INFLUENCE OF THE OPERATING VARIABLES USED IN THE O STEP OF THE XOP BLEACHING SEQUENCE OF SODA PULP FROM WHEAT STRAW ON THE QUALITY OF BLACK LIQUOR

摘要

Black liquor obtained in the bleaching with the cartazyme anzime - oxygen - hydrogen peroxide (XOP) sequence of soda pulp from wheat straw was characterized. A central composite design was used to examine the influence of operating variables of the O bleaching step (temperature, time and soda concentration) on various properties of the black liquor (pH, chemical oxygen demand, total carbon, total organic carbon, total inorganic carbon, total solids, total volatile solids, total mineral solids and colour).