Liquefaction and characterization of residue of oleaginous yeast in polyhydric alcohols

The residue of oleaginous yeast (ROY) was liquefied in polyhydric alcohols using sulfuric acid as catalyst. The effects of some liquefaction conditions on the liquefied residue rate, such as liquefaction temperature, catalyst loading, reaction time, glycerol concentration and solvent/ROY ratio, were discussed. The liquefied residue rate decreased as the reaction time, liquefaction temperature, catalyst loading, solvent/ROY ratio increased. The re-polymerization of liquefied products was favored in later stage reaction. Higher catalyst loading and lower solvent/ROY ratio could accelerate the re-polymerization of liquefied products; thus the liquefied residue increased. Fourier transform infrared (FT-IR) analyses showed that the main component of ROY is polysaccharide. The gas chromatography and mass spectrometry (GC-MS) analysis showed that liquefied products of ROY included alcohols, acids, ketones, aldehydes, amide, ester and their derivatives.