Standard Methods: 4500-CN-F: Cyanide in Water by Ion Selective Electrode
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Official Method Name
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Test Method F. Cyanide-Selective Electrode |
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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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Ion Selective Electrode |
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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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Cyanide in the alkaline distillate from the preliminary treatment procedures can be determined potentiometrically by using a cyanide-selective electrode in combination with a double-junction reference electrode and a pH meter having an expanded millivolt scale, or a specific ion meter. |
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Scope and Application
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This method is applicable to surface waters, treated and untreated wastewaters, and industrial wastes. |
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Applicable Concentration Range
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0.05 to 10 mg cyanide/L |
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Interferences
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All known interferences eliminated or reduced by distillation |
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Quality Control Requirements
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None given |
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Sample Handling
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Add 0.1 g sodium arsenite in the presence of oxidizing agents. Add lead acetate or lead carbonate in the presence of sulfide. Filter sample before raising pH for stabilization. If samples cannot be anlayzed immediately, add NaOH pellets or a strong NaOH solution to raise sample pH to 12 to 12.5. Store in a closed, dark bottle in a cool place. |
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Maximum Holding Time
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24 hours after raising pH to > 12 |
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Relative Cost
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Less than $50 |
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Sample Preparation Methods
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