Anions in estuary and coastal waters - Determination of Anions in Natural and Treated Waters - page 426

4.6 Multianion analysis
4.6.1 Spectrophotometric method, sulphate, phosphate and nitrate
Airey et al. [8] have described a method for removing sulphide prior to the determination
of the above anions in anoxic estuarine waters. Mercury(II) chloride was used to
precipitate free sulphide from samples of anoxic water. The sulphide-free supernatant
was used to estimate sulphide by measuring the concentration of unreacted mercury(II),
as well as to determine sulphate, inorganic phosphate and nitrate by spectrophotometric
methods, in which sulphide interferes. Sulphide concentrations in the range 0.5-
180,000L −1 sulphur could be measured, while the lower limits for sulphate, ammonia,
nitrite and inorganic phosphate were respectively 0.024, −1.0 and 1µg L −1 .
4.7 Sulphide
4.7.1 Spectrophotometric method
See section 4.6.1.1.
References
1 Brown, L. and Bellinger, E.L. Water Research , 223 , 12 (1978).
2 Petts, K.W. Water Research Centre, Medmenham Laboratory UK. Technical Report TR
120. The determination of oxidised nitrogen and nitrite in estuarine waters by
autoanalysis. June (1979).
3 Crompton, T.R. Unpublished work.
4 Itoh, K., Nakayama, M., Chikuma, M. and Tanaka, H. Fresenius Zeitschrift für
Analytische Chemie , 321 , 56 (1985).
5 Bode, H. Fresenius Zeitschrift für Analytische Chemie , 143 , 182 (1954).
6 Ohta, K. and Suzuki, M. Fresenius Zeitschrift für Analytische Chemie , 302 , 177
(1980).
7 Cheam, V. and Agemian, H. Analytica Chimica Acta , 113 , 237 (1980).
8 Airey, D., Dal Pont, G. and Sanders, G. Analytica Chimica Acta , 106 , 79 (1984).