Paper Title
ELIMINATION OF A POLLUTANT FROM WATER THROUGH THE USE OF AN ADSORBENT. A DFT STUDY

Abstract
Abstract - The adsorption mechanism of metronidazole on polypyrrole (PPY) surface sites was characterized by quanto-chemical calculations using the DFT method. An electrophilic character of metronidazole and nucleophilic of PPy as well as the electrophilic and nucleophilic zones responsible for the non-covalent interaction in the physisorption of metronidazole on PPy processes within the framework of the decontamination of the water of this drug have been deduced by calculations of the global indices of the conceptual DFT and the MEP molecular electrostatic potential. The adsorption mechanism of metronidazole on PPy was mainly governed by the physical interactions (hydrogen bonds) at the adsorbate/adsorbent interface (figure 1), these energetic and structural results clearly indicating that the process is a physisorption. These structural and energetic procedures are in good agreement with the experimental results. An irreversible and exothermic phenomenon of physical adsorption has been shown by thermochemical enthalpy and entropy calculations. In summary, PPy can be used as an environmentally friendly and effective adsorbent material for the removal of metronidazole and possibly other pharmaceutical pollutants from hospital and municipal wastewater. Figure 1: Metronidazole adsorption on polypyrrole Keywords - Water Purification, Metronidazolz Pharmaceucal Polluents, Polypyrrole Adsorbent Material, DFT Simulation