Standard Methods: 3030 I: Nitric, Perchloric and Hydrofluoric Acid
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Official Method Name
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Nitric Acid-Perchloric Acid-Hydrofluoric Acid Digestion of Samples |
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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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Sampling/Preparation |
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Method Source
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Citation
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Brief Method Summary
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When using more than 100 mL of sample during digestion, determine recovery for each matrix to verify method validity. Bring well-mixed sample to a slow boil, and evaporate to 15-20 mL. Add 12 mL of concentrated HNO3, and evaporate to near dryness. Repeat HNO3 addition and evaporation. Cool and add 20 mL HClO4 and 1 mL HF. Boil until solution is clear and white fumes of HClO4 first appear. Cool and add 50 mL water. Filter if needed. Pour filtrate and washings in volumetric flask. Dilute to 100 mL mark, and mix. Remove aliquots or concentrate sample (see abstract in Method 3030-D) for analysis. Samples totally digested by acid digestion techniques yield comparable precision and bias, however, the minimal amount of acid should be used in the digestion as acid adds metals to the sample. |
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Scope and Application
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This method is applicable to the digestion of metals in waste and wastewater samples. |
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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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