Bioethanol Production from Ball-Milled and Regenerated Rice Husk

Abstract:

This research focused on the bioethanol production from rice husk via enzymatic hydrolysis and fermentation of glucose product. Rice husks were ball-milled, alkali pretreated with 2 %(w/v) NaOH for 3 hours and regenerated by N-methylmorpholine N-oxide (NMMO)/H₂O solution into Cellulose II structure. These processes were aimed to enhance the surface purity area and accessibility of enzyme, respectively. Rice husks were hydrolyzed with cellulase from Trichoderma reesei ATCC 26921 at various concentrations ranging from 10 to 40 FPU/g of rice husk. The maximum yields of glucose from alkali pretreated rice husk, ball-milled rice husk of sieve size 45-75 μm and regenerated rice husk were 7.13, 9.52 and 10.36 mg/mL, respectively. This was conducted at the enzyme concentration of 20 FPU/g of rice husk for 48 hours. The glucose product was fermented by using Saccharomyces cerevisiae Safale US-05 at various concentrations ranging from 10 to 70 %(v/v). The maximum yields of ethanol products at 50 %(v/v) of yeast and 48 hours of fermentation from the alkali pretreated rice husk, ball-milled rice husk of sieve size 45-75 μm and regenerated rice husk were 44.36%, 68.79% and 89.11% of glucose respectively. The greater yield may be arise from an increase in surface area and the swollen cellulose structure of rice husk.

• Periodical: Key Engineering Materials (Volume 757)
• Pages: 161-165
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.757.161
• Online since: October 2017
• Authors: Sirisart Ouajai*, Riangploy Wanichayachart, Thapanee Suksomprasong, Atchara Pisitwinyoo
• Keywords: Bio-Ethanol, Enzymatic Hydrolysis, Regenerated Cellulose, Rice Husk

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