为了得到渗透物小分子在聚合物膜内的溶解和扩散性质,进而研究膜分离机理并指导膜材料选择,本文选用反相气相色谱法研究溶剂与聚合物材料之间的相互作用.在80~100℃温度范围内,采用气相色谱法测定噻吩、2-甲基噻吩、2,5-二甲基噻吩、丁硫醚、丁硫醇五种典型的形态硫及正庚烷在硅橡胶中的无限稀释活度系数和扩散系数,对比膜分离性能的实验数据,分析了不同分子结构及其特点对于聚合物/溶剂体系溶解扩散性能的影响.结果表明,随着温度升高,有机硫的无限稀释活度系数和无限扩散系数都增大.在同一温度下,无限稀释活度系数顺序是:噻吩〈2-甲基噻吩〈2,5-二甲基噻吩〈正庚烷〈正丁硫醚〈正丁硫醇,无限稀释扩散系数顺序为:噻吩〉2-甲基噻吩〉2,5-二甲基噻吩〉正丁硫醇〉正庚烷〉正丁硫醚.该成果为膜法汽油脱硫深入研究和工业应用奠定了基础.
In order to obtain the properties of the solution and the diffusion for the penetration small molecule in the membrane,and also to study the mechanics of membrane separation process for directing the choice of membrane materials,inverse gas chromatography method is confirmed to study the lation of the solvent and polymer systems.The infinite dilute activity and diffusion coefficients of thiophene〉2-methyl thiophene,2,5-dimethyl thiophene,n-butyl mercaptan,n-butyl sulfide and heptane in cross-linked PDMS were obtained in the temperature range of 80-100 ℃ by inverse gas chromatography.The results showed that the order of infinite dilute activity coefficients was: thiophene 〉2-methylthiophene 〉2,5-dimethylthiop〉heneheptane〉 n-butyl sulphide〉 n-butyl mercaptan,and the order of infinite dilute diffusion coefficients was: thiophene 〉2-methylthiophene 〉2,5-dimethylthiopheneheptane n-butyl mercaptan n-butyl sulphide.This work makes a foundational contribution to further investigation on gasoline desulfurization and practical industry application.