Dehydration of fructose is a way to produce an important platform chemical such as 5‐hydroxymethylfurfural (HMF) which is widely used to synthesize variety of renewable chemicals and fuel. Heteropoly acid, H3PW12O40 is highly soluble strong acidic catalyst with well‐defined structure. This study reports the modification of soluble heteropoly acid to insoluble and reusable heteropolyacid (HxZr3‐xPW12O40 ) by exchanging with Zr and investigation of its catalytic performance in selective transformation of renewable fructose to 5‐HMF in Dimethyl sulfoxide (DMSO) system. The physico‐chemical properties of HxZr3‐xPW12O40were derived from Powder‐XRD, NH3‐TPAD and FT‐IR technique. The characterization of HxZr3‐xPW12O40 revealed that the Keggin structure of HPA remained intact as proton replaced by Zr. The partial exchange of Zr in H2Zr1PW12O40 catalyst resulted in an increase in acidity, however further increase of Zr above 1, acidity was found to be decreased. At optimized reaction condition, 5‐HMF yield of 85% with 100% selectivity was achieved with H1Zr2 PW12O40 catalyst at much lower reaction time of 10 min than reported. The catalyst was observed to be recoverable, reusable as compared to parent H3PW12O40.

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Ethyl levulinate (EL) has found wide applications as chemicals and biofuel additives. Efficient catalytic conversion of abundantly available glucose to ELs over solid acid catalyst having optimum Brønsted (B) and Lewis (L) acidity is highly appreciated. Present work demonstrated, direct one‐step synthesis of EL from glucose over synergized Brønsted (H2Zr1PW12O40) and Lewis (Sn‐Beta) acid catalyst. H2Zr1PW12O40 is prepared by exchanging H+ of tungstophosphoric acid (H3PW12O40‐heteropolyacid) with Zr, improves the heterogeneity in polar medium by 50%. The combination of a physical mixture of H2Zr1PW12O40 + Sn‐Beta with 80:20 weight ratio was found to be optimum for the maximum EL yield formation of 54% from glucose at 180°C for 3 h, which is probably the highest than reported over the heterogeneous catalyst in ethanol medium. An optimal combination of B and L catalyst and its ratio is found to be crucial for the direct transformation of glucose to EL in one step. The present study also explored that this combined physical mixture of H2Zr1PW12O40 + Sn‐Beta can tolerate glucose concentration up to 30 g/L, which is probably the higher than reported. © 2019 American Institute of Chemical Engineers Environ Prog, 38:e13146, 2019

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