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Magnetic hybrid hydrogels with a novel polymeric coating consisting of chitosan and cellulose were prepared. By coating cellulose and chitosan, we combined the renewability and biocompatibility of cellulose and chitosan as well as the magnetic properties of Fe(3)O(4) to create a hybrid system to adsorb heavy metals.

Graphene oxide obtained by the Hummers method was discovered to be an efficient and recyclable acid catalyst for the conversion of fructose-based biopolymers into 5-ethoxymethylfurfural (EMF). EMF yields of 92%, 71%, 34% and 66% were achieved when 5-hydroxymethylfurfural (HMF), fructose, sucrose and inulin were used as starting materials, respectively.

Cellulose nanocrystals (CNCs) as a renewable and biodegradable nanomaterial have wide application value. In this work, CNCs were extracted from bleached chemical pulp using two stages of isolation (i.e. formic acid (FA) hydrolysis and 2,2,6,6-tetramethyl-piperidine-1-oxyl (TEMPO) mediated oxidation) under mild conditions. In the first stage, FA was used to remove hemicellulose, swell cellulose fibers, and release CNCs. The FA could be readily recovered and reused. In the second stage, the CNCs isolated by FA were further modified by TEMPO-mediated oxidation to increase the surface charge of CNCs. It was found that the modified CNCs with more ordered crystal structure and higher surface charge had better redispersibility and higher viscosity in aqueous phase. Therefore, the modified CNCs could be more effective when used as rheology modifier in the fields of water based coating, paint, food etc.

The conversion of biomass-derived 5-hydroxymethylfurfural (HMF) was examined over Ni–Co–Al mixed oxide catalysts derived from corresponding hydrotalcite-like compounds (HTlcs). 1,2,6-Hexanetriol (1,2,6-HT) was obtained in 64.5% yield under mild reaction conditions. The catalysts were characterized by X-ray powder diffraction (XRD), CO2 temperature-programmed desorption (CO2–TPD), N2 physical adsorption, and H2 temperature-programmed reduction (H2–TPR), and the reaction product distribution was correlated with the catalyst composition and reaction conditions. The reaction pathway was proposed based on the results. In all cases, the conversion of HMF proceeds according to a pathway that begins with the aldehyde group being hydrogenated to form 2,5-dihydroxymethylfuran (2,5-DHF). This product then undergoes a ring-opening reaction to form 1,2,6-HT. A synergetic effect between Ni and Co was observed, which significantly promoted catalytic activity and selectivity.

In this work, a sustainable and green process to prepare nanocrystalline cellulose (NCC) from bleached hardwood pulp was demonstrated. Rod-like nanocrystalline cellulose with the size of 15-40 nm in width and hundreds of nanometers in length was obtained through H3PW12O40 (HPW)-catalyzed hydrolysis of bleached pulp fibers under the mild reaction conditions. Thermogravimetric analysis revealed that the resulting NCC exhibited much higher thermal stability than the partially sulfated NCC (prepared by sulfuric acid). In addition, the concentrated HPW could be easily recovered and recycled through the extraction with diethyl ether, and the recovered HPW could be reused for several rounds of cellulose hydrolysis without activity lost. These fundamental studies are of crucial importance for the development and application of NCC products/NCC-based biomaterials with good thermal stability.

Cellulose nanocrystals (CNCs) can be used as building blocks for the production of many renewable and sustainable nanomaterials. In this work, CNCs were produced from bleached eucalyptus kraft pulp with a high yield over 75 % via FeCl 3 -catalyzed formic acid (FA) hydrolysis process. It was found that the particle size of resultant CNC products (F-CNC) decreased with the increase of FeCl 3 dosage in FA hydrolysis, and a maximum crystallinity index of about 75 % could be achieved when the dose of FeCl 3 was 0.015 M (i.e. about 7 % based on the weight of starting material). Thermogravimetric analyses revealed that F-CNC exhibited a much higher thermal stability (the decomposition temperature was over 260°C) than S-CNC prepared by typical sulfuric acid hydrolysis. In the FeCl 3 -catalyzed FA hydrolysis process, FA could be easily recovered and reused, and FeCl 3 could be transferred to Fe(OH) 3 as a high value-added product. Thus, the FeCl 3 -catalyzed FA hydrolysis process could be sustainable and economically feasible. In addition, F-CNC could be well dispersed in DMSO and its dispersibility in water could be improved by a cationic surface modification.

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