VO_(x)/AlPO_(4)催化剂合成及其催化苯羟基化反应性能  

Synthesis of VO_(x)/AlPO_(4) catalyst and its catalytic performance in hydroxylation of benzene

作　　者：李贵贤[1] 李晗旭 田涛 李金莲 邵婷娜 董鹏[1] LI Guixian;LI Hanxu;TIAN Tao;LI Jinlian;SHAO Tingna;DONG Peng(School of Petrochemical Engineering,Langzhou University of Technology,Lanzhou 730050,Gansu,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：《精细化工》2023年第4期861-868,共8页Fine Chemicals

基　　金：甘肃省重大科技专项(19ZD2GD001)。

摘　　要：以异丙醇铝与磷酸为原料,离子液体1-丁基-3-甲基咪唑溴盐([Bmim]Br)与二正丙胺为共模板剂合成了Al PO_(4),进而采用水热法将V_(2)O_(5)负载于Al PO_(4)载体制备了VO_(x)/Al PO_(4)催化剂。采用XRD、SEM、TEM、Mapping、FTIR、N_(2)吸附-脱附、XPS对催化剂进行了表征,考察了其在苯羟基化反应中的催化性能。结果表明,钒氧化物负载量为16%(以V_(2)O_(5)和Al PO_(4)的总质量为基准,下同)的催化剂具有最多且分布均匀的V4+活性中心、契合反应的酸性微环境,在催化剂用量为0.2 g,苯用量4 mL,质量分数30%的H2O2用量12.5 mL,乙腈用量15 mL,反应温度70℃,反应时间7 h的条件下,苯转化率为53.4%,苯酚选择性为98.4%。基于催化剂表征分析及性能评估,推测催化反应机理是以亲核氧化机理为主,自由基机理为辅。A series of VO_(x)/AlPO_(4) catalysts were synthesized from V_(2)O_(5) and carrier AlPO_(4),which was prepared from aluminum isopropanol and phosphoric acid using ionic liquid[Bmim]Br and di-n-propylamine as co-template.The catalysts obtained were then characterized by XRD,SEM,TEM,Mapping,FTIR,N_(2) adsorption-desorption and XPS,and evaluated for their catalytic performance in benzene hydroxylation.The results showed that the catalyst with a vanadium oxide loading of 16%(based on the total mass of V_(2)O_(5) and AlPO_(4),the same below)displayed the most uniformly distributed V4+active centers,an acidic microenvironment suitable for the reaction.Under the conditions of catalyst dosage 0.2 g,benzene 4 mL,hydrogen peroxide with a mass fraction of 30%12.5 mL,acetonitrile 15 mL,reaction temperature 70℃and reaction time 7 h,the conversion rate of benzene was 53.4%and the selectivity of phenol reached 98.4%.Data from catalyst characterization and performance evaluation suggested that the reaction was mainly catalyzed by nucleophilic oxidation,complemented by free radical mechanism.

关 键 词：VO_(x)/Al PO_(4) 苯 苯酚 羟化 自由基 催化技术 

分 类 号：O643.37[理学—物理化学] TQ243.12[理学—化学]