Production of Bioethanol from Rotten Watermelon (Citrullus lanatus) and Banana (Musa sapientum) Using Enzymatic Approach

Abstract

Fossil fuels have been a major source of energy for our life, but this vital role has been overshadowed by the risks these emissions pose to the ecosystem. A sufficient biomass supply must be used if this form of energy from biological mass is to be supported adequately. This work thus was carried out with a view of utilizing some locally available biomass wastes as alternative sources of ethanol. The samples (watermelon and Banana) were pre-treated (washed thoroughly) using distilled water to obtain right fermentable sugar hydrolysates. The substrates were then subjected to enzymatic hydrolysis. Fermentation took place with the aid of Sacchromyces cerevisea as the fermentation organism with optimisation of the reaction by fermenting with two strains of saccharomyces cerevisiae (baker′s yeast and freshly isolated yeast). Fermentation was allowed for about 5 days after which ethanol was recovered by distillation (at 78^oC). Confirmatory test such as flammability test, density, specific gravity, refractive index, boiling point and Fourier Transform Infrared Spectroscopy (FTIR) were conducted to ascertain the presence of right bioethanol extract. The use of the two substrates (water and banana) in bioethanol production was compared. The results showed that both substrates yielded sufficient amounts of bioethanol, with the rotten banana being more efficient. The rotten banana yielded higher quantities of bioethanol (13.17%) than the rotten watermelon (10.36%). In an effort to lower cost and improve yield, purity and turnaround time for these biofuels, efforts should be made to employ additional organic waste and to pursue further process optimisation solutions.