温度对β分子筛苯液相烷基化性能的影响  

Effects of temperature on the performance ofβmolecular sieve for liquid ethylation of benzene

作　　者：周玮 崔浪 赵江红 武建兵 王永钊[1] 赵永祥[1] Zhou Wei;Cui Lang;Zhao Jianghong;Wu Jianbing;Wang Yongzhao;Zhao Yongxiang(Engineering Research Center of Ministry of Education for Fine Chemicals,School of Chemistry and Chemical Engineering,Shanxi University,Taiyuan 030012,Shanxi,China)

机构地区：[1]山西大学化学化工学院,山西大学精细化学品教育部工程研究中心,山西太原030012

出　　处：《工业催化》2024年第2期69-75,共7页Industrial Catalysis

基　　金：国家自然科学基金项目(21776168);山西省重点研发计划项目(201903D121003);中央引导地方科技发展资金(YDZJSX2021A001);山西省科技重大专项项目(20181102019)。

摘　　要：温度对β分子筛催化苯与乙烯液相烷基化反应性能的影响较大,本文从催化剂及反应角度两方面研究了温度对催化剂性能的影响。通过X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)、N_(2)物理吸附-脱附(BET)及吡啶吸附傅里叶变换红外光谱(Py-FTIR)等方法对自制的β分子筛进行表征,并考察了不同温度下β分子筛在苯与乙烯液相烷基化反应中的催化性能。结果表明,随温度升高,乙烯转化率升高,乙苯选择性降低,二乙苯选择性增加,其中,邻二乙苯选择性降低,对二乙苯选择性增加。同时,随温度升高,β分子筛上B酸量减少,主要为桥式羟基B酸和端基硅羟基B酸的减少。表明反应温度对乙烯转化率的影响主要受动力学控制;而温度对产物选择性的影响主要来源于温度对B酸量变化的影响,其中,乙苯选择性与B酸量有正相关性,邻二乙苯选择性与桥式羟基B酸量和端基硅羟基B酸量有正相关性。Reaction temperature had a great influence on the catalytic performance ofβzeolite in the liquid phase alkylation reaction of benzene and ethylene.The effect of temperature on the performance of catalyst was studied in this paper from the catalyst and reaction’s point view.X-ray diffraction(XRD),scanning electron microscope(SEM),transmission electron microscopy(TEM),N_(2)physisorption-desorption(BET),and pyridine adsorption Fourier transform infrared spectroscopy(Py-FTIR)were used to characterize the self-madeβzeolite.And the effects of temperature on the catalytic performance ofβzeolite were also investigated.It was found that the conversion of ethylene increased and the selectivity of ethylbenzene decreased,while the selectivity of diethylbenzene increased with the rise of temperature.Thereof,the selectivity of o-diethylbenzene decreased and that of p-diethylbenzene increased.In addition,the increase of temperature led to the decrease of amount of B acid sites,mainly the decrease of bridged OH and terminal Si-OH groups.It was concluded that the effect of temperature on the conversion of ethylene was controlled by kinetics.The influence of temperature on the selectivity of the products mainly came from the influence of temperature on the change of contents of B acid.The selectivity of ethylbenzene was positively correlated with the amount of B-acid,and the selectivity of o-diethylbenzene was positively correlated with the amount of bridged OH and terminal Si-OH groups.

关 键 词：有机化学工程 温度 Β分子筛 乙苯 烷基化 转化率 选择性 

分 类 号：TQ241.11[化学工程—有机化工] O643.36[理学—物理化学]