Assessing the performance of green nano Zero Valent Iron in column experiments for the removal of NSAIDs from water

The existence of emerging contaminants in the aquatic environment is globally a major concern. Among them, non-steroidal anti-inflammatory drugs (NSAIDs) are a vast category of pharmaceuticals that are widely consumed and cannot be completely removed in typical wastewater treatment systems, thus entering the environment and causing adverse effects on living organisms and human health. Nano Zero Valent Iron (nZVI) has been proved capable of removing a wide range of recalcitrant pollutants from contaminated water and soil. Its reactivity, and large specific surface area, in combination with the ability to be produced via ‘green’ low-cost methods make it a promising material for the reclamation of wastewater from persistent micropollutants. In this study, nZVI made of green tea extracts, was incorporated in a cationic resin and was used in continuous flow pilot experiments to investigate the removal efficiency of two nonsteroidal anti-inflammatory drugs NSAIDs from wastewater, namely Naproxen and Ketoprofen. Results indicated that the nZVI columns exhibited improved performance to the removal of these pharmaceuticals for the lowest initial concentration of pollutants and for the largest bed height investigated, but pH also played a key role on the overall process performance.