Open AccessProduction of Bioethanol using Waste Fruits under Acid and Alkali Catalytic Hydrolysis: A Review
Author(s) -
S.J. De Silva,
Udara S.P.R. Arachchige,
A.H.L.R. Nilmini
Publication year - 2021
Publication title -
asian journal of chemistry/asian journal of chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.145
H-Index - 34
eISSN - 0975-427X
pISSN - 0970-7077
DOI - 10.14233/ajchem.2022.23466
Subject(s) - biofuel , hemicellulose , raw material , waste management , chemistry , pulp and paper industry , ethanol fuel , fermentation , cellulosic ethanol , cellulose , environmental science , food science , engineering , organic chemistry
The present world highly depends on petroleum fuels to gain energy for transportation resulting in thevast side of environmental problems such as global warming and air pollution. Due to this, the price ofconventional fuel escalating day by day. Accordingly, the world needs renewable, ecologically suitable,cost-effective alternate against fossil fuels. Bioethanol is one of the most usable fuel or fuel additivesamong the other biofuels. Ingoing qualities of bioethanol such as high-octane number, high oxygencontent, and low energy content are revealed that application of bioethanol produced from differenttypes of waste materials feedstock in the transportation and energy sector diminishes environmentpollution. It provides a solution for waste management. The world releases a considerable amount offruits as waste annually. Thereby, fruit waste is the cheapest feedstock to produce bioethanol. Fruitwaste such as whole rotten fruits, fruit peels, seeds and other residues consists of cellulose,hemicellulose, lignin, starch and simple sugars. Conversion of cellulose and hemicellulose to ethanolis vital to advance pretreatment and hydrolysis techniques to obtain maximum ethanol content. Theproduction process of bioethanol from fruit waste mainly contains pretreatment; hydrolysis,saccharification, fermentation and ethanol extracting process (distillation) steps. Yeast (S. cerevisiae)is primarily used in the fermentation process because of its high conversion efficiency, cost-effectivenessand feasibility of handling. Considering the optimum configuration for bioethanol production,simultaneous saccharification and fermentation (SSF) is the best commensurate method havingmaximum bioethanol concentration. The fermentation process could be appreciated through variousfactors, such as temperature (30-33 ºC), pH of the medium (4-5), time of incubation, feedstockconcentration, inoculum size, agitating rate, N sources in the medium to gain high bioethanolconcentration.