Studies of Effects of Hydrochloric Acid Treatment on the Chemical Composition of Kaolin Clay

Abstract

The effect of hydrochloric acid treatment on the chemical composition of kaolin clay from Awgu Town in Awgu Local Government Area of Enugu State was studied in this work. The raw clay was mined, soaked in water to remove dirt, and sun-dried, followed by grinding to a particle size of 0.075mm. The fine sized sample was then treated with 1M hydrochloric acid. Characterization of the untreated and treated clay samples with x-ray fluorescence (XRF) spectrometry revealed that the samples consist mainly of silica (SiO2), alumina (Al2O3), and iron oxide (Fe2O3) with potassium oxide (K2O), titanium oxide (TiO2), manganese oxide (MnO) and other oxides occurring as minors. The study further revealed that the percentage composition of SiO2,  Al2O3 and MnO increased with hydrochloric acid treatment, while Al2O3,  TiO2 and  K2O were removed/decreased appreciably with hydrochloric acid treatment. The acid treatment using HCl enhanced the chemical composition of kaolin clay. Kaolin clay from Awgu possesses some industrial potentials for the manufacture of glass, ceramics, refractory bricks, paint and high melting clay based on its chemical composition. More studies should be carried out using other clay treatment processes apart from HCl activation, and characterization techniques like atomic absorption spectroscopy (AAS), scanning electron microscope (SEM), Fourier transform infrared (FTIR), x-ray diffraction (XRD) and energy-dispersive x-ray (EDX) spectroscopy in the determination of the mineralogical phases/compositions of kaolin clay from Awgu Town, and how they relate to its application, as Awgu clay is one of the unidentified clays in Nigeria.