Estudio estadístico de la incidencia de ciertas variables de síntesissobre la cristalinidad y otras propiedades de hidrotalcitas Ni, Fe

Abstract

This paper shows the variable incidence in the synthesis of hydrotalcites with Ni-Fe(CO3) composition related to their structural characteristics associated to synthesis methods: microwave radiation and co-precipitation by using a 24-1 fractional factorial experimental design. Properties were compared using the Fisher factor to establish the influence of variables: metallic molar ratio, pH, crystallization or radiation time, and precipitation temperature. Obtained compounds were characterized by X-ray diffraction (XRD). Cell parameters such as: average distance between cations (a), distance between brucite layers (c) and crystal size (ε) were studied. From a statistic point of view, using the co-precipitation method, the metallicmolar ratio affects the cell parameter a, and the precipitation temperature affects the c cell parameter value. Cell parameters and the crystal size were not affected by the used microwave radiation method. Therefore, the microwave radiation method is more versatile for the synthesis conditions not affecting obtained hydrotalcite characteristics. By using the variance analysis the crystal size and lattice parameters a and b, significant differences were not obtained between the co-precipitation and microwave methods.