Discipline: Ecology Environmental and Earth Sciences
Subcategory: Environmental Engineering
Jameese McCray - Southern University and A&M College
Co-Author(s): Brandon Hart
The World Health Organization recommends that the desirable intake of fluoride concentration in drinking water to be 0.5 to 1.5 ppm. An overburdened of drinking water containing a fluoride concentration above 1.5 ppm can cause dental fluorosis and skeletal fluorosis. In the Bongo District, located in the northeast region of Ghana, the groundwater contains fluoride concentrations that are above 1.5 ppm. In order to address this issue, International Research Students from the United States collaborated with Kwame Nkrumah University of Science and Technology (KNUST) in Kumasi, Ghana to develop a low cost and sustainable method to remove the fluoride from the drinking water sources. In this study, heating laterite at 500 ℃ for 2 hours along with alumina oxide showed to improve the adsorbent ability of fluoride. Fluoride adsorption tests were conducted using 2g of heat treated laterite modified with solutions of alumina oxide added to 50 mL of a sodium fluoride solution. The lowest fluoride concentration received from this study was with the initial fluoride concentration at 40 mg/L and the final concentration was 10.5 mg/L after 90 minutes. During the fluoride adsorption test, the fluoride concentration did not meet the standards for safe drinking water, however an increase in time using the laterite modification can reduce the fluoride concentration below 1.5 ppm. Overall, the modified laterite significantly reduced the fluoride concentration within the timeframe. Using the Langmuir and Freundlich Isotherm models, the adsorption efficiency was examined. The correlation coefficient R2 showed that the Freundlich isotherm model fit the experimental data slightly better than the Langmuir isotherm model. The fluoride was adsorbed by the laterite-alumina in multiple layers.
Funder Acknowledgement(s): NSF; International Research Experience for Student
Faculty Advisor: Samuel Ibekwe, email@example.com
Role: I did the full procedure and testing for the adsorption experiment using Laterite-Alumina. I also used kinetic models to calculate the adsorption rate of fluoride using laterite-alumina. I model the results usingthe Langmuir and Freundlich Isotherm models. I wrote most of the report as well as the abstract for this experiment.