METHODS FOR CARBONATE PRETREATMENT AND PULPING OF CELLULOSICMATERIAL

摘要

A method of pretreating comminuted fibrous material with sodium carbonate and then cooking the pretreated material in the presence of anthraquinone ( AQ) is provided. The resulting pulp produced has a higher yield, enhanced st rength, and better bleachability compared to pulp produced by prior art meth ods. AQ may also be introduced to the carbonate pretreatment stage. The meth od may further include an acid pretreatment providing further enhanced prope rties to the pulp produced.