Skip to main content

Organic Acids for the In Situ Remediation of Soils Polluted by Heavy Metals: Soil Flushing in Columns

Abstract

To compare the soil remediation effectiveness of saltsof weak organic acids with strongchelating agents, three soils of different textures,all polluted by heavy metals, were washed in a column,at optimum pH, with salts of weak organic acids,namely, citrate, tartarate or oxalate + citrate orchelating agents (EDTA or DTPA). For the clay loam,Cr, Mn, Hg and Pb were removed by citrate andtartarate at levels of 43 to 45, 37 to 41, 91 to 92and 75%, respectively. EDTA and DTPA effectivelyleached only Pb after 20 pore volumes. For the loam,citrate leached 98 and 89% of Cd and Pb after 20 porevolumes, respectively, while tartarate leached out 91and 87% of Cd and Pb. EDTA and DTPA removed 93 to97% of these metals after 20 pore volumes. For thesandy clay loam, 84 to 91, 73 to 84, 56 to 70 and 72to 81% of Cd, Cu, Pb and Zn were removedrespectively, by citrate and tartarate. EDTA and DTPAremoved 93 to 97% of these metals after 20 porevolumes. An in situ soil remediation simulation wasalso tested using the sandy clay loam in a tub. After12 hr of retention, the citrate solution washed 81, 82,73 and 90%, of Cd, Cu, Pb and Zn, respectively, aftersix pore volumes. EDTA and DTPA effectively removedall heavy metals, except for Hg, but also extractedlarge quantities of soil nutrients and pollute thesoil by being adsorbed on the soil particles. Thesalts of citrate and tartarate effectively removed theheavy metals from the three polluted soils whileleaching little macro-nutrients and improving soilstructure. Each soil reached C and B levels ofsoil-clean-up criteria after 10 to 20 pore volumes andwithin 10 to 15 hr of flushing.

This is a preview of subscription content, access via your institution.

References

  • Bell, C. F.: 1977, Principles and Applications of Metal Chelation, Clarendon Press, Oxford.

    Google Scholar 

  • Bourg, A. C. M.: 1988, ‘Metals in Aquatic and Terrestrial Systems: Sorption, Speciation and Mobilization’, in Salomons, W. and Forstner, U. (eds.), Chemistry and Biology of Solid Waste, Springer-Verlag, New York, pp. 2–32.

    Google Scholar 

  • Burckhard, S. R., Schwab, A. P. and Banks, M. K.: 1995, J. Hazardous Materials 41, 135.

    Google Scholar 

  • Czupyrna, G., Levy, R. D., MacLean, A. I. and Gold, H.: 1989, In situ Immobilization of Heavy Metals-Contaminated Soils, Noyed Data Corp., Park Ridge, New Jersey, U.S.A.

    Google Scholar 

  • Davis, A. P. and Singh, I.: 1995, J. Environ. Eng. 121(2), 174.

    Google Scholar 

  • Liu, D. K. and Dezfulian, H.: 1995, ‘Characterization and Remediation of Soils Contaminated with Copper’, in Acar, Y. B. and Daniel, D. E. (eds.), 2000 Geoenvironment, American Society of Civil Engineers, New Orleans, Louisiana, U.S.A., Geotechnical Special Publication No. 46, Vol. 1, pp. 228–241.

    Google Scholar 

  • MEFQ: 1994, Ten Years of Restoration of Contaminated Sites, Ministry of Environment and Wild Life, Quebec City, Canada.

    Google Scholar 

  • Reed, B. E., Carriere, P. C. and Moore, R. E.: 1996, J. Environ. Eng. 122(1), 48.

    Google Scholar 

  • SAS: 1990, User's Guide Version 6, 1st ed. SAS Institute Inc., ASA Circle Box 8000, Cary, NC 27512–8000, U.S.A.

    Google Scholar 

  • Tan, K. H.: 1986, ‘Degradation of Soil Minerals by Organic Acids’, in Huang, P. M. and Schnitzer, M.(eds.), Interactions of SoilMinerals with Natural and Microbes, Soil Science Society of America, Special Publication No. 17, Madison, Wisconsin, U.S.A., pp. 1–27.

    Google Scholar 

  • Wasay, S. A., Barrington, S. F. and Tokunaga, S.: 1998a, J. Soil Contamination 7(1), 103.

    Google Scholar 

  • Wasay, S. A., Barrington, S. F. and Tokunaga, S.: 1998b, Can. Agri. Eng. 40(1), 9.

    Google Scholar 

  • Wasay, S. A., Barrington, S. F. and Tokunaga, S.: 1998c, Environ. Technol. 19, 369.

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Wasay, S.A., Barrington, S. & Tokunaga, S. Organic Acids for the In Situ Remediation of Soils Polluted by Heavy Metals: Soil Flushing in Columns. Water, Air, & Soil Pollution 127, 301–314 (2001). https://doi.org/10.1023/A:1005251915165

Download citation

  • Issue Date:

  • DOI: https://doi.org/10.1023/A:1005251915165

  • chelating agents
  • columns
  • heavy metal
  • salts of organic acids
  • soil flushing
  • soil pollution