Croatica Chemica Acta, Vol. 72 No. 2-3, 1999.
Original scientific paper
A Study of the Mn, Co and Ni Environment in the As-synthesized and Rehydrated-calcined Aluminophosphate with Chabazite-like Topology
Nevenka Rajić
; National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia
Iztok Arčon
; School of Environmental Sciences, 5001 Nova Gorica, Slovenia
Venčeslav Kaučič
; National Institute of Chemistry, Hajdrihova 19, 1000 Ljubljana, Slovenia
Alojz Kodre
; Department of Physics, Faculty of Mathematics and Physics, University of Ljubljana, 1000 Ljubljana, Slovenia
Abstract
Diffuse-reflectance spectroscopy (DRS), X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) methods are applied to an investigation of Mn, Co and Ni local environments in MnAlPO, CoAlPO, and NiAlPO materials with chabazite-like topology. For all three products, insertion of the transition metals into tetrahedral Al-sites has been found. Calcination and rehydration of the as-synthesised materials cause a change of the oxidation number and co-ordination geometry of Mn and Co, while the oxidation and co-ordination number of Ni remain unaffected.
Keywords
aluminophosphates; molecular sieves; MAPO-34; chabazite-like; EXAFS, XANES; diffuse reflectance spectroscopy
Hrčak ID:
132260
URI
Publication date:
1.9.1999.
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