Chemical Papers

, Volume 60, Issue 4, pp 283–287 | Cite as

Application of a ternary complex of tungsten(VI) with 4-nitrocatechol and thiazolyl blue for extraction-spectrophotometric determination of tungsten

  • V. D. Lekova
  • K. B. GavazovEmail author
  • A. N. Dimitrov


A new ternary ion-association complex of tungsten(VI), 4-nitrocatechol (NC), and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (Thiazolyl Blue, MTT) was obtained and studied using an extraction-spectrophotometric method. The optimum pH, reagent concentrations, and extraction time were determined. The composition of the complex was found to be W(VI): NC: MTT = 1: 2: 2. The extraction process was investigated quantitatively and the key constants were calculated. The molar absorptivity of the chloroform extract at λmax = 415 nm was 2.8 × 104 dm3 mol−1 cm−1, and the Beer’s law was obeyed up to 8.8 μg cm−3 tungsten(IV). The limit of detection and limit of quantification were calculated to be 0.27 μg cm−3 and 0.92 μg cm−3, respectively. The effect of foreign ions and reagents was studied and a competitive method for determination of tungsten in products from ferrous metallurgy was developed. The residual standard deviation and the relative error were 0.53 % and 0.2 %, respectively.


tungsten(VI) extraction spectrophotometric determination ternary complex 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    Busev, A. I., Ivanov, V. M., and Sokolova, T. A., Analiticheskaya khimiya volframa. (Analytical Chemistry of Tungsten.) Nauka, Moscow, 1976.Google Scholar
  2. 2.
    Pilipenko, A. T. and Tananayko, M. M., Raznoligandnye i raznometallnye kompleksy i ikh primenenie v analiticheskoy khimii. (Different-Ligand and Different-Metal Complexes and their Use in Analytical Chemistry.) Khimiya, Moscow, 1983.Google Scholar
  3. 3.
    Nazarenko, V. A., Poluektova, E. N., and Shitareva, G. G., Zh. Anal. Khim. 28, 101 (1973).Google Scholar
  4. 4.
    Dimitrov, A., Alexandrov, A., Dimova, A., and Vrchlabský, M., Scr. Fac. Sci. Nat. Univ. Purk. Brun. 13, 117 (1983).Google Scholar
  5. 5.
    Dimitrov, A., Alexandrov, A., Hrdlička, A., and Vrchlabský, M., Scr. Fac. Sci. Nat. Univ. Purk. Brun. 14, 91 (1984).Google Scholar
  6. 6.
    Alexandrov, A., Dimitrov, A., Patcheva, A., and Vrchlabský, M., Scr. Fac. Sci. Nat. Univ. Purk. Brun. 15, 497 (1985).Google Scholar
  7. 7.
    Dimitrov, A. and Alexandrov, A., Anal. Lab. 4, 172 (1995).Google Scholar
  8. 8.
    Simeonova, Zh., Gavazov, K., and Alexandrov, A., Anal. Lab. 7, 184 (1998).Google Scholar
  9. 9.
    Dimitrov, A. and Kostova, S., Bulg. Chem. Ind. 70, 88 (1999).Google Scholar
  10. 10.
    Kostova, S., Dimitrov, A., and Alexandrov, A., Chem. Pap. 54, 66 (2000).Google Scholar
  11. 11.
    Gavazov, K., Simeonova, Zh., and Alexandrov, A., Zh. Neorg. Khim. 45, 142 (2000).Google Scholar
  12. 12.
    Gavazov, K., Simeonova, Zh., and Alexandrov, A., Talanta 52, 539 (2000).CrossRefGoogle Scholar
  13. 13.
    Gavazov, K., Simeonova, Zh., and Alexandrov, A., Zh. Neorg. Khim. 46, 494 (2001).Google Scholar
  14. 14.
    Dimitrov, A., Kostova, S., Pancheva, J., and Lekova, V., Bulg. Chem. Ind. 73, 20 (2002).Google Scholar
  15. 15.
    Dimitrov, A., Lekova, V., Gavazov, K., and Boyanov, B., Cent. Eur. J. Chem. 3, 747 (2005).CrossRefGoogle Scholar
  16. 16.
    Poluektova, E. N. and Shitareva, G. G., Zh. Anal. Khim. 27, 1301 (1972).Google Scholar
  17. 17.
    Natansohn, S., Krugler, J. I., Lester, J. E., Chagnon, M. S., and Finocchiaro, R. S., J. Phys. Chem. 84, 2972 (1980).CrossRefGoogle Scholar
  18. 18.
    Nazarenko, V. A. and Poluektova, E. N., Zh. Neorg. Khim. 14, 204 (1969).Google Scholar
  19. 19.
    Jander, G. and Krüecke, V., Z. Anorg. Allg. Chem. 265, 244 (1951).CrossRefGoogle Scholar
  20. 20.
    Sasaki, J., Acta Chem. Scand. 15, 175 (1961).CrossRefGoogle Scholar
  21. 21.
    Bartušek, M., Collect. Czech. Chem. Commun. 38, 2255 (1973).Google Scholar
  22. 22.
    Fikr, J., Thesis. Purkyně University, Brno, 1964.Google Scholar
  23. 23.
    Bulatov, M. I. and Kalinkin, I. P., Prakticheskoe rukovodstvo po fotokolorimetricheskim i spectrofotometricheskim metodam analyza. (Practical Manual on Photocolorimetric and Spectrophotometric Methods of Analysis.) Khimiya, Leningrad, 1986.Google Scholar
  24. 24.
    Likussar, W. and Boltz, D., Anal. Chem. 43, 1265 (1971).CrossRefGoogle Scholar
  25. 25.
    Fogg, A. G., Marriott, D. K., and Thorburn Burns, D., Analyst 95, 854 (1970).CrossRefGoogle Scholar
  26. 26.
    Eberle, A. R., Anal. Chem. 35, 669 (1963).CrossRefGoogle Scholar
  27. 27.
    Zharovskii, F. G. and Gorina, D. O., Zh. Anal. Khim. 26, 766 (1971).Google Scholar
  28. 28.
    Chaprasova, L. P., Inoyatov, A., and Arzyntseva, L. G., Ind. Lab. 52, 1080 (1986).Google Scholar
  29. 29.
    Masti, S. P., Seetharamappa, J., and Melwanki, M. B., Anal. Sci. 18, 913 (2002).PubMedCrossRefGoogle Scholar

Copyright information

© Institute of Chemistry, Slovak Academy of Sciences 2006

Authors and Affiliations

  • V. D. Lekova
    • 1
  • K. B. Gavazov
    • 1
    Email author
  • A. N. Dimitrov
    • 1
  1. 1.Department of General and Inorganic ChemistryPlovdiv UniversityPlovdivBulgaria

Personalised recommendations