Solid P-W Keggin Heteropoly Compounds as Effective Catalysts for the Sorption-Decomposition of NO_X

Abstract:

Several new heteropoly compounds catalysts with pronounced activities in NO_x conversion via adsorption-decomposition process in a fixed-bed reactor were evaluated concerning the principal internal and external factors having marked effects on the process of adsorption. Results showed that substitution of H⁺ in HPW (H₃PW₁₂O₄₀•6H₂O) by NH₄⁺ results in marked enhancement of the catalyst activity, however, substitution of coordination atom W in the [PW₁₂O₄₀]^3- anion by one or more Mo atoms tends to lower the catalyst activity and such tendency deepens with the increase in the Mo atom numbers introduced. It is for the first time that the nano-effect was observed with nano (NH₄)₃PW₁₂O₄₀ catalyst, in which a 1.6% to 10.6% enhancement in NO_x adsorption efficiency was obtained in comparison with the same catalyst in normal particle size. By IR analysis, NO was found to be adsorbed via interaction with the proton of HPW structure. With the aid of GC-MS analysis, the process effectiveness for NO_x decomposition into N₂ was confirmed.

• Periodical: Advanced Materials Research (Volumes 233-235)
• Pages: 355-358
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.233-235.355
• Online since: May 2011
• Authors: Rui Wang, Tao Ma, Dan Wu, Vladimir N. Korchak
• Keywords: Adsorption, Catalyst, Decomposition, Denitrification

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