MODIFICATION AND APPLICATION OF HEMICELLULOSE SEPARATED FROM WASTE LIQUOR OF PRC-APMP

摘要

The hemicelluloses, separated from PRC-APMP pulping waste liquor, were modified through etherifying reaction to get cationic quaternary ammonium type hemicelluloses with different degrees of substitution (DS). Some key factors to the modification were determined, including the dosages of etherifying agent and catalyst, reaction temperature and time, etc. The results showed that cationic hemicellulose with a relatively high DS of 0.083 could be obtained when the optimum conditions were as follows: mass ratios for cationic etherifying agent to hemicellulose and catalyst to hemicellulose were 1.0 and 0.06, respectively; the reaction temperature was 65 oC and the reaction time was 4hr. The cationic hemicellulose obtained was further used to improve the strength properties of hardwood kraft pulp, softwood kraft pulp and OCC, and they can be improved significantly.