U.S.-Egypt Cooperative Research: Functionalized Membranes for Acid Catalysis

0612267里奇描述： 该奖项旨在支持亚拉巴马塔斯卡卢萨市亚拉巴马大学化学工程系Stephen里奇博士和埃及开罗国家研究中心（NRC）Elham El Zanati博士的合作研究。 他们计划对酸催化功能化膜进行研究。该研究旨在解决一类基于功能化膜的新型固相酸催化剂的开发和基本理解。通过磺化膜孔中的聚苯乙烯接枝物将酸基团添加到微滤膜。通过苯乙烯的原位聚合将聚合物接枝物固定在膜孔中。简单地在膜上施加低压梯度就足以实现酸位点和反应物之间的良好接触。对流的重要性（仅在膜中可能）在于它使反应物能够完全且快速地接近酸位点。 实验工作将由包括本科生和研究生在内的初级科学家进行，重点是创造参与和传播结果的机会。 知识优势：酸催化是化学加工工业中的关键工艺。 常规的酸催化在均相溶液（无机酸）中或通过与固相（例如，离子交换树脂）。前者提供了优异的反应物对催化剂的可接近性，但存在腐蚀和催化剂回收的问题。固相催化剂的使用简化了催化剂的回收，同时腐蚀较小，但由于传输受扩散支配，因此引入了阻碍可达性的新问题。这项研究将导致更好地了解接枝过程与聚合反应过程中的自由基和实验测定的操作参数。感兴趣的反应包括乙酸乙酯和异辛烷的酯化和烷基化反应。对于后一种系统，功能化膜非常适合于克服分散在二氧化硅上的Nafion所遇到的问题，其中载体的可接近性和失活导致催化剂活性降低。更广泛的影响：拟议的工作将导致一种新的酸催化剂的化学加工工业的发展。它具有替代燃料，特别是生物燃料的有益应用。当原料中含有游离脂肪酸时，酸催化酯化是生产生物柴油的重要方法。这些脂肪酸可以从常规的固相酸催化剂中排除，并且在均相溶液中容易发生副反应。催化膜将是克服这些问题的一种方法，并可能对生物柴油和其他替代燃料的大规模生产产生重大影响。这些材料还可以提供用于烷基化的现有固相酸催化剂的替代物，其具有低可及性和失活。这项工作将涉及两名美国本科生。美国私人侦探将进行互访。该项目得到了美国-埃及联合基金计划的支持，该计划向两国的科学家和工程师提供赠款，以开展这些合作活动。

0612267RitchieDescription: This award is to support a cooperative research by Dr. Stephen Ritchie, Department of Chemical Engineering, University of Alabama, Tuscaloosa, Alabama and Dr. Elham El Zanati, National Research Center (NRC), Cairo, Egypt. They plan to conduct research on Functionalized Membranes for Acid Catalysis. The research is to address the development and fundamental understanding of a new class of solid-phase acid catalysts based on functionalized membranes. Acid groups are added to a microfiltration membrane by sulfonation of polystyrene grafts in the pores of the membrane. Polymer grafts are immobilized in the membrane pores by in-situ polymerization of styrene. Simple application of a low pressure gradient across the membrane is sufficient to achieve excellent contact between acid sites and the reactants. The importance of convective flow (only possible in the membrane) is that it enables the complete and rapid accessibility of reactants to acid sites. Experimental efforts will be performed by junior scientists including undergraduate and graduate students, with an emphasis of creating opportunities for Involvement and dissemination of results. Intellectual Merit: Acid catalysis is a critical enabling process in the chemical process industry. Conventional acid catalysis is performed in homogeneous solution (mineral acids) or by contact with a solid phase (e.g., ion exchange resins). The former offers excellent reactant accessibility to the catalyst, but suffers from problems with corrosion and catalyst recovery. The use of solid phase catalysts simplifies catalyst recovery with less corrosion, but introduces the new problem of hindered accessibility because transport is dominated by diffusion. This research should lead to a better understanding of the grafting process with polymerization by free radical processes and experimental determination of operating parameters during reaction. Reactions of interest include esterification and alkylation for ethyl acetate and isooctane, respectively. For the latter system, functionalized membranes are ideally suited to overcome problems seen with Nafion dispersed on silica, where accessibility and deactivation by the support result in degradation of catalyst activity. Broader Impact: The proposed work will result in the development of a new acid catalyst for the chemical process industry. It has beneficial applications for alternative fuels, and biofuels in particular. Acid catalyzed esterification is important for the production of biodiesel when the feedstock contains free fatty acids. These fatty acids can be excluded from conventional solid phase acid catalysts, and are susceptible to side reactions in homogeneous solution. A catalytic membrane would be a way to overcome these problems, and may have a major effect on the large scale production of biodiesel and other alternative fuels. These materials may also offer an alternative to existing solid phase acid catalysts for alkylations, which suffer from low accessibility and deactivation. The work will involve two US undergraduate students. There will be exchange of visits by the US P.I. and the Egyptian collaborators to each others laboratories and this should expand relations between the scientific communities in both countries.This project is being supported under the US-Egypt Joint Fund Program, which provides grants to scientists and engineers in both countries to carry out these cooperative activities.