Morphology and activity of zirconia-sulfate aerogels

• Autorzy: Mrowiec-Białoń J. , Pająk L. , Marczewski M. , Lachowski A. , Jarzębski A.
• Języki publikacji: EN

Abstrakty

EN

Zirconia-sulfate aerogels obtained from the process with the molar hydrolysis ratio r=4 are more porous and active than those synthesized with r=2. Sulfate ions markedly hinder sintering of zirconia and structure consolidation during heat treatment and this process depends on their concentration. At a higher sulfate load (20 mol% of SO2-4 in Zro2) zirconia is amorphous upon calcinations at 773 K, irrespective of the water content in the synthesis, while at a lower load it can be crystalline. XRD analysis indicates that the crystalline phase of calcined zirconia-sulfate is cubic and not tetragonal, as observed in conventional zirconia, and reported in previous studies. Acid strength of ZrO2- SO2-4 system appears comparable to that of AlCl3/Al2O3, but lower than that of SbF5/Al2O3.

Słowa kluczowe

EN

superacids; aerogels; zirconia; catalysis

• Wydawca: Polskie Towarzystwo Chemiczne
• Czasopismo: Polish Journal of Chemistry
• Rocznik: 1999
• Tom: vol. 73 nr 5
• Strony: 805--811

Twórcy

autor

Mrowiec-Białoń J.

autor

Pająk L.

autor

Marczewski M.

autor

Lachowski A.

autor

Jarzębski A.

• Instytut Inżynierii Chemicznej PAN ul. Bałtycka 5 44-100 Gliwice