Titanium Phosphate Grafted on Mesoporous SBA-15 Silica as a Solid Acid Catalyst for the Synthesis of 5-Hydroxymethylfurfural from Glucose

The grafting of titania on SBA-15 followed by its phosphation was presented to prepare a mesoporous Lewis–Brønsted bifunctional solid acid catalyst for the tandem conversion glucose via fructose 5-hydroxymethylfurfural (HMF). Titania dispersed as an amorphous surface layer containing abundant coordinatively unsaturated tetrahedral Ti ions, which reactive and readily transformed upon into new titanium phosphate phase with chemical formula identified Ti2O3(H2PO4)2·2H2O. ordered structure well maintained after three modification cycles, affording desirable area over 300 m2/g. SBA-15-supported affords higher overall acidity Brønsted Lewis ratio, compared conventional post-phosphated bulk anatase titania. ions adjacent protonated groups could form pairs at molecular level proximity, largely enhanced selective catalysis HMF. An optimized HMF yield 71% achieved 160 °C in water–methyltetrahydrofuran biphasic system catalyst. exhibited good hydrothermal stability rather limited silicon leaching, no distinct pore collapse or performance loss sequential reaction runs.