QUANTITATIVE-DETERMINATION OF PHILLIPSITE IN TUFFS BASED ON ITS CATION-EXCHANGE PROPERTIES

The applications of zeolite-bearing tuffs depend in a great extent on their zeolite content. A single method to determine phillipsite in ass ociation with these materials is proposed. The method is based on the determination of the cation-exchange capacity (CEC), by using 1 M NH4C l as saturating solution of the exchange sites and measuring the NH4removed by a solution of 1 M KCl. Results have been compared with thos e obtained by X-ray diffraction using the method of Chung, and also wi th those obtained by thermogravimetric analysis, according to the meth od of De'Gennaro and Colella. The results of this study show optimum c orrelation coefficients between the values of the percentage of philli psite obtained by X-ray diffraction or thermogravimetric analysis and the CEC.