Magnetic Poly(Vinylsulfonic-<i>co</i>-Divinylbenzene) Catalysts for Direct Conversion of Cellulose into 5-Hydroxymethylfurfural Using Ionic Liquids

Abstract

Mesoporous poly(vinylsulfonic-co-divinylbenzene) (VS-DVB) and magnetic polymer (VS-DVB/CoFe 2 O 4 ) are prepared and used as solid acidic catalysts to directly transform cellulose into 5-hydroxymethylfurfural (5-HMF). The characteristic and morphology of the polymers were examined by Fourier transformed infrared spectroscopy, X-ray diffraction, vibrating sample magnetometer, field-emission scanning microscope, and transmission electron microscopy. The yield of 5-HMF can reach as high as 98% from the dehydration of glucose using CrCl 3 ·6H 2 O catalyst in tetrabutylammonium chloride at 120°C for 90 min. Cellulose conversion using the prepared VS-DVB in 1-butyl-3-methyl imidazolium chloride at 120°C for 180 min showed high yields of 50% glucose and 10% 5-HMF. An enhancement in 5-HMF yield was observed as reaction time increased. A combination of VS-DVB/CoFe 2 O 4 and CrCl 3 ·6H 2 O in ionic liquids was employed at optimal conditions for cellulose conversion. Magnetic catalysts were readily separated from resulting products in the magnetic field, as well as recycled and reused with negligible loss in activity. Glucose and 5-HMF yields were determined through high-performance liquid chromatography analysis.

Catalytic Transformation of Lignocellulose into Chemicals and Fuel Products in Ionic Liquids

“…Another attractive route for the transformation of cellulose into HMF is using heterogeneous acidic catalysts in ILs. − In this aspect, Zhang et al synthesized two acid-chromic chloride bifunctionalized catalysts (i.e., ATP-SO 3 H-Cr­(III) and HNTs-SO 3 H-Cr­(III)) by grafting −SO 3 H and Cr­(III) onto the surface of treated attapulgite (ATP) and halloysite nanotubes (HNTs) . These two bifunctional catalysts could catalyze the one-pot conversion of cellulose to HMF in [EMIM]­Cl, and under optimized conditions, the yield of HMF up to 31.20% and 41.22% was obtained over ATP-SO 3 H-Cr­(III) and HNTs-SO 3 H–Cr­(III), respectively.…”

Catalytic Advances in the Production and Application of Biomass-Derived 2,5-Dihydroxymethylfuran

“…At present, most chemicals and fuels in the world are directly or indirectly produced from nonrenewable fossil resources. − However, as the depletion of fossil resources continues, exploring appropriate renewable resources has become increasingly urgent and necessary. − As the only carbon-based renewable resource in the nature, biomass, possessing many excellent merits such as abundance, diversity, pervasiveness, and low cost, is considered to be an optimal and inexhaustible feedstock for the sustainable production of chemicals and fuels. − To make good use of biomass, biorefining is a very momentous approach. − During the biorefining process, 5-hydroxymethylfurfural (HMF), which is obtained by the dehydration of biomass-derived carbohydrates such as fructose, − glucose, − sucrose, − cellobiose, − inulin, − starch, − and cellulose, − is hailed as one of the most important fundamental compounds − because it can be used to synthesize many high-value products via various reactions (Figure ). For instance, the selective hydrogenation of HMF can generate 2,5-dihydroxymethylfuran (DHMF), − 2,5-dihydroxymethyltetrahydrofuran (DHMTHF),…”