High-Performance, Low-Cost Pervaporation Modules for Ethanol Extraction

72215-Demand for ethanol as a transportation fuel has been growing substantially and this growth is anticipated to continue. Most ethanol is produced via fermentation of sugars derived from corn and is comparatively expensive, in large part due to the high capital and energy costs for fermentation and for separating the product from the fermentation broths. Technologies to improve the efficiency of ethanol separation and to better integrate the fermentation and downstream separation processes are needed to lower the cost of fuel ethanol. This project will develop novel low-cost inorganic pervaporation membrane modules that have superior separation properties for extracting ethanol from fermentation broths, particularly for biomass-derived ethanol, significantly improving the energy efficiency and related costs for each of these operations. In Phase I, the feasibility of fabricating high-performance inorganic ethanol-separation membranes on prototype supports was demonstrated. The ethanol fluxes obtained with the innovative membrane devices were outstanding as compared to existing technology. In Phase II, fabrication methods for the novel inorganic membranes will be improved and the membranes will be scaled-up to larger areas. The ethanol separation properties of the scaled-up membranes will be demonstrated in extended tests, primarily through use of live fermentation broths as feed streams. The data acquired will be used to evaluate the projected economics of several coupled pervaporation-fermentation process schemes for ethanol production. Commercial Applications and Other Benefits as described by awardee: The technology should provide an important reduction in initial capital costs, capital recovery costs, and operating costs for fuel ethanol plants. This would be an important step in reducing the costs of starch-derived and biomass-derived ethanol, making it more cost-competitive with petroleum-derived fuels. The technology also should be applicable for other fermentations in the production chemical and pharmaceutical products.