VO_(x)/SiO_(2)-Al_(2)O_(3)催化剂催化苯羟基化制苯酚  

Catalytic Hydroxylation of Benzene to Phenol with VO_(x)/SiO_(2)-Al_(2)O_(3) Catalyst

作　　者：李贵贤[1] 李延伟 李晗旭 祁建军 张军强 董鹏[1] LI Gui-xian;LI Yan-wei;LI Han-xu;QI Jian-jun;ZHANG Jun-qiang;DONG Peng(School of Petrochemical Engineering,Lanzhou University of Technology,Lanzhou 730050,China)

机构地区：[1]兰州理工大学石油化工学院,甘肃兰州730050

出　　处：《分子催化》2021年第5期440-448,I0002,共10页Journal of Molecular Catalysis(China)

基　　金：甘肃省科技计划项目(20JR10RA190)。

摘　　要：以硅溶胶和偏铝酸钠合成的SiO_(2)-Al_(2)O_(3)复合氧化物作为载体,并采用水热合成法合成了 VO_(x)/SiO_(2)-Al_(2)O_(3)催化剂.采用XRD、SEM、TEM、XPS、NH_(3)-TPD、N_(2)物理吸/脱附等技术对样品进行了表征.由XRD、SEM和TEM表征结果可知,活性中心钒能够被均匀分散于SiO_(2)-Al_(2)O_(3)复合氧化物的表面;由XPS及NH_(3)-TPD表征发现,当钒的含量为4%时催化剂中V^(4+)含量最大且总酸量相对适中.探究了 VO_(x)/SiO_(2)-Al_(2)O_(3)催化剂对苯羟基化制苯酚反应的催化性能,结果表明:相对于其他催化剂,由于4%VO_(x)/SiO_(2)-Al_(2)O_(3)催化剂拥有高分散活性中心、最大的V^(4+)含量及适中的载体酸性环境等微观结构而表现出良好的催化性能,苯转化率为48.1%,苯酚选择性为99.6%.SiO_(2)-Al_(2)O_(3)composite oxide was synthesized by silica sol and sodium metaluminate and VO_(x)/SiO_(2)-Al_(2)O_(3)catalyst was synthesized by hydrothermal method using SiO_(2)-Al_(2)O_(3)composite oxide as support.The samples were characterized by XRD,SEM,TEM,XPS,NH_(3)-TPD and N_(2)physical adsorption/desorption.The results of XRD,SEM and TEM showed that the active center vanadium was highly dispersed on the surface of SiO_(2)-Al_(2)O_(3)composite oxide.By XPS and NH_(3)-TPD characterization,it was found that when the content of vanadium was 4%,the content of V^(4+)in the catalyst reached the maximum and the total acid content was relatively moderate.The catalytic performance of VO_(x)/SiO_(2)-Al_(2)O_(3)catalyst for hydroxylation of benzene to phenol was investigated.Compared with other catalysts,the results showed that the 4%VO_(x)/SiO_(2)-Al_(2)O_(3)catalyst showed good catalytic performance,that is,the conversion of benzene was 48.1%and the selectivity of phenol was 99.6%,which was based on a high dispersed active center,the largest content of V^(4+)and moderate acidic environment of the carrier in 4%VO_(x)/SiO_(2)-Al_(2)O_(3)catalyst.

关 键 词：VO_(x)/SiO_(2)-Al_(2)O_(3)催化剂 苯 苯酚 羟基化 

分 类 号：O643.32[理学—物理化学]