Abstract
The use of lignocellulosic biomass to produce biofuel will add value to land and reduce emissions of greenhouse gases by replacing petroleum products. Valuable co-products derived from fractionation of alfalfa (Medicago sativa) give the resulting fibrous fraction an economic advantage as a feedstock for ethanol production. Freshly harvested alfalfa was dewatered using centrifugation and filtration, whereby alfalfa is separated into a fiber-rich cake and a nutrient-rich juice. Alfalfa solids was pretreated with alkaline soaking (1, 4, and 7 %) at room temperature to evaluate the effects on cellulose digestibility. The production of cellulosic ethanol from alfalfa fibers were investigated by this work using separate hydrolysis and fermentation (SHF). Results show the alkali pretreatment was able to effectively increase cellulosic digestibility of alfalfa solids. A maximal glucose yield of 61 % was obtained with filtered solids with 1 % NaOH pretreatment. The filtration process resulted in a solid fraction with a higher cellulose digestibility, which leads to a higher ethanol production.
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Acknowledgement
The authors are grateful for the support of the USDA-CSREES-Evans-Allen Project, Grant No. NCX-272-5-13-130-1.
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Xiu, S., Boakye-Boaten, N.A., Shahbazi, A. (2016). Separate Hydrolysis and Fermentation of Untreated and Pretreated Alfalfa Cake to Produce Ethanol. In: Uzochukwu, G., Schimmel, K., Kabadi, V., Chang, SY., Pinder, T., Ibrahim, S. (eds) Proceedings of the 2013 National Conference on Advances in Environmental Science and Technology. Springer, Cham. https://doi.org/10.1007/978-3-319-19923-8_24
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DOI: https://doi.org/10.1007/978-3-319-19923-8_24
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-19922-1
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