The term "cyanide" generally refers to one of three classifications of
cyanide, which are: (1) total cyanide; (2) weak acid dissociable (WAD) cyanide; and (3) free cyanide, as shown in the following figure. Each of these forms of cyanide has specific analytical methodologies for its measurement, and it is important that the relationship between these forms be understood when analyzing cyanide-containing solutions. As indicated in this figure, for a given solution the total cyanide level is always greater than or equal to the WAD cyanide level, and likewise, the WAD cyanide level is always greater than or equal to the free cyanide concentration.
General Classification of Cyanide Compounds
An approach to assessing the quality of water samples in many situations is to analyze for WAD cyanide since this includes the toxicologically and environmentally important forms of cyanide, including free cyanide and moderately and weakly complexed metal-cyanides. Total cyanide includes free cyanide, WAD cyanide plus the relatively non-toxic iron-cyanide complexes. Complete characterization of a cyanide solution generally includes analyses for pH, total cyanide, WAD cyanide, thiocyanate, cyanate, ammonia, nitrate and base metals such as copper, iron, nickel and zinc. Click to learn more about the cyanide related compounds thiocyanate, cyanate, ammonia and nitrate.
A companion document to the draft International Cyanide Management Code deals
with the collection and analysis of cyanide samples and is a useful reference.
Download Now (44 kB)
Online cyanide analyzers are also being used to continuously monitor
cyanide levels in processing plants. Click on the following links
for related information.
Process Analytical Systems (553 kB)
Mintek Cyanoprobe (144 kB)
Cyantific Instruments P/L
(72 kB)
There are several step-by-step laboratory procedures for analyzing cyanide, and below are links to some of the more common methods. Right click on the Adobe Acrobat icon and select "Save Target As..." to save the file onto your computer.
| Method |
Description |
Download |
USEPA OIA-1677 |
Available Cyanide by Flow Injection with Ligand Exchange
Click here to download
brochure describing OI Analytical equipment. |
 (415 kB) |
USEPA 9010B |
Total and Amenable Cyanide: Distillation |
(79 kB) |
USEPA 9010C |
Total and Amenable Cyanide: Distillation |
(123 kB) |
USEPA 9012A |
Total and Amenable Cyanide
(Automated Colorimetric With
Off-Line Distillation) |
(110 kB)
|
USEPA 9012B |
Total and Amenable Cyanide
(Automated Colorimetric With
Off-Line Distillation) |
(270 kB)
|
USEPA 9013 |
Cyanide Extraction Procedure for Solids and Oils |
(158 kB)
|
USEPA 9014 |
Titrimetric and Manual Spectrophotometric Determinative Methods for Cyanide |
(73 kB)
|
USEPA 9213 |
Potentiometric Determination of Cyanide in Aqueous Samples and Distillates
with Ion-Selective Electrode |
(66 kB)
|
USEPA 335.1 |
Cyanides, Amenable
to Chlorination |
(16 kB)
|
USEPA 335.2 |
Cyanide, Total (Titrimetric
and Spectrophotometric) |
(95 kB)
|
USEPA 335.3 |
Cyanide, Total
(Colorimetric and Automated UV) |
(37 kB)
|
USEPA 335.4 |
Determination of Total Cyanide by Semi-Automated Colorimetry |
(199 kB)
|
|
ASTM D2036-06
|
D2036-98 Standard Test Methods for Cyanides in Water |
ASTM
|
ASTM D4282-02 |
D4282-02 Standard Test Method for Determination of Free Cyanide in Water and Wastewater by Microdiffusion |
ASTM
|
|
ASTM D4374-06
|
D4374-00 Standard Test Methods for Cyanides in Water--Automated Methods for
Total Cyanide, Acid dissociable Cyanide, and Thiocyanate |
ASTM
|
|
ASTM D6696-05e1
|
D6696-01 Standard Guide for Understanding Cyanide Species |
ASTM
|
ASTM D6888-03 |
D6888-03 Standard Test Method for Available Cyanide with Ligand Displacement and Flow Injection Analysis (FIA) Utilizing Gas Diffusion Separation and Amperometric Detection |
ASTM
|
Standard Methods
4500-CN |
Methods for Total Cyanide, Cyanides Amenable to Chlorination, WAD Cyanide,
Cyanogen Chloride, Cyanates and Thiocyanate |
Standard Methods |
ISO 6703-1,2 |
Determination of Total
and Easily Liberatable Cyanide |
ISO
|
|
ISO/CD 27368
|
Analysis of cyanide in blood
|
ISO
|
| USGS I-1300 |
Cyanide,
Colorimetric, Pyridine-Pyrazolone |
(111 kB)
|
| USGS I-2302 |
Cyanide,
Colorimetric, Barbituric Acid, Automated-Segmented Flow |
(79 kB)
|
| USGS I-3300 |
Cyanide,
Colorimetric, Pyridine-Pyrazolone |
(37 kB) |
| USGS I-4302 |
Cyanide,
Colorimetric, Barbituric Acid, Automated-Segmented Flow |
(79 kB)
|
| USGS I-6302 |
Cyanide,
Colorimetric, Barbituric Acid, Automated-Segmented Flow |
(79 kB)
|
|
