The Initial Surface Structure of Co₃O₄ as a Factor of Influence on Kinetic Features of the Dissolution of the Solid Phase

Due to the depletion of natural reserves of cobalt-containing ores, it is urgent to optimize the processes of cobalt replenishment, based on the leaching of its compounds, processing of industrial waste, regeneration of cobalt compounds from catalysts. The kinetic characteristics of the dissolution of metal oxides are influenced by the initial state of their surface structure, which requires the accumulation of experimental material and individual targeted studies. The paper presents the results of an experimental study of the surface structure of industrial Co₃O₄ cobalt oxide samples. The studies were carried out by electron microscopy and X-ray phase analysis and revealed the size and shape of the Co₃O₄ particles and the nature of their surface distribution. The correspondence of experimental and theoretical data has been established, Co₃O₄ cobalt oxide has been identified as an α-form of the cubic crystal system. The data obtained are of interest in the study of the effect of the surface characteristics of the solid phase of Co₃O₄ cobalt oxide on the dissolution kinetics under the chemical and electrochemical influence

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