Comparative Study of Bioethanol Production from Wheat Straw and Rice Straw

The study was carried out to determine the proximate and comparative analyses in the production of bioethanol from lignocellulosic biomass, rice straw and wheat straw. The proximate composition were determined in accordance with ASTM analytical methods. Ethanol production from agro waste was optimized using 2% NaOH solution to chemically pretreat milled straw. Pretreated and un-pretreated straws were subjected to hydrolysis and fermented. The hydrolysate and fermented filtrate were analyzed using UV-spectrophotometer and FTIR on complete hydrolysis, the straw hydrolysate gave a higher fermentable sugar concentration for the pretreated milled straw than un-pretreated straw. An increase in the reducing sugar amount of 36.00% and 28.85% for rice and wheat straw respectively were the result of difference and improvement due to alkaline pretreatment. Obtained fermentable sugar due to alkaline pretreatment of milled rice straw and wheat straw are 4.42g/l and 4.60 g/l respectively relative to a lower value of the un-pretreated rice straw and wheat straw of 3.25g/l and 3.57g/l respectively. Alkaline pretreatment prior to downstream processes improved the efficiency of the bioconversion of cellulose to glucose, hence it optimizes the bioconversion process by increasing the ethanol yield of room fermented rice straw from 57.65% to 61.55% and wheat straw from 61.80% to 64.02%, and also increased the yield of straws fermented in the incubator from 55.77% to 58.46% for rice and 60.16% to 62.64% for wheat. Keywords: Bioethanol, Pretreatment, Hydrolysis, Lignocellulosic biomass, Bioconversion.