STUDY OF REMOVING IMPURITIES OF KAOLIN CLAYS FROM HIDALGO STATE, (MEXICO)

Abstract

This paper reports the study of the removal of impurities and characterization of kaolin clays from different mines in Agua Blanca de Iturbide, Hidalgo (Mexico), treated with the aim of increasing its whiteness index which were collected by selective sampling, processed by a simple method (sieving, dispersal and settlement) and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), particle size analysis (ATP), chemical analysis coupled plasma (ICP ) and whiteness index (IB). The mineral was processed by crushing, attrition and screening. Sieving of fine products were mixed vigorously with deionized water at 45 percent solids in wt.% adding 1 Kg Ton -1 of dispersant. Subsequently, the pulp was diluted and settling at 20 percent solids, with the purpose of obtaining micron particles and finally a second settling was applied. The results showed that the sieving process removed 30% of silica sand whose contents were higher compared with those contained in the fine material. Applying the process of settling suspended particles were obtained with an average size of 1,83 μm. In the crystallographic study, in addition to kaolinite, were identified different impurities such as sulfides, oxides and carbonates. By crystallographic studies, chemical analysis by ICP and the whiteness index measurement was carried out monitoring of the reduction of impurities in each separation process. Final concentrate was obtained with average particle size of 1,83 μm, a whiteness index of 91,27% and an overall weight recovery of 63%.