title: Catalytic behavior and reaction routes of MEK oxidation over Pd/ZSM-5 and Pd-Ce/ZSM-5 catalysts.
abstract: Catalytic oxidation is a widely used pollution control technology for removing volatile organic compounds. Pd-Ce/ZSM-5 catalysts with different Ce contents were prepared by a co-impregnation method, and their catalytic performance was investigated for the oxidation of methyl ethyl ketone (MEK). The by-products of the reaction were monitored using gas chromatography and collected in thermal desorption tubes, which were further analyzed by gas chromatography/mass spectrometry. The PdCe(9.6)/ZSM-5 catalyst displayed the highest catalytic efficiency, as a consequence of a higher amount of strong acid sites and a superior PdO-Pd redox cycle in the presence of a CeO(2) additive. The introduction of CeO(2) enriched the by-product species. The formation mechanisms and oxidation routes of typical by-products, such as methyl acetate, 1-penten-3-one and 3-buten-2-one, 3-methyl, during MEK oxidation over Pd-Ce/ZSM-5 catalysts was also analyzed. CH(3)* species that formed on the catalyst were identified as reaction intermediaries. Trace amounts of acetic acid and methyl vinyl ketone were also detected and were further oxidized to methyl acetate, 1-penten-3-one and 3-buten-2-one, 3-methyl.
authors.affiliation: Department of Environmental Nano-materials, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, PR China.
authors.forename: Lin
authors.initials: L
authors.lastname: Yue
authors.forename: Chi
authors.initials: C
authors.lastname: He
authors.forename: Xinyan
authors.initials: X
authors.lastname: Zhang
authors.forename: Peng
authors.initials: P
authors.lastname: Li
authors.forename: Zhuo
authors.initials: Z
authors.lastname: Wang
authors.forename: Hailin
authors.initials: H
authors.lastname: Wang
authors.forename: Zhengping
authors.initials: Z
authors.lastname: Hao
mesh_terms: D000393:Air Pollutants / Q000737:chemistry*; D000397:Air Pollution / Q000517:prevention & control; D002074:Butanones / Q000737:chemistry*; D002384:Catalysis; D002563:Cerium / Q000737:chemistry*; D010084:Oxidation-Reduction; D010165:Palladium / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry; D013696:Temperature; D014961:X-Ray Diffraction; D017641:Zeolites / Q000737:chemistry*
chemical_list: D000393:Air Pollutants; D002074:Butanones; D012997:Solvents; C570564:ZSM-5 zeolite; D017641:Zeolites; D002563:Cerium; D010165:Palladium; C005222:methylethyl ketone