Ultrasound assisted metal chloride treatment of sugarcane bagasse for bioethanol production. (December 2016) - Ramadoss, Govindarajan
Abstract: This study presents the ultrasound assisted metal chloride treatment of sugarcane bagasse (SCB) for bioethanol production. The operating parameters pertaining to pretreatment and enzymatic saccharification were optimized. The ultrasound assisted FeCl3 pretreatment (UAFP) showed the maximum cellulose recovery and delignification of 94.94 and 79.42%, respectively, at the optimum conditions (particle size 0.274 mm, H2 O2 concentration 1.5% v/v, substrate dosage 3 g, ultrasound time 75 min, molar ratio of FeCl3 and H2 O2 1:100 and temperature 60 °C). Enzymatic saccharification of SCB obtained from UAFP showed 96% glucan digestibility (DG ) with 15 FPU cellulase and 30 IU β-glucosidase. The hydrolyzate obtained was fermented using Saccharomyces cerevisiae and about 93% theoretical ethanol yield was achieved at the end of 72 h of fermentation. The structural changes of native and pretreated SCB were investigated by Fourier transform infrared spectroscopic analysis (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM). Graphical abstract: Highlights: Ultrasound assisted metal chloride pretreatment of SCB was carried out. Ultrasound assisted FeCl3 pretreatment showed better performance. The maximum theoretical ethanol yield of 93% was achieved.