Mineralogical and Chemical Characteristics of Clays Consumed in the District of Abidjan (CÔte D’Ivoire)

Abstract

Clay materials of the quarry of Bingerville (district of Abidjan) have been characterized by chemical analysis, X-rays diffraction, infrared spectroscopy and thermal analysis. These materials contain kaolinite (41% - 84%), illite (4% - 10%), quartz (14% - 27%), goethite (2% - 5%) and small amount of rutile (1%) that are not toxic minerals. They also contain some heavy metals which are beneficial to human biological activity (cobalt, copper, molybdenum, zinc) in tiny quantities. Some other heavy metals (lead, cadmium) which are considered as poisonous for human are present in very low content. The samples characterized by relatively fine grains are moderately crystallized. Their specific surface area varied from 26 to 43 m 2 · g — 1 . The mineralogical and physicochemical characteristics of these samples are like ones known for their healing properties. The consumption by internal way of studied materials, although it may be beneficial, requires a sifting to remove coarse grains (Φ > 2 μm) and a previous microbiological control.