Oxygen bleaching process for cellulocis pulps with a polyhydric alcohol cellulose protector

An improved oxygen bleaching process for bleaching cellulosic pulp comprising mixing said pulp with an aqueous medium containing a polyhydric alcohol cellulose protector and caustic to uniformly distribute the caustic and protector throughout the pulp to form a treated pulp, said polyhydric alcohol being selected from the group consisting of ethylene glycol, propylene glycol, glycerol, pentaerythrytol and diethylene glycol, passing said treated pulp in said aqueous medium into said oxygen bleaching stage, said aqueous medium in said oxygen bleaching stage containing between 10% and 70% by weight of said polyhydric alcohol and sufficient of said caustic to obtain the desired reduction in kappa no. during said oxygen bleaching stage, bleaching said pulp with oxygen in said oxygen bleaching stage in an oxygen atmosphere in said aqueous medium containing said caustic and between 10% and 70% by weight of said polyhydric alcohol at a pressure to obtain oxygen bleaching and produce an oxygen bleached pulp having a higher viscosity than a similar softwood pulp oxygen bleached to the same kappa no. using the same conditions but in water substantially free of cellulose protectors.