REVIEW ARTICLE Removal of mercury by adsorption: a review Jin-Gang Yu 1 & Bao-Yu Yue 1 & Xiong-Wei Wu 2 & Qi Liu 1 & Fei-Peng Jiao 1 & Xin-Yu Jiang 1 & Xiao-Qing Chen 1,3 Received: 12 August 2015 /Accepted: 24 November 2015 /Published online: 1 December 2015 # Springer-Verlag Berlin Heidelberg 2015 Abstract Due to natural and production activities, mercury contamination has become one of the major environmental problems over the world. Mercury contamination is a serious threat to human health. Among the existing technologies available for mercury pollution control, the adsorption process can get excellent separation effects and has been further stud- ied. This review is attempted to cover a wide range of adsor- bents that were developed for the removal of mercury from the year 2011. Various adsorbents, including the latest adsorbents, are presented along with highlighting and discussing the key advancements on their preparation, modification technolo- gies, and strategies. By comparing their adsorption capacities, it is evident from the literature survey that some adsorbents have shown excellent potential for the removal of mercury. However, there is still a need to develop novel, efficient ad- sorbents with low cost, high stability, and easy production and manufacture for practical utility. Keywords Adsorption . Adsorbents . Mercury . Removal . Properties Introduction Mercury (Hg) is a naturally occurring element. It is widely used in electricity generation and industrial production such as chlor-alkali, plastics, metallurgy, and electronics. The two main oxidation states of Hg are +1 [Hg(I)] and +2 [Hg(II)] (Pervukhina et al. 1999). Mercury sulfide (HgS) is clinical used in Chinese and Indian traditional drugs, such as cinnabar and BRasasindura,^ which might have little or no therapeutic effects because it may not react with any cell receptors due to its insolubility in aqueous solution (Kamath et al. 2012). Mercury chloride (HgCl 2 ) was widely used in producing poly- vinyl chloride. A higher oxidation state for Hg is +4 [Hg(IV)], which has been detected only under exceptional conditions, e.g., Hg(IV) fluoride (HgF 4 ) (Wang et al. 2007). Another highly toxic form of Hg(II), methylmercury [MeHg, (CH 3 Hg + )X - ], is a bioaccumulative environmental toxicant which can be enriched in fish, shellfish, and animals that eat fish (Choi et al. 2008). Due to its volatility, persistence, and bioaccumulation, Hg has been considered as one of the most toxic metals which can affect the health of human beings. Long-term exposure to large amounts of Hg would harm the human brain, heart, kidneys, lungs, and even the immune system (Hsiao et al. 2011). Exposure to Hg in the womb or fed with seafood con- taining MeHg may harm the developing nervous system of unborn babies and young children and reduce their IQs (Yau et al. 2014). Elemental (metallic) Hg [Hg 0 ] adsorbed through the lungs can cause health effects such as tremors, muscle atrophy, headaches, and so on when it is breathed as a vapor. However, the amount of Hg discharged into the environment is increasing continuously. Carbonaceous fuel combustion such as coal-fired plants and incinerators has contributed a lot of the current global Hg emissions. Up to now, Hg can be found in water, rocks, and soil. Additionally, trace amounts of * Jin-Gang Yu yujg@csu.edu.cn 1 College of Chemistry and Chemical Engineering, Central South University, Changsha, Hunan 410083, China 2 College of Science, Hunan Agricultural University, Changsha, Hunan 410128, China 3 Collaborative Innovation Center of Resource-Conserving and Environment-Friendly Society and Ecological Civilization, Changsha, Hunan 410083, China Environ Sci Pollut Res (2016) 23:5056–5076 DOI 10.1007/s11356-015-5880-x Responsible editor: Philippe Garrigues