INVESTIGADORES
BRIAND Laura Estefania
artículos
Título:
Environmentally Friendly Synthesis of Wells-Dawson Heteropolyacids. Active Acid Sites Investigation Thorugh TPSR of Isopropanol
Autor/es:
SILVANA R. MATKOVIC; GRACIELA VALLE; LUIS A. GAMBARO; LAURA E. BRIAND
Revista:
CATALYSIS TODAY
Editorial:
Elsevier B.V.
Referencias:
Lugar: Amsterdan; Año: 2008 vol. 133 p. 192 - 199
ISSN:
0920-5861
Resumen:
Fosfo-tungstic and fosfo-molybdic Wells Dawson heteropolyacids, H6P2W18O62 and H6P2Mo18O62 respectively, were synthesized through ion-exchange. This novel method possesses a higher yield than the conventional organic route. Wells Dawson heteropolyacids are obtained when the corresponding ammonium salt is kept in contact with an acid resin [about (1:0.8) salt:resin weight ratio] up to 3 days. The use of an organic media instead of an aqueous media greatly favors the completeness of the exchange.Temperature programmed surface reaction of chemisorbed isopropoxy species towards propylene allows determined the number of active acid surface/bulk sites and the activation energy of the surface reaction. This parameter provided evidences of the influence of the central phosphorous atom and oxide supports on the acid strength of the active sites.
