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This work describes a relatively simple methodology for efficiently deconstructing cellulose into monomeric glucose, which is more easily transformed into a variety of platform molecules for the production of chemicals and fuels. The approach undertaken herein first involves the dissolution of cellulose in an ionic liquid (IL), followed by a second reconstruction step aided by an antisolvent. The regenerated cellulose exhibited strong structural and morphological changes, as revealed by XRD and SEM analyses. These changes dramatically affect the hydrolytic reactivity of cellulose with dilute mineral acids. As a consequence, the glucose yield obtained from the deconstructed-reconstructed cellulose was substantially higher than that achieved through hydrolysis of the starting cellulose. Factors that affect the hydrolysis reaction include the type of cellulose substrate, the type of IL used in pretreatment, and the type of acid used in the hydrolysis step. The best results were obtained by treating cellulose with IL and using phosphotungstic acid (0.067 mol L(-1) ) as a catalyst at 413 K. Under these conditions, the conversion of cellulose was almost complete (>99%), with a glucose yield of 87% after only 5 h of reaction.

We studied the acid hydrolysis of cellulose in an aqueous medium with the aim of maximizing glucose yield and minimizing the formation of by-products. The influence of reaction parameters such as temperature, acid concentration, acid strength and type of cellulose precursor on glucose yield was investigated. We observed that moderate reaction temperature and low acid concentration resulted in the highest glucose yield with little formation of levulinic acid. Strong acid (pKa < 0) is required to achieve high glucose yield. The crystallite size of the cellulose also affects its reactivity; cellulose with higher crystallite size is more resistant to hydrolysis catalyzed by acid. The highest selectivity for glucose over levulinic acid was recorded at a reaction temperature of 413 K and a sulfuric acid concentration in the range of 0.2-0.5 mol/L. Under these reaction conditions, no levulinic acid was detected, but the glucose yield reached 20% in only 2 h.

The isomerization reaction of glucose to fructose was studied using five selected metal-organic frameworks (MOFs) as catalysts and a mixture of γ-valerolactone and 10% H2O as the solvent. MOFs with...

Silica-supported catalysts of nickel, cobalt, iron, molybdenum, and tungsten metal phosphides (NiP/SiO2, CoP/SiO2, FeP/SiO2, MoP/SiO2, and WP/SiO2) with a metal-loading of 15 wt%, were synthesized by reduction of the corresponding phosphite precursors. The catalysts were characterized by N2 adsorption-desorption, X-ray diffraction (XRD), CO pulse chemisorption, NH3 temperature programmed desorption (NH3-TPD), and X-ray photoelectron spectroscopy (XPS). The activity of these catalysts was measured at 573 K, a liquid flow of 0.3 mL•min-1 , a pressure of 2.0 MPa and a H2/liquid ratio of 300 in a three-phase, trickle-bed reactor in the hydrotreatment of methyl laurate. The MoP/SiO2 catalyst was found to exhibit the best catalytic performance based on its higher active phase dispersion as measured by XRD, CO chemisorption and XPS analyses, along with its moderate acidity, which is higher with respect to the other studied catalysts. The reaction conditions using the MoP/SiO2 catalyst, the most active and selective to C12 and C11 hydrocarbons, were optimized. Optimal results can be obtained under the following conditions: 573 K, 2.0 MPa, and a liquid flow of 0.3 mL•min-1. Moreover, long-run experiments showed that the MoP/SiO2 catalyst exhibits stable catalytic behavior for at least 96 h.