CO2-Enhanced Aqueous Extraction for Benign Separation of Reaction Products

GA Tech res Corp-GIT“二氧化碳增强型水萃取用于反应产物的良性分离”分离和产品提纯对于环境友好和经济上有吸引力的化学过程至关重要。在这个项目中，将证明二氧化碳的热力学性质可以改变相界和分配系数，以提供良性和有效的反应产物分离和均质催化剂的回收。这些工艺将通过减少不良副产物的产生以及减少水和催化剂回收所需的能量来防止污染。二氧化碳与大多数有机物混溶，但实际上与水不相容；它也是有机物中的一种强大的抗溶剂。它经常以这种方式用于颗粒生产或分离结晶，但这些应用需要饱和溶液。PIS建议将其与水萃取结合使用，以提高从较稀薄的有机溶液中的回收率。本文提出的系统即使在稀溶液中也可以有效地运行。PI将显示包含水和有机物的体系，其中添加二氧化碳将导致二氧化碳仅在有机物中大量吸收。这可以实现可混溶的有机/水混合物的相分离，或者极大地改变有机/水两相体系的分配系数。因此，这使得疏水和亲水部分之间的反应成为可能，反应后易于分离和纯化。此外，它还提供了催化剂的良性循环，这些催化剂可能是昂贵的和/或有毒的。这项研究将展示新型溶剂系统的优势，并将开发实施这些系统所需的热力学数据和相平衡关联。广泛影响：提出这项工作的小组是一个多元化的联合化学工程-化学团队，拥有广泛的工业合作伙伴。这种形式对多学科教育和技术转让都特别有利。其结果将是对优秀的化学/环境科学家和工程师的教育，以及改善当前和未来基于溶剂的工艺造成的严重污染。

Eckert, Charles A., et al.GA Tech Res Corp - GIT"CO2 Enhanced Aqueous Extraction for Benign Separation of Reaction Products"Separation and product purification are crucial for environmentally benign and economically attractive chemical processes. In this project, it will be shown that the thermodynamic properties of CO2 can modify phase boundaries and distribution coefficients to provide benign and efficient separation of reaction products and recycle of homogeneous catalysts. These processes will prevent pollution both by making fewer undesirable side products as well as by reducing water and energy needed for catalyst recycle.CO2 is miscible with most organics but virtually immiscible with water; also it is a powerfulantisolvent in the organics. It has often been used in this manner for particle production or forfractional crystallization, but these applications require a saturated solution. The PIs propose to use it in conjunction with aqueous extraction to enhance recovery from more dilute organic solutions. The system proposed here can operate effectively even in dilute solutions.The PIs will show that systems containing water plus an organic where the addition of CO2 will result in significant absorption of CO2 into the organic only. This can achieve phase separation of a miscible organic/water mixture, or change drastically distribution coefficients in a two-phase organic/water system. As such this makes possible reactions between hydrophobic and hydrophilic moieties, with facile separation and purification after reaction. In addition it provide for benign recycle of catalysts which may be expensive and/or toxic.This research will show the advantages of novel solvent systems and will develop the thermodynamic data and phase equilibrium correlations needed to implement these systems.Broader Impact: The group proposing this work is a diverse joint Chemical Engineering -Chemistry team with extensive industrial partners. This format is especially advantageous forboth multidisciplinary education and for technology transfer. The results will be both theeducation of superior chemical/environmental scientists and engineers, as well as amelioration ofsubstantial pollution by current and future solvent-based processes.