三辛胺络合萃取分离一氯乙酸和二氯乙酸  

Separation of monochloroacetic acid and dichloroacetic acid with trioctylamine based on chemical complexation

作　　者：陈颍颍[1] 沈剑[1] 何潮洪[1] 

机构地区：[1]浙江大学化学工程与生物工程学系,化学工程联合国家重点实验室,浙江杭州310027

出　　处：《化工学报》2013年第2期609-615,共7页CIESC Journal

基　　金：浙江省重点科技创新团队项目(2009R50002,2010R50017)~~

摘　　要：以三辛胺(TOA)工业品为萃取剂、正己烷为稀释剂,研究了一氯乙酸和二氯乙酸(质量比为322∶1)水溶液的萃取分离特性,考察了温度和初始萃取剂浓度对萃取平衡的影响,建立了TOA萃取一氯乙酸和二氯乙酸的数学模型。结果表明,两酸分配系数随温度升高而增大,但影响有限;随萃取剂初始浓度的增大,一氯乙酸分配系数随之增大,二氯乙酸分配系数先升后降。基于TOA的表观碱度,建立了二氯乙酸单溶质模型,解释了其分配系数随萃取剂浓度增大先升后降的特殊规律;在此基础上,考虑协同萃取的影响,建立了双溶质萃取模型。上述研究为一氯乙酸工业品的进一步提纯分离提供了指导。The extraction behavior of monochloroacetic acid and dichloroacetic acid with a mass ratio of 322 ： 1 was investigated with trioctylamine （TOA） as the extractant and n-hexane as the diluent. The effects of temperature and initial concentrations of TOA on distribution coefficient were studied, and the mathematical models were proposed to describe the extraction equilibrium. The experimental results show that the effect of temperature on the distribution coefficient is small. The distribution coefficient for monochloroacetic acid increases with the concentration of TOA, while that of dichloroacetic acid increases first and then decreases as the concentration of TOA increases. Based on the apparent basicity of TOA in extraction, the mathematical model in single dichloroacetic acid system is proposed to describe the relationship between dichloroacetic acid and TOA. Further, the mathematical models in mix acid system are proposed based on the synergistic extraction. Therefore, it will be of great significance in industry.

关 键 词：络合萃取 三辛胺 一氯乙酸 二氯乙酸 

分 类 号：TQ028.8[化学工程]