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 principales:	Matkovic, Silvana R., Valle, Graciela M., Briand, Laura Estefanía
Formato:	Articulo
Lenguaje:	Inglés
Publicado:	2005
Materias:	Ciencias Exactas Química Heteropolyacid ammonium compounds ion exchange HPA POM optimization Wells-Dawson phosphorus compounds solutions synthesis organic acids
Acceso en línea:	http://sedici.unlp.edu.ar/handle/10915/36938 http://www.scielo.br/pdf/mr/v8n3/26050.pdf
Aporte de:	SEDICI (UNLP) de Universidad Nacional de La Plata

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.