Liquefaction and characterization of acid hydrolysis residue of corncob in polyhydric alcohols

Acid hydrolysis residue (AHR) of corncob was liquefied using glycerol as main liquefaction solvent. The effects of various liquefaction conditions such as reaction time, liquefaction temperature, catalyst content, ratio of polyol/AHR and glycerol concentration on the liquefied residue content have been studied in this paper. The liquefied product was separated into three fractions: a water-soluble part, an acetone-soluble part and a residue. Fourier transform infrared (FT-IR) analyses showed that the acetone-soluble part mainly included degradation products from lignin, the water-soluble fraction mainly contained liquefaction solvent and its derivate and cellulose degradation products, the residue mainly contained lignin derivatives. The gas chromatography and mass spectrometry (GC–MS) analyses showed that liquefied products of AHR included alcohols, acids, esters, alkanes, phenols and their derivatives.

► Acid hydrolysis residue of corncob was liquefied using glycerol as main liquefaction solvent.
► The effect of glycerol content on the liquefied residue content was studied.
► The compositions of the liquefied product obtained was analyzed after separating it into three parts.