DFT Study of Chlorothalonil Adsorption on Illite Clay for Depollution

The use of pesticides such as chlorothalonil in agriculture allows agricultural production intensification for satisfying the market demand. However, chlorothalonil utilization leads to groundwater and drinking contamination with its transformation products (TPs). Hence, chlorothalonil needs to be removed from contaminated water to avoid humans and ecosystems exposure to the pollutant and its TPs. Adsorption is the most suitable technique for recovering pesticides. Based on Density Functional Theory as implemented in VASP simulation code, the present work assessed the adsorption of chlorothalonil on the surface of illite, which is an abundant clay throughout the world, particularly in Benin. The present work showed that chlorothalonil adsorption on illite is exoenergetic, involving mainly van der Waals interactions and hydrogen bonds. Therefore, illite appears as a good candidate for the design of water depollution filters.