Organic amine catalytic organosolv pretreatment of corn stover for enzymatic saccharification and high-quality lignin

•Organic amine catalytic organosolv pretreatment was developed.•High yield of monosaccharide was obtained after pretreatment and enzymatic hydrolysis.•High-quality and salt-free lignin was produced from pretreatment.

A novel and efficient organic amine and organosolv synergetic pretreatment method was developed to overcome the recalcitrance of lignocellulose to produce fermentable sugars and high-quality salt-free lignin. After optimization of the process parameters, a delignification of 81.7% and total sugar yield of 83.2% (87.1% glucose, 75.4% xylose) could be obtained using n-propylamine (10 mmol/g, biomass) as a catalyst and aqueous ethanol (60%, v/v) as a solvent. The susceptibility of the substrates to enzymatic digestibility was explained by their physical and chemical characteristics. The physical structure of extracted lignin showed higher β-aryl ether bonds content and functionalities, offering the potential for further downstream upgrading. The role of organic amine catalyst and a synergistic mechanism is proposed for the present system.

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