Journal of Applied Electrochemistry

, Volume 33, Issue 1, pp 61–71 | Cite as

Chemical and electrochemical considerations on the removal process of hexavalent chromium from aqueous media

  • C. Barrera-DíazEmail author
  • M. Palomar-Pardavé
  • M. Romero-Romo
  • S. Martínez


Two methods were used to remove Cr(VI) from industrial wastewater. Although both are based in the same general reaction: 3Fe(II)(aq) + Cr(VI)(aq) ⇌; 3Fe(III)(aq) + Cr(III)(aq) the way in which the required amount of Fe(II) is added to the wastewater is different for each method. In the chemical method, Fe(II)(aq) is supplied by dissolving FeSO4 · 7(H2O)(s) into the wastewater, while in the electrochemical process Fe(II)(aq) ions are formed directly in solution by anodic dissolution of an steel electrode. After this reduction process, the resulting Cr(III)(aq) and Fe(III)(aq) ions are precipitated as insoluble hydroxide species, in both cases, changing the pH (i.e., adding Ca(OH)2(s)). Based on the chemical and thermodynamic characteristics of the systems Cr(VI)–Cr(III)–H2O–e and Fe(III)–Fe(II)–H2O–e both processes were optimized. However we show that the electrochemical option, apart from providing a better form of control, generates significantly less sludge as compared with the chemical process. Furthermore, it is also shown that sludge ageing promotes the formation of soluble polynuclear species of Cr(III). Therefore, it is recommended to separate the chromium and iron-bearing phases once they are formed. We propose the optimum hydraulic conditions for the continuous reduction of Cr(VI) present in the aqueous media treated in a plug-flow reactor.

continuous Cr(VI) removal environmental processes thermodynamical analysis 


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  1. 1.
    M. Stoepler, ‘Hazardous Metals in the Environment Techniques and Instrumentation in Analytical Chemistry’ (Elsevier, New York, 1992), p. 373.Google Scholar
  2. 2.
    J. Gaulhofer and V. Biabchi, ‘Chromium. Metals and their Compounds in the Environment’ (VCH, Wheinheim, 1991), p. 30.Google Scholar
  3. 3.
    R. Cespón-Romero, M. Yebra-Biurrum and M. Bernejo-Barrera, Anal. Chim. Acta 327 (1996) 37.Google Scholar
  4. 4.
    J. Nriagu and E. Nieboer, ‘Chromium in the Natural and Human Environments’ (Wiley Series, New York, 1988), p. 82.Google Scholar
  5. 5.
    D. Golub and Y. Oren, J. Appl. Electrochem. 19 (1989) 311.Google Scholar
  6. 6.
    S. Goeringer, N.R. Tacconi, C.R. Chenthamarakshan C.R. and K. Rajeshwar, J. Appl. Electrochem. 30 (2000) 891.Google Scholar
  7. 7.
    S.E. Jardine, M.A. Fendorf, Mayes, L. Larsen, S. Brooks and W. Bailey, Environ. Sci. Technol. 33 (1999) 2939.Google Scholar
  8. 8.
    F. Colín and S. Gazbar, Wat. Res. 29 (1995) 2000.Google Scholar
  9. 9.
    S.A. Martínez, M.G. Rodrìguez and C. Barrera, Wat. Sci. Technol. 231 (2000) 65.Google Scholar
  10. 10.
    J.H. Glynn and G.W. Heinke, ‘Environmental Engineering’ (Pearson, México, 1999), chapter 12.Google Scholar
  11. 11.
    APHA, AWWA, ‘Standard Methods for the Examination of Water and Wastewater’, 19th edn (American Public Health Association, Washington DC, 1995).Google Scholar
  12. 12.
    A. Serruya, B.R. Scharifker, I. González, M.T. Oropeza and M. Palomar-Pardavé, J. Appl. Eletrochem. 26 (1996) 451.Google Scholar
  13. 13.
    M. Palomar-Pardavé, M.T. Ramírez, I. González, A. Serruya and B.R. Scharifker, J. Electrochem. Soc. 143 (1996) 1539.Google Scholar
  14. 14.
    A.B. Soto, E.M. Arce, M. Palomar-Pardavé and I. Gonza´ lez, Electrochim. Acta 41 (1996) 2647.Google Scholar
  15. 15.
    M. Palomar-Pardavé, I. González, A.B. Soto and E.M. Arce, J. Electroanal. Chem. 443 (1998) 125.Google Scholar
  16. 16.
    A. Rojas-Hernández, M.T. Ramírez, J.G. Ibáñez and I. González, J. Electrochem Soc. 138 (1991) 365.Google Scholar
  17. 17.
    A. Rojas-Hernández, M.T. Ramírez and I. Gonza´ lez, J. Chem. Ed. 72 (1995) 1099.Google Scholar
  18. 18.
    C. Baes and R. Mesmer, ‘The Hydrolysis of Cations’, 2nd edn (Robert E. Krieger, Publising, Malabar, FA 1986), p. 211.Google Scholar
  19. 19.
    W. Stumm and J. Morgan, ‘Aquatic Chemistry: Chemical Equilibria and Rates in Natural Waters’, 3rd edn (John Wiley & Sons, New York, 1996), p. 234.Google Scholar
  20. 20.
    I.J. Buerge and S.J. Stephan, Environ. Sci. Technol. 33 (1999) 4285.Google Scholar
  21. 21.
    R.R. Patterson, S. Fendorf and M. Fendorf, Environ. Sci. Technol. 31 (1997) 2039.Google Scholar
  22. 22.
    N. Kongsricharoern and C. Polprasert, Water Sci. Tech. 31 (1995) 109.Google Scholar
  23. 23.
    E.M.N. Chirwa and Y. Wang, Environ. Sci. Technol. 31 (1997) 1446.Google Scholar
  24. 24.
    J. Bard and L.R. Faulker, ‘Electrochemical Methods’ (John Wiley & Sons, New York, 1985), p. 324.Google Scholar
  25. 25.
    A. Rojas Hernández, M.T. Ramírez and I. González, Anal. Chim. Acta 278 (1993) 321.Google Scholar
  26. 26.
    A. Rojas Hernández, M.T. Ramírez and I. González, Anal. Chim. Acta 278 (1993) 335.Google Scholar
  27. 27.
    Code of Federal Regulations, Chapter I, Title 40 section 141.11 (2002).Google Scholar
  28. 28.
    SEMARNAP, NOM-001-ECOL-1996, Diario Oficial de la Federación, México (1996).Google Scholar
  29. 29.
    M.J. Avena, C.E. Giacomelli, C.D. García and C.P. De Pauli, Langmuir 12 (1996) 6659.Google Scholar
  30. 30.
    J.P. Fitts, G.E. Brown and G.A. Parks, Environ. Sci. Technol. 34 (2000) 5122.Google Scholar
  31. 31.
    X. Chen, G. Chen and P.L. Yue, Environ. Sci. Technol. 36 (2002) 778.Google Scholar
  32. 32.
    US EPA, Office of Solid Waste. ‘Regulatory Impact Analysis of the Final Rule for 180-day Accumulation Time for F006 Wastewater Treatment Sludges’. Prepared by DPRA Inc., St. Paul, (14 Jan. 2000), p. 21.Google Scholar
  33. 33.
    US EPA, Office of Solid Waste. ‘Background Documents for the Cost and Economic Impact Analysis of Listing Four Petroleum refining Wastes as Hazardous Waste under RCRA Subtitle C’. Prepared by DPRA Inc., (Jan. 1998), pp. 3–6.Google Scholar

Copyright information

© Kluwer Academic Publishers 2003

Authors and Affiliations

  • C. Barrera-Díaz
    • 1
    • 2
    Email author
  • M. Palomar-Pardavé
    • 2
  • M. Romero-Romo
    • 2
  • S. Martínez
    • 2
  1. 1.Facultad de Química, Intersección Paseos Colón y TollocanUniversidad Autónoma del Estado de MéxicoTolucaEstado de México;
  2. 2.Depto. de Energía, Área de Procesos AmbientalesUniversidad Autónoma Metropolitana-AzcapotzalcoMéxico D.FMéxico;

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