Hach Co.: 8012: Aluminum in water by Aluminon Indicator
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Official Method Name
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Aluminum By Aluminon Indicator |
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Current Revision
| 2003 |
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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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Aluminon indicator combines with aluminum in the sample to form a red-orange indicator. The intensity of color is proportional to the aluminum concentration. Ascorbic acid is added to remove iron interference. Aluminum ion (AL3+) is measured at 522 nm. |
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Scope and Application
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For water and wastewater |
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Applicable Concentration Range
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0.008-0.800 mg/L |
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Interferences
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Acidity, alkalinity, fluoride, iron, fluoride, iron, phosphate, and polyphosphate. See full method for interference removal procedures and interference levels. |
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Quality Control Requirements
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Digestion is required for determining total Al.
The sample temperature must be between 20-25 degrees C for accurate results. Clean all glassware with 6.0 N HCl and deionized water before use to remove contaminants from the glass. Wipe the outside of sample cells before each insertion into the instrument cell holder. Use a damp towel followed by a dry one to remove fingerprints or other marks. Clean the graduated cylinder and sample cells with soap and a brush immediately following the test. |
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Sample Handling
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Collect samples in clean plastic or glass bottles. Fill completely and cap tightly. Avoid agitation and prolonged exposure to air. Samples should be analyzed as soon as possible after collection but can be stored at least 24 hours by cooling to 4 deg. C or below. Warm to room temperature before analyzing. Before analysis, adjust the pH to 3.5-4.5 with sodium hydroxide. |
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Maximum Holding Time
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6 months at room temperature |
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Relative Cost
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Less than $50 |
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Sample Preparation Methods
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