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Updated: Jun 25, 2026

Temperature-programmed Deoxygenation of Acetic Acid on Molybdenum Carbide Catalysts
Published on: February 7, 2017
Characterization of silica-supported dodecatungstic heteropolyacids as a function of their dehydroxylation
Nicolas Legagneux1, Jean-Marie Basset, Amélie Thomas
1Equipe LCOMS, ESCPE Lyon, Villeurbanne, Cédex, France.
Abstract:
Dodecatungsto-silicic H(4)SiW(12)O(40) and -phosphoric acids H(3)PW(12)O(40) were deposited on silica by a classical impregnation technique. The resulting materials were studied by in situ Raman and infrared spectroscopy, XPS and by solid-state (1)H MAS NMR as a function of their dehydroxylation temperature. The data show that in the case of H(3)PW(12)O(40) three silanol groups are protonated while in the case of H(4)SiW(12)O(40) at least one acidic proton remains. Upon heating this proton reacts leading to a disordered structure and a broadening of the W-O Raman bands.
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