Synthesis, characterization and study of the reaction nature of the beundantite
Abstract
In this work is shown a study on the synthesis, characterization and study of the nature of decomposition of the beudantite. The synthesis was carried out using the maximum dissolution technique, at a temperature of 94 °C, variation of pH and mechanical stirring. The solids so obtained were characterized by scanning electron microscopy in conjunction of energy disperssive spectrometry of X rays (SEM-EDS), X ray diffraction (XRD), inductively coupled plasma spectrometry (ICP), atomic absorption spectrometry (AAS), gravimetry and dicromatography. The obtained product shows a tendency to spheroid morphology, with particle sizes majority of 25 microns, constituted by rombohedral crystals interconnected each one in a relatively compact texture. The above characteristics are favorable to execute the study of the nature of reaction. According with the obtained results, it could be observed that the decomposition of the beudantite consist of three periods; an induction period (without apparent changes), the proggressive conversion period (where there is a diffusion of the ions and to the solution), and finally a stabilization period, which indicates the end of the reaction. The curves obtained are of the type "S" and the treatment of the results fit favorably to the decreasing core model and chemical control.
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References
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