Abstract The solubilities of water in various hydrocarbons are usually needed to assess the water content in oil products. Because the solubilities of water in hydrocarbons are very small, which usually leads to large deviations in experiments, and because we have trouble carrying out experiments on bulk hydrocarbons, it is necessary to develop a more convenient molecular simulation approach to predict the solubility. In this paper, COSMO-RS, a statistical thermodynamic method based on quantum chemistry, has been employed to obtain the solubilities of water in n -alkanes, alkylcyclohexanes, alkylbenzenes and 1-alkenes by calculating the difference of the thermodynamic properties during the dissolution process. The predictions of COSMO-RS were compared with the experimental data, as well as those of API correlations and the Tsonopoulos correlation. The results indicate that COSMO-RS can better predict the trends of the solubility with high accuracy, where the deviations are within ± 29.41%. The characteristics of the solubilities of water in various hydrocarbons are interpreted systemically, especially for the influence of carbon number, CN . It particularly focuses on the non-monotonicity of the solubility curves of water in n -alkanes with the increase of CN . In addition, the effect of temperature on the characteristic of solubility is simultaneously investigated. Graphic Abstract

中文翻译：

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COSMO-RS预测​​水在烃中的溶解度及溶解度特征解释

摘要 通常需要水在各种烃中的溶解度来评估油品中的水含量。由于水在碳氢化合物中的溶解度很小，通常会导致实验偏差很大，而且由于我们很难对大量碳氢化合物进行实验，因此有必要开发一种更方便的分子模拟方法来预测溶解度。本文采用基于量子化学的统计热力学方法COSMO-RS，通过计算溶解过程中热力学性质的差异，得到水在正烷烃、烷基环己烷、烷基苯和1-烯烃中的溶解度。 . COSMO-RS 的预测与实验数据以及 API 相关性和 Tsonopoulos 相关性的预测进行了比较。结果表明，COSMO-RS可以更好地预测溶解度的趋势，准确度高，偏差在±29.41%以内。系统地解释了水在各种烃中的溶解度特征，特别是碳数 CN 的影响。它特别关注了水在正构烷烃中的溶解度曲线随着 CN 的增加的非单调性。此外，同时研究了温度对溶解度特性的影响。图形摘要 它特别关注了水在正构烷烃中的溶解度曲线随着 CN 的增加的非单调性。此外，同时研究了温度对溶解度特性的影响。图形摘要 它特别关注了水在正构烷烃中的溶解度曲线随着 CN 的增加的非单调性。此外，同时研究了温度对溶解度特性的影响。图形摘要