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So far, a large number of pretreatment methods have garnered significant attention aimed only at optimizing the reducing sugar and bioethanol yields. This study however, carried out pretreatment of sugarcane bagasse (SCB) using hydrothermal, organosolv, alkaline and alkaline peroxide pretreatment methods comparing their process performance. An evaluation of the energy consumption parameter during pretreatment showed lowest energy use (0.619 kWh/kg) during 5% alkaline peroxide pretreatment. The energy efficiency (0.162 kg bioethanol/kWh) was thus highest whereas the waste generation was lowest (38.895 kg waste/kg bioethanol) during alkaline peroxide pretreatment process. The solid biomass was utilized for enzymatic saccharification and bioethanol fermentation using SSF. Maximum enzyme efficiency and bioethanol yields achieved were 85.02% and 0.101 kg bioethanol/kg biomass respectively. Process performance evaluation can be projected to open up a new avenue for practical implementations of life cycle analysis (LCA) and techno-economic assessment aiding the circular bio-economy approach. [Display omitted] • Chemical pretreatment technologies investigated for process performance evaluation. • Energy efficiency and waste generation used to evaluate process performance. • 0.162 kg bioethanol/kWh- energy efficiency during alkaline peroxide pretreatment. • Also, lowest waste generation (38.895 kg waste/kg bioethanol) was recorded. • NaOH and H 2 O 2 at 5% (w/w) chemical concentration was most effective pretreatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • A ball-mill assisted alkaline peroxide pretreatment process was developed. • 70% of XOS alone with high yield of fermentable sugars was achieved. • The pretreatment process was environmental-friendly. • The mechanism of enhanced enzymatic digestibility by BAP pretreatment was revealed. The aim of this work was to develop a feasible ball mill-assisted alkaline peroxide pretreatment followed by stepwise hydrolysis to improve the yield of xylo -oligosaccharides (XOS) and fermentable sugars. The hydrogen peroxide charge, ball-milling time, and solid-to-liquid ratio affected the compositions, particle sizes, morphology, and crystallinity of the corn stover, directly improving the following hydrolytic efficiency. The optimal pretreatment was with 0.45 g/g (H 2 O 2 : substrate) and 1:3 solid-to-liquid ratio (w/v) for 1.0 h ball-milling, resulting in 84.29% delignification. Physicochemical properties of the pretreated samples were characterized and their correlations to the enzymatic hydrolysis were revealed. Compared with one-step cellulase hydrolysis, the two-step xylanase-cellulase hydrolysis of the pretreated corn stover showed significant advance in preparing XOS, producing 69.65% (on the base of xylan content in pretreated sample) of XOS, along with 20.55% xylose, 68.94% glucose, and 21.15% gluco -oligosaccharides. The yield of XOS was 2–7 times higher than those in previous studies. [ABSTRACT FROM AUTHOR]