A new sight on the catalytic oxidation kinetic behaviors of bamboo cellulose fibers under TEMPO-oxidized system: The fate of carboxyl groups in treated pulps

Abstract

This article conducted an investigation on the selective oxidation of C6-OH in cellulosic chains during TEMPO-oxidized process of bamboo pulps under different conditions, from which the kinetic behaviors and model for describing the fate of carboxyl groups in treated pulps were studied. It was found that the end concentration of carboxyl groups in treated pulps is mainly affected by the time-dependent TEMPO and NaOCl concentration. Meanwhile, the NaBr dosage and process temperature could also affect the reaction rate of carboxylate generation. Based on the experimental data directly from the determination of carboxyl groups, the proposed kinetic model could describe the TEMPO oxidation process of bamboo pulps at various process conditions, and there is a good correlation (R2 = 0.9608) between the measured and predicted data. According to the model, a two-stage kinetic description with different orders about the carboxyl generation based on the modelling was firstly declared in this paper.