1. Scope

1.1 This method is used to determine the concentration of available inorganic cyanide in an aqueous wastewater or effluent. The method detects the cyanides that are free (HCN and CN ^- ) and metal-cyanide complexes that are easily dissociated into free cyanide ions. The method does not detect the less toxic strong metal-cyanide complexes, cyanides that are not 'amenable to chlorination.'

1.2 Total cyanide can be determined for samples that have been distilled as described in Test Methods D 2036, Test Method A, Total Cyanides after Distillation. The cyanide complexes are dissociated and absorbed into the sodium hydroxide capture solution, which can be analyzed with this test method; therefore, ligand exchange reagents from sections 8.12 and 8.13 would not be required when determining total cyanide after distillation.

1.3 This procedure is applicable over a range of approximately 2 to 400 ?g/L (parts per billion) available cyanide. Higher concentrations can be analyzed by dilution or lower injection volume.

1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific hazard statements are given in Note 2 and Section 9.

2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

ASTM Standards

D1129 Terminology Relating to Water

D1193 Specification for Reagent Water

D2036 Test Methods for Cyanides in Water

D2777 Practice for Determination of Precision and Bias of Applicable Test Methods of Committee D19 on Water

D3856 Guide for Management Systems in Laboratories Engaged in Analysis of Water

D4375 Practice for Basic Statistics in Committee D19 on Water

D5847 Practice for Writing Quality Control Specifications for Standard Test Methods for Water Analysis

D6696 Guide for Understanding Cyanide Species

D7365 Practice for Sampling, Preservation and Mitigating Interferences in Water Samples for Analysis of Cyanide

E60 Practice for Analysis of Metals, Ores, and Related Materials by Spectrophotometry

E275 Practice for Describing and Measuring Performance of Ultraviolet and Visible Spectrophotometers

Keywords

amperometry; available cyanide; cyanide; cyanide amenable to chlorination; flow injection analysis; free cyanide; gas diffusion membrane; ligand exchange; silver electrode; weak acid dissociable cyanide; Amperometric titration; Cyanides; Flow injection analysis (FIA); Free cyanide; Gas diffusion; Ligand displacement; Pervaporation (PV); Weak acid-dissociable (WAD) cyanide ;

ICS Code

ICS Number Code 17.120.10 (Flow in closed conduits)

DOI: 10.1520/D6888-04

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