Search

Abstract: In this paper, some key parameters, such as the system pH, the periodate concentration, and the reaction temperature, on the influence of the bagasse fiber degradation were studied based on the oxygenant of periodate. And the feasible reaction mechanism was also discussed through the FTIR characterization for bagasse fiber before and after the oxidizing reaction. As the results shown, the crystallinity of bagasse fiber decreased with the oxidation level increasing. It was interesting that the aldehyde content of the reaction system rose gradually along with cellulose degradation. Based on this result, the selective oxidation kinetics was constructed by introducing of variable factor R (the ratio of aldehyde content to the degradation of cellulose fiber), and the results shown that there was a better correlation between the dynamic model and the experimental data, so the oxidation degree of bagasse fiber oxidized by periodate can be quantitative evaluated based on this model. [Copyright &y& Elsevier]

• Cellulose fibers were separated from licorice residues by pulping and bleaching. • Cellulose nanofibril from licorice residues was got by enzymatic hydrolysis method. • Effects of enzymatic pretreatment on CNF were investigated. • ETCNF showed clear nanofibrillar structure and good colloidal stability. • Chitosan nanofibril and lignin nanoparticles were incorporated into ETCNF films. It is important to make full utilization of industrial biomass residues. Pulp was prepared from licorice residues by soda-anthraquinone pulping followed by peroxyacetic acid bleaching. Cellulose nanofibril was obtained by enzymatic pretreatment followed by homogenization of the pulp (ETCNF). The effects of enzymatic pretreatment on ETCNF were investigated. Chitosan nanofibril (CHN) and lignin nanoparticles (LNPs) were prepared and used for ETCNF composites, respectively. The results showed that ETCNF exhibited clear nanofibrillar structure and a highly relative colloidal stability, and a much higher crystallinity index and thermal stability compared to TEMPO-medicated oxidized one; the cellulose composite films incorporated with CHN or LNPs exhibited good thermal stability and hydrophobicity. Compared with ETCNF film, ETCNF@LNPs-5.0% film showed higher UV-blocking ability and thermal stability, but reduced light transmittance, while ETCNF@CHN-5.0% film showed improved mechanical properties and similar light transmittance. This study would expend licorice residues as potential materials for CNF and its applications. [ABSTRACT FROM AUTHOR]

• Purification of hemicellulose by an Aromatic-Selective Adsorptive Resin. • Lignin removal rate could reach 89.2%. • Improving the purity of hemicellulose without affecting other properties. • Important for improving the separation and purification process of hemicellulose. Alkaline extraction of hemicellulose from lignocellulosic materials is an efficient separation method but also extracts polysaccharides with high proportions of lignin. In this study, aromatic-selective adsorption resin was used to the remove lignin in the purification of alkaline-extracted hemicellulose from sugarcane bagasse. The content of lignin in the alkaline extracted hemicellulose decreased and the removal rate reached 89.2% at 1/10 wt ratio of lignin to resin. Resin treatment led to a slight loss of hemicellulose but had a minute effect on its molecular weight and structure. The 2D heteronuclear single quantum coherence (HSQC) NMR analysis of adsorbates suggested that the decrease in carbohydrate contents in the extract resulted from the removal of the lignin-carbohydrate complexes (LCCs) during the resin treatment. It was concluded that the resin treatment had a minute effect on the properties of hemicellulose and could significantly improve its separation and purification. [ABSTRACT FROM AUTHOR]