METHOD OF BLEACHING ALKALI PULP

摘要

PROBLEM TO BE SOLVED: To provide a method of bleaching pulp, capable of effectively removing lignin and color substance in alkali pulp, producing a pulp having high whiteness and high strength absolutely without using chlorine and perfectly preventing the generation of organic chlorine compounds such as chlorinated dioxin and chloroform. SOLUTION: An alkali pulp is treated under acidic condition to reduce the transition metal ion in the pulp, a stabilizer is added to the system while keeping the acidic state to stabilize the reduced transition metal ion, the pulp is bleached by mixing hydrogen peroxide and the bleaching is continued with or without adding oxygen after returning the pulp to an alkaline state.