Synthesis of vinyl acetate on Pd-based catalysts
نویسنده
چکیده
Vinyl acetate (VA) synthesis over Pd–Au catalysts is an important industrial reaction that has been studied extensively; however, there is no consensus regarding the reaction mechanism, the active site, the key intermediates, and the role of Au. Recent results from our laboratories using a combination of surface science and kinetic methods on technical and model catalytic systems have established that the VA synthesis reaction is structure sensitive, including being dependent on the Pd–Au particle size. The role of Au is to isolate surface Pd atoms into Pd monomeric sites thereby enhancing the VA formation rate and selectivity. This paper reviews the current understanding of this reaction on Pd, Pd–Au, and Pd–Sn catalysts. # 2007 Elsevier B.V. All rights reserved.
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The formation of PdCx over Pd-based catalysts in vapor-phase vinyl acetate synthesis: does a Pd–Au alloy catalyst resist carbide formation?
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