Recent advances in the adsorptive removal of heavy metals from acid mine drainage by conventional and novel materials: A review

Abstract

Coal mining activities have widespread and detrimental effects on the environment and human health, primarily attributable to the generation of acid mine drainage (AMD). AMD is characterized by its low pH and high heavy metal content, posing significant risks to ecosystems and human populations alike. Extensive research has focused on the adsorption-based removal of heavy metals from AMD, involving the development of both conventional and innovative materials aimed at addressing this challenge. However, the practical application of these materials faces obstacles such as limited availability, complex preparation processes, and sensitivity to pH conditions. Effectively addressing this issue requires the identification of cost-effective and abundant materials that demonstrate consistent efficacy across diverse environmental conditions. Additionally, considering the potential for reusability and integration within a circular economy framework is crucial. This study offers a comprehensive overview of the current research landscape pertaining to heavy metal removal from AMD through adsorption. It includes a systematic categorization of heavy metals, an examination of their environmental and human health impacts, a comparative analysis of the performance of conventional and novel materials, an exploration of the influence of material preparation techniques and solution pH, and an assessment of the potential for reusability and circular economy integration. By consolidating and analyzing existing knowledge, this study provides valuable insights and serves as a valuable resource for researchers engaged in heavy metal removal from AMD. Moreover, it addresses significant knowledge gaps in this field, contributing to the advancement of sustainable solutions for AMD mitigation and environmental protection.