Preparation and characterization of biomass-based nanocatalyst for hydrolysis and fermentation of catalytic hydrolysate to bioethanol

In this study, magnetic solid acid nanocatalyst was synthesized using Syzygium cumini seed powder and green synthesized magnetic Fe 3 O 4 nanoparticles by wet impregnation method. The catalyst with a high acid density of 0.85 mmol g −1 , the surface area of 466.905 m 2 g −1 , and pore volume of 0.191 cm 3 g −1 was obtained. The prepared nanocatalyst Fe 3 O 4 –@C–SO 3 H was used to hydrolyze ultrasonic pretreated palmyra peel and corncob biomass in a magnetic stirrer. The total reducing sugar (TRS) of 97.6% and 90% was achieved for palmyra peel and the later for corncob under varied conditions of catalyst concentration and temperature. It is observed at 0.3-g catalyst concentration and 125 °C temperature gave the best yield for the palmyra peel sample within 1 h. And for corncob samples at 0.2-g catalyst concentration and 135 °C gave the best sugar yield within 1 h. The hydrolysate comprising high reducing sugar was further fermented using Saccharomyces cerevisiae . Bioethanol yields of 78.3% from palmyra peel and 62.7% from corn cob were quantified using gas chromatography technique.