One-Pot dry chemo-mechanical deconstruction for bioethanol production from sugarcane bagasse

• Vibratory (VBM), centrifugal (CM) and ball (BM) milling pretreatments were compared.
• VBM was most effective in the reduction of particle size and cellulose crystallinity.
• NaOH-BM and NaOH-VBM were preferred to enhance glucose and bioethanol yields.
• The highest energy efficiency was obtained with NaOH-CM.
• Dry NaOH-CM pretreatment appears the most suitable for bioethanol production from SB.

The aim of this study was the application of an innovative dry chemo-mechanical pretreatment using different mechanical stresses to produce bioethanol from sugarcane bagasse (SB). The effect of different milling methods on physicochemical composition, enzymatic hydrolysis, bioethanol production and energy efficiency was also evaluated. SB was pretreated with NaOH and H3PO4 at high materials concentration (5 kg/L). Results indicate that vibratory milling (VBM) was more effective in the reduction of particles size and cellulose crystallinity compared to centrifugal (CM) and ball (BM) milling. NaOH pretreatment coupling to BM and VBM was preferred to enhance glucose yields and bioethanol production, while CM consumed less energy compared to BM and VBM. Moreover, the highest energy efficiency (η = 0.116 kgglucose/kWh) was obtained with NaOH–CM. Therefore, the combination of dry NaOH and CM appears the most suitable and interesting pretreatment for the production of bioethanol from SB.