季铵盐相转移催化氧化噻吩脱硫的研究

Study of Oxidative Desulfurization of Thiophene by Phase Transfer Catalysis

在验证季铵盐相转移催化氧化噻吩脱硫符合Starks循环模型的基础上推导了噻吩氧化脱硫的反应历程.反应历程主要包括氧化活性组分从水相向有机相的转移和有机相中的离子反应两个基本阶段,通过理论计算得到了季铵盐阳离子的萃取平衡常数、阴离子的亲核性以及决定阴阳离子相互作用能的离子有效半径,筛选出了与实验结果一致的具有良好的相转移催化效果的四丁基溴化铵,脱硫率最高可达到86.36%;动力学研究结果表明,以四丁基溴化铵作为相转移催化剂(PTC),H2O2/HCOOH氧化噻吩脱硫为一级反应.

As the oxidative desulfurization by phase transfer catalysis tallies with the principle of Starks, the cycling model of oxidative desulfurization of thiophene by phase transfer catalysis was developed. The essencial processe was the transportation of active component from water phase to organic phase. The extraction constant of Q ^＋ , nucleophilicity of X^-, and r（ Q^ ＋ ） were calculated to investigate the process of oxidative desulfurization of thiophene. When thiophene was oxidized by peroxyformic acid with TBAB as the phase transfer catalyst, the desulfurization rate was up to 86.36%. From the kinetics study, it was shown that the reaction was first-order reaction.