EPA-NERL: 212.3: Boron by Colorimetry
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Official Method Name
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Boron (Colorimetric, Curcumin) |
|---|---|
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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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When a sample of water containing boron is acidified and evaporated in the presence of curcumin, a red-colored product called rosocyanine is formed. The rosocyanine is taken up in a suitable solvent, and the red color (which is proportional to colorimetry) is compared with standards photometrically. |
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Scope and Application
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This method determines boron in drinking waters, surface waters, domestic and industrial wastes. |
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Applicable Concentration Range
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0.1-1.0 mg/L (optimal range). |
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Interferences
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(A) Nitrate: Nitrate above 20 mg/L can interfere. (B) Hardness: Hardness above 100 mg/L can interfere. Passing the sample through a cation exchange resin eliminates this problem. |
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Quality Control Requirements
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None. |
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Sample Handling
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Maximum Holding Time
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6 months (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. |
