环丁砜-N-甲基吡咯烷酮芳烃抽提溶剂的研究

Initial Studies on the Extraction of Aromatics with Sulfolane and its Combination with N-Methyl-Pyrrolidone(NMP)

采用浊点法测定了苯-正庚烷-(环丁砜+N-甲基毗咯烷酮)四元体系在30±0.1℃下的液液分层曲线,结合体系的物性(如折光指数或比重),又测定了上述体系的结线数据。为了评价混合溶剂的萃取性能,用上述相同的方法铡定了苯-正庚烷-环丁砜三元体系在30±0.1℃下的液液分层曲线和结线数据。由试验数据计算而得的溶解度和选择性系数等数据,可以清楚看出,环丁砜与 N-甲基吡咯烷酮组合成为劳烃抽提溶剂,减小了二相共存区,N-甲基吡咯烷酮可能被称之为“潜溶剂”。并研究了温度变化的影响。

Liquid-liquid binodal curves have been determined for the quaternary sys-tems benzene-n-heptane-(sulfolane plus N-methyl-pyrrolidone)(with different ra-tio by vol.)at 30±0.1℃ by the turbidity point titration method.Conjugate linesfor the above mentioned systems have also been determined in conjunction withthe physical properties,such as refractive index and specific gravity.With a view to evaluating the extractive properties of the combinedsolvents,binodal curves and conjugate lines have also been determined for thetertiary system benzene-n-heptane-sulfolane at 30±0.1℃ by the same way as forthe above-mentioned quaternary systems.Based on the solubility(S)and selectivity(β)calculated from the experimentaldata,it can be clearly seen that NMP may be considered as a cosolvent decreas-ing the size of the two phase envelope.In addition,the effect of temperaturechanges was studied.