On-line gas-diffusion separation and fluorimetric detection for the determination of acid dissociable cyanide

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Esther Miralles and Dolors Prat


Abstract

A flow injection system with gas diffusion separation and spectrofluorimetric detection is described for the determination of acid dissociable cyanide in waters. Cyanide diffuses through a microporous PTFE membrane from an acidic donor stream into a sodium hydroxide acceptor stream. The cyanide transferred reacts with o-phthalaldehyde and glycine to form a highly fluorescent isoindole derivative. Complete recovery of cyanide was found for Zn(CN)42, Cu(CN)32, Cd(CN)42, Hg(CN)42, Hg(CN)2 and Ag(CN)2 complexes and low recovery from Ni(CN)42. No recovery was obtained from the species that are considered as non-free cyanide producing, viz., Fe(CN)64, Fe(CN)63 and Co(CN)63. The sampling frequency was 10 h1 and the detection limit was 0.5 µg l1. The method tolerates a 40-fold excess of sulfide. The results of cyanide determination in water samples obtained with the proposed method are consistent with those obtained with APHA Method 4500 CN I for weak acid dissociable cyanide.


References

  1. E. B. Milosavljevic, L. Solujic and J. L. Hendrix, Environ. Sci. Technol., 1995, 29, 426 CAS.
  2. Z. Zhu and Z. Fang, Anal. Chim. Acta, 1987, 198, 25 CrossRef CAS.
  3. J. R. Sebroski and R. H. Ode, Environ. Sci. Technol., 1997, 31, 52 CrossRef CAS.
  4. W. E. van der Linden, Anal. Chim. Acta, 1983, 151, 359 CrossRef CAS.
  5. V. Kubán, Anal. Chim. Acta, 1992, 259, 45 CrossRef CAS.
  6. D. Christmann, C. Renn and R. Berman, Int. Lab., 1993, 23(8), 23 Search PubMed.
  7. Y. Liu, R. D. Rocklin, R. J. Joyce and M. J. Doyle, Anal. Chem., 1990, 62, 766 CrossRef CAS.
  8. Standard Methods for the Examination of Water and Wastewater, ed. Clesceri, L. S., Greenberg, A. E., and Trussell, R. R., American Public Health Association, Washington, DC, 17th edn., 1989 Search PubMed.
  9. J. C. Wilmot, L. Solujic, E. B. Milosavljevic, J. L. Hendrix and W. S. Rader, Analyst, 1996, 121, 799 RSC.
  10. E. Miralles, D. Prat, R. Compañó and M. Granados, Analyst, 1997, 122, 553 RSC.
  11. E. Figuerola, A. Florido, M. Aguilar and J. de Pablo, Anal. Chim. Acta, 1988, 215, 277 CrossRef CAS.
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