摘要
用绿色溶剂碳酸二甲酯(DMC)萃取苯酚废水消除二次污染问题。研究了20℃下的三元体系DMC-水-苯酚和四元体系DMC-正己烷-水-苯酚的液液萃取相平衡,用UNIFAC模型计算了DMC在液相中的活度系数。结果表明,苯酚在有机相和水相间的分配系数为常数,不随着水相苯酚浓度变化。当有机相初始DMC浓度不同时,分配系数不同,萃取溶剂相中初始DMC体积浓度由50%增加到80%时苯酚的分配系数由10增加到19左右。定义了新UNIFAC基团OCOO,用最小二乘法回归得到了OCOO与CH2、H2O、ACH、ACOH等基团间的相互作用参数。对三元和四元体系的液液相平衡进行了预测,结果表明得到的相互作用参数可以较好地对液液相平衡进行推算。
Dimethyl carbonate（DMC） was selected as green extractant to prevent the secondary pollution existing in current liquid-liquid extraction process using extractant with toxicity to recover phenol from water. Liquid-liquid equilibrium of ternary system water-phenol-DMC and quaternary system water-phenol-DMC-hexane was measured at 20℃. The activity coefficient of DMC in the liquid phase was calculated by using model of UNIFAC. Experiments show that the distribution coefficient of phenol in organic and aqueous phases is a constant and doesn＇t change with the phenol concentration in the aqueous phase, but the value of the constant is different for the extracting solvent with different initial volumetric concentration of DMC. The distribution coefficient of phenol is increased from 10 to 19 when the initial volumetric concentration of DMC in the extracting solvent is changed from 50% to 80%. A new UNIFAC group OCOO was defined in this paper and its interaction parameters with CH2, H2O, ACH, ACOH were regressed from the experimental data. Liquid-liquid equilibrium of quaternary system is successfully predicted by using UNIFAC method and these regressed Darameters.
出处
《高校化学工程学报》
EI
CAS
CSCD
北大核心
2005年第5期686-690,共5页
Journal of Chemical Engineering of Chinese Universities
基金
国家自然科学基金资助项目(29836130)。
