ZrO2-SO4 (SZ) powders were prepared by calcining at 740, 820, and 900 K hydrous precursors, obtained by a hydrothermal precipitation route from ZrCl4 solutions at 334 K, and subsequently sulfated with H2SO4 (1 M). The samples were characterised as to phase composition (XRD, Raman spectroscopy), surface area (BET) and total sulfur content. Surface functionalities and acidity features were investigated by FTIR spectroscopy of the powders themselves and of probe molecules (carbon monoxide, pyridine) adsorbed thereon. By a revised Hammett-Bertolacini technique, both the density and strength of the (protonic) surface sites were obtained. XPS analyses of the samples were performed by elaboration of the sulfur 2p, oxygen 1s and zirconium 3d spectral regions. Catalytic tests were performed both in the gas phase, for the isomerisation of n-butane at 423 and 523 K, and in liquid media, for the esterification of benzoic acid to methylbenzoate. Correlations were obtained with the samples' calcination temperature, catalytic activity, distribution of Lewis/Brønsted acid sites, and spectral features of the XPS Zr 3d doublet.

Surface features and catalytic activity of sulfated zirconia catalysts from hydrothermal precursors / C. Morterra, G. Cerrato, S. Ardizzone, C.L. Bianchi, M. Signoretto, F. Pinna. - In: PHYSICAL CHEMISTRY CHEMICAL PHYSICS. - ISSN 1463-9076. - 4:13(2002), pp. 3136-3145.

Surface features and catalytic activity of sulfated zirconia catalysts from hydrothermal precursors

S. Ardizzone;C.L. Bianchi;
2002

Abstract

ZrO2-SO4 (SZ) powders were prepared by calcining at 740, 820, and 900 K hydrous precursors, obtained by a hydrothermal precipitation route from ZrCl4 solutions at 334 K, and subsequently sulfated with H2SO4 (1 M). The samples were characterised as to phase composition (XRD, Raman spectroscopy), surface area (BET) and total sulfur content. Surface functionalities and acidity features were investigated by FTIR spectroscopy of the powders themselves and of probe molecules (carbon monoxide, pyridine) adsorbed thereon. By a revised Hammett-Bertolacini technique, both the density and strength of the (protonic) surface sites were obtained. XPS analyses of the samples were performed by elaboration of the sulfur 2p, oxygen 1s and zirconium 3d spectral regions. Catalytic tests were performed both in the gas phase, for the isomerisation of n-butane at 423 and 523 K, and in liquid media, for the esterification of benzoic acid to methylbenzoate. Correlations were obtained with the samples' calcination temperature, catalytic activity, distribution of Lewis/Brønsted acid sites, and spectral features of the XPS Zr 3d doublet.
benzoic acid ; benzoic acid derivative ; butane ; carbon monoxide ; oxygen ; proton ; pyridine ; sulfur ; sulfuric acid ; zirconium ; zirconium derivative ; zirconium oxide, acidity ; adsorption ; article ; catalysis ; catalyst ; chemical composition ; density ; gas ; infrared spectroscopy ; ionic strength ; isomerism ; liquid culture ; powder ; precipitation ; precursor; Raman spectrometry ; sulfation ; surface property ; temperature dependence ; X ray powder diffraction
Settore CHIM/02 - Chimica Fisica
Article (author)
File in questo prodotto:
Non ci sono file associati a questo prodotto.
Pubblicazioni consigliate

Caricamento pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2434/182546
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 43
  • ???jsp.display-item.citation.isi??? 41
social impact