EPA-NERL: 258.1: Potassium by Flame AA
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Official Method Name
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Potassium (Atomic Absorption, Direct Aspiration) |
|---|---|
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Current Revision
| Issued 1971; Editorial Revision 1974 |
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Media
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WATER |
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Instrumentation
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Flame Atomic Absorption |
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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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A sample prepared according to EPA Method 200.0 is analyzed using a flame atomic absorption spectrometer. Specifications for instrument operation and preparation of standards are provided in the method. |
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Scope and Application
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This method determines potassium by flame atomic absorption spectrometry. Sample pretreatment according to EPA Method 200.0 determines the applicability. |
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Applicable Concentration Range
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0.1 - 2.0 mg/L (optimal range); 0.04 mg/L (sensitivity). |
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Interferences
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For interferences see EPA Method 200.0. In air-acetylene or other high temperature flames, potassium can experience partial ionization which indirectly affects absorption sensitivity. The presence of other alkali salts may reduce this ionization. The addition of cesium may should be considered for more stringent control of ionization. |
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Quality Control Requirements
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QC requirements for drinking water procedures are provided in method 200.0 |
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Sample Handling
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Sample handling and preservation procedures are provided in EPA Method 200.0. If suspended solids are present in significant amounts to clog the nebulizer, the sample may be allowed to settle and the supernatant liquid analyzed directly. |
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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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200.0 |
