An integrated biorefinery process for mandarin peel waste elimination

Mandarin peel waste, a representative agricultural waste, has been dumped on land and marine environments worldwide, causing significant environmental damage. Thus, a solution is urgently required to reduce direct dumping and convert mandarin peel waste into high value-added products. In this study, to achieve a zero-waste concept, an integrated biorefinery effectively reduced the mass of mandarin peel waste through consecutive processes that included washing, autohydrolysis, enzymatic hydrolysis, and melt compounding. This suggests that integrated biorefinery produced 92.4% of arabinose and arabinooligosaccharide by autohydrolysis and 81.9% of glucose by enzymatic hydrolysis using 5 filter paper unit of cellulase. Overall, the enzymatically hydrolyzed residue replaced 10% of polylactic acid for biocomposite production, which reached approximately 84% of the tensile strength level compared to that of neat polylactic acid. Finally, a concise economic assessment presents the feasibility of an integrated biorefinery by converting value-added products from mandarin peel waste to overcome the environmental and economic problems associated with direct dumping. [Display omitted] •Total utilization of mandarin peel was achieved via a zero-waste process.•Ethanol-washed mandarin peel (EWMP) was produced to improve storage performance.•Arabinan in EWMP was successfully isolated to hydrolysates by autohydrolysis (92.4%).•Glucose (81.9%) was obtained from autohydrolyzed EWMP with 5 FPU enzyme/g glucan.•PLA/mandarin peel lignin biocomposite showed 83.8% tensile strength compared to PLA.