CARACTERIZACIÓN DE CATALIZADORES BÁSICOS TIPO HIDROTALCITA SINTETIZADOS POR IRRADIACIÓN DE MICROONDAS CHARACTERIZATION OF BASIC CATALYSTS OF THE TYPE HYDROTALCITE SYNTHESIZED BY MICROWAVE IRRADIATION

Hydrotalcites are microporous materials with a lamellar structure and anionic exchange properties. They can be used in many applications depending on cristallinity, composition, thermal stability and other physicochemical properties. Due to the importance of these materials, many studies developing new synthesis techniques have been proposed, among them, the synthesis by microwave irradiation has many advantages, mainly due to the reduction of reaction time. In this work the synthesis of basic hydrotalcite-like compounds with a Mg/Al composition and with molar ratios Mg/Al of 2:1, 3:1 and 4:1, is presented. The synthesis gels were treated hydrothermically in a microwave reactor operating at 200 W, at a temperature of 80°C and at atmosphere pressure. In addition, some samples were synthesized with a Mg/Al molar ratio of 3 with different irradiation power (400 and 600 W) to determine the power effect on the structural and morphological features. The samples were characterized by X-ray diffraction, infrared spectroscopy, scanning electron microscopy and nitrogen adsorption (BET area). It was found that purity, specific surface area and crystallinity depend on the Mg/Al molar ratio. Furthermore, thermal stability increases with irradiation power as the specific surface area.