Zn对Cu-Zn-Al催化乙酸甲酯加氢反应的影响  

Effect of Zn on the Catalytic Performance of Cu-Zn-Al in the Hydrogenation of Methyl Acetate

作　　者：赵梓淇 车现坤 王志苗[1,2] 李芳 薛伟[1,2] 王延吉 ZHAO Ziqi;CHE Xiankun;WANG Zhimiao;LI Fang;XUE Wei;WANG Yanji(Hebei Provincial Key Laboratory of Green Chemical Technology and High Efficient Energy Saving,School of Chemical Engineering and Technology,Hebei University of Technology,Tianjin 300130,China;Tianjin Key Laboratory of Chemical Process Safety,Tianjin 300130,China)

机构地区：[1]河北工业大学化工学院河北省绿色化工与高效节能重点实验室,天津300130 [2]天津市本质安全化工技术重点实验室,天津300130

出　　处：《石油学报（石油加工）》2020年第1期45-53,共9页Acta Petrolei Sinica(Petroleum Processing Section)

基　　金：国家自然科学基金项目(21776057);天津市自然科学基金项目(17JCYBJC20100,18JCYBJC21500);河北省出国留学人员科技活动择优项目(CL201605)资助

摘　　要：采用共沉淀法制备Cu-Zn-Al催化剂,采用XRD、N 2等温吸附-脱附、SEM、H2-TPR、XPS和ICP-OES等手段对催化剂进行表征。结果发现,Zn的加入降低了Cu-Zn-Al催化剂颗粒的团聚程度,提高了活性中心Cu组分的分散度。并且Zn含量的改变可以影响Cu组分的价态分布,进而影响其催化性能。当n(Cu)/n(Zn)=2/3时,n(Cu^+)/n(Cu 0)为1.04,Cu-Zn-Al对乙酸甲酯(MA)加氢反应具有最优的催化性能。在反应温度为240℃、反应压力为3.0 MPa、n(H 2)/n(MA)=20的最优条件下,Cu-Zn-Al催化乙酸甲酯反应中乙酸甲酯转化率为98.8%,甲醇和乙醇选择性分别为99.4%和98.7%。对Cu-Zn-Al催化剂进行300 h寿命测试,乙酸甲酯转化率一直稳定在98%以上,甲醇和乙醇选择性则分别保持在99%和98%左右。Cu-Zn-Al catalysts were prepared by co-precipitation method and characterized by XRD,N2 isothermal adsorption-desorption,SEM,H2-TPR,XPS and ICP-OES.Results indicate that the agglomeration of catalyst particles is reduced by the addition of Zn,obtaining the highly dispersed Cu active sites.Furthermore,the valence of Cu species in Cu-Zn-Al catalysts was also changed with the increase of Zn content.When the molar ratio of Cu/Zn is 2/3,the molar ratio of Cu^+/Cu0 in the catalyst is 1.04 with a high activity in methyl acetate(MA)hydrogenation.The reaction conditions were optimized over Cu-Zn-Al catalyst with 2/3 of Cu/Zn molar ratio,as listed in following:reaction temperature of 240℃,reaction pressure of 3.0 MPa,and H 2/MA molar ratio of 20.Under the optimal conditions,MA conversion is 98.8%,and ethanol and methanol selectivity is 98.7%and 99.4%,respectively.Importantly,Cu-Zn-Al catalyst shows excellent catalytic activity and stability in MA hydrogenation reaction.After 300 h operation,MA conversion maintains more than 98%with the selectivity of ethanol and methanol above 98%and 99%,respectively.

关 键 词：乙醇 乙酸甲酯 加氢 Cu-Zn-Al催化剂 稳定性 

分 类 号：O643[理学—物理化学] X511[理学—化学]