ABSTRACT
Mechanical pulps may be bleached either by oxidative or reductive processes that remove colored chromophores [1,2]. In water, the reductive processes are limited by the strength of the chemical used, because highly reductive chemicals like metal hydrides (NaH and LiAlH4) also react with water. Other reducing agents have been extensively studied in the past, for example some metal cation like Cr2+ and U3+ [3,4], that can easily reduce chromophores and bleach lignin model compounds, are themselves colored and are not suited for the bleaching of pulp.
