STUDY OF FAUJASITE-TYPE ZEOLITE MODIFIED WITH LA AND NH41+

The acidity of faujasite zeolite was modified through ion exchange, it is treated in the present study, the Na1+ cation, part of the initial structure of faujasite, was removed by cations such as NH41+ and La3+. The obtained molar ratio of the precursor oxides for the formulation of the seed gel was: SiO2/Al2O3 = 12.26; Na2O/Al2O3 = 13.27 and Na2O/SiO2 = 2.16. In the case of the structural gel, the following molar ratios were reported: SiO2/Al2O3 = 10.90; Na2O/Al2O3 = 11.92 and Na2O/SiO2 = 2.18. The optimum crystallization temperature was 90 °C for the seed gel and 80 °C for the structural gel. The zeolite obtained was characterized by X-ray diffraction (XRD), through comparative analysis between the diffractograms of the zeolite developed and NaY-type faujasite patterns. By means of BET surface area analysis, a specific surface area of 875 m2.g-1 and a pore radius of 5.88 Å were determined, and the morphological analysis was complemented by scanning electron microscopy (SEM). The ion exchange behavior for the case of ammonium ion, reported an exchange of 59.8 mg.g-1 under the best experimental conditions (8 h, 20 cm3.g-1), while in the case of lanthanum ion it was 38 mg.g-1 (24 h, 50 cm3.g-1).