Functionalization of zeolites by transition metal for application in
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Functionalization of zeolites by transition metal for application in
Functionalization of zeolites by transition metal for application in environmental catalysis Stanisław Dzwigaj Sorbonne Universités, UPMC Univ Paris 06, UMR 7197, Laboratoire de Réactivité de Surface, F-75005, Paris, France CNRS, UMR 7197, Laboratoire de Réactivité de Surface, F-75005, Paris, France The metal ions well dispersed at zeolite framework are considered to be active sites of catalytic processes. Therefore, the incorporation of these metals into the microporous materials as isolated tetrahedral sites appears to be the important task. We have shown [1,2] that the incorporation of transition metal ions into vacant T-atom sites of framework BEA zeolite is strongly favored when, in the first step, BEA is dealuminated by treatment with nitric acid solution and then, in the second step, the incorporation of transition metal ions results in the reaction between the cationic metal species of the precursor solution and the SiO-H groups of vacant T-atom sites created by dealumination of BEA zeolite. The aim of the present work is to functionalize BEA zeolite with suitable transition metal ions (Fe3+, Co2+, Ni2+, V5+, Ag+) and to confer them specific catalytic properties related to environmentrelated issues. To obtain Fe-, Co-, Ni-, V- or Ag-zeolite catalysts the aqueous solution of Fe(NO3)3, Co(NO3)2, Ni(NO3)2, NH4VO3 or AgNO3 were used as the precursor. The series of FexSiBEA, CoxSiBEA, NixSiBEA, VxSiBEA and AgxSiBEA zeolites (x = 0.2 - 9 wt. %) were prepared and characterized by different physical techniques both at the macroscopic level (chemical analysis, XRD, BET, thermal methods (TPR, TPO, TPD), TPR, TEM) and molecular level (FT-IR, NMR, diffuse reflectance UV-Vis, XPS, XAFS, Mössbauer). The catalytic properties of these series of zeolite catalysts were investigated in the environment-related reactions: SCR of NO with ammonia and alcohols [3,4,5], N2O decomposition [4], dehydrochlorination of chloroorganic compounds [6] and partial oxidation of methane [7]. The results show that these reactions proceed efficiently on mononuclear metal species well dispersed in the structure of SiBEA zeolite. References [1] S. Dzwigaj, M.J. Peltre, P. Massiani, A. Davidson, M. Che, T. Sen, S. Sivasanker, Chem. Commun. (1998) 87. [2] S. Dzwigaj, P. Massiani, A. Davidson, M. Che, J. Mol. Catal. 155 (2000) 169. [3] J. Janas, W. Rojek, T. Shishido, S. Dzwigaj, Appl. Catal. B 123-124 ( 2012) 134. [4] P. Boron, L. Chmielarz, J. Gurgul, K. Latka, T. Shishido, J-M. Krafft, S. Dzwigaj, Appl. Catal. B 138-139 (2013) 434. [5] S. Dzwigaj, Y. Millot, J-M. Krafft, N. Popovych, P. Kyriienko, J. Phys. Chem. C 117 (2013) 12552. [6] R. Baran, I.I. Kaminska, A. Srebowata, S. Dzwigaj, Micropor. Mesopor. Mater. 169 (2013) 120. [7] K.A. Chalupka, W.K. Jozwiak, J. Rynkowski, W. Maniukiewicz, S. Casale, S. Dzwigaj, Appl. Catal. B, In Press 1