季铵盐相转移催化氧化噻吩的研究

以噻吩的正庚烷溶液模拟轻质油品,研究了H2O2—HCOOH氧化条件下，相转移催化氧化噻吩脱硫。实验结果表明，四丁基溴化铵用量0.10g，反应1.5h，反应温度45℃，脱硫率最高可达86.36%。动力学研究表明，以四丁基溴化铵作为相转移催化剂，过氧化氢 甲酸氧化噻吩脱硫为表观一级反应，反应速率常数 K30℃=0.6152h-1、K40℃=1.2672h-1、K50℃=0.8581h-1；相转移催化在H2O2—有机酸体系氧化噻吩脱硫反应中的作用为相转移催化剂阳离子Q+对氧化剂活性组分HCOOO－的转移作用。并建立了相转移催化氧化噻吩脱硫反应的循环模型。

Study of oxidative desulfurization of thiophene by phase transfer catalysis

Oxidative desulfurization of thiophene by phase transfer catalysis has been investigated with hydrogen peroxide formic acid as the oxidant, thiophene in n heptane as model compound of light oil. It was shown that the desulfurization rate of thiophene was 86.36%, under the conditions of water/oil ratio being 1∶1, after1.5h at temperature of 45℃ by TBAB. From the kinetics investigation, it was shown that when the model compound was oxidized by hydrogen peroxide formic acid with TBAB as phase transfer catalyst, the reaction was pseudo first order reaction with rate constants of K30℃=0.6152h-1, K40℃=1.2672h-1, and K50℃=0.8581h-1. The essential process of catalytic oxidation is the transfer of oxidizing active ingredients RCOOO- from water phase to oil phase by Q+, and the cycling models of oxidative desulfurization of thiophene by phase transfer catalysis(Q+X-) is builted.