通过简单的酸碱中和法制备出一系列碳链长度不同的杂多酸有机盐催化剂,在苯与双氧水羟基化制苯酚的反应中比较了催化剂的性能,发现钼钒磷杂多酸三乙胺盐的活性最高。随后在该催化剂上研究了苯与双氧水羟基化制苯酚的本征动力学。结果表明,在消除内外扩散影响的前提下,该反应对于苯和双氧水的反应级数都为1级,反应活化能为93.3 kJ mol 1。研究工作为苯与双氧水羟基化制苯酚的过程开发提供了基础。
A serial of organic molybdovanadophosphoric heteropolyacid salt catalysts with different organic carbon-chain lengths were prepared by a facile acid-base neutralization method, and then a comparison was made for their catalytic activities in the reaction of hydroxylation of benzene to phenol with hydrogen peroxide as oxidant. The results show that the triethylamine molybdovanadophosphoric heteropolyacid salt (TEA-PMoV) has the highest catalytic activity for the hydroxylation reaction. Additionally, the intrinsic kinetics of the hydroxylation of benzene to phenol with hydrogen peroxide over TEA-PMoV was systematically investigated, from which both the orders of reaction with respect to benzene and hydrogen peroxide were found to be first order and the activation energy is 93.3 kJ.mol^-1, when the internal and external diffusion limitations are excluded. The obtained kinetic data are essential for the process development of the hydroxylation of benzene with hydrogen peroxide over the TEA-PMoV catalyst.