Abstract

ALEJANDRO, Pérez; MOLINA, Rafael  and  MORENO, Sonia. EVALUATION OF SOME VARIABLES IN THE PILLARED CLAYS SYNTHESIS AND THEIR IMPACT ON THE PHENOL OXIDATION IN DILUTE AQUEOUS. Rev.Colomb.Quim. [online]. 2011, vol.40, n.3, pp.321-336. ISSN 0120-2804.

Different variables in synthesis were evaluated in the modification of two pillared smectite clays with mixed solutions of Al-Fe-Ce. The effect of ultrasound during the intercalation of pillaring species, the clay type, and the iron oxides removal of natural mineral were analyzed to obtain active materials in the phenol oxidation in aqueous diluted with a good selectivity to CO₂ through moderate experimental conditions (temperature 298K and atmospheric pressure). The solids were characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF), hydrogen temperature programmed reduction (TPR-H₂), and scanning electron microscopy (SEM), showing a successful structural change in all materials. The use of ultrasound allows modifying solids considerably in less time (20 min) than the traditional process (24 hours) maintaining the physicochemical and catalytic properties of the materials. Likewise, evidence of effect of the nature of the starting clay on the chemical and catalytic properties of the material, as well as an improvement by removing iron oxides of natural materials, achieving solids with best catalytic activity.

Keywords : Pillared clay; ultrasound; oxidation of phenol; AlFeCe; iron removal.