Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10560944 | Talanta | 2005 | 5 Pages |
Abstract
A flow-injection procedure for spectrophotometric determination of sulphate in soil solutions is proposed. Samples are directly soaked from the soils under field conditions, in-line filtered through ceramic plates, and preserved with thymol. The method involves reaction with barium dimethylsulphonazo(III) (DMSA) in the presence of dimethylsulphoxide (DMSO) with further measuring the decrease in absorbance at 668 nm. A linear response is observed up to about 5 mgl â1 SO4, and detection limit (3Ï criterion) is 0.1 mg lâ1 SO4. Only 4.5 μg DMSA is consumed per determination. The system is rugged and baseline drift is not observed during extended operation periods. About 60 samples are injected per hour, and the results are precise (r.s.d. <2%) and in agreement with ion chromatography.
Related Topics
Physical Sciences and Engineering
Chemistry
Analytical Chemistry
Authors
Silvia R.P. Meneses, Nelson Maniasso, Elias A.G. Zagatto,