Adsorption Kinetics and Contaminant Removal Efficiency of Nitrate and Phosphate Using Various Adsorbents.

Abstract

Nitrate and phosphate play critical functions in plant development, yet their extensive usage in agriculture and industry pollutes water. This not only leads to diseases like cancer but also promotes the environmentally harmful process of eutrophication. Despite significant studies on phosphate and nitrate ion removal from water, the problem is in developing highly selective adsorbents to improve removal efficiency. This study provides a thorough evaluation of the effectiveness of nitrate and phosphate removal from synthetic solutions using three different adsorbents: Powdered activated carbon (PAC), modified activated carbon (MAC), and Activated Alumina (AA). Batch adsorption experiments were carried out across a variety of time periods and doses to investigate the dynamic interactions between the adsorbents and pollutants. The results showed that MAC treated with FeCl3 had the best nitrate removal effectiveness of 97%, outperforming PAC and AA. Conversely, AA demonstrated superior phosphate removal efficiency, outperforming MAC and PAC. The pseudo-second-order kinetic model was shown to be the best fit for modeling the adsorption kinetics, offering useful insights into the time-dependent adsorption processes for both nitrate and phosphate. This study's findings not only help in the optimization of water treatment operations but also highlight the significance of selecting the suitable adsorbent for certain pollutants. The findings of this study benefit environmental science and water treatment technologies by offering practical insights into the comparative performance of commonly utilized adsorbents. The discovery of MAC as a powerful nitrate removal agent and AA as a phosphate removal agent has implications for the development of efficient, customized water treatment applications.