EPA-NERL: 376.2: Sulfide by Colorimetry
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Official Method Name
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Sulfide (Colorimetric, Methylene Blue) |
|---|---|
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Current Revision
| Issued 1978 |
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Media
|
WATER |
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Instrumentation
|
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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Sulfide in a sample reacts with dimethyl-p-phenylenediamine (p-aminodimethyl aniline) in the presence of ferric chloride to produce methylene blue, a dye which is measured with a colorimeter. |
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Scope and Application
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This method determines total and dissolved sulfides in drinking, surface and saline waters; domestic and industrial wastes. |
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Applicable Concentration Range
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Sulfide concentrations below 20 mg/L. |
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Interferences
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(A) Aeration: Aeration can result in loss of sulfide due to volatilization or reaction with oxygen.(B) Color/Turbidity: Color or turbidity in the sample may interfere with the measurements. |
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Quality Control Requirements
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None. |
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Sample Handling
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Analyze immediately. |
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Maximum Holding Time
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Analyze immediately. |
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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. |
