Authors: Denilson da Silva Perez Adriaan van Heiningen
Publish Date: 2015/09/07
Volume: 22, Issue: 6, Pages: 3967-3979
Abstract
A method is described which allows prediction of alkaline pulp yield It is based on an equation which relates the pulp yield to the cellulose content and cellulose degree of polymerization of the alkaline pulp From the slope and intercept of this linear equation the ligninfree pulp yield textY textTprime of a pulp sample can be calculated when the ligninfree cellulose content textGprime and the cellulose degree of polymerization DP of the pulp fiber are determined by sugar analysis and viscosimetry respectively In this paper the yield prediction equation is derived and validated using model celluloses and hemicelluloses As part of the yield prediction method a new equation was developed which corrects the cellulose degree of polymerisation obtained from the pulp intrinsic viscosity for the hemicellulose content of the pulp The approach was successfully validated by cooking of cotton at different temperatures 160–180 °C alkalinities 130–260 mol/L the equivalent to an effective alkali as Na2O charge of 12–24 at a L/W ratio of 40 L/kg sulfidities 15 and 30 and anthraquinone charges 0 005 and 01 The cellulose protecting effect of AQ was confirmed by the lower number of glucose units removed by alkaline peeling compared to that removed during conventional alkaline or kraft cooking
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