OPTIMIZATION OF PROCESS PARAMETERS IN ETHANOL PRODUCTION FROM CASSAVA WASTE SLURRY

C. B. Ugwuodo; E. N. Anike; H. Ukochukwu; K. Nwosu-Obieogu

C. B. Ugwuodo Department of Chemical Engineeering Michael Okpara University of Agriculture Umudike, Umuahia, Abia State
E. N. Anike Department of Chemical Engineeering Michael Okpara University of Agriculture Umudike, Umuahia, Abia State
H. Ukochukwu Department of Chemical Engineeering Michael Okpara University of Agriculture Umudike, Umuahia, Abia State
K. Nwosu-Obieogu Department of Chemical Engineeering Michael Okpara University of Agriculture Umudike, Umuahia, Abia State

Keywords: Cassava, Fermentation, Hydrolysis, Optimization, Yield

Abstract

The production of ethanol from renewable material is a sustainable avenue of ethanol production. This study focused on optimizing parameters affecting the production of ethanol generated from cassava waste slurry. The waste generated from cassava were characterized using proximate analysis. The proximate analysis results showed that the cassava waste slurry contain more moisture, volatile matter and fixed carbon. Central composite experimental design (CCD) was used to design and model the process with 50 experimental runs. CCD, with quadratic models explored the combined effect of five independent variables namely, temperature, PH, sugar concentration, time, and feed rate of the fermenting medium. The process parameters were optimized to obtain the optimal yield, purity and specific gravity. The experimental result showed that the maximum ethanol yield of 26% was obtained at a temperature of 400C, pH of 4, sugar concentration of 0.125, production time of 0.5hrs and feed value of 250ml. The statistical analysis of the yield, purity and specific gravity showed correlation coefficient (R2) of 0.88, 0.91 and 0.82 respectively. The effect of the process parameters showed that increase in the reaction temperature, feed, time, and pH increases the yield of ethanol while increase in the sugar concentration decreases the ethanol yield. The optimization result showed that the optimal yield of 10.54%, purity of 5.76% and specific gravity of 0.26 were obtained at reaction temperature of 30.06 ̊C, pH of 5.40, sugar concentration of 0.30ml/dm3 and reaction time of 1.03 hours.