INDIVIDUAL AND INTERACTIVE EFFECTS OF PEROXIDE PRETREATMENT VARIBLES ON SACCHARIFICATION AND ETHANOL YIELD IN BAGASSE

Abstract

The current experiment aimed to find the ideal pretreatment process parameters for maximize the yields of cellulose, fermentable simple sugars, and ethanol from bagasse that had successfully treated with hydrogen peroxide (H2O2). The pretreatment process variables like substrate concentration, H2O2 concentration, pretreatment time, and temperature were studied individually and in combination to see how they affected the response variables like cellulose, hemicellulose, and lignin content in the pretreated pulp. This was done using the response surface methodology (RSM). The best pretreatment conditions for sugar cane bagasse were found through experiments using a factorial central composite design (CCD). The highest cellulose and hemicellulose yields, which were determined by RSM to be 69.3% and 76.4%, respectively, with a lesser lignin yield (4.8%), were achieved at a substrate concentration of 2%, an H2O2 loading of 20%, a temperature of 120 oC, and a pretreatment duration of 120 min. The experimental actual and predicted outcomes were well correlated, demonstrating that the model may be applied to effectively pretreat lignocellulosic biomass. The model has been validated when there is no difference between experimental actual values and anticipated values. The modifications in the chemical structure of bagasse during pretreatment was analyzed using FTIR. Comparatively, samples processed with H2O2 had a higher crystallinity (CI = 23.63%) than untreated bagasse (CI = 15.84%). The loss of lignin, which contributed the greatest CrI, increased the proportion of cellulose in treated bagasse compared to untreated bagasse. The bagasse that had a H2O2 concentration pretreatment showed the highest reducing sugar yield (58.7 mg/g). Pretreated bagasse had a higher ethanol output (73.88 g/L) than untreated bagasse (45.49 g/L).