Optimization of the operative conditions for heteropolyacids synthesis through ion exchange

Phospho-tungstic and phospho-molybdic Wells-Dawson heteropolyacids, H<SUB>6</SUB>P<SUB>2</SUB>W<SUB>18</SUB>O<SUB>62</SUB>.xH<SUB>2</SUB>O and H<SUB>6</SUB>P<SUB>2</SUB>Mo<SUB>18</SUB>O<SUB>62</S...

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Detalles Bibliográficos
Autores: Matkovic, Silvana R., Valle, Graciela M., Briand, Laura Estefanía
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2005
País:Argentina
Institución:Universidad Nacional de La Plata
Repositorio:SEDICI (UNLP)
Idioma:inglés
OAI Identifier:oai:sedici.unlp.edu.ar:10915/36938
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/36938
Access Level:acceso abierto
Palabra clave:Ciencias Exactas
Química
Heteropolyacid
ammonium compounds
ion exchange
HPA
POM
optimization
Wells-Dawson
phosphorus compounds
solutions
synthesis
organic acids
Descripción
Sumario:Phospho-tungstic and phospho-molybdic Wells-Dawson heteropolyacids, H<SUB>6</SUB>P<SUB>2</SUB>W<SUB>18</SUB>O<SUB>62</SUB>.xH<SUB>2</SUB>O and H<SUB>6</SUB>P<SUB>2</SUB>Mo<SUB>18</SUB>O<SUB>62</SUB>.xH<SUB>2</SUB>O respectively, were synthesized through ion exchange with a higher yield (∼ 90%) than the conventional organic route (∼ 70%). Pure, non-degraded heteropolyacids are obtained when the corresponding ammonium salt [(NH<SUB>4</SUB>)<SUB> 6</SUB>P<SUB>2</SUB>W<SUB>18</SUB>O<SUB>62</SUB>.13H<SUB>2</SUB>O or (NH<SUB>4</SUB>)<SUB>6</SUB>P<SUB>2</SUB>Mo<SUB>18</SUB>O<SUB>62</SUB>.12H<SUB>2</SUB>O] is kept in contact with an acid resin [about (1:0.8) salt:resin weight ratio] up to three days. The use of an organic media instead of an aqueous media greatly favors the completeness of the exchange.