Standard Methods: 3030D: Preliminary Digestion for Metals
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Official Method Name
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Preliminary Digestion of Sludge for Metals Analysis |
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Current Revision
| Standard Methods Online |
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Media
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WATER |
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Instrumentation
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Preparatory Procedure |
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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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To determine metals by atomic absorption (AA) or inductively-coupled plasma (ICP) spectroscopy, samples must be digested to reduce organic matter and to convert metals to a particular form. Transfer 1 g of well-mixed sludge with 15 percent total solids to a preweighed digestion vessel. Reweigh the sample and vessel. Digest sample with one of the digestion techniques explained in Method abstracts 3030-E through -K. If the sample volume used for digestion is too great for the vessel capacity, add sample as evaporation proceeds. Report results on a wet or dry weight basis. |
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Scope and Application
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This method is applicable to the preliminary treatment of metal samples by digestion. |
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Applicable Concentration Range
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Interferences
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Metals introduced during preliminary treatment from equipment common to environmental labs. |
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Quality Control Requirements
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Check reagent grade acids for purity. Process blanks through all digestion and filtration steps. |
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Sample Handling
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Collect sample in plastic or glass container which has been rinsed with 1+1 HNO3. Adjust the pH of the sample to < 2 with HNO3. For dissolved metals, filter samples immediately. Analyze within 6 months. |
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Maximum Holding Time
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6 months |
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Relative Cost
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Less than $50 |
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Sample Preparation Methods
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