DOE: MU012R: Cyanide by Microdistillation and Argento
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Official Method Name
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Determination of Total Cyanide by Remote Microdistillation and Argentometric Titration |
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Current Revision
| 1997 |
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Media
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OTHER |
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Instrumentation
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Titration |
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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 is pretreated with ethylenediamine and acid to ensure complete dissolution of acid-insoluble alkali nickel ferrocyanide compounds. The samples are distilled for 30 minutes using a Lachat MICRODIST disposable distillation tube. Cyanide is released from most of its complexes and converted to hydrogen cyanide (HCN) by treatment with acid in the presence of magnesium ions. The HCN gas from the sample is trapped in an alkaline absorber solution. The concentration of cyanide in the absorber solution is determined using a silver nitrate titration with a rhodamine indicator. |
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Scope and Application
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This method determines total cyanide in radioactive waste tank matrices when the total cyanide is greater than approximately 0.1% by weight (concentrations greater than 1 g CN-/kg). |
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Applicable Concentration Range
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None given. |
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Interferences
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(A) Cobalticyanide: Cobalticyanide is not determined using the distillation procedure. (B) Nitrate/Nitrite: Nitrate/Nitrite can react with certain organic compounds to form HCN gas during distillation. (C) Aldehydes: Aldhydes convert to cyanohydrins, which convert to HCN during distillation. |
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Quality Control Requirements
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one blank, MS, duplicate, spiked blank/control per analytical session |
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Sample Handling
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In general, radioactive waste tank samples need no preservation. Once samples have been treated with pretreatment solution, however, the distillation should be performed as soon as possible (i.e., within a few days). Distillates should be analyzed within two week of their generation. |
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Maximum Holding Time
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Relative Cost
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Less than $50 |
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Sample Preparation Methods
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