Continuous flow analysis of iron (III) in seawater using a chalcogenide glass ion-selective electrode

✍ Scribed by Roland De Marco; Bobby Pejcic; Xue Dong Wang

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 119 KB
• Volume: 11
• Category: Article
• ISSN: 0895-7533
• DOI: 10.1002/(sici)1098-2728(1999)11:5<284::aid-lra7>3.0.co;2-8

✦ Synopsis

Continuous flow analysis (CFA) is suitable for rapid and reliable determination of free Fe III in organic-free, UV-oxidized seawater when used in conjunction with an extrapolation method that predicts the steady-state potentials of an Fe III chalcogenide glass ion-selective electrode (ISE) by using initial data associated with a step-wise change in aFe ‫ם3‬ . It is shown that the CFA technique yields a Nernstian response of a 30 mV per decade change in aFe ‫ם3‬ in saline citrate buffers in the range of 10 ‫22מ‬ to 10 ‫61מ‬ M Fe ‫ם3‬ . Validation of the CFA technique in organicfree, UV-oxidized seawater has demonstrated that the response of the Fe III ISE is internally consistent with the well-known inorganic speciation equilibria occurring in natural seawater.