纳米Au-CoO_x催化剂的制备及其催化甲基酯化法制备甲基丙烯酸甲酯动力学研究  

Preparation of nanometer Au-CoO_x catalyst and kinetic study on catalytic methyl esterification over it to prepare methyl methacrylate

作　　者：李国松[1] 王连月[1] 张毅[1] 李文双 姜叶薇 高爽[1] Li Guosong;Wang Lianyue;Zhang Yi;Li Wenshuang;Jiang Yewei;Gao Shuang(Dalian Institute of Chemical Physics,Chinese Academy of Science,Dalian Liaoning 116023,China;Chia Tai Energy Materials(Dalian)Co.Ltd.,Dalian Liaoning 116023,China)

机构地区：[1]中国科学院大连化学物理研究所,辽宁大连116023 [2]正大能源材料(大连)有限公司,辽宁大连116023

出　　处：《石油化工》2018年第9期969-975,共7页Petrochemical Technology

基　　金：国家自然科学基金资助项目(21403219;21773227;21773232)

摘　　要：制备了Au-CoO_x负载型催化剂,采用SEM、TEM、XRD、N_2吸附-脱附等手段对催化剂进行表征,并将其用于甲基丙烯醛一步氧化酯化制备甲基丙烯酸甲酯的反应中,考察了反应温度、压力、重时空速、醇醛质量比、空气流量等条件对反应的影响,研究了反应的固定床反应动力学。实验结果表明,所制备催化剂颗粒除少量破损外,形貌均为光滑的小球状,AuCoO_x复合纳米粒子在载体上分布较均匀,催化剂制备过程中Au与Co的引入对载体的结构基本无影响;使用该催化剂在重时空速0.8 h^(-1)、反应温度80℃、反应压力2.5 MPa、醇醛质量比11∶1、空气流量20mL/min条件下,实验连续运行1000 h后,甲基丙烯醛的转化率仍达90%,甲基丙烯酸甲酯的选择性基本保持不变。A new Au-CoOx supported catalyst was prepared and characterized by SEM,TEM,XRD and N2 adsorption-desorption.The catalyst was used in the one-step oxidative esterifi cation of methacrolein to methyl methacrylate.The effects of reaction temperature,pressure,weight hourly space velocity,mass ratio of methanol to methacrylaldehyde and air fl ow rate on the reaction were studied,and the reaction kinetics of the fi xed bed was investigated.The experimental results showed that the morphology of the prepared catalyst particles was smooth and small globular with very small amount of damage.The distribution of Au-CoOx composite nanoparticles on the support was uniform.The introduction of Au and Co in the preparation of the catalyst had seldom effect on the support structure.The selectivity of methyl methacrylate remained basically unchanged by using this catalyst under the conditions of heavy hourly space velocity 0.8 h-1,reaction temperature 80℃,reaction pressure 2.5 MPa,mass ratio of methanol to methacrylaldehyde 11∶1,air fl ow rate 20 mL/min,continuous operation for 1 000 h,and the conversion rate of methacrylaldehyde was still 90%.

关 键 词：甲基丙烯醛 氧化酯化 甲基丙烯酸甲酯 动力学 

分 类 号：TQ426.94[化学工程]