Adsorptive Removal of Iron and Manganese from Groundwater Samples in Ghana by Zeolite Y Synthesized from Bauxite and Kaolin

Abstract

Ground water samples from residential homes in three Regions of Ghana: Central, Greater Accra and Ashanti, were analyzed for iron and manganese contamination. The samples were exposed to characterized zeolite Y by X-ray diffraction, scanning electron microscopy, energy dispersive x-ray spectroscopy, Fourier transformed-infrared spectroscopy and thermos gravimetric-differential thermal analysis. Zeolite Y is able to remove 98% of iron and 97% of manganese within an hour. The adsorption of both iron and manganese follows the Freundlich model, whilst the kinetic studies show that pseudo-first order and intra particle and film diffusion models provided the best fit, suggesting the transport of the ions onto the zeolite Y surface and the subsequent diffusion into the zeolite Y framework. The adsorption at 0.2 mg L−1 Fe (𝑄0.2) is calculated to be 0.023 mg g−1 for the Freundlich adsorption model, whilst that of manganese at 0.05 mg L−1 Mn (𝑄0.05) is evaluated to be 0.015 mg g−1. The zeolite retains its adsorption properties when retrieved from the first exposure water sample, washed copiously with distilled water and added to fresh water samples. The results suggest that zeolite Y can be used as a potential adsorbent for the removal of iron and manganese from groundwater.