The results on total fiber charge of fully bleached SW kraft pulps demonstrated that fiber charge decreased from an initial 95.9 μmol/g to a final 32.0-43.0 μmol/g as the pulp bleached to ～88% brightness via typical sequential bleaching. A second alkaline extraction stage in the bleaching sequence did not lead to a pulp brightness increase but caused 10.9-15.0% of total fiber charge reduction, which was retained while removing the second alkaline extraction stage. Hydrogen peroxide could be used to increase fiber charge 20.0 % by employing it at the last stage following a post-chlorine dioxide bleaching as OD(EPO)DP instead of OD(EPO)DD.
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