利用微型可视毛细管反应器研究亚临界水中氯甲苯/四氯乙烯等疏水性有机物溶解度

Water near its critical point (374 C, 22.1MPa) is attracting increased attention as a medium for organic chemistry. Using sub-critical instead of organic solvents in chemical processes offers environmental advantages and may lead to pollution prevention. For using sub-critical or supercritical water (SCW) instead of organic solvents in chemical processes, the first step is to know the phase behavior, especially the fundamental reliable solubility date of hydrophobic organic compounds in hot-compressed water is essential. Many different methods were used to measure the solubility of hydrophobic organic compounds in hot-compressed water at elevated temperature and pressures, like analytical methods, synthetic methods, expressions like 'static' or 'dynamic' are used in connection with many different methods. However, almost all of the previous studies were performed in large scale stainless-steel reactors, which shown some unfavorable aspects. In the static method, withdrawing a sample from an autoclave causes a considerable pressure drop, which disturbs the phase equilibrium significantly. On the other hand, in the dynamic method, although have the advantage that sampling does not disturb the equilibrium, but the major uncertainty is the possible lack of attainment of equilibrium before sampling. In addition, these two methods require subsequent analyses. A rapid and simple method by using an optically transparent fused silica capillary reactor (FSCR) instead of the conventional stainless-steel reactors, in combination with a microscope record system for visual observation the phase behavior and identify the temperature of total dissolution, and also a Raman spectroscopic system for monitoring the dissolution progress in stiu, without sampling and subsequent analyses, to direct measurement the solubility of hydrophobic organic compounds in hot-compressed water was constructed, using this new FSCR-based method for studying the solubility of Chlorotoluene, tetrachloroethylene in subcritical water, and using Chrastil, and Unifac equation for the correlation of the experimental data. FSCR-based method is visually-accessible, low in energy and materials consumptions, expeditiousness, without sampling and subsequent analysis, and could be directly coupled with a Raman spectroscopic system for monitoring the dissolution progress in stiu. This visualization FSCR-based method has a great potential for the solubility determinations of other organic or inorganic materials under elevated pressure-temperature conditions.

亚临界水中的有机化学反应与分离过程已成为绿色化学过程研究中的热点之一。但由于高温高压实验条件的苛刻性，传统用于亚临界水中疏水性有机化合物溶解度测定的静态法取样过程容易破坏相平衡、动态法则难于保证体系已达到相平衡，致使亚临界水中疏水性有机化合物溶解度基础数据十分缺乏。申请者拟利用研发的耐高温高压微型可视石英毛细管反应器替代传统不锈钢材质高压反应器，研究氯甲苯、四氯乙烯等疏水性典型有机化合物在亚临界水中的溶解度，结合显微放大观测精确捕捉上述化合物在亚临界水体系中油-水界面的变化，及拉曼光谱原位在线检测溶液体系的混合均匀度，获得其溶解度数据，利用实验数据与模型关联建立起P-T-X模型，同时通过拉曼光谱原位在线分析有机物及水分子拉曼特征峰的峰面积、峰强度及频移的变化，探索疏水性有机物在亚临界水中随温度、压力等变化的溶解机理，为超亚临界水氧化技术工业化应用设计等过程提供基础数据。

亚临界水中的有机化学反应与分离过程已成为绿色化学过程研究中的热点之一。但由于高温高压实验条件的苛刻性，传统用于亚临界水中疏水性有机化合物溶解度测定的静态法取样过程容易破坏相平衡、动态法则难于保证体系已达到相平衡，致使亚临界水中疏水性有机化合物溶解度基础数据十分缺乏。本项目利用原创研发的耐高温高压微型可视石英毛细管反应器替代传统不锈钢材质高压反应器，研究了氯甲苯、邻二氯苯等疏水性典型有机化合物在亚临界水中的溶解度，结合显微放大观测精确捕捉上述化合物在亚临界水体系中油-水界面的变化，及拉曼光谱原位在线检测溶液体系的混合均匀度，获得其溶解度数据，利用实验数据与模型关联建立起P-T-X 模型，同时通过拉曼光谱原位在线分析有机物及水分子拉曼特征峰的峰面积、峰强度及频移的变化，探索疏水性有机物在亚临界水中随温度、压力等变化的溶解机理，为超亚临界水氧化技术工业化应用设计等过程提供基础数据。