Efficient Conversion of Glucose into 5-Hydroxymethylfurfural Using a Sulfonated Carbon-Based Solid Acid Catalyst: An Experimental and Numerical Study

In this study, a sulfonated oxidized activated carbon (SO3H-OAC) catalyst was prepared through oxidation of activated carbon (OAC) followed by sulfonation and characterized by different characterization techniques such as FTIR, Pyridine-FTIR, XRD, TPD-NH3/CO2, BET, TGA, Raman, and elemental analysis. The as-synthesized SO3H-OAC catalyst bearing sulfonyl hydroxide (-SO3H), hydroxyl (-OH), and carboxyl (-COOH) functional groups with strong Bronsted base and acid sites could demonstrate an excellent bifunctional activity in conversion of glucose into 5-hydroxymethylfurfural (HMF) in a biphasic THF/H2O-NaCl solvent system (3:1 v/v), achieving almost 93% HMF yield and selectivity at 160 degrees C in 3 h. The catalyst could also show a remarkable recyclability and was used for 5 recycles without substantial loss in catalytic activity. A comprehensive mathematical model was also developed to evaluate the consecutive conversion of glucose, and respective kinetic parameters were identified by an inverse modeling technique using COMSOL Multiphysics software. Based on numerical modeling, activation energies of 54.6 and 26.6 kJ/mol were respectively achieved for glucose isomerization to fructose and consecutive fructose dehydration to HMF, signifying that fructose could convert into HMF more readily than glucose.