Mercury Stable Isotope Fractionation During Coal Combustion in Coal-Fired Boilers: Reconciling Atmospheric Hg Isotope Observations with Hg Isotope Fractionation Theory

  • Ruoyu SunEmail author
Focused Review


Mercury (Hg) stable isotope is a useful tool to understand the transformation of atmospheric Hg. The observation on the enrichment of heavier isotopes in gaseous elemental Hg (GEM) relative to oxidized HgII species in atmosphere cannot be convincingly explained by isotope fractionation of Hg redox processes. This review shows that the large Hg isotope mass dependent fractionation (MDF) in coal-fired boilers is one of the underlying reasons. The reported Hg isotope data of feed coals and their combustion products are first summarized to give a general overview of how Hg isotopes fractionate before Hg discharge from coal-fired boilers. Then, predictive MDF models are discussed to simulate δ202Hg values of different Hg species in coal combustion flue gases. The discharged GEM is predicted to have the highest δ202Hg followed by gaseous HgII and particulate-bound HgII, which is in consistent with the observed MDF pattern of atmospheric Hg species.


Mercury isotope Mass dependent fractionation Mass independent fractionation Coal combustion Atmospheric mercury 



This work was supported by the National Key Research and Development Plan (2016YFC0201600; 2017YFC0212700) and the National Natural Science Foundation of China (41773104; 41602167; U1612442).

Supplementary material

128_2018_2531_MOESM1_ESM.xlsx (36 kb)
Supplementary material 1 (XLSX 35 KB)


  1. Bergquist BA, Blum JD (2007) Mass-dependent and -independent fractionation of Hg isotopes by photoreduction in aquatic systems. Science 318:417–420CrossRefGoogle Scholar
  2. Blum JD, Bergquist BA (2007) Reporting of variations in the natural isotopic composition of mercury. Anal Bioanal Chem 388:353–359CrossRefGoogle Scholar
  3. Blum JD, Sherman LS, Johnson MW (2014) Mercury isotopes in earth and environmental sciences. Annu Rev Earth Planet Sci 42:249–269CrossRefGoogle Scholar
  4. Chen J, Hintelmann H, Feng X, Dimock B (2012) Unusual fractionation of both odd and even mercury isotopes in precipitation from Peterborough, ON, Canada. Geochim Cosmochim Acta 90:33–46CrossRefGoogle Scholar
  5. Coufalík P, Krmíček L, Zvěřina O, Meszarosová N, Hladil J, Komárek J (2018) Model of mercury flux associated with volcanic activity. Bull Environ Contam Toxicol 101:549–553CrossRefGoogle Scholar
  6. Das R, Wang X, Khezri B, Webster RD, Sikdar PK, Datta S (2016) Mercury isotopes of atmospheric particle bound mercury for source apportionment study in urban Kolkata, India. Elem Sci Anth 4:000098CrossRefGoogle Scholar
  7. Demers JD, Blum JD, Zak DR (2013) Mercury isotopes in a forested ecosystem: Implications for air-surface exchange dynamics and the global mercury cycle. Global Biogeochem Cycles 27:222–238CrossRefGoogle Scholar
  8. Demers JD, Sherman LS, Blum JD, Marsik FJ, Dvonch JT (2015) Coupling atmospheric mercury isotope ratios and meteorology to identify sources of mercury impacting a coastal urban-industrial region near Pensacola, Florida, USA. Global Biogeochem Cycles 29:1689–1705CrossRefGoogle Scholar
  9. Donovan PM, Blum JD, Yee D, Gehrke GE, Singer MB (2013) An isotopic record of mercury in San Francisco Bay sediment. Chem Geol 349–350:87–98CrossRefGoogle Scholar
  10. Driscoll CT, Mason RP, Chan HM, Jacob DJ, Pirrone N (2013) Mercury as a global pollutant: sources, pathways, and effects. Environ Sci Technol 47:4967–4983CrossRefGoogle Scholar
  11. Enrico M, Roux GL, Marusczak N, Heimbürger LE, Claustres A, Fu X, Sun R, Sonke JE (2016) Atmospheric mercury transfer to peat bogs dominated by gaseous elemental mercury dry deposition. Environ Sci Technol 50:2405–2412CrossRefGoogle Scholar
  12. Fu X, Marusczak N, Wang X, Gheusi F, Sonke JE (2016) Isotopic composition of gaseous elemental mercury in the free troposphere of the Pic du Midi observatory, France. Environ Sci Technol 50:5641–5650CrossRefGoogle Scholar
  13. Ghosh S, Schauble EA, Lacrampe Couloume G, Blum JD, Bergquist BA (2013) Estimation of nuclear volume dependent fractionation of mercury isotopes in equilibrium liquid–vapor evaporation experiments. Chem Geol 336:5–12CrossRefGoogle Scholar
  14. Gratz LE, Keeler GJ, Blum JD, Sherman LS (2010) Isotopic composition and fractionation of mercury in Great Lakes precipitation and ambient air. Environ Sci Technol 44:7764–7770CrossRefGoogle Scholar
  15. Horowitz HM, Jacob DJ, Zhang Y, Dibble TS, Slemr F, Amos HM, Schmidt JA, Corbitt ES, Marais EA, Sunderland EM (2017) A new mechanism for atmospheric mercury redox chemistry: implications for the global mercury budget. Atmos Chem Phys 17:6353–6371CrossRefGoogle Scholar
  16. Hower JC, Senior CL, Suuberg EM, Hurt RH, Wilcox JL, Olson ES (2010) Mercury capture by native fly ash carbons in coal-fired power plants. Prog Energy Combust Sci 36:510–529CrossRefGoogle Scholar
  17. Huang Q, Chen J, Huang W, Fu P, Guinot B, Feng X, Shang L, Wang Z, Wang Z, Yuan S, Cai H, Wei L, Yu B (2016) Isotopic composition for source identification of mercury in atmospheric fine particles. Atmos Chem Phys 16:11773–11786CrossRefGoogle Scholar
  18. Huang S, Yuan D, Lin H, Sun L, Lin S (2017) Fractionation of mercury stable isotopes during coal combustion and seawater flue gas desulfurization. Appl Geochem 76:159–167CrossRefGoogle Scholar
  19. Huang S, Sun L, Zhou T, Yuan D, Du B, Sun X (2018) Natural stable isotopic compositions of mercury in aerosols and wet precipitations around a coal-fired power plant in Xiamen, southeast China. Atmos Environ 173:72–80CrossRefGoogle Scholar
  20. Jiskra M, Wiederhold JG, Skyllberg U, Kronberg R-M, Hajdas I, Kretzschmar R (2015) Mercury deposition and Re-emission pathways in boreal forest soils investigated with Hg isotope signatures. Environ Sci Technol 49:7188–7196CrossRefGoogle Scholar
  21. Lee CW, Serre SD, Zhao Y, Lee SJ, Hastings TW (2008) Mercury oxidation promoted by a selective catalytic reduction catalyst under simulated powder river basin coal combustion conditions. J Air Waste Manage Assoc 58:484–493CrossRefGoogle Scholar
  22. Lin C-J, Pehkonen SO (1999) The chemistry of atmospheric mercury: a review. Atmos Environ 33:2067–2079CrossRefGoogle Scholar
  23. Obrist D, Agnan Y, Jiskra M, Olson CL, Colegrove DP, Hueber J, Moore CW, Sonke JE, Helmig D (2017) Tundra uptake of atmospheric elemental mercury drives Arctic mercury pollution. Nature 547:201–204CrossRefGoogle Scholar
  24. Peng F, He T, Li Z, Chen M, Qian X, Zeng L, Xu Y (2018) Enrichment characteristics and risk assessment of Hg in bird feathers from Caohai wetland in Guizhou Province, China. Acta Geochimica 37:526–536CrossRefGoogle Scholar
  25. Pirrone N, Cinnirella S, Feng X, Finkelman RB, Friedli HR, Leaner J, Mason R, Mukherjee AB, Stracher GB, Streets DG, Telmer K (2010) Global mercury emissions to the atmosphere from anthropogenic and natural sources. Atmos Chem Phys 10:5951–5964CrossRefGoogle Scholar
  26. Pyle DM, Mather TA (2003) The importance of volcanic emissions for the global atmospheric mercury cycle. Atmos Environ 37:5115–5124CrossRefGoogle Scholar
  27. Rolison JM, Landing WM, Luke W, Cohen M, Salters VJM (2013) Isotopic composition of species-specific atmospheric Hg in a coastal environment. Chem Geol 336:37–49CrossRefGoogle Scholar
  28. Schofield K (2008) Fuel-mercury combustion emissions: an important heterogeneous mechanism and an overall review of its implications. Environ Sci Technol 42:9014–9030CrossRefGoogle Scholar
  29. Selin NE, Jacob DJ, Park RJ, Yantosca RM, Strode S, Jaeglé L, Jaffe D (2007) Chemical cycling and deposition of atmospheric mercury: global constraints from observations. J Geophys Res 112:D02308CrossRefGoogle Scholar
  30. Senior CL (2006) Oxidation of mercury across selective catalytic reduction catalysts in coal–fired power plants. J Air Waste Manage Assoc 56:23–31CrossRefGoogle Scholar
  31. Sherman LS, Blum JD, Johnson KP, Keeler GJ, Barres JA, Douglas TA (2010) Mass-independent fractionation of mercury isotopes in Arctic snow driven by sunlight. Nat Geosci 3:173–177CrossRefGoogle Scholar
  32. Sherman LS, Blum JD, Douglas TA, Steffen A (2012a) Frost flowers growing in the Arctic ocean-atmosphere–sea ice–snow interface: 2. Mercury exchange between the atmosphere, snow, and frost flowers. J Geophys Res-Atmos 117:D00R10CrossRefGoogle Scholar
  33. Sherman LS, Blum JD, Keeler GJ, Demers JD, Dvonch JT (2012b) Investigation of local mercury deposition from a coal-fired power plant using mercury isotopes. Environ Sci Technol 46:382–390CrossRefGoogle Scholar
  34. Sherman LS, Blum JD, Dvonch JT, Gratz LE, Landis MS (2015) The use of Pb, Sr, and Hg isotopes in Great Lakes precipitation as a tool for pollution source attribution. Sci Total Environ 502:362–374CrossRefGoogle Scholar
  35. Sonke JE (2011) A global model of mass independent mercury stable isotope fractionation. Geochim Cosmochim Acta 75:4577–4590CrossRefGoogle Scholar
  36. Sonke JE, Blum JD (2013) Advances in mercury stable isotope biogeochemistry. Chem Geol 336:1–4CrossRefGoogle Scholar
  37. Sonke JE, Schäfer J, Chmeleff J, Audry S, Blanc G, Dupré B (2010) Sedimentary mercury stable isotope records of atmospheric and riverine pollution from two major European heavy metal refineries. Chem Geol 279:90–100CrossRefGoogle Scholar
  38. Stetson SJ, Gray JE, Wanty RB, Macalady DL (2009) Isotopic variability of mercury in ore, mine-waste calcine, and leachates of mine-waste calcine from areas mined for mercury. Environ Sci Technol 43:7331–7336CrossRefGoogle Scholar
  39. Streets DG, Horowitz HM, Jacob DJ, Lu Z, Levin L, ter Schure AFH, Sunderland EM (2017) Total mercury released to the environment by human activities. Environ Sci Technol 51:5969–5977CrossRefGoogle Scholar
  40. Sun R, Heimbürger L-E, Sonke JE, Liu G, Amouroux D, Berail S (2013) Mercury stable isotope fractionation in six utility boilers of two large coal-fired power plants. Chem Geol 336:103–111CrossRefGoogle Scholar
  41. Sun R, Sonke JE, Heimbürger L-E, Belkin HE, Liu G, Shome D, Cukrowska E, Liousse C, Pokrovsky OS, Streets DG (2014) Mercury stable isotope signatures of world coal deposits and historical coal combustion emissions. Environ Sci Technol 48:7660–7668CrossRefGoogle Scholar
  42. Sun G, Sommar J, Feng X, Lin C, Ge M, Wang W, Yin R, Fu X, Shang L (2016a) Mass-dependent and -independent fractionation of mercury isotope during gas-phase oxidation of elemental mercury vapor by atomic Cl and Br. Environ Sci Technol 50:9232–9241CrossRefGoogle Scholar
  43. Sun R, Sonke JE, Liu G (2016b) Biogeochemical controls on mercury stable isotope compositions of world coal deposits: a review. Earth Sci Rev 152:1–13CrossRefGoogle Scholar
  44. Sun R, Streets DG, Horowitz HM, Amos HM, Liu G, Perrot V, Toutain JP, Hintelmann H, Sunderland EM, Sonke JE (2016c) Historical (1850–2010) mercury stable isotope inventory from anthropogenic sources to the atmosphere. Elem Sci Anth 4:000091CrossRefGoogle Scholar
  45. Sun R, Jiskra M, Amos HM, Zhang Y, Sunderland EM, Sonke JE (2018) Modelling the mercury stable isotope distribution of Earth surface reservoirs: implications for global Hg cycling. Geochim Cosmochim Acta 246:156–173CrossRefGoogle Scholar
  46. Tang S, Wang L, Feng X, Feng Z, Li R, Fan H, Li K (2016) Actual mercury speciation and mercury discharges from coal-fired power plants in Inner Mongolia, Northern China. Fuel 180:194–204CrossRefGoogle Scholar
  47. Tang S, Feng C, Feng X, Zhu J, Sun R, Fan H, Wang L, Li R, Mao T, Zhou T (2017) Stable isotope composition of mercury forms in flue gases from a typical coal-fired power plant, Inner Mongolia, northern China. J Hazard Mater 328:90–97CrossRefGoogle Scholar
  48. Wang S, Zhang L, Li G, Wu Y, Hao J, Pirrone N, Sprovieri F, Ancora MP (2010) Mercury emission and speciation of coal-fired power plants in China. Atmos Chem Phys 10:1183–1192CrossRefGoogle Scholar
  49. Wang Z, Chen J, Feng X, Hintelmann H, Yuan S, Cai H, Huang Q, Wang S, Wang F (2015) Mass-dependent and mass-independent fractionation of mercury isotopes in precipitation from Guiyang, SW China. C R Geosci 347:358–367CrossRefGoogle Scholar
  50. Wiederhold JG, Cramer CJ, Daniel K, Infante I, Bourdon B, Kretzschmar R (2010) Equilibrium mercury isotope fractionation between dissolved Hg(II) species and thiol-bound Hg. Environ Sci Technol 44:4191–4197CrossRefGoogle Scholar
  51. Wiederhold JG, Smith RS, Siebner H, Jew AD, Brown GE, Bourdon B, Kretzschmar R (2013) Mercury isotope signatures as tracers for Hg cycling at the new Idria Hg mine. Environ Sci Technol 47:6137–6145CrossRefGoogle Scholar
  52. Xu H, Sonke JE, Guinot B, Fu X, Sun R, Lanzanova A, Candaudap F, Shen Z, Cao J (2017) Seasonal and annual variations in atmospheric Hg and Pb Isotopes in Xi’an, China. Environ Sci Technol 51:3759–3766CrossRefGoogle Scholar
  53. Xu H, Sun R, Cao J, Huang R, Guinot B, Shen Z, Jiskra M, Li C, Du B, He C, Liu S, Zhang T, Sonke JE (2019) Mercury stable isotope compositions of Chinese urban fine particulates in winter haze days: implications for Hg sources and transformations. Chem Geol. CrossRefGoogle Scholar
  54. Yamakawa A, Moriya K, Yoshinaga J (2017) Determination of isotopic composition of atmospheric mercury in urban-industrial and coastal regions of Chiba, Japan, using cold vapor multicollector inductively coupled plasma mass spectrometry. Chem Geol 448:84–92CrossRefGoogle Scholar
  55. Yin R, Feng X, Wang J, Bao Z, Yu B, Chen J (2013) Mercury isotope variations between bioavailable mercury fractions and total mercury in mercury contaminated soil in Wanshan Mercury Mine, SW China. Chem Geol 336:80–86CrossRefGoogle Scholar
  56. Yin R, Feng X, Li X, Yu B, Du B (2014) Trends and advances in mercury stable isotopes as a geochemical tracer. Trends Environ Anal Chem 2:1–10CrossRefGoogle Scholar
  57. Yu B, Fu X, Yin R, Zhang H, Wang X, Lin C, Wu C, Zhang Y, He N, Fu P, Wang Z, Shang L, Sommar J, Sonke JE, Maurice L, Guinot B, Feng X (2016) Isotopic composition of atmospheric mercury in China: new evidence for sources and transformation processes in air and in vegetation. Environ Sci Technol 50:9262–9269CrossRefGoogle Scholar
  58. Yuan S, Zhang Y, Chen J, Kang S, Zhang J, Feng X, Cai H, Wang Z, Wang Z, Huang Q (2015) Large variation of mercury isotope composition during a single precipitation event at Lhasa City, Tibetan Plateau, China. Proc Earth Planet Sci 13:282–286CrossRefGoogle Scholar
  59. Yuan S, Chen J, Cai H, Yuan W, Wang Z, Huang Q, Liu Y, Wu X (2018) Sequential samples reveal significant variation of mercury isotope ratios during single rainfall events. Sci Total Environ 624:133–144CrossRefGoogle Scholar
  60. Zambardi T, Sonke JE, Toutain JP, Sortino F, Shinohara H (2009) Mercury emissions and stable isotopic compositions at Vulcano Island (Italy). Earth Planet Sci Lett 277:236–243CrossRefGoogle Scholar
  61. Zheng W, Hintelmann H (2009) Mercury isotope fractionation during photoreduction in natural water is controlled by its Hg/DOC ratio. Geochim Cosmochim Acta 73:6704–6715CrossRefGoogle Scholar
  62. Zheng W, Hintelmann H (2010) Nuclear field shift effect in isotope fractionation of mercury during abiotic reduction in the absence of light. J Phys Chem A 114:4238–4245CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Institute of Surface-Earth System SciencesTianjin UniversityTianjinChina

Personalised recommendations