View PDF Version
 
DOI: 10.1039/A701801K (Paper) Reference Section for: Anal. Commun., 1997, 34, 147-151

Sequential Injection Acid–Base Titration—A Useful Application for Process Analytical Science

(Note: The full text of this document is currently only available in the PDF Version )

Jacobus F. van Staden and Hanneli du Plessis

Abstract

A sequential injection (SI) titration system is proposed for the titration of a strong acid with a strong base. The concept is based on the sequential injection of a base titrant, acid analyte and a base titrant zone into a distilled water carrier stream, giving a stack of well-defined zones adjacent to each other in a holding coil, which is swept by reversal through a reaction coil to the detector. The base zones contain Bromothymol Blue as indicator and the endpoint is monitored spectrophotometrically at 620 nm. A linear relationship between peak width and logarithm of acid concentration is obtained in the range 0.01 to 0.1 mol l-1 of HCl with 1 × 10-3 mol l-1 of NaOH as titrant. Other linear ranges are possible by changing the titrant concentrations. The results obtained for the sequential injection titration of samples is in good agreement with a standard potentiometric method with an RSD <0.30%. The system is fully computerised with a sample frequency of 30 samples h-1.

References

  1. J. Růžička, E. H. Hansen and H. Mosbaek, Anal. Chim. Acta, 1977, 92, 235 CrossRef CAS.
  2. A. U. Ramsing, J. Růžička and E. H. Hansen, Anal. Chim. Acta, 1981, 129, 1 CrossRef CAS.
  3. D. R. Turner, S. Knox and M. Whitfield, Anal. Proc., 1987, 24, 360 Search PubMed.
  4. J. F. Tyson, Anal. Proc., 1987, 24, 362 Search PubMed.
  5. J. Toei, Fresenius' Z. Anal. Chem., 1988, 330, 484 Search PubMed.
  6. G. Nagy, Z. Feher, K. Toth, E. Pungor and A. Ivaska, Talanta, 1979, 26, 1143 CrossRef CAS.
  7. Z. Fehér, I. Kolbe and E. Pungor, Analyst, 1991, 116, 483 RSC.
  8. B. Fuhrmann and U. Spohn, Anal. Chim. Acta, 1993, 282, 397 CrossRef CAS.
  9. K. G. Schick, Adv. Instrum., 1984, 39, 279 Search PubMed.
  10. N. Ishibashi and T. Imato, Fresenius'Z. Anal. Chem., 1986, 323, 244 Search PubMed.
  11. J. F. Van Staden, Water SA, 1986, 12, 93 Search PubMed.
  12. T. Imato, A. Katafuchi, T. Hamazoe, J. Yagi, K. Takahara and N. Ishibashi, Anal. Sci., 1989, 5, 777 CAS.
  13. R. H. Taylor, J. Růžička and G. D. Christian, Talanta, 1992, 39, 285 CrossRef CAS.
  14. R. H. Taylor, C. Winbo, G. D. Christian and J. Růžička, Talanta, 1992, 39, 789 CrossRef CAS.
  15. J. Růžička and G. D. Marshall, Anal. Chim. Acta, 1990, 237, 329 CrossRef CAS.
  16. J. Růžička, G. D. Marshall and G. D. Christian, Anal. Chem., 1990, 62, 1861 CrossRef CAS.
  17. J. Růžička and T. Gübeli, Anal. Chem., 1991, 63, 1680 CrossRef CAS.
  18. T. Gübeli, G. D. Christian and J. Růžička, Anal. Chem., 1991, 63, 2407 CrossRef CAS.
  19. J. Růžička and E. H. Hansen, Flow Injection Analysis, Wiley, New York, 1981 Search PubMed.
  20. E. H. Hansen, Fresenius' Z. Anal. Chem., 1988, 329, 656 Search PubMed.
  21. G. D. Marshall and J. F. van Staden, Anal. Instrum., 1992, 20, 79 Search PubMed.
  22. G. D. Marshall and J. F. van Staden, Process Control Qual., 1992, 3, 251 CAS.
Click here to see how this site uses Cookies. View our privacy policy here.