Kinetic Modelling of Bioethanol Production from Sugarcane Bagasse in Niger State Using Optimised Pretreatment Methods

This study develops kinetic models for bioethanol production from sugarcane bagasse in Niger State, North Central Nigeria, examining the effect of pretreatment method optimisation on fermentation efficiency and ethanol yield. Nigeria's sugarcane industry in Niger and Kebbi States generates large volumes of bagasse that currently have limited value use. Bioethanol production from bagasse lignocellulose offers both energy and economic value from an otherwise waste material, supporting Nigeria's biofuel production goals. This study compares three pretreatment methods, namely alkaline, dilute acid, and steam explosion, for cellulose digestibility improvement before enzymatic hydrolysis and fermentation. Enzymatic hydrolysis is conducted using commercial cellulase cocktails, and fermentation uses Saccharomyces cerevisiae. Kinetic parameters including maximum glucose yield, hydrolysis rate constants, ethanol yield coefficient, and fermentation rate are determined from time series data. Response surface methodology optimises pretreatment conditions for maximum cellulose conversion efficiency. Findings reveal that steam explosion at 180 degrees Celsius for 10 minutes achieves the highest cellulose conversion of 78 percent, followed by alkaline pretreatment at 72 percent. Ethanol yield from optimised steam-exploded bagasse reaches 0.42 grams ethanol per gram glucose, close to theoretical maximum. The Monod kinetic model fits the fermentation data with high accuracy. The study contributes original kinetic modelling data for Nigerian sugarcane bagasse bioethanol and recommends pilot-scale bioethanol facility development in Niger State as a bioenergy investment priority.

Keywords: bioethanol, sugarcane bagasse, kinetic modelling, pretreatment, Niger State.