Mineralogy and Geochemistry of Residual clay Formation in Sosan Akoko, Southwestern Nigeria: Implications for Industrial Applications

Abstract

Residual clay body overlying Precambrian basement complex in Sosan Akoko, Southwestern Nigeria was studied for its mineralogical and physicochemical characteristics. The aim of the study was to evaluate their industrial potentials and suitability as raw materials. Fifteen representative clay samples were collected from the study area. The mineralogy and chemical composition of samples was analyzed using X-ray diffractometer (XRD) and inductively coupled plasma-mass spectrometer (ICPMS) techniques. Mineralogical analysis of samples indicates that kaolinite and nontronite are the major clay minerals present while quartz is the major non-clay mineral. Other non-clay minerals include orthoclase, labradorite and albite in lesser amounts. Major element abundances of SiO₂ (ca.58.03%), Al₂O₃ (ca.13.38%) and Fe₂O₃ (ca.7.66%) represent more than 70% of the bulk chemical compositions while CaO, MgO, Na₂O, K₂O, MnO, TiO₂ and P₂O₅ relatively have low values. Detrital orthoclase feldspar, albite and labradorite in the clay samples suggests that it has not yet reached maturity while moderately high ferric oxide imparted a reddish brown colorization. Assessment of industrial suitability of the Sosan clay based on the mineralogy, geochemistry, physical properties and the fine nature of the clay and also with appropriate processing which include screening of quartz and iron oxide minerals and bleaching, the clay materials could serve as raw materials for paints, traditional ceramic pots, cosmetics, building bricks and for waste water treatment. The silica sesquioxide and alumina-iron ratio are within the range considered for utilization in the manufacture of good quality cement.