GOALI: Molecular Dynamics Simulations of Membrane Assisted Phase Equilibrium in Dilute Solutions

Murad, Sohail - U of Illinois - chicago - miller， Jeffrey - BP研究中心，Naperville， ilgoal：稀溶液中膜辅助相平衡的分子动力学模拟PI建议开发一种直接模拟方法来研究稀溶液的相平衡。该方法是基于使用膜来帮助达到两个或多个相之间的平衡。直接模拟方法，虽然概念上最简单的研究相平衡的方法通常很难实现，因为它们需要：(i)长时间的模拟来解释缓慢的扩散通过界面；（ii）大型系统，以考虑界面的厚度，并具有足够大的区域来代表体相；和（iii）不适用于两相密度接近的情况，因为很难保持两相分离。使用膜辅助方法研究气体在液体中的溶解度的初步工作表明，其他直接模拟方法的许多问题在这种直接模拟方法中明显较少。所提出的研究的总体目标是进一步发展这种方法来研究更广泛的相平衡问题，特别是那些直接的工业利益。它们将包括各种气体在溶剂中的溶解度。气体在溶剂中的选择性溶解度被认为是分离气体的一种有效技术，否则难以分离（如乙烯/乙烷）。此外，诸如O2、N2、C2H4、C2H6等气体在醇、醚和碳氢化合物等溶剂中的溶解度本身在化学和石油工业中也引起了相当大的兴趣。除了具有直接的工业意义外，这些性质对不同物种（例如极性/非极性）之间的交叉相互作用非常敏感，而这些相互作用在分子和宏观水平上都没有得到很好的理解。PI还将调查其他相关问题，例如溶质在竞争溶剂中的分配，这对预防和减少污染很重要。这项研究是与BP美国公司、陶氏化学公司和亨斯迈公司的合作项目，这些公司表示愿意投入大量工业资源，以表示他们对该项目的成功感兴趣。PI的意图是在该GOALI提案下证明这些方法对重要工业项目的稳健性，并随后与这些公司密切合作，使他们能够将其用于更直接和直接的工业利益的其他问题和系统。PI还将开发用户友好的计算机代码，这些代码将提供给工业伙伴用于发展目的。最后，产业合作将允许研究生与产业科学家互动，并为他们的研究生教育体验增加一个重要的维度。

Murad, Sohail - U of Illinois - ChicagoMiller, Jeffrey - BP Research Center, Naperville, ILGOALI: Molecular Dynamics Simulations of Membrane Assisted Phase Equilibrium in Dilute SolutionsThe PI's propose to develop a direct simulation method to investigate the phase equilibrium of dilute solutions. The method is based on using a membrane to assist in attaining equilibrium between two or more phases. Direct simulation methods, although conceptually the simplest methods for studying phase equilibrium are usually difficult to implement because they require: (i) long simulation times to account for slow diffusion through the interface; (ii) large systems to account for the thickness of the interface and to have sufficiently large regions to represent the bulk phases; and (iii) are not suitable when the densities of the two phases are close to each other, since it becomes difficult to maintain two separate phases. Preliminary work using the membrane-assisted method to study the solubility of gases in liquids, has shown that many of the problems with other direct simulation methods are significantly less problematic with such direct simulation methods. The overall goal of the proposed research is to further develop this method to study a wider range of phase equilibrium problems, especially those of direct industrial interest. They will include solubility of a wide range of gases in solvents. Selective solubility of gases in solvents has been suggested as an efficient technique for separating gases, which are otherwise difficult to separate (e.g. ethylene/ethane). In addition, the solubility of gases such as O2, N2, C2H4, C2H6, etc., in solvents such as alcohols, ethers, and hydrocarbons are of considerable interest by themselves in the chemical and petroleum industries. Apart from being of direct industrial interest, these properties are very sensitive to cross interactions between different species (e.g. polar/nonpolar) which are not well understood at both the molecular and macroscopic level. The PI's will also investigate other related problems such as the partitioning of solutes in competing solvents, which are important in pollution prevention and abatement. This research is a collaborative project with BP America, Dow Chemical Company, and Huntsman Corporation, who have expressed a willingness to commit considerable industrial resources as an expression of their interest in the success of this project. It is the PI's intention to demonstrate the robustness of these methods for important industrial projects under this GOALI proposal, and subsequently work closely with these companies to enable them to use it for additional problems and systems of more immediate and direct industrial interest. The PI's will also develop user-friendly computer codes that will be made available to the industrial partners for developmental purposes. Finally, the industrial collaboration will allow graduate students to interact with industrial scientists, and add an important dimension to their graduate education experience.