Green synthesized zinc oxide nanoparticles for removal of carbamazepine in water and soil systems

Abstract

During the COVID-19 pandemic, there was a significant increase in pharmaceutical releases (4 %), which created a pressing global need for solutions. In this study, we explored the use of zinc oxide nanoparticles (GS-ZnONPs) derived from neem (Azadirachta indica) leaves for separating antiepileptic drug carbamazepine (CBZ) from wastewater. CBZ is a major emerging pollutant in wastewater that can be reused for various purposes, including food production and drinking water. The study found that the GS-ZnONPs were effective in removing CBZ from water, with an adsorption capacity of 27.55 mg g−1 at room temperature. The GS-ZnONPs, under optimal conditions of pH 5.0, 100 mg of adsorbent, and 12 mg L−1 of CBZ at 25 °C ± 2 °C, demonstrated a remarkable removal efficiency, successfully eliminating 92.89 % of CBZ from water. Additionally, the study found that CBZ binds strongly to GS-ZnONPs, making them effective for removing CBZ from soil as well. The results suggest that GS-ZnONPs synthesized from neem leaves could be a low-cost and sustainable solution for removing emerging pollutants from wastewater and soil. Future studies could investigate the adsorption mechanisms, functional groups, respective pH ranges, and reuse of these low-cost adsorbents to further optimize their efficiency in tackling emerging pollutants.