The pHzpc (pH at the zero point of charge) of a series of seven silica-alumina oxide supports, previously heat treated to 500°C, were determined by potentiometric titrations. Rigorous experimental procedures in support preparation and standardization have allowed us to compare the pHzpc of each of the oxides with the weight fraction of the pure components. The pHzpc of this homologous series varied linearly with the weight fraction of the pure components. These results are in direct agreement with a mass weighting model suggested by G. A. Parks (Advances in Chemical Series 67, ACS, Washington, D. C.) for calculating the pHzpc for any composition of a mixed oxide system.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Surfaces, Coatings and Films
- Colloid and Surface Chemistry