Separation of Oxygen and Nitrogen by Porous Cyanometallates

The adsorption-based separation in porous solids takes place through steric, kinetic, or equilibrium effect selectivity. In this contribution the oxygen-nitrogen separation by four porous frameworks representative of cyanometallates was studied by inverse gas chromatography. The following materials...

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Detalles Bibliográficos
Autores: ZAMORA, B., AUTIE, M., CONTRERAS, J.L., CENTENO, M., REGUERA, E.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2009
País:México
Institución:Instituto Politécnico Nacional
Repositorio:Repositorio Digital del IPN
OAI Identifier:oai:www.repositoriodigital.ipn.mx:123456789/10921
Acceso en línea:http://hdl.handle.net/123456789/432
http://www.repositoriodigital.ipn.mx/handle/123456789/10921
Access Level:acceso abierto
Palabra clave:adsorption
air separation
porous solids
prussian blue analogue
Descripción
Sumario:The adsorption-based separation in porous solids takes place through steric, kinetic, or equilibrium effect selectivity. In this contribution the oxygen-nitrogen separation by four porous frameworks representative of cyanometallates was studied by inverse gas chromatography. The following materials were considered: Cd3[Co(CN)6]2 (cubic), Zn3[Co(CN)6]2 (rhombohedral), Zn3K2 [Fe(CN)6]2 (rhombohedral) and Co[Fe(CN)5NO] (cubic). Chromatographic separation profiles from gases mixtures using columns of these materials were recorded. For columns prepared from rhombohedral zinc hexacyanocolbaltate(III) excellent separation of O2 and N2 was observed. Such behavior was attributed to a kinetic-based selectivity related to the size and shape for the pore windows of this material. The porous framework of this zinc phase is formed by ellipsoidal cavities (12.5 9 8A˚ ) communicated by elliptical windows of 5A˚ . For Cd3[Co(CN)6]2 and Co[Fe(CN)5 NO] also kinetic-based selectivity was observed while for Zn3K2[Fe(CN)6]2 the Kþ ion located close to the cavity windows hinders the porous windows accessibility for nitrogen and oxygen molecules. All the samples to be studied were characterized from X-ray diffraction, infrared spectroscopy, termogravimetric and adsorption data.