Production of hemicelluloses sugars, cellulose pulp, and lignosulfonate surfactant using corn stalk by prehydrolysis and alkaline sulfite cooking

Abstract

Full components utilization of corn stalk was investigated by the combine processes of prehydrolysis and alkaline sulfite cooking. Prehydrolysis was employed to remove hemicelluloses prior to cooking. Glucose yield of 76.8 g/kg and xylose yield of 118.4 g/kg corn stalks were obtained from the hydrolysis of hemicelluloses at 150 °C for 3 h. Significantly, cellulose was largely preserved during prehydrolysis as indicated by the pulp yield from 54 % to 62 % from the alkaline sulfite cooking. Paper sheet showed superior physical strength over hardwood pulp, e.g. tensile index 97.4 N·m/g, tear index 6.6 mN·m2/g and burst index 5.2 kPa·m2/g. In addition, lignin in spent liquor of alkaline sulfite cooking was recovered as lignosulfonate surfactant which reduced the surface tension of water to 38.2 mN/m at a concentration of 15 g/L. The combined processes of prehydrolysis and alkaline sulfite cooking enables full utilization of cellulose, hemicelluloses, and lignin, and therefore has great potential to industrial application.