Synthesis of 5‐hydroxymethylfurfural from fructose and inulin catalyzed by magnetically‐recoverable Fe3O4@SiO2@TiO2–HPW nanoparticles

Abstract

AbstractBACKGROUND5‐Hydroxymethylfurfural (HMF) is an important platform chemical that can be generated from biomass using catalysts and used for the production of biofuels and biobased polymers.RESULTSIn this study, a novel magnetically‐recoverable catalyst (Fe3O4@SiO2@TiO2−HPW) was synthesized for the first time by immobilizing H3PW12O40 (HPW) on the surfaces of SiO2 and TiO2‐coated Fe3O4 nanoparticles. A number of techniques, including inductively coupled plasma (ICP) spectroscopy, transmission electron microscopy (TEM), Fourier‐transform infrared (FTIR) spectroscopy and nitrogen (N2) adsorption–desorption analysis, were used to characterize the catalyst. Results showed that the catalyst had a porous structure and the Keggin structure of HPW on the surface of the catalyst was well‐preserved. The catalyst was then used for the syntheses of HMF from fructose and inulin using dimethyl sulfoxide (DMSO) as a solvent, and the influences of reaction temperature and reaction time were investigated. Results showed that HMF yields obtained from fructose and inulin reached 83% and 54%, respectively. After reaction, the catalyst could be easily separated from reaction mixture using an external magnet, and the catalytic activity of the catalyst was well‐preserved after more than five reuses.CONCLUSIONThis magnetically‐recoverable catalyst is efficient not only for the syntheses of HMF from fructose and inulin, but also potentially for the one‐step production of HMF from inulin‐containing biomass, and its magnetic property may overcome the difficulty of catalyst separation from the insoluble biomass residues. © 2019 Society of Chemical Industry