加盐萃取精馏分离邻二甲苯-苯乙烯的研究

Study on separating o-xylene-styrene by extractive distillation with salt

测定了不同萃取剂和盐对邻二甲苯-苯乙烯近沸程物系相对挥发度的影响,研究了盐质量浓度、萃取剂加入速率和回流比对加盐萃取精馏的影响,并建立了反映塔顶馏出液中邻二甲苯质量分数与各因素关系的回归模型。研究结果表明,环丁砜(DMSO)-水(质量分数3%)-硫氰酸钾(KCNS,0.03 g/mL)可作为加盐萃取精馏分离邻二甲苯和苯乙烯体系的最佳加盐萃取剂。

The influence of different extractants and salts on the relative volatility of o-xylene-styrene is determined. The effects of different concentration of salt, adding rate of extractant and reflux ratio on the extractive distillation with salt are studied, and the regression model reflecting the relationship between the mass fraction of o-xylene in top of distillation and the above factors is established. The investigation shows that sulfolane （DMSO）-water （mass fraction 3 %）-KCNS （0.03 g/mL） is the most suitable extractant with salt for separating o-xylene-styrene by extractive distillation with salt.