镧改性Cu/SiO_(2)催化剂的乙酸甲酯高效加氢催化性能研究  

Catalytic performance of La-modified Cu/SiO_(2) in the hydrogenation of methyl acetate

作　　者：张传明 李伟杰 康金灿[1] 林丽娜 李昌鑫 李林才 邹昊宇 朱红平[1] ZHANG Chuanming;LI Weijie;KANG Jincan;LIN Lina;LI Changxin;LI Lincai;ZOU Haoyu;ZHU Hongping(State Key Laboratory of Physical Chemistry of Solid Surfaces,National Engineering Laboratory for Green Chemical Productions of Alcohols-Ethers-Esters,College of Chemistry and Chemical Engineering,Xiamen University,Xiamen 361005,China)

机构地区：[1]厦门大学化学化工学院固体表面物理化学国家重点实验室醇醚酯化工清洁生产国家工程实验室,福建厦门361005

出　　处：《燃料化学学报（中英文）》2024年第2期131-139,共9页Journal of Fuel Chemistry and Technology

基　　金：国家自然科学基金(21972112,22172123);福建省高校产学合作项目(2021H6002)资助。

摘　　要：采用蒸氨法制备了镧(La)改性的负载型铜硅(Cu/SiO_(2))催化剂,并对其乙酸甲酯(MeOAc)气相加氢制乙醇(EtOH)的催化性能进行了研究。采用N2吸附-脱附(N2adsorption-desorption)、X射线粉末衍射(XRD)、电感耦合等离子体发射光谱(ICP-OES)、氢气程序升温还原(H2-TPR)、傅里叶红外光谱(FT-IR)、高分辨透射电镜(HRTEM)、光电子能谱(XPS)和原子发射光谱仪(AES)等手段对催化剂进行了的表征,发现La物种的加入产生了较多的层状硅酸铜,增强了Cu和La物种之间的相互作用。La物种的加入在结构方面提高了催化剂的比表面积,降低了铜物种的粒径,提高了铜物种的分散度;在电子还原调控方面提高了Cu+的含量,增强了催化剂吸附酰基和甲氧基的能力。与未改性的Cu/SiO_(2)催化剂相比,镧改性后Cu/SiO_(2)催化剂的乙酸甲酯加氢性能得到大幅提升;其中La掺杂量0.5%的Cu/SiO_(2)催化剂表现出最佳的催化性能,乙酸甲酯转化率达98.5%,乙醇的总收率为97.0%。A series of Cu/SiO_(2) catalysts modified with lanthanum(La)(30Cu-nLa/SiO_(2),n=0,0.5,1 and 2)were synthesized using the ethanol(EtOH)-assisted ammonia-evaporation method;their catalytic performance in the gas-phase hydrogenation of methyl acetate(MeOAc)to produce ethanol(EtOH)was investigated.The results indicate that the catalytic performance of Cu/SiO_(2) can be greatly enhanced by La modification.In particular,the 30Cu-0.5La/SiO_(2) catalyst exhibits excellent performance in the MeOAc hydrogenation;under 230°C,2 MPa H2,an LHSV of 2 h−1 and an H2/MeOAc molar ratio of 20,the MeOAc conversion reaches 98.5%,with a total EtOH yield of 97.0%.The N2-sorption,XRD,ICP-OES,H2-TPR,FT-IR,TEM,XPS,and AES characterization results reveal that the introduced La metal has a strong interaction with Cu,which can promote the dispersion of the copper species on the SiO_(2) support.Moreover,the content of Cu+is increased significantly,which can enhance the electronic interaction with MeOAc via the acyl and methoxide groups and thus promote the hydrogenation of MeOAc to EtOH.

关 键 词：乙酸甲酯 加氢 乙醇 Cu/SiO_(2) La改性 

分 类 号：O643.38[理学—物理化学]