The aim of this work was to optimize the hydrolysis and fermentation of plantain peels. Kinetic study was also carried out. Proximate analysis of plantain peels was carried out and the result showed that it contains 46% cellulose. Aspergillus niger isolated and screened for cellulase activities was used as the crude enzyme for the hydrolysis and commercial available Saccharomyces cerevisae was used for the fermentation. The optimization was done using quadratic model of central composite rotatable design for both hydrolysis and fermentation. Analysis of variance ANOVA was used to test for the significance of the model and the factors. The results of the analysis showed that temperature, time, pH and the substrate concentration significantly affected the yield of simple sugar in the hydrolysis of plantain peels. The result equally showed that temperature, time and pH were significant factors of fermentation. The optimum conditions for the hydrolysis were 35˚C, 5 days, and pH of 5.5, substrate concentration of 8 g/30ml and glucose yield of 49%. Also the optimum conditions of fermentation were obtained as 30˚C, pH of 4.0, 9 days and ethanol yield of 19%. The Michaelis-Menten model adequately fit both the hydrolysis and fermentation kinetics.

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The adoption of aluminium sulfate and potassium sulfate as electrolyte additives were investigated to determine the possibility of enhancing the charge cycle of 2V/ 20AH lead acid battery with reference to the conventional dilute sulfuric acid electrolyte. The duration and efficiency of lead acid batteries have been a challenge for industries over time due to weak electrolyte and insufficient charge cycle leading to sulfation. This has affected the long-term production output in manufacturing companies that depend on lead acid batteries as alternative power source. Hence there is need to explore the use of specific sulfate additives that can possibly address this gap. The electrolyte solutions were in three separate charge and discharge cycles involving dilute sulfuric acid electrolyte, dilute sulfuric acid-aluminium sulfate mixed electrolyte and dilute sulfuric acid-potassium sulfate mixed electrolyte for one hour each. The total voltage after 30 minutes charge cycle was 2.3V, 2.35V and 5.10V for dilute sulfuric acid, aluminium sulfate additive and potassium sulfate additive respectively. The cell efficiency for dilute sulfuric acid, aluminium sulfate additive and potassium sulfate additive electrolytes are 77%, 77% and 33% respectively. The electrolyte sulfate additives were of no positive impact to the conventional dilute sulfuric acid electrolyte of a typical lead acid battery due to the low difference in potentials between the terminals.