<![CDATA[The quantity of waste generated by agriculture is increasing and biomass based renewable energy can be developed based on this waste. Rice husk is one such lignocellulosic biomass that has potential as raw material for the production of bioethanol, but the use is still small because of the complex structure of lignocellulosic biomass, especially the existence of lignin, which is a barrier to cellulose during hydrolysis and fermentation. This study is designed to assess the impact of pretreatment with Choline Chloride – Urea based Deep Eutectic Solvent (DES) on the lignocellulosic properties of rice husks (RH) and its bioethanol production. The research steps comprise of raw material preparation, synthesis of DES, pretreatment process, analysis of the lignocellulosic fractions, enzymatic saccharification process and bioethanol fermentation process. Results from the treatments indicate that the DES treatment changes the lignocellulosic composition by reducing lignin content from 21.77% to 12.87%, hemicellulose content from 18.17% to 11.20% and increasing cellulose content from 35.13% to 52.27%. With the enzymatic saccharification, the glucose concentration obtained was 49.99 g/L and the saccharification efficiency was 86.08%. Later, the maximum concentration of ethanol as 21.40 g/L was obtained on the fifth day with 82.07% fermentation efficiency. The outcome of the experiment shows that the Choline Chloride–Urea DES pretreatment could increase the cellulose accessibility which ultimately enabled the conversion of rice husks to bioethanol.]]>
