Optimization of Dilute Acid Pretreatment for Enhanced Release of Fermentable Sugars from Sugarcane Bagasse and Validation by Biophysical Characterization

Pretreatment of biomass is one the most challenging steps in process second-generation (2G) ethanol and biochemical production. Dilute acid pretreatment a widely adapted convenient method to recover pentose (C5) as well hexose (C6) sugars due its featured solubilization hemicellulose cellulose before after enzymatic saccharification, respectively. In present study, dilute sulfuric (H2SO4) sugarcane bagasse (SCB) was statistically optimized using face-centered composite design (FCCD) response surface methodology (RSM) terms concentration (0.1–3% v/v), solid loading (5–20% w/v) residence time (15–60 min) at constant temperature 121 °C followed by hydrolysis commercial cellulase (Novozymes Cellic CTec2) for enhanced combined sugar yield (CSY) comprising C5 C6 pretreated saccharified hydrolysates. Optimized parameters found study were 2.18% (v/v) acid; 14.35% (w/v) loading; 29.49 min time. CSY under conditions be 521.42 ± 7.2 g/kg raw SCB with 72.06 1.0% recovered out maximum theoretical biomass. Total reducing yields hydrolysates 215.28 2.4 306.14 5.3 SCB, Morphological structural changes further validated efficiency applied study. The concentration, volumetric productivity from released calculated 10.82 2.2 g/L, 0.45 0.9 g/L/h 0.42 g/g-glucose consumed or 71.45 2.5 Ethanol obtained fermentation H2SO4-pretreated corresponding 82.4% yield.