Standard Methods: 5310B: Total organic carbon by High-Temperature Combustion
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Official Method Name
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High-Temperature Combustion Method |
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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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Total Organic Carbon Analyzer |
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Method Subcategory
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Organic |
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Method Source
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Citation
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Brief Method Summary
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The sample is homogenized and diluted as necessary and a microportion is injected into a heated reaction chamber packed with an oxidative catalyst such as cobalt oxide, platinum group metals, or barium chromate. The water is vaporized and the organic carbon and inorganic carbon is oxidized to CO2 and H2O. The CO2 is transported in the carrier-gas stream and is measured by means of a nondispersive IR analyzer, or titrated coulometrically. |
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Scope and Application
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This method covers the determination of total organic carbon in surface waters, domestic and industrial wastes. |
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Applicable Concentration Range
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None given |
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Interferences
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Removal of carbonate and bicarbonate by acidification and purging with purified gas results in the loss of volatile organic substances. |
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Quality Control Requirements
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After every tenth analysis, analyze a blank and a laboratory conyrol sample prepared from a source of material other than the calibration standards, at a level similar to the analytical samples. Preferably prepare the laboratory control sample in a matrix similar to that of the samples. Alternatively, periodically make known additions to samples to ensure recovery from unknown matrices. |
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Sample Handling
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If possible, rinse bottles with sample before filling and carry field blanks through sampling procedure to check for any contamination that may occur. Collect and store samples in glass bottles protected from sunlight and seal with TFE-backed septa. Before use, wash bottles with acid, seal with aluminum foil, and bake at 400oC for at least 1 h. Wash uncleaned TFE septa with detergent, rinse repeatedly with organic-free water, wrap in aluminum foil, and bake at 100oC for 1 h. If a sample contains gross particulates or insoluble matter, homogenize until satisfactory replication is obtained. Analyze a homogenizing blank consisting of reagent water carried through the homogenizing treatment. If dissolved organic carbon is to be determined, filter sample and reagent water blank through 0.45-um filter. If inorganic carbon must be removed before analysis, transfer a representative portion (10 to 15 mL) to a 30-mL beaker, add acid to reduce pH to 2 or less, and purge with gas for 10 min. |
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Maximum Holding Time
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7 days. Analyze immediately, or refrigerate and add HCl, H3PO4, or H2SO4 to pH < 2 |
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Relative Cost
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$51 to $200 |
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Sample Preparation Methods
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