Effect of hydrogen peroxide bleaching duration on Sesbania grandiflora pulp

Abstract

Chlorine-based bleaching agent can brighten the pulp effectively, but it harms the environment, especially water pollution. Thus, hydrogen peroxide, a total chlorine-free (TCF) bleaching agent is applied in this research to bleach pulp derived from Sesbania grandiflora. Sesbania grandiflora is being chosen as raw material due to its ideal characteristics as pulp source and native in Malaysia. This research aims to determine the effects of hydrogen peroxide on Sesbania grandiflora pulp and evaluate the paper properties made from Sesbania grandiflora pulp. The research was carried under different bleaching durations, 20 minutes, 40 minutes and 60 minutes under a constant temperature of 50°C and 3% concentration of hydrogen peroxide. The physical, optical and mechanical properties of Sesbania handsheet were measured according to the standard TAPPI. The overall result presented a significant effect on kappa number and handsheet brightness but little on mechanical properties. The longer bleaching duration gave the least kappa number of the Sesbania pulp, thus, improving the brightness of the Sesbania handsheet. However, it did not affect the strength properties of the handsheet. In this research, 60 minutes of bleaching duration on Sesbania grandiflora pulp exhibits the optimal bleaching performance without compromising paper mechanical properties significantly.