Preparation of biopolyol by liquefaction of palm kernel cake using PEG#400 blended glycerol

•Palm kernel cake was solvothermally liquefied to prepare biopolyols.•The biopolyols were produced with 92.8% biomass conversion at optimal condition.•Hydroxyl and acid numbers of biopolyols were 236 mg KOH/g and 19 mg KOH/g.•The biopolyol was proved to be suitable for polyurethane synthesis based on FTIR analysis.

Palm kernel cake was solvothermally liquefied to prepare biopolyols. The liquefaction solvent was polyethylene glycol 400 (PEG #400)-blended glycerol and sulfuric acid was used as the catalyst. The optimal liquefaction conditions for biopolyol production were determined to be PEG#400/glycerol = 9/1, 15%(w/w) biomass loading, 3%(w/w) acid loading, and liquefaction at 150 °C for 90 min. The optimal conditions yielded 92.8% biomass conversion. The hydroxyl and acid numbers of biopolyol at optimal conditions were 236 mg KOH/g and 19 mg KOH/g, respectively. Fourier transform infrared spectroscopy showed that the resulting biopolyol was a suitable monomer for polyurethane synthesis.