In the present work a study regarding the iron removal process from a yellow kaolin of industrial interest by oxalic and sulphuric acid leaching has been carried out. A complete chemical and mineralogical characterisation has been performed by XRD, XRF, IR and SEM: this study permitted to establish that the iron present in the ore is contained in the finer fractions, consisting especially of minerals such as illitemontmorillonite and vermiculite, whereas kaolin doesn's contain iron in its structure, except in very small amounts. Leaching tests were then performed to exaluate the effect of the gas purging (N_2 or air) during the leaching and to check the effect of the pH and oxalic acid concentration in a wide range of experimental conditions. The experimental results showed the technical feasibility of the process in the beneficiation of industrial minerals such as kaolin's.
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