| Autor: |
W.Y Huang, H Louie, Frank Krikowa, Tailuan Nguyen, William A. Maher, D Wruck |
| Rok vydání: |
2002 |
| Předmět: |
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| Zdroj: |
Analytica Chimica Acta. 463:283-293 |
| ISSN: |
0003-2670 |
| DOI: |
10.1016/s0003-2670(02)00346-x |
| Popis: |
The evaluation of the use of alkaline peroxodisulfate digestion with low pressure microwave, autoclave or hot water bath heating for the determination of total phosphorus and nitrogen in turbid lake and river waters is described. The efficiency of these digestion procedures were compared to a Kjeldahl digestion procedure with sulphuric acid–potassium sulfate and copper sulfate. The final solution before digestion was 0.045 M in potassium peroxodisulfate and 0.04 M in sodium hydroxide. Procedures were evaluated by the analysis of suspensions of two reference materials, National Institute of Environmental Science, Japan, no. 3 Chlorella and no. 2 pond sediment and natural turbid waters. Best recoveries of phosphorus and nitrogen by microwave heating were obtained when solutions were digested at 95 ◦ C for 40 min. Quantitative recoveries of phosphorus from Chlorella suspensions up to 1000 mg/l were obtained by all three heating procedures, but incomplete recoveries of nitrogen occurred above 20 mg N/l in the digested sample. Good recoveries of phosphorus and nitrogen from suspended sediment suspensions were obtained only from solutions containing 150 mg/l) and are only suitable for the analysis of very turbid samples when the turbidity is due to organic matter (algal cells, plant detritus). Underestimation of nitrogen occurs when samples contain more than 20 mg N/l. © 2002 Elsevier Science B.V. All rights reserved. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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