斎藤瑞季君、相原健司君が中心となって行った担持WO3触媒の酸性質に対する担体の効果に関する研究成果がCatalysis Today誌 (Elsevier)にAcceptされました。Our paper reporting the generation mechanism of acid sites over supported WO3 catalysts was accepted in Catalysis Today (Elsevier).

The effect of alumina-based supports (Al₂O₃, Al₂O₃-TiO₂, Al₂O₃-ZrO₂, SiO₂-Al₂O₃, and SiO₂) on the structure and acid properties of supported tungsten oxide catalysts was investigated. Among the tested supported tungsten oxide catalysts, WO₃/Al₂O₃-TiO₂ (Al₂O₃/TiO₂ = 9, Al-Ti9) showed the highest activity for reactions catalyzed by Brønsted acid sites and the largest Brønsted acidity. Structural characterization revealed that Brønsted acid sites on WO₃/Al-Ti9 were generated at the boundaries between domains of amorphous monolayer WO₃ and Al₂O₃-TiO₂ support and WO₃/Al₂O₃ reported previously, and that Al₂O₃ and Al-Ti9 with a high density of Lewis acid and surface hydroxyl groups resulted in the formation of Brønsted acid sites. Crystalline WO₃ species formed mainly on SiO₂-Al₂O₃ and SiO₂ with a low density of Lewis acid sites and a high density of surface hydroxyl groups. These results suggested that a high density of Lewis acid sites and surface hydroxyl groups are important factors to form amorphous WO₃ monolayer domains and to generate Brønsted acid sites on alumina-based supports.