Effects of chemical inhomogeneity of corn stalk on solvolysis liquefaction

Structural characterization of corn stalk (CS) factions including whole stalk, ear husk, leaf blade, stem bark and stem pith was conducted. Different fractions were liquefied by solvolysis liquefaction method. Acid number, hydroxyl number and insoluble residues ratios (IRR) of liquefied products from CS factions were monitored. Results showed chemical compositions of CS fractions had remarkable difference. Cellulose, hemicellulose and lignin accounted for 36.9-41.43%, 21.77-37.3% and 3.38-7.52% of the raw material, respectively. Acid numbers increased with increasing time from 30 to 90 min, whereas hydroxyl numbers decreased gradually, IRR decreased and then increased. However, properties of liquefied products differed remarkably. Higher acid number, higher hydroxyl number, and lower IRR were detected from ear husk liquefied products. This is coincident with the higher content of hemicelluloses in ear husk. This work proved that whole utilization process is unsatisfactory in solvolysis liquefaction and different fractions of CS should be given themselves optimum applications.