Continuous Ethanol Fermentation and Recovery Using an Improved Zeolite Membrane Bioreactor

主要研究者：Nielsen，大卫机构：亚利桑那州州立大学提案号：1067684标题：使用改进的沸石膜生物反应器的连续乙醇发酵和回收本研究旨在开发一种实验室规模的生物工艺，该工艺将发酵与沸石膜渗透蒸发相结合，用于高速率，高纯度和连续生产生物燃料乙醇。为了支持这一目标，研究由三个主要目标组成：1）具有提高的乙醇选择透过性和通量的改进的无铝疏水沸石膜的合成和开发，2）在膜表面发生的非理想物理/生物现象的表征，和3）设计，开发，和表征新的生物过程，包括沸石膜渗透蒸发作为一种经济的手段，在原位产品回收。智力优点：第一个主要目标集中于在化学惰性多孔氧化锆载体上合成高质量的无铝硅沸石膜。这些新的膜，这将在磁盘和管状几何形状制造，预计将表现出更高的通量和乙醇/水的选择性比现有的聚合物和沸石膜。第二个重要的目的是提供基本的洞察力的非理想的，物理和/或生物的相互作用发生在沸石表面上的机械性质，以及它们对膜的性能和分离性能的影响所产生的效果。这些研究将有助于发展一个机械的理解生物污垢（蛋白质和全细胞）作为相关的工艺条件和生物催化剂基因型的功能。最后的目的是设计，开发和表征一个可扩展的和集成的生物过程，用于连续生产和回收乙醇从酵母发酵使用沸石膜渗透蒸发。为了支持持续和高水平的性能，操作政策和减污策略，包括原位再生膜反冲洗，将制定和优化。更广泛的影响：这项研究将使分离科学和生物工艺设计的发展，支持可持续生物燃料的发展。无铝硅沸石膜制备的概念最终可以转化为其他沸石膜的合成，以实现更大的材料相容性和更高的性能，用于其他分离应用。新合成的管状沸石膜及其合成方案可以发现用于分离具有工业重要性的气体和液体混合物的其它应用，例如烃/氢和其它醇/水混合物的炼厂气。通过沸石膜渗透蒸发能够选择性分离抑制性产物的生物过程的开发可以在生产额外的生物化学品和新兴的下一代生物燃料方面具有更广泛的应用。在沸石表面的物理/生物相互作用的表征可能是有价值的，用于评估沸石材料在从生物能源生产到生物医学工程等领域的未来前景。通过这项研究征聘的人员和两用设备资源将使生物实验室模块的开发成为可能，以丰富本科生的教育经验。

PI: Nielsen, David Institution: Arizona State University Proposal Number: 1067684Title: Continuous Ethanol Fermentation and Recovery using an ImprovedZeolite Membrane BioreactorThis research aims to develop a lab-scale bioprocess which integrates fermentation with zeolite membrane pervaporation for the high-rate, high-purity, and continuous production of biofuel ethanol. To support this objective, the research is composed of three principal aims: 1) the synthesis and development of improved, aluminum-free hydrophobic zeolite membranes with both elevated ethanol permselectivity and flux, 2) characterization of non-ideal physical/biological phenomena occurring at the membrane surface, and 3) the design, development, and characterization of novel bioprocesses incorporating zeolite membrane pervaporation as a means of economical, in situ product recovery.Intellectual Merit: The first principal aim focuses on the synthesis of high quality, aluminum-free silicalite membranes on chemically inert porous zirconia supports. These new membranes, which will be fabricated in both disk and tubular geometries, are expected to demonstrate much higher fluxes and ethanol/water selectivity than existing polymer and zeolite membranes. The second important aim is to provide fundamental insights into the mechanistic nature of non-ideal, physical and/or biological interactions occurring upon zeolite surfaces, as well as their resultant effect on membrane properties and impact on separation performance. These studies will help to develop a mechanistic understanding of biofouling (by both proteins and whole cells) as a function of relevant process conditions and biocatalyst genotype. The final aim is to design, develop, and characterize a scalable and integrated bioprocess for the continuous production and recovery of ethanol from yeast fermentations using zeolite membrane pervaporation. To support sustained and high-level performance, operating policies and fouling reduction strategies, to include in situ regeneration by membrane backflushing, will be developed and optimized.Broader Impact: This study will enable developments in separation science and bioprocess design, supporting the development of sustainable biofuels. The concept of aluminum-free, silicalite membrane preparation can ultimately be translated to the synthesis of other zeolite membranes to enable greater material compatibility and higher performance for other separation applications. Newly synthesized tubular zeolite membranes and their synthesis protocols could find other applications for separation of gas and liquid mixtures of industrial importance, such as refinery gas of hydrocarbon/hydrogen and other alcohol/water mixtures. The development of a bioprocess enabling the selective separation of inhibitory products by zeolite membrane pervaporation could have broader applications for the production of additional biochemicals and emerging, next generation biofuels. The characterization of physical/biological interactions at zeolite surfaces could be valuable for assessing the future prospects of zeolite materials in fields ranging from bioenergy production to biomedical engineering. The recruited personnel and dual-use equipment resources made possible through this study will enable the development of biologically-based laboratory modules to enrich the educational experiences of undergraduates.