Flow-injection spectrofluorimetric determination of sulphate using calcein and zirconium

✍ Scribed by N. Chimpalee; D. Chimpalee; S. Suparuknari; B. Boonyanitchayakul; D.Thorburn Burns

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 386 KB
• Volume: 298
• Category: Article
• ISSN: 0003-2670
• DOI: 10.1016/0003-2670(94)00298-3

✦ Synopsis

Sulphate can be determined spectrofluorimetrically (A,, = 505 nm, A,, = 410 nm) based on the formation of a ternary complex between sulphate, zirconium and calcein in a flow-injection system. The carrier stream was deionised water and the reagent streams were 100 pg ml _ ' Zr (as ZrOCl,) in 1% (v/v> hydrochloric acid, and 40 pg ml-' calcein in 0.1 M potassium hydroxide. The injection rate was 50 h-'. The calibration graph was linear up to 25 pg ml-' SOi-based on 250-~1 injection volumes. The relative standard deviation (n = 10) was 1.95% for 10 pg ml-' SO:-; the detection limit was 0.82 pg ml-' SO:-. The system has been applied to the determination of sulphur in NIST coal samples after oxygen bomb combustion.