Direct Conversion of Glucose to 5-Hydroxymethylfurfural over H_3PW_12O_40/TEOS Heterogeneous Catalyst

5-hydroxymethylfurfural (5-hmf) is a valuable bio-based intermediate designed from carbohydrate resources such as glucose (hexose) or fructose. in this work, direct conversion of glucose into 5-hmf was studied by analysing the activity of solid acid catalyst namely silica-supported phosphotungstic acid (h_3pw_12o_40/teos) as a heterogeneous catalyst. the reactions were conducted in a three-neck conical flask using dimethyl sulfoxide (dmso) as reaction solvent under different reaction time (1, 3 and 5 hours) and temperature (100, 115 and 130°c). the effect of phosphotungstic acid loading was also studied in this literature (5, 12.5 and 20% h_3pw_12o_40). thus, this paper aims to study the optimum reaction time, temperature and h_3pw_12o_40 loading to give the maximum yield of 5-hmf via direct catalytic dehydration process. the prepared catalyst 20% h_3pw_12o_40/teos shows promising results by displaying a yield of 5-hmf as high as 62% after 3 hours at 130°c reaction temperature in the presence of dmso solvent. since heteropoly acid is highly soluble in dmso, thus h_3pw_12o_40 supported in teos (h_3pw_12o_40/teos) is a promising solid catalyst for the conversion of glucose into 5-hmf. the prepared catalyst can also be recovered and recycled easily without significant loss of performance.