Environmental Chemistry

Project

Removing of Persistent Organic Pollutants and transition metals from polluted water by using a modified montmorillonite clay nanomaterial

Water pollution is one of the biggest concerns as a potential hazard for the environment and therefore for human health. Contaminants of emerging concern (CECs) are increasingly being observed and identified in water samples across the world and their risks require further investigation. The breadth of such compounds is increasing and need reliable analytical methods to detect them even at low concentrations. The petrochemical past of Azerbaijan as part of the Former Soviet Union has led to significant production and use of Persistent Organic Pollutants (POPs) which now needs to be taken into consideration. Several studies have shown that nonnegligible concentrations of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) have been reported in water, air, and surface soil in an extensive sampling across Azerbaijan, as well as contamination with transition metal like Cr, Ni, and Pb.
The aim of this project is to develop environmentally friendly nanomaterials for detecting and removing the POPs and transition metal ions in freshwater systems using innovative modified montmorillonite (Mt) clay minerals. This study will be coupled with mathematical modeling to represent the behavior in outdoor conditions. Two main POPs will be studied: thiamethoxam because of its low sorption coefficient and its susceptibility to hydrolysis and photolysis, and the PCBs for their wide usage and high toxicity for the environment. Since POPs are negatively charged, we suggested modifying Mt with cationic surfactant in order to make novel organoclay to detect and remove them from water. Several organoclays has been synthesized for capturing organic pollutants but some of them are not environment friendly as they are constituted with non-water friendly elements. Thereby we decided to use surfactants based on betaine glycine which is subsequently degraded up to 70% by aerobic microorganisms within 28 days of incubation. In addition, Mt can be functionalized with semiconductors. Firstly, TiO2 for its ability to break down organic pollutants and achieve complete mineralization, and its photocatalytic and hydrophilic properties makes it close to an ideal catalyst due to its high reactivity, reduced toxicity, chemical stability, and low costs. Secondly, graphene oxide (GO, product of graphite’s oxidation), which is considered as a super adsorbent in water treatment, because of its excellent water solubility and high surface area.

Axis coordinator: Maurice Millet

Permanent researcher: none

PhD students: Narinj Taghiyeva

Master students: (to come)