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Microporous Keggin-type polyoxometalate material was synthesised by supporting H3PW12O40 into a silica matrix via a sol-gel technique. The silica-supported 12-tungstophosphoric acid (H3PW12O40/SiO2) obtained is insoluble and readily separable porous materials with uniform micropores (0.57 nm) and a high specific surface area (350.5 m2/g) in oxygen-containing polar solvents. H3PW12 O40/SiO2 was characterized by infrared spectrophotometer (IR), ultraviolet-visible spectrophotometer (UV-vis), inductively coupled plasma (ICP), thermogravimetric analysis (TGA) and Brunner-Emmett-Teller method (BET) measurements. H3PW12O40/SiO2obtained catalyzed the acetal reaction between benzaldehyde and ethylene glycol to produce 2-phenyl-1, 3-dioxolane more efficiently than the typical solid acids such as SO42- /ZrO2, Nafion-H and H-ZSM-5. Conversion was 93. 8% for benzaldehyde during the reaction period of 2 h. H3PW12O40/SiO2 kept its initial activity during three times of reuse. The initial acetal reaction follows a sec
Microporous Keggin-type polyoxometalate material was synthesized by supporting H3PW12O40 into a silica matrix via a sol-gel technique. The silica-supported 12-tungstophosphoric acid (H3PW12O40 / SiO2) was insoluble and readily separable porous materials with uniform micropores (0.57 nm) H3PW12 O40 / SiO2 was characterized by infrared spectrophotometer (IR), ultraviolet-visible spectrophotometer (UV-vis), inductively coupled plasma (ICP), thermogravimetric H3PW12O40 / SiO2obtained catalyzed the acetal reaction between benzaldehyde and ethylene glycol to produce 2-phenyl-1, 3-dioxolane more efficiently than the typical solid acids such as SO42- / ZrO2, Nafion-H and H-ZSM-5. Conversion was 93. 8% for benzaldehyde during the reaction period of 2 h. H3PW12O40 / SiO2 kept its initial activity during three times of reuse. The initial acetal reac tion follows a sec