Effects of lignin content and acid concentration on the preparation of lignin containing nanofibers from alkaline hydrogen peroxide mechanical pulp

Abstract

The poplar alkaline hydrogen peroxide mechanical pulp (APMP) with the lignin content of 24.63 % was used as raw material, which with lignin content of 10.04 %, 6.33 %, 3.82 %, and 1.14 % were obtained by the acid sodium chlorite method for 1–4 hours respectively. Then, different lignin content APMP were micro-nano processing treated with acidolysis (6.5 M, 9.8 M) or ultra-granular grinding respectively. Afterwards, poplar bleached chemical pulp (BCP) was prepared micro-nano cellulose under the same conditions as the APMP. Then, compared the data of the particle size, specific surface area, fiber morphology and zeta potential of suspensions between micro-nano cellulose products. The results show that the presence of a small amount of lignin (1–4 %) in APMP does not affect the preparation of different scales nano cellulose under different acid concentration conditions. When the lignin content is reduced to below 2 %, the acidolysis is more uniform, stable, and well-dispersed compared to BCP products; when the APMP is processed by the ultra-granular grinding, the higher lignin content, the more obvious cutting effect in the fiber length direction. The characteristics and feasibility of the preparation of micro-nano cellulose by the acidolysis and ultra-granular grinding using APMP with varying degrees of delignification are compared.