... carried out according to the Kraft (sulfate) or sulfiteprocesses [13]. These methods are described in the following subsections.Kraft PulpingKraft pulping involves the cooking of wood chips ... classified as the physico-chemical and biological treatment methods. These technologies are discussed in the following subsections. 10. 10.1 Physico-Chemical ProcessesSeveral physico-chemical methods ... (TCF), and biobleaching aredescribed in subsection 10. 9.2. 10. 6.1 Compounds Formed during Chlorine Bleaching Process During pulp bleaching, lignin is extensively modified by chlorination (C stage)...