USE OF ZEOLITES IN STABILISING ALKALINE PEROXIDE SOLUTIONS AND THEIR APPLICATION IN THE BLEACHING OF A TMP PULP

摘要

Silicate-based chemistry is a common industrial practice to improve peroxide bleaching, however, the transition metal ion-induced peroxide decomposition is still inevitable. In this study, we investigated the potential to further decrease the peroxide decomposition by adding zeolites to the silicate-based peroxide system. The peroxide decomposition results showed that the combined effect of zeolites and sodium silicate is more effective than sodium silicate alone in decreasing the manganese-induced peroxide decomposition. Two types of zeolites, X and Y, were studied. The bleaching experiments showed that an improved peroxide bleaching performance was obtained by adding Y-zeolites to the conventional peroxide process.