Removal of Persistent Organic Pollutants (POPs) from water and wastewater by adsorption and electrocoagulation process

Abstract

The intensification of industrial activities significantly increases the distribution of toxic substances and other non-biodegradable pollutants from industrial wastewater to the environment. Among these contaminants, Persistent Organic Pollutants (POPs) are considered harmful to humans, wildlife, and plants. In order to find a solution that can improve the water quality and protect the environment, interest in wastewater treatment has intensified over the last decades. Separation techniques, i.e., adsorption process, coagulation, and electrocoagulation, have proven to be more effective in removing target pollutants and largely comply with discharge legislation. Each of these methods has its own specific merits, difficulties, and parameters that affect the removal efficiency. In this document, these methods have been reviewed on the basis of recently published relevant literature. Batch and continuous modes of adsorption and electrocoagulation have been discussed. For the adsorption process, this review elucidated the adsorption isotherms, kinetic models, breakthrough curve modeling, thermodynamic studies, and the regeneration of the support used either in batch and continuous reactors. Likewise, the state of the art of electrocoagulation was clarified, highlighting the benefit of the electrocoagulation-adsorption hybrid process to enhance the removal efficiency of organic pollutants from wastewaters.