A theorethical-experimental study on acidity of molybdovanadophosphate heteropolyanions with Keggin structure

P. VILLABRILLE; J. SAMBETH; P. VÁZQUEZ

Cancun, México

Otro; 18th North American Catalysis Society Meeting; 2003

Sociedad Norteamericana de Catálisis

Heteropoly catalysts are promising green catalysts since most of them are environmentally friendly. The free acids with Keggin structure are less stable than the salified materials but can be obtained in structurally much better defined samples. Theoretically, when Mo atoms of H3PMo12O40 (MPA) are partly substituted by V atoms, its acid strength is reduced together with its thermal stability. In this work, the molybdovanadophosphate heteropolyanions (HPVA) with Keggin primary structure are studied from theorethical point of view to determine the effect of vanadium substitution with semi-empirical Extended Hückel Method. In addition, their acidic properties are characterized by potentiometric titration with n-butylamine.