title: Effects of metal and acidic sites on the reaction by-products of butyl acetate oxidation over palladium-based catalysts.
abstract: Catalytic oxidation is widely used in pollution control technology to remove volatile organic compounds. In this study, Pd/ZSM-5 catalysts with different Pd contents and acidic sites were prepared via the impregnation method. All the catalysts were characterized by means of N2 adsorption-desorption, X-ray fluorescence (XRF), H2 temperature programmed reduction (H2-TPR), and NH3 temperature programmed desorption (NH3-TPD). Their catalytic performance was investigated in the oxidation of butyl acetate experiments. The by-products of the reaction were collected in thermal desorption tubes and identified by gas chromatography/mass spectrometry. It was found that the increase of Pd content slightly changed the catalytic activity of butyl acetate oxidation according to the yield of CO2 achieved at 90%, but decreased the cracking by-products, whereas the enhancement of strong acidity over Pd-based catalysts enriched the by-product species. The butyl acetate oxidation process involves a series of reaction steps including protolysis, dehydrogenation, dehydration, cracking, and isomerization. Generally, butyl acetate was cracked to acetic acid and 2-methylpropene and the latter was an intermediate of the other by-products, and the oxidation routes of typical by-products were proposed. Trace amounts of 3-methylpentane, hexane, 2-methylpentane, pentane, and 2-methylbutane originated from isomerization and protolysis reactions.
authors: Department of Environmental Nano-materials, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
authors: Lin
authors: L
authors: Yue
authors: Department of Environmental Nano-materials, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
authors: Chi
authors: C
authors: He
authors: Department of Environmental Nano-materials, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
authors: Zhengping
authors: Z
authors: Hao
authors: The Administrative Center for China's Agenda 21, Beijing 100038, China.
authors: Shunbing
authors: S
authors: Wang
authors: National Urban Environmental Pollution Control Engineering Techniques Research Center, Beijing Municipal Research Institute of Environmental Protection, Beijing 100037, China. Electronic address: wanghailin@cee.cn.
authors: Hailin
authors: H
authors: Wang
mesh_terms: D000085:Acetates / Q000737:chemistry*; D000397:Air Pollution / Q000517:prevention & control; D008401:Gas Chromatography-Mass Spectrometry; D008670:Metals / Q000737:chemistry; D010084:Oxidation-Reduction; D010165:Palladium / Q000737:chemistry*
chemical_list: D000085:Acetates; D008670:Metals; C006848:butyl acetate; D010165:Palladium
keywords: Pd/ZSM-5; VOCs; butyl acetate; catalytic oxidation; reaction by-product