采用低温陈化法制备S₂O_2-8/SnO₂-Al₂O₃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NH₃-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 m²/g)、总酸量更高(142.9 μmol/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%。

S₂O_2-8/SnO₂-Al₂O₃ 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 m²·g^-1),and higher total acid content (142.9 μmol·g^-1).The yield of methyl L-tyrosine reaches 92% after the esterification reaction between L-tyrosine and methanol over the S₂O_2-8/SnO₂-Al₂O₃ modified by radio frequency plasma has performed for 6 h at 180℃,1 MPa.

张旭东(1999-),男,硕士生,研究方向为固体超强酸催化剂,onlyfaith44@163.com;李秀兰(1977-),女,博士,副教授,研究方向为金属表面改性,通讯联系人,hhqlxl@163.com;朱文超(1981-),男,博士,副研究员,研究方向为等离子体化学化工,通讯联系人,zhuwc05@139.com。