制备条件对CoLa/Al2O3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/Al2O3 catalysts for ethanol dehydroamination to acetonitrile
李想 1冯超 2楚卫锋 2谢英鹏 3刘盛林 2朱向学2
作者信息
- 1. 沈阳化工大学 化学工程学院,辽宁 沈阳 110142;中国科学院 大连化学物理研究所,辽宁 大连 116023
- 2. 中国科学院 大连化学物理研究所,辽宁 大连 116023
- 3. 沈阳化工大学 化学工程学院,辽宁 沈阳 110142
- 折叠
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/Al2O3-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/Al2O3-10H2/N2的金属活性表面积先增加后下降,其中10Co0.25La/Al2O3-10H2/N2的还原态Co表面积为23.38 m2/g,其乙腈选择性最高(88.47%).保持其他反应条件不变,将10Co0.25La/Al2O3-10H2/N2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.
Abstract
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/Al2O3-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,N2 absorption/desorption and CO pulse chemisorption.The results show that the metal active surface area of xCo0.25La/Al2O3-10H2/N2 first increases and then decreases with the increase of Co loading,and the reduced Co surface area of 10Co0.25La/Al2O3-10H2/N2 is 23.38 m2/g,and its acetonitrile selectivity is the highest(88.47%).10Co0.25La/Al2O3-10H2/N2 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/Al2O3催化剂Key words
preparation conditions/ethanol dehydroamination/acetonitrile/CoLa/Al2O3 catalyst引用本文复制引用
基金项目
大连市重点领域创新团队项目(2020RT06)
大连化学物理研究所创新研究基金(DICPI202236)
出版年
2024
国家科技期刊平台
NSTL
万方数据