摘要
研究了在温和反应条件下自制的ＴＳ－１分子筛催化苯羟基化的反应规律．着重考察了酸介质的影响和溶剂的作用，发现在水相和有机相中苯的羟基化和苯酚的进一步羟基化具有不同的规律，有机相中苯的羟基化是主要反应，水相中的主要反应是中间产物苯酚的进一步羟基化，溶剂的作用则是使苯和双氧水分子在ＴＳ－１分子筛表面上充分接触并发生反应．发现以丙酮为溶剂，采用乙酸或乙酸酐作介质，较之硫酸介质能更有效地提高苯的转化率；同中性介质相比，苯转化率提高了３２％；同硫酸相比，苯转化率提高了１５％，苯酚选择性提高了４５％．此外，还考察了反应温度、反应时间等其它因素对苯羟基化反应的影响，并在实验基础上推测了ＴＳ－１分子筛催化苯羟基化的反应机理．
おhe hydroxylation of benzene with H_2O_2 under mild conditions over zeolite TS1 was studied. The result showed that the hydroxylation of benzene and the further hydroxylation of phenol in organic phase are different from that in aqueous phase. The hydroxylation of benzene takes place mostly in organic phase and the hydroxylation of phenol mostly in the aqueous phase. The addition of solvent helps benzene to efficiently contact with H2O2 on the surface of zeolite TS1. It was found that in the presence of acetone used as a solvent, acetic acid or acetic anhydride is more favorable for benzene hydroxylation than sulfuric acid, with benzene conversion and phenol selectivity increased by 15% and 45% respectively. In addition, the influences of other reaction factors such as the reaction temperature and the reaction time were also examined. The mechanism of benzene hydroxylation was discussed.
出处
《分子催化》
EI
CAS
CSCD
北大核心
1998年第1期48-52,共5页
Journal of Molecular Catalysis(China)
关键词
TS-1
分子筛
苯
苯酚
羟基化
Zeolite TS1, Benzene, Phenol, Hydroxylation
