| The applications, production technology, futureprospect of Isooctyl mercapto-acetate were summarized in this paper. The problem of solvent recovery during the manufacture of Isooctyl alcohol, that is, separating the mixture system of Mercaptoa-cetic Acid and water, was analyzed. The performance and applications of Mercaptoa-cetic Acid and water were introduced. What’s more, the difficulty in separating and purifying the mixture system of Mercaptoacetic Acid and water were analyzed and the recent methods of separating Mercaptoacetic Acid from its solution were reviewed in the paper. Then, a method of liquid-liquid extraction was also carried out to separate Mercaptoacetic Acid from its solution.According to the general principle of extractants selections, some new researches and experiments were carried out, it turned out that Isooctyl alcohol could be chosen as the right extracting to separate Mercaptoacetic Acid-water mixed solution. Esteri-fication was used between Isooctyl alcohol and Mercaptoacetic Acid, and then isooc-tyl thioglycolate and Isooctyl alcohol were separated. Comprehensive utilization of renewable resources was achieved.Further, the extraction capacity of isopropanol as the extraction agent was ana-lyzed by single factor analysis method. Different influencing factors on the liq-uid-liquid equilibrium such as stirring time, stirring velocity and setting time were studied in detail on the basic of which the liquid-liquid data were tested. The interac-tive parameters of NRTL and UNIQUAC equation were correlated, the basic LLE da-ta were simulated. The results showed that NRTLequation was more suitable.On the basic of optimal condition, experiments of cross-flow extraction were conducted, considering the influencing factors of solvent ratio and extraction progres-sion. The results showed that the Quality content of 1 Mercaptoacetic Acid could be less than 0.50% by three extraction progressions at the ratio SF=1:1.Experiments of countercurrent extraction were Simulated with NRTL consider-ing the influencing factors of raw ratio. The results showed that in the condition of 4 theoretical series, the Quality content of Mercaptoacetic Acid was 0.42% at the ratio S:F=1:1.Compared with countercurrent extraction, the results of cross-flow extraction was better.Finally, the Quality content of Mercaptoacetic Acid In the caffeinate phase could be less than 0.50% after cross-flow extraction, isooctyl thioglycolate products was obtained by Esterification in the extraction phase. Meanwhile, isooctyl thioglycolate and Isooctyl alcohol could be recycled through multi-distillation according to litera-tures.A whole liquid-liquid process of separating Mercaptoacetic Acid and water sys-tem has been provided in this paper. Both cross-flow extraction and countercurrent extraction were carried out to separate the mixture, whose process is simple, energy consumption is low and yield is high. The study would provide fundamental refer-ences for further industrialization process of separation of Mercaptoacetic Acid and water.
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