Recent advances on sustainable removal of emerging contaminants from water by bio-based adsorbents

Abstract

Contaminants of emerging concern (CECs) are a new class of pollutants that may pose environmental and human risks. Such contaminants are prevalent in the environment as they can’t be easily eliminated completely by traditional processing of wastewater discharge due to their obstinate nature. Adsorption is one such technique that is efficient, straightforward, convenient, comparatively inexpensive and sustainable for removing CECs from water on a large scale. Many review articles have been published recently on biochar and its composites derived from several agricultural waste sources for the removal of organic contaminants from water by adsorption. However, a detailed mechanistic aspect of adsorption of CECs on various bio-based adsorbents is scarcely reported. Additionally, the regeneration and stability of bio-based adsorbents need specific consideration. The present work collates studies reported in the last couple of decades on bio-based adsorbents and their composites for CEC removal with the aim to provide insights into the mechanism of adsorption, regeneration and stability of bio-based adsorbents to enable researchers to design a bio-based adsorbent for sustainable removal of CECs from water. The advantages and disadvantages of bio-based adsorbents are also argued. In the end, some key recommendations are made to improve CEC removal from water using bio-based adsorbents.