Abstract
In this study, aluminosilicate rich clay soils were prepared through mechanochemical activation. The chemical and mineralogical properties were investigated using X-Ray Fluorescence (XRF) and X-ray diffraction (XRD). The functional groups, morphology and surface area were evaluated using Fourier Transform Infra-Red (FTIR), Scanning electron microscopy (SEM) and Brunauer-Emmett-Teller (BET) analysis. Batch experiments were used to evaluate its defluoridation efficiency while antibacterial activities were assessed using well diffusion method. Maximum adsorption capacity was found to be 1.87 mg/g with 32% fluoride removal. Fluoride adsorption was found to reduce in the presence of Cl−, PO42− and CO32− while it increased in the presence of SO42− and NO3−. Adsorption data fitted well to Freundlich isotherms, hence, confirming heterogeneous multilayer adsorption. Kinetic studies revealed that fluoride adsorption fitted well to pseudo-second order model. The sorption of F− onto the clays’ surface followed intra-particle diffusion mode. High correlation coefficient indicates that the sorption process was greatly controlled by particle diffusion while it is minimal in pore diffusion model. Antibacterial studies revealed no zone of inhibition for all the activated clays, hence indicating that they are not active against the bacterial strains of Escherichia coli used in this study. The results showed activated clays’ potential for defluoridation. Its effectiveness in pathogen removal is limited. Hence further modifications of the clays’ surfaces are hereby recommended.
Highlights
Water is an essential resource necessary for human health and survival
The fluoride levels in the activated clay was found to be much lower than the World Health Organization [18,19,20] and South
The results show that activation increases the surface area of the clay from 10 min to 30 min (17.1 m2 /g) and thereafter decrease to about 13 m2 /g at 60 min treatment time, clay sample D which was activated for 30 min is considered optimum for the modification process since the sample has the highest surface area and pore volume suggesting that it has more active sites for fluoride uptake, thereby improving the quality of the clay as a good adsorbent for fluoride removal
Summary
Water is an essential resource necessary for human health and survival. Groundwater is one of the major sources of potable water which is becoming increasingly contaminated as a result of natural and anthropogenic activities worldwide. Fluoride is one of the various water contaminants. High fluoride levels above the permissible limit cause fluorosis. The presence of pathogens in water leads to various types of water borne diseases. Different types of clays and some metal oxide-coated aluminosilicate materials have been used in defluoridation and pathogen removal, but they are not totally active against bacterial strains. Clay minerals are naturally occurring fine grained phyllosilicate minerals which impart plasticity to clay and harden when dried or fired [1].
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: International Journal of Environmental Research and Public Health
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
