NSSC pulp treatment with the Fenton reaction: fiber modification for reduced energy consumption in papermaking

Abstract The pulp and paper industry is focused on developing sustainable and energy-efficient production methods due to rising energy costs and environmental concerns. This study evaluates the Fenton reaction for modifying Neutral Sulphite Semi-Chemical (NSSC) pulp, applying varying dosages of Fenton chemicals followed by refining in a Jokro mill. Results indicate that the Fenton reaction reduced energy consumption during refining by up to 36 %, while maintaining similar pulp freeness. Under optimized conditions, tensile strength was enhanced by up to 10 % compared to untreated pulp at the same energy input. However, high chemical dosages caused significant fiber damage, leading to shorter fiber lengths and up to a 20 % reduction in burst index at a given pulp freeness. Low dosages achieved energy savings of up to 10 % without significantly compromising paper strength. Cationic starch was also applied to treated NSSC pulp to investigate if increased fiber charge or carboxylic groups would enhance its effect, but no significant benefit was observed. Instead, oxidative treatment led to a 25 % reduction in zero-span index at high dosages, indicating fiber weakening. Under specific economic conditions, such as high energy costs and low chemical prices, this approach could provide advantages in industrial applications.