Standard Methods: 4500-Cl- E: Chloride by Automated Ferricyanide Method
|
Official Method Name
|
4500-Cl- E. Automated Ferricyanide Method |
|---|---|
|
Current Revision
| Standard Methods Online |
|
Media
|
WATER |
|
Instrumentation
|
Automated Spectrophotometer |
|
Method Subcategory
|
Inorganic |
|
Method Source
|
|
|
Citation
|
|
|
Brief Method Summary
|
Thiocyanate ion is liberated from mercuric thiocyanate by the formation of soluble mercuric chloride. In the presence of ferric ion, free thiocyanate ion forms a highly colored ferric thiocyanate, of which the intensity is proportional to the chloride concentration. |
|
Scope and Application
|
The method is applicable to potable, surface, and saline waters, and domestic and industrial wastewaters. |
|
Applicable Concentration Range
|
1 to 200 mg Cl-/L |
|
Interferences
|
Remove particulate matter by filtration or centrifugation before analysis. Guard against contamination from reagents, water, glassware, and sample preservation process. No chemical interferences are significant. |
|
Quality Control Requirements
|
See Section 4020 Quality Assurance/Quality Control. |
|
Sample Handling
|
Collect representative samples in clean, chemically resistant glass or plastic bottles. The maximum sample portion required is 100 mL. No special preservative is necessary if the sample is to be stored. |
|
Maximum Holding Time
|
28 days (regulatory); See Section 1060 |
|
Relative Cost
|
Less than $50 |
|
Sample Preparation Methods
|
