The phenols recovery process is a significant part of treating coal chemical wastewater with highly concentrated phenols and ammonia. Solvent extraction is an important unit for phenol recovery section. The accurate measurement of liquid–liquid equilibrium (LLE) data is essential for realizing partitioning. In this paper, the LLE data for the ternary system water + 2-, 3-, 4-methylphenol +3,3-dimethyl-2-butanone (also known as methyl tert-butyl ketone, MTBK) were studied at the temperatures of 333.2 K and 353.2 K under 101.3 kPa. The extraction performance of MTBK was estimated by partition coefficients and separation factors. The extraction efficiencies of MTBK were compared with those of MIBK, mesityl oxide, and those results of MTBK at five different temperatures from 298.2 K to 353.2 K were also contrasted with each other. In addition, the nonrandom two-liquid (NRTL) and universal quasi chemical (UNIQUAC) models were applied to fit the measured LLE data. The results indicate that the calculated data based on the NRTL and UNIQUAC equations are good as reported by the experimental data, and the root-mean-square error (RMSE) values are lower than 2.50%. The obtained binary interaction parameters in this study can be used in the calculation of the LLE about the ternary system (water + 2-, 3-, 4-methylphenol + MTBK) as well as for the design and optimization of industrial process to remove methylphenols from effluents.

中文翻译：

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用3,3-二甲基-2-丁酮在333.2 K和353.2 K上从水溶液中萃取甲基酚的相平衡

苯酚的回收过程是用高浓度苯酚和氨处理煤化工废水的重要组成部分。溶剂萃取是苯酚回收段的重要单元。准确测量液-液平衡（LLE）数据对于实现分区至关重要。本文针对三元系统水+ 2-，3-，4-甲基苯酚+ 3,3-二甲基-2-丁酮（也称为甲基叔丁基）的LLE数据-丁基酮（MTBK）在101.3 kPa下于333.2 K和353.2 K的温度下进行了研究。MTBK的提取性能由分配系数和分离因子估算。将MTBK的提取效率与MIBK，异丁烯三氧化物的提取效率进行了比较，并将MTBK在298.2 K至353.2 K的五个不同温度下的提取效率进行了对比。此外，还应用了非随机二液（NRTL）模型和通用拟化学（UNIQUAC）模型来拟合测得的LLE数据。结果表明，根据NRTL和UNIQUAC方程计算的数据良好，实验数据表明，均方根误差（RMSE）值低于2.50％。