The effect of treating pine regular kraft pulp with peracetic acid before O2-delignification on the consumption of ClO2 in D0ED1 bleaching

Abstract

Effects of pre-treating pine kraft pulp kappa number 31.5 with peracetic acid (Paa) (0.33% and 0.66% as active oxygen based on oven-dried pulp) before O2-delignification were studied relative to the consumption of chlorine dioxide in a subsequent Elemental Chlorine Free (ECF) bleaching process. The study showed that such pre-treatment is an effective way to extend the delignification of the pine pulp and to reduce the consumption of chlorine dioxide required to bleach the pulp to a brightness of 87%. The reduction in chlorine dioxide required to bleach the pine pulp depended on the amount of Paa used for pre-treatment. Furthermore, the research showed that decreasing the kappa number of the pine pulp to approximately 7.5 units (with Paa pre-treatment and lengthening of O2-delignification process) caused an over-proportional reduction (by approximately 62.5%) in chlorine dioxide consumption to bleach the pulp to 87% brightness.

The enhanced selectivity of oxygen delignification of kraft pine wood pulps: The effects of pentosane-based cherry and guar gum additions

“…Pretreatments (Danielewicz, 2023), reinforcement (Peşman et al 2010), two-stage applications (van Heiningen et al 2018), catalysis (Suchy and Argyropoulos, 2002) and selectivity-enhancing additives (Gümüşkaya et al, 2011) have been extensively studied to understand their impact on the selectivity, e ciency, and mechanisms of OD process. Although modi cations for OD process offer advantages such as limiting environmental pollution and minimizing chemical usage, they also normally lead to additional challenges and expenses.…”