KRAFT AND ALKALINE PULPING PROCESSES USING SYNERGISTIC COMPOSITION TO ENHANCE PULP YIELD

摘要

A compsn. for increasing the yield of paper pulp derived from lignocellulosic materials comprises:- (a) 0.01-1.5 wt.% anthraquinone, and (b) 0.01-10 wt.% of a divalent metal salt comprising Ca, Ba, Sr, Mg or Zn salt, based on the lignocellulosic material. Also claimed is a process for the delignification of lignocellulosic materials by treating the latter with an alkaline digesting liquor contg. the above compsn. and up to 50 vol.% of the spent liquor.