制备条件对CoLa/Al_(2)O_(3)催化剂上乙醇脱氢氨化制乙腈反应性能的影响  

Effects of preparation conditions on reaction performances of CoLa/Al_(2)O_(3) catalysts for ethanol dehydroamination to acetonitrile

作　　者：李想 冯超 楚卫锋 谢英鹏 刘盛林[2] 朱向学[2] LI Xiang;FENG Chao;CHU Weifeng;XIE Yingpeng;LIU Shenglin;ZHU Xiangxue(School of Chemical Engineering,Shenyang University of Chemical Technology,Shenyang 110142,Liaoning,China;Dalian Institute of Chemical Physics,Chinese Academy of Sciences,Dalian 116023,Liaoning,China)

机构地区：[1]沈阳化工大学化学工程学院,辽宁沈阳110142 [2]中国科学院大连化学物理研究所,辽宁大连116023

出　　处：《低碳化学与化工》2024年第5期28-35,共8页Low-Carbon Chemistry and Chemical Engineering

基　　金：大连市重点领域创新团队(2020RT06);大连化学物理研究所创新研究基金(DICPI202236)。

摘　　要：乙醇脱氢氨化法是获得高纯度乙腈较为清洁、安全和经济的途径。在固定床反应器上考察了制备条件(焙烧气氛和Co负载量)对xCo0.25La/Al_(2)O_(3)-y(x和0.25分别代表Co和La的负载量(质量分数,%),y代表焙烧气氛)的乙醇脱氢氨化制乙腈反应(在410℃、0.1 MPa、无水乙醇空速0.5 h^(-1)、氨与醇物质的量之比为6:1的条件下反应45 min)催化性能的影响,采用XRD、XRF、N2物理吸/脱附和CO脉冲化学吸附等对催化剂进行了表征。结果表明,随着Co负载量的增加,xCo0.25La/Al_(2)O_(3)-10H_(2)/N_(2)的金属活性表面积先增加后下降,其中10Co0.25La/Al_(2)O_(3)-10H_(2)/N_(2)的还原态Co表面积为23.38 m^(2)/g,其乙腈选择性最高(88.47%)。保持其他反应条件不变,将10Co0.25La/Al_(2)O_(3)-10H_(2)/N_(2)在430℃下连续运转120 h,乙腈选择性由初始的88.32%快速下降到21 h的66.80%,随后稳定在65%左右,相应乙胺选择性和丁腈选择性分别维持在12%左右和5%左右。Ethanol dehydroamination is a clean,safe and economical way to obtain high purity acetonitrile.The effects of preparation conditions(calcination atmospheres and Co loadings)on the catalytic performances in ethanol dehydroamination to acetonitrile over xCo0.25La/Al_(2)O_(3)-y(x and 0.25 represent the loading(mass fraction,%)of Co and La,respectively,and y represents calcination atmospheres)were investigated in a fixed flow bed.And the reactions were carried out for 45 min at 410℃0.1 MPa,anhydrous ethanol space velocity of 0.5 h^(-1),and the ratio of ammonia to alcohol of 6:1.The catalysts were characterized by XRD,XRF,N_(2)absorption/desorption and CO pulse chemisorption.The results show that the metal active surface area of xCo0.25La/Al_(2)O_(3)-10H_(2)/N_(2)first increases and then decreases with the increase of Co loading,and the reduced Co surface area of 10Co0.25La/Al_(2)O_(3)-10H_(2)/N_(2)is 23.38 m^(2)/g,and its acetonitrile selectivity is the highest(88.47%).10Co0.25La/Al_(2)O_(3)-10H_(2)/N_(2)is continuously operated at 430℃for 120 h while other reaction conditions unchanged,and the acetonitrile selectivity rapidly decreases from the initial 88.32%to 66.80%at 21 h,and then satabilizes at about 65%.The corresponding selectivity of ethylamine and butyronitrile remain about 12%and 5%,respectively.

关 键 词：制备条件 乙醇脱氢氨化 乙腈 CoLa/Al_(2)O_(3)催化剂 

分 类 号：TQ426[化学工程] O643.3[理学—物理化学]