Preparation of Al/Fe-pillared clays: effect of the starting mineral
Fecha
2017Autor
Versión
Acceso abierto / Sarbide irekia
Tipo
Artículo / Artikulua
Versión
Versión publicada / Argitaratu den bertsioa
Impacto
|
10.3390/ma10121364
Resumen
Four natural clays were modified with mixed polyoxocations of Al/Fe for evaluating
the effect of the physicochemical properties of the starting materials (chemical composition,
abundance of expandable clay phases, cationic exchange capacity and textural properties) on
final physicochemical and catalytic properties of Al/Fe-PILCs. The aluminosilicate denoted C2
exhibited the highest potential ...
[++]
Four natural clays were modified with mixed polyoxocations of Al/Fe for evaluating
the effect of the physicochemical properties of the starting materials (chemical composition,
abundance of expandable clay phases, cationic exchange capacity and textural properties) on
final physicochemical and catalytic properties of Al/Fe-PILCs. The aluminosilicate denoted C2
exhibited the highest potential as starting material in the preparation of Al/Fe-PILC catalysts,
mainly due to its starting cationic exchange capacity (192 meq/100 g) and the dioctahedral nature
of the smectite phase. These characteristics favored the intercalation of the mixed (Al13x/Fex)7+
Keggin-type polyoxocations, stabilizing a basal spacing of 17.4 Å and high increase of the BET
surface (194 m2/g), mainly represented in microporous content. According to H2-TPR analyses,
catalytic performance of the incorporated Fe in the CatalyticWet Peroxide Oxidation (CWPO) reaction
strongly depends on the level of location in mixed Al/Fe pillars. Altogether, such physicochemical
characteristics promoted high performance in CWPO catalytic degradation of methyl orange in
aqueous medium at very mild reaction temperatures (25.0 1.0 C) and pressure (76 kPa), achieving
TOC removal of 52% and 70% of azo-dye decolourization in only 75 min of reaction under very low
concentration of clay catalyst (0.05 g/L). [--]
Materias
Smectite,
Pillared clay,
Keggin-like mixed Al/Fe polyoxocation,
Mineralogical composition,
Catalytic wet peroxide oxidation
Editor
MDPI
Publicado en
Materials, 2017, 10, 1364
Departamento
Universidad Pública de Navarra. Departamento de Química Aplicada /
Nafarroako Unibertsitate Publikoa. Kimika Aplikatua Saila
Versión del editor
Entidades Financiadoras
The financial support from Proyecto Agua Potable Nariño (BPIN 2014000100020), CT&I Fund
of the SGR—Colombia is kindly acknowledged. HJM also gratefully thanks the MSc scholarship granted by
Departamento de Nariño (BPIN 2013000100092) and managed by CEIBA Foundation, Colombia. M.A.V. and A.G.
thank the support from the Spanish Ministry of Economy and Competitiveness (MINECO) and the European
Regional Development Fund (FEDER) (projects MAT2013-47811-C2-R and MAT2016-78863-C2-R). A.G. is also
grateful for financial support from Santander Bank through the Research Intensification Program.