;ZHU Chang-hui;TIAN Bao-he;ZHU Wen-chao(School of Mechanical Engineering,Sichuan University of Science and Engineering,Yibin 644005,China;State Key Laboratory of NBC Protection for Civilian,Beijing 102205,China)

机构地区：[1]四川轻化工大学机械工程学院,四川宜宾644005 [2]国民核生化灾害防护国家重点实验室,北京102205

出　　处：《现代化工》2024年第7期139-144,共6页Modern Chemical Industry

基　　金：四川省科技计划资助项目(2022YFG0289);自贡市科技局重点科技计划项目(2018YYJC08);四川轻化工大学人才引进项目(2018RCL12)。

摘　　要：采用低温陈化法制备S_(2)O_(2)-8/SnO_(2)-Al_(2)O_(3)固体超强酸催化剂,利用射频等离子体技术对其进行改性后催化L-酪氨酸与甲醇的酯化反应。利用Hammett指示剂法、XRD、HRTEM、BET、FT-IR、Py-IR和NH_(3)-TPD等对改性前后的催化剂进行表征。结果表明,经射频等离子体改性后的催化剂颗粒分散性更好、粒径更小(4.32 nm)、比表面积更大(104.4 m^(2)/g)、总酸量更高(142.9μmol/g)。在温度为180℃、压力为1 MPa的条件下,射频等离子体改性后的催化剂催化L-酪氨酸甲酯化反应6 h后L-酪氨酸甲酯产率可达92%。S_(2)O_(2)-8/SnO_(2)-Al_(2)O_(3) solid superacid catalyst is prepared through a low temperature aging method,modified by radio frequency plasma technology and used for the esterification reaction between L-tyrosine and methanol.The catalysts before and after modification are characterized by means of Hammett indicator method,XRD,HRTEM,BET,FT-IR,Py-IR and NH3-TPD.The results show that compared with the catalyst before modification,the catalyst modified by radio frequency plasma has more uniform particle distribution,smaller average particle size(4.32 nm),larger specific surface area(104.4 m^(2)·g^(-1)),and higher total acid content(142.9μmol·g^(-1)).The yield of methyl L-tyrosine reaches 92%after the esterification reaction between L-tyrosine and methanol over the S_(2)O_(2)-8/SnO_(2)-Al_(2)O_(3) modified by radio frequency plasma has performed for 6 h at 180℃,1 MPa.

关 键 词：固体超强酸 S_(2)O_(2)-8/SnO_(2)-Al_(2)O_(3) 射频等离子体 酯化反应 

分 类 号：O69[理学—化学]