Beneficiation and Characterisation of Kaolin Clay from Clay Deposit in Kutigi, Niger State, Nigeria

Abstract

Kaolin is widespread across Niger State in Nigeria, relatively free of charge, non-toxic and environmentally friendly. In this study, kaolin clay from Kutigi, Niger State, Nigeria was beneficiated and characterised for their crystal structure and morphology using X-Ray Diffractometer (XRD), Dispersive X – Ray Fluorescence (XRF) Machine, High Resolution Transmission Electron Microscope (HRTEM) and Brunauer – Emmett – Teller (BET) Nitrogen Absorption Analyser. The average crystallite size of the raw kaolin and Beneficiated Kaolin Clay (BKC) was calculated to be 40.258nm and 28.114nm respectively. The XRD analysis showed that the BKC had four (4) different phases of kaolinite: Al(Si2O5)(OH)4, kaolinite 1Md – AlSi2O5(OH)4, quartz – SiO2 and muscovite – KAl2 (Si3Al)O10(OH)2. XRF analysis showed a SiO2/Al2O3 ratio of 1.54 and 1.35 in raw and BKC respectively. The Selected Area Electron Diffraction (SAED) pattern showed that the raw clay and BKC were polycrystalline in nature with each bright spots reflecting individual peaks. The Bet analyses showed that the adsorption-desorption isotherms for the BKC possessed pore size of mesopore widths between 13.8994 nm, surface area of 14.5126 m2g1, pore volume of 0.003740 cm3/g and adsorption average diameter of 1.0309 nm. This research work showed that kaolin clay from Kutigi is poly-crystallinity in nature and could be used as adsorbent for wastewater treatment