TITLE:
Utilisation of Agro-Wastes as Adsorbents for Fluoride and Co-Existing Ions Adsorption from Groundwater Sourced from Bongo, Ghana
AUTHORS:
Ishmael Quaicoe, Nikao Adziman Lasidzi, Lyanne Korkor Amartey, Seifudeen Simeon
KEYWORDS:
Defluoridation, Biomass, Adsorption Capacity, Fluoride Ion, Adsorption, Bongo
JOURNAL NAME:
Journal of Geoscience and Environment Protection,
Vol.13 No.4,
April
18,
2025
ABSTRACT: Fluoride (F) contamination of groundwater through natural or anthropogenic activities presents health concerns to communities that depend on it as a source of drinking water. This study examined the levels of F− and co-existing ions present in groundwater sourced from Bongo, a community in Ghana. The adsorption efficiencies and capacities using agro-waste (millet stocks and groundnut shells) for the removal of these ions from the groundwater were also assessed. The findings revealed that the mean concentration of F− is 2.24 mg/L, which exceeded the permissible standard of WHO/GSA. The presence of co-existing ions in the groundwater with their mean concentration were 22.4, 45, 56.48, and 18.08 for Cl−, SO42-, PO43-, Mg2+, K+, respectively. The results showed that the adsorbents could effectively remove fluoride from the groundwater, with maximum adsorption capacities (and removal efficiencies) of 0.021 mg/g (37.95%), 0.016 mg/g (28.10%) and 0.015 mg/g (26.30%) for charred millet, groundnut husk and uncharred millet, respectively. Similarly, the adsorbents were able to remove the co-existing ions at varying adsorption efficiencies. In terms of behaviour, the fluoride adsorption was initially quick (2 h) followed by slow adsorption. The adsorption kinetic of the fluoride removal best fitted pseudo-second order model. Notably, commercially sourced anthracite exhibited similar behaviour but superior performance relative to the agro-waste adsorbents used for the study. The findings suggest that these abundant agro-waste adsorbents are promising and sustainable materials for fluoride and co-existing ions removal from contaminated groundwater.