A review on the management of arsenic-laden spent adsorbent: Insights of global practices, process criticality, and sustainable solutions

Adsorption is a widely used arsenic remediation technique due to its high efficacy, economic value, ease in operation and maintenance, and other multiple factors. However, the proper management of arsenic-laden spent media is one of the major challenges, which affects the sustainability of this treatment technique in field-scale implementations. This review summarizes the various adsorbents and their regeneration/reuse for the remediation of arsenic from aqueous solution, as well as the several safe management practices, such as landfilling, incineration, stabilization in construction material, etc., for the arsenic-laden spent media. In most of the developing countries disposal of spent media is a major concern, and in many instances, the ecotoxic effects to the environment concerning its direct disposal imposed a critical hindrance on this process. Furthermore, the present study reviewed the physicochemical characteristics of spent media, generation of secondary pollution, ecotoxicological effects, and factors that affect the leaching of arsenic. A brief overview of several methods that determine the leaching from arsenic spent media exhibited that toxicity characteristic leaching procedure is widely practiced in spite of some limitations to simulate the landfill conditions. The sustainability assessment framework for spent adsorbent is developed and it was observed that the stabilization/solidification is more environmentally friendly but less cost-effective. The review highlighted the field practices of spent adsorbent management across the globe critically, which streamline the research need in adsorptive removal of arsenic as well as instigate proper selection of techniques for case-specific implementations. (C) 2022 The Authors. Published by Elsevier B.V.

Automated summary

Adsorption is widely used for arsenic remediation, but the proper management of arsenic-laden spent media remains a major challenge. This review summarizes the various adsorbents and their reuse methods, as well as safe management practices. It also discusses the characteristics, pollution, leaching factors, and sustainability assessment framework of spent media. The review critically examines the field practices of spent adsorbent management and provides guidance for further research and implementation.