Abstract
•A new reactor design was developed for continuous pretreatment of biomass.•Hydrodynamic cavitation was successfully adapted for different operation modes.•Continuous process of sugarcane bagasse resulted in high sugars release.•Short time and milder conditions are required for continuous pretreatment.•High amount of biomass is processed per operation time in semi-continuous process.
Development of new technologies for pretreatment of lignocellulosic biomass is a current research challenge. In this way, hydrodynamic cavitation (HC) was used to assist alkaline hydrogen peroxide pretreatment of sugarcane bagasse (SCB) in sequential batches (SB-HC), semi-continuous (SC-HC) and continuous (C-HC) processes. Pretreatment resulted in compositional modifications in the material, mainly regarding the cellulose and lignin contents. The released sugars after enzymatic hydrolysis resulted, on average, in 42 g and 32–35 g of glucose per 100 g of SCB for samples treated in B-HC (10 min of process) and SC-HC process (7.5 min residence time), respectively. In C-HC process, with an average residence time of 7.5 min and 3.75 min, 38–46 g and 32–38 g of glucose per 100 g of SCB were obtained respectively in enzymatic hydrolysis step. HC technology was shown as a promising alternative for pretreatment of lignocellulosic biomass in all evaluated configurations aiming to produce high value bioproducts.