Analytical method for the determination of intra- and extraframework gallium species in zeolite catalyst

Abstract

The aim of this work is to report a very simple analytical method for the quantitative determination of intra- and extralattice gallium species in zeolitic material using flame atomic absorption spectroscopy. The method was developed by adjusting the sample treatment severity. Whereas a HF treatment of the zeolite sample provides the total concentration of gallium, a controlled digestion with HCl allows one to detect only the nonframework species of this element. Furthermore, the HCl digestion does not modify the zeolite structure. The application of this digestion scheme to different zeolitic support with gallium in framework and nonframework position produced results that were in good aggreement with the values expected from the synthesis and preparation of these materials.