EPA-NERL: 365.4: Phosphorus by Automated Colorimetry
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Official Method Name
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Phosphorus, Total (Colorimetric, Automated, Block Digestor AA II) |
|---|---|
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Current Revision
| Issued 1974 |
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Media
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WATER |
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Instrumentation
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Spectroscopy (Colorimetry; Photometry) |
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Method Subcategory
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Inorganic |
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Method Source
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Citation
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Brief Method Summary
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The sample is heated in the presence of sulfuric acid, potassium sulfate, and mercuric sulfate for two and one half hours. The residue is cooled and diluted to 25 mL and placed in autoanalyzer for determination of phosphorus by colorimetry. |
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Scope and Application
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This method determines total phosphorus in drinking water, surface water; domestic and industrial wastes. |
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Applicable Concentration Range
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0.01 to 20 mg P/L |
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Interferences
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None provided. |
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Quality Control Requirements
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None. |
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Sample Handling
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Samples should be collected in plastic or Pyrex glass containers. Samples should be preserved with 2 mL of concentrated sulfuric acid and refrigerated at 4oC. |
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Maximum Holding Time
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48 hours (orthophosphate, dissolved) 28 days (Hydrolyzable and Total) 24 hours (Total Dissolved). (MCAWW, Table 1). |
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Relative Cost
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Less than $50 |
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Sample Preparation Methods
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None. |
