Eco‐Friendly Production of 5‐Hydroxymethylfurfural from Sucrose Using Commercially Available Dihydric Phosphate as a Catalyst

An eco‐friendly catalytic system consisted of dihydric phosphate (H2PO4—) catalyst and a methyl isobutyl ketone (MIBK)/H2O biphasic solvent has been constructed to produce 5‐hydroxymethylfurfural (HMF) from sucrose, a cheaper and more widely available feedstock than fructose. The effects of reaction conditions, viz., catalyst dosage, reaction temperature, and reaction time, on this dehydration reaction have been investigated systematically, affording more than 70% of HMF yield under the optimum conditions. This environmentally friendly system is also broadly substrate‐tolerant, high concentration of sucrose (86%), scalable catalytic system (scaled up 10 times), and sugarcane juice also give 62.5%, 70.1%, and 70.7% of HMF yield, respectively. Moreover, the function of H2PO4— containing system for isomerization of glucose into fructose has been confirmed; and the dehydration reaction has been proposed to proceed through the catalytic hydrolysis of sucrose into glucose and fructose by protons (H+), followed by the isomerization of glucose into fructose by hydrogen phosphate ions (HPO42−), and the dehydration of fructose into HMF by protons (H+), which are all from the dissociation of H2PO4— ions. Readily available and eco‐friendly catalyst, abundantly available feedstock, and simple reaction conditions could mark this process promising for HMF production in industry. Tri‐functional dihydric phosphate: The dihydric phosphate (H2PO4—) could act as an eco‐friendly tri‐functional catalyst for production of 5‐hydroxymethylfurfural (HMF) from sucrose through the catalytic hydrolysis of sucrose into glucose and fructose (H+ ions), isomerization of glucose into fructose (HPO42− ions), and subsequent dehydration of fructose into HMF (H+ ions).