ASTM RR-D19-1193 2015
D7237-Test Method for Free Cyanide and Aquatic Free Cyanide with Flow Injection Analysis (FIA) Utilizing Gas Diffusion Separation and Amperometric Detection

Standard No.

ASTM RR-D19-1193 2015

Release Date

1970

Published By

/

Scope

1.1 This test method is used to establish the concentration of free cyanide in an aqueous wastewater,, effluent and in-stream free cyanide concentrations after mixing treated water with receiving water. The test conditions of this method are used to measure free cyanide (HCN and CN) and cyanide bound in the metal-cyanide complexes that are easily dissociated into free cyanide ions at the pH of 6. Free cyanide is determined at pH 6 at room temperature. The aquatic free cyanide can be determined by matching the pH to the water in the receiving environment in the range of pH 6 to 8. The extent of HCN formation is less dependent on temperature than the pH; however, the temperature can be regulated if deemed necessary for aquatic free cyanide to further simulate the actual aquatic environment. 1.2 The free cyanide method is based on the same instrumentation and technology that is described in standard test method D6888, but employs milder conditions (pH 6-8 buffer versus HCl or H2SO4 in the reagent stream), and does not utilize ligand displacement reagents. 1.3 The aquatic free cyanide measured by this procedure should be similar to actual levels of HCN in the original aquatic environment. This in turn may give a reliable index of toxicity to aquatic organisms. 1.4 This procedure is applicable over a range of approximately 2 to 500 g/L (parts per billion) free cyanide. Sample dilution may increase cyanide recoveries depending on the cyanide speciation; therefore, it is not recommended to dilute samples. Higher concentrations can be analyzed by increasing the range of calibration standards or with a lower injection volume. In accordance with Guide E1763 and Practice D6512 the lower scope limit was determined to be 9 g/L for chlorinated gold leaching barren effluent water and X µg/L in the mixed treated waste water sample matrix. 1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 6This test method is under the jurisdiction of ASTM Committee D19 on Water and is the direct responsibility of Subcommittee D19.06 on Methods for Analysis for Organic Substances in Water. Current edition approved May 1, 2010. Published June 2010. Originally approved in 2006. Last previous edition approved in 2006 as D7237 – 06. DOI: 10.1520/D7237-10. RR: D19-1193 1.6 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 8.6 and Section 9.

ASTM RR-D19-1193 2015 Referenced Document

• ASTM D1129 Standard Terminology Relating to Water*， 1999-04-20 Update
• ASTM D1193 Standard Specification for Reagent Water*， 1999-04-20 Update
• ASTM D1293 Standard Test Methods for pH of Water*， 1999-04-20 Update
• ASTM D2036 Standard Test Methods for Cyanides in Water*， 1998-04-20 Update
• ASTM D2777 Standard Practice for Determination of Precision and Bias of Applicable Methods of Committee D-19 on Water*， 1998-04-20 Update
• ASTM D3856 Standard Guide for Good Laboratory Practices in Laboratories Engaged in Sampling and Analysis of Water*， 1995-04-20 Update
• ASTM D4841 Standard Practice for Estimation of Holding Time for Water Samples Containing Organic and Inorganic Constituents*， 2018-10-15 Update
• ASTM D5847 Standard Practice for Writing Quality Control Specifications for Standard Test Methods for Water Analysis*， 1999-04-20 Update
• ASTM D6512 Standard Practice for Interlaboratory Quantitation Estimate*， 2024-04-20 Update
• ASTM D6696 Standard Guide for Understanding Cyanide Species*， 2023-11-15 Update
• ASTM D6888 Standard Test Method for Available Cyanides with Ligand Displacement and Flow Injection Analysis (FIA) Utilizing Gas Diffusion Separation and Amperometric Detection*， 2023-11-15 Update
• ASTM D7365 Standard Practice for Sampling, Preservation and Mitigating Interferences in Water Samples for Analysis of Cyanide*， 2022-05-01 Update
• ASTM E1763 Standard Guide for Interpretation and Use of Results from Interlaboratory Testing of Chemical Analysis Methods*， 1998-04-20 Update
• ASTM E691 Standard Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method*， 1999-04-20 Update