Solid acid catalysts based on supported tungsten oxides
نویسندگان
چکیده
Supported WOx clusters are active and stable catalysts for isomerization, dehydration, and cracking reactions. Brønsted acid sites form on WOx clusters when a lower valent element replaces W6+ or when W6+ centers reduce slightly during catalytic reactions. WOx clusters of intermediate size provide the balance between reducibility and accessibility required to maximize the number of surface H+ species in WOx–ZrO2, zirconium tungstate, and oxygen-modified WC catalysts. H2 is involved in the generation and maintenance of Brønsted acid sites during catalytic reactions on WOx clusters.
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