Layered transition metal chalcogenides for the removal of elemental mercury from flue gas: a review

Abstract

Mercury and its compounds pose a significant threat to both ecological systems and human health due to their high toxicity and persistence in the environment. Controlling mercury emissions from flue gas, a major source of mercury pollutants, is considered a key task in ecological and environmental management and has garnered extensive research attention. Compared to traditional metal sulfide elemental mercury removal adsorbents, layered transition metal chalcogenides demonstrate superior performance in flue gas mercury removal due to their unique structure, which provides more abundant sulfur active sites. In this context, this study describes transition metal chalcogenides with layered structures used for flue gas mercury removal. In order to better utilize the structural advantages of layered transition metal chalcogenides, the modification methods of the adsorbents are discussed. Subsequently, the performance of the adsorbents for elemental mercury removal in complex flue gas environments was analyzed, along with a discussion of their recovery methods and regeneration performance. To further understand the underlying principles of elemental mercury removal by adsorbents, this article explores the mechanism of mercury removal from layered transition metal chalcogenide adsorbents based on experiments and machine learning to analyze possible reaction processes and adsorption pathways. However, overall, there are still areas for improvement in the study of elemental mercury removal by adsorbents of layered transition metal chalcogenide adsorbents. Therefore, this study presents several strategies to enhance their adsorption capacity for elemental mercury. This study serves as a reference for the design and development of adsorbents for elemental mercury removal using layered transition metal chalcogenides.