Studies on enhancement of bioethanol production from sago and paper industrial solid residues by thermo chemical and biological hydrolysis using isolated microbes

Abstract

As a consequence of heightened concern for the greenhouse effect, depleting oil reserves and skyrocketing oil prices, renewable fuels, such as bioethanol are becoming increasingly important. Solid waste generated from sago and paper industrial sources are heterogeneous in composition, ranging from organic to inorganic while, sago industrial solid residues contain rich organic compounds, the paper industry solid residues contain both organic and inorganic compounds. Since the above industries create huge problems to the environment in Erode district, Tamil Nadu (India), they were selected for the study. The studies on pretreatment of the cassava peel residue (CPR) reveal that for an alkali concentration of 5 % at 40°C for a reaction period of 90 minutes, the maximum monosaccharide yield was around 44.58 ± 0.25 mg/g. The studies on pretreatment of the paper fiber residue (PFR) reveal that for an acid concentration of 0.5% at 110°C for a reaction period of 10 minutes, the maximum monosaccharide yield was around 85.43±0.29 mg/g. Further studies were carried out on the hydrolysates obtained after DAcH SE/ DAlH-SE under optimized conditions by biological hydrolysis viz. separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF). It could be concluded that combined treatment of diluted alkali hydrolysis with steam explosion followed by separate hydrolysis and fermentation using isolated fungi from waste fruits is suitable for enhancement of bioethanol from sago industrial solid residues. Similarly combined treatment of diluted acid hydrolysis with steam explosion followed by separate hydrolysis and fermentation using isolated bacteria from indigenous beverages is suitable for enhancement of bioethanol from paper industrial solid residues. newline newline newline