Water, Air, & Soil Pollution

, 229:359 | Cite as

Immobilization of Boron and Arsenic in Alkaline Coal Fly Ash through an Aging Process with Water and Elucidation of the Immobilization Mechanism

  • Yasumasa Ogawa
  • Kento Sakakibara
  • Tsugumi Seki
  • Chihiro Inoue


We previously reported that a simple treatment—addition of only small amounts of water to coal fly ash (CFA) to form CFA paste followed by aging for 1–4 weeks—is advantageous for the immobilization of highly soluble B, F, Cr, and As. In this study, we investigated the leachability of Ca, SO4, B, and As over time from non-aged and aged CFA samples to elucidate a possible immobilization mechanism. For this purpose, two types of CFA samples, one showing effective immobilization of B and As by water addition and aging (sample A) and the other showing less or no immobilization (sample B), were examined. Calcium and SO4, B, and As in non-aged sample A dissolved immediately after the start of the leaching test, indicating that these elements existed in highly soluble particles. After the rapid dissolution, their concentrations in the leachate gradually increased, possibly due to the dissolution of glassy phases. During the 1-week leaching test, the B and As concentrations in the leachate finally decreased. The addition of only small amounts of water to CFA (Sample A) for aging produce both alkaline and supersaturation conditions for the formation of several types of Ca-bearing secondary minerals such as calcite and ettringite, which are formed under alkaline conditions. Boron and As originally existing as highly soluble particles in CFA are expected to be incorporated into and/or sorbed on these secondary minerals as water-insoluble phases. Compared to non-aged CFA, their leachability from the aged sample A remained lower throughout the entire leaching test. Possibly due to these secondary minerals being formed on the CFA surface, B and As dissolutions associated with glassy phases are also prevented. In contrast, the pH of the leachate from CFA (sample B) at the beginning of the leaching test was acidic and then abruptly became alkaline. This means that water-soluble particles that can produce acidic conditions are also contained in these alkaline CFAs. Dissolution of these substances during aging makes it difficult to generate alkaline conditions in the CFA paste. Consequently, the formation of secondary minerals and the concomitant immobilization of toxic elements are prevented.


Coal fly ash Boron Arsenic Leaching Immobilization 



The authors thank to Taiheiyo Cement Co. Ltd. for analyzing the chemical compositions of coal fly ash samples. This manuscript was greatly improved by the valuable comments from two anonymous reviewers.

Supplementary material

11270_2018_3997_MOESM1_ESM.docx (263 kb)
ESM 1 (DOCX 262 kb)


  1. Ahmaruzzaman, M. (2010). A review on the utilization of fly ash. Progress in Energy and Combustion Science, 36, 327–363.CrossRefGoogle Scholar
  2. Baba, A., Gurdal, G., Sengunalp, F., & Ozay, O. (2008). Effects of leachant temperature and pH on leachability of metals from fly ash: case study: can thermal power plant, province of Canakkale, Turkey. Environmental Monitoring and Assessment, 139, 287–298.CrossRefGoogle Scholar
  3. Baba, A., Gurdal, G., & Şengünalp, F. (2010). Leaching characteristics of fly ash from fluidized bed combustion thermal power plant: case study: Çan (Çanakkale-Turkey). Fuel Processing Technology, 91, 1073–1080.CrossRefGoogle Scholar
  4. Banerjee, S. S., Jayaram, R.,. V., & Joshi, M. V. (2003). Removal of Nickel(II) and Zinc(II) from wastewater using fly ash and impregnated fly ash. Separation Science and Technology, 38, 1015–1032.CrossRefGoogle Scholar
  5. Banerjee, S. S., Joshi, M. V., & Jayaram, R. V. (2005). Removal of Cr(VI) and Hg(II) from aqueous solutions using fly ash and impregnated fly ash. Separation Science and Technology, 39, 1611–1629.CrossRefGoogle Scholar
  6. Blissett, R. S., & Rowson, N. A. (2009). A review of the multi-componemt utilization of coal fly ash. Fuel, 97, 1–23.CrossRefGoogle Scholar
  7. Bothe, J. M., & Brown, P. W. (1998). Phase formation in the system CaO–Al2O3–B2O3–H2O at 23±1°C. Journal of Hazardous Materials, B63, 199–210.CrossRefGoogle Scholar
  8. Cox, J. A., Lundquist, G. L., Przyjazny, A., & Schmulbach, C. D. (1978). Leaching of boron from coal ash. Environmental Science & Technology, 12, 722–723.CrossRefGoogle Scholar
  9. van der Hoek, E. E., Bonouvrie, P. A., & Comans, R. N. J. (1994). Sorption of As and Se on mineral components of fly ash: relevance for leaching processes. Applied Geochemistry, 9, 403–412.CrossRefGoogle Scholar
  10. Diamadopoulos, E., Ioannidis, S., & Sakellaropoulos, G. P. (1993). As(V) removal from aqueous solutions by fly ash. Water Research, 27, 1773–1777.CrossRefGoogle Scholar
  11. Dutta, B. K., Khanra, S., & Mallic, D. (2009). Leaching of elements from coal fly ash: Assessment of its potential for use in filling abandoned coal mines. Fuel, 88, 1314–1323.CrossRefGoogle Scholar
  12. Gabrisova, A., Havlica, J., & Sahu, S. (1991). Stability of calcium sulphoaluminate hydrates in water solutions with various pH values. Cement and Concrete Research, 21, 1023–1027.CrossRefGoogle Scholar
  13. Harkness, J. S., Sulkin, B., & Vengosh, A. (2016). Evidence for coal ash ponds leaking in the southeastern United States. Environmental Science & Technology, 50, 6583–6592.CrossRefGoogle Scholar
  14. Hassett, D. J. (1994). Scientifically valid leaching of coal conversion solid residues to predict environmental impact. Fuel Processing Technology, 39, 445–459.CrossRefGoogle Scholar
  15. Hassett, D. J., Pflughoeft-Hassett, D. F., & Heebink, L. V. (2003). Leaching of CCB’S: over 25 years of research. In proceedings of the international ash utilisation symposium. Kentucky: University of Kentucky.Google Scholar
  16. Hiraga, Y., & Shigemoto, N. (2010). Boron uptake behavior during ettringite synthesis in the presence of H3BO3 and in a suspension of ettringite in H3BO3. Journal of Chemical Engineering of Japan, 43, 865–871.CrossRefGoogle Scholar
  17. Hollis, F. J., Keren, R., & Gal, M. (1986). Boron release and sorption by fly ash as affected by pH and particle size. Journal of Environmental Quality, 17, 181–184.CrossRefGoogle Scholar
  18. Iwashita, A., Sakaguchi, Y., Nakajima, T., Takanashi, H., Ohki, A., & Kambara, S. (2005). Leaching characteristics of boron and selenium for various coal fly ashes. Fuel, 84, 479–485.CrossRefGoogle Scholar
  19. Izquierdo, M., & Querol, X. (2012). Leaching behavior of elements from coal combustion fly ash: an overview. International Journal of Coal Geology, 94, 54–66.CrossRefGoogle Scholar
  20. Jankowski, J., Ward, C. R., French, D., & Groves, S. (2006). Mobility of trace elements from selected Australian fly ashes and its potential impact on aquatic ecosystems. Fuel, 85, 243–256.CrossRefGoogle Scholar
  21. Komonweeraket, K., Cetin, B., Benson, C. H., Aydilek, A. H., & Edil, T. B. (2015). Leaching characteristics of toxic constituents from coal fly ash mixed soils under the influence of pH. Waste Management, 38, 174–194.CrossRefGoogle Scholar
  22. Lecuyer, I., Bicocchi, S., Ausset, P., & Lefevre, R. (1996). Physico-chemical characterization and leaching of desulphurization coal fly ash. Waste Management & Research, 14, 15–28.CrossRefGoogle Scholar
  23. Lemly, A. D. (2015). Damage cost of the Dan River coal ash spill. Environmental Pollution, 197, 55–61.CrossRefGoogle Scholar
  24. Liu, X., Zhao, X., Yin, H., Chen, J., & Zhang, N. (2017). Intermediate-calcium based cementitious materials prepared by MSWI fly ash and other solid wastes: hydration characteristics and heavy metals solidification behavior. Journal of Hazardous Materials, 349, 262–271.CrossRefGoogle Scholar
  25. Luhl, R., Vengosh, A., Dwyer, G., Hsu-Kim, H., & Deonarine, A. (2010). Environmental impacts of the coal ash spill in Kingston, Tennessee: an 18-month survey. Environmental Science & Technology, 44, 9272–9278.CrossRefGoogle Scholar
  26. Neupane, G., & Donahoe, R. J. (2013). Leachability of elements in alkaline and acidic coal fly ash samples during batch and column leaching tests. Fuel, 104, 758–770.CrossRefGoogle Scholar
  27. Ogawa, Y., Sakakibara, K., Suto, K., & Inoue, C. (2014). Immobilization of B, F, Cr, and As in alkaline coal fly ash through an aging process with water. Environmental Monitoring and Assessment, 186, 6757–6770.CrossRefGoogle Scholar
  28. Öztürk, N., & Kavak, K. (2005). Adsorption of boron from aqueous solutions using fly ash: batch and column studies. Journal of Hazardous Materials, 127, 81–88.CrossRefGoogle Scholar
  29. Polat, H., Vengosh, A., Pankratov, I., & Polat, M. (2004). A new methodology for removal of boron from water by coal and fly ash. Desalination, 164, 173–188.CrossRefGoogle Scholar
  30. Polowczyk, I., Ulatowska, J., Koźlecki, T., Bastrzyk, A., & Sawiński, W. (2013). Studies on removal of boron from aqueous solution by fly ash agglomerates. Desalination, 310, 93–101.CrossRefGoogle Scholar
  31. Polowczyk, I., Bastrzyk, A., Ulatowska, J., Szczałba, E., Koźlecki, T., & Sadowski, Z. (2016). Influence of pH on arsenic(III) removal by fly ash. Separation Science and Technology, 51, 2612–2619.CrossRefGoogle Scholar
  32. Sheng, G., Li, Q., & Zhai, J. (2012). Investigation on the hydration of CFBC fly ash. Fuel, 98, 61–66.CrossRefGoogle Scholar
  33. Solem-Tishmack, J. K., McCarthy, G. J., Docktor, B., Eylands, K. E., Thompson, J. S., & Hassett, D. J. (1995). High-calcium coal combustion by-products: engineering properties, ettringite formation, and potential application in solidification and stabilization of selenium and boron. Cement and Concrete Research, 25, 658–670.CrossRefGoogle Scholar
  34. Tessier, A., Campbell, P. G. C., & Bisson, M. (1979). Sequential extraction procedure for the speciation of particulate trace metals. Analytical Chemistry, 51, 844–851.CrossRefGoogle Scholar
  35. Zhang, M., & Reardon, E. J. (2003). Removal of B, Cr, Mo, and Se from wastewater by incorporation into hydrocalumite and ettringite. Environmental Science & Technology, 37, 2947–2952.CrossRefGoogle Scholar
  36. Zhao, S., Chen, Z., Shen, J., Kang, J., Zhang, J., & Shen, Y. (2017). Leaching mechanism of constituents from fly ash under influence of humic acid. Journal of Hazardous Materials, 321, 647–660.CrossRefGoogle Scholar

Copyright information

© Springer Nature Switzerland AG 2018

Authors and Affiliations

  • Yasumasa Ogawa
    • 1
  • Kento Sakakibara
    • 2
  • Tsugumi Seki
    • 2
  • Chihiro Inoue
    • 2
  1. 1.Faculty of International Resource SciencesAkita UniversityAkitaJapan
  2. 2.Graduate School of Environmental StudiesTohoku UniversitySendaiJapan

Personalised recommendations