ASTM: D6071: Sodium by GFAA
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Official Method Name
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Standard Test Method for Low Level Sodium in High Purity Water by Graphite Furnace Atomic Absorption Spectroscopy |
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Current Revision
| Reapproved 2000. Current edition approved Dec. 10, 1996. Published March 1997. |
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Media
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WATER |
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Instrumentation
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Graphite Furnace-Atomic Absorption Spectrometer |
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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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Sodium is determined by atomic absorption utilizing a graphite furnace for sample atomization. A sample volume of several microlitres, depending upon the concentration of the analyte, is deposited on a graphite tube housed within an electrical furnace, and the system is heated in an inert gas environment. The sample is evaporated to dryness, ashed (charred or pyrolyzed), and atomized. Ground-state atoms are produced during the atomization stage of the temperature program. The ground-state atoms absorb the energy at a specific wavelength produced from a source as they are bombarded by the energy. The amount of energy absorbed is proportional to the concentration of the analyte in the sample. The absorption signal produced during atomization is recorded on a chart recorder or stored in microprocessor memory and compared to those standards taken through the same process by means of an analytical curve. |
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Scope and Application
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This test method covers the determination of trace sodium in high purity water. |
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Applicable Concentration Range
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1-40 ug/L |
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Interferences
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No known interferences from other constituents are found in high purity waters. Sodium is a common contaminant in many reagents. The analyst must ensure that the quality of the reagent used in the procedure is sufficiently high to determine trace levels of sodium. Airborne particulates are a potential interference with the analysis of sodium by GFAAS. |
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Quality Control Requirements
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Sample Handling
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Collect the sample in accordance with Practices D 1066 and D 3370 or Specification D 1192. Samples should be collected in polystyrene, TFE-fluorocarbon or polypropylene bottles only. Do not use glass or polyethylene containers. The containers should be rinsed with Type I water. The container should be stored prior to use by either air drying and capping or filling with Type I water and capping. For further details, see Practice D 4453. To avoid the possibility of contamination, samples should not be acidified. |
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Maximum Holding Time
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Relative Cost
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Unknown |
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Sample Preparation Methods
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