A Comparison of Commonly Used Cyanide Analytical Methodologies for Manufactured Gas Plant (MGP) Applications

Abstract

In this article, the authors report on the analysis of a groundwater sample from an area that has been impacted by cyanide-containing residuals. Several common analytical procedures were used to illustrate and compare the concentrations of cyanide that the various methodologies were able to detect. Replicates of each analysis were run for comparison. In addition, filtered and unfiltered sample aliquots were analyzed to evaluate whether significant differences could be observed with any of the analytical methods that could be attributed to relative solubility differences among the cyanide species present. Special emphasis is placed on the usefulness of the data for manufactured gas plants (MGP) site project applications. The current work opens the gate for future studies into environmental forensic applications of cyanide source identification based on the comparison of the differing analytical methodologies.

Keywords:

• MGP
• cyanide
• laboratory analyses
• manufactured gas plant
• environmental chemistry
• cyanide toxicity

Acknowledgments

The authors wish to thank Danuta Drewczynska for her most valuable efforts, without which this study could not have been performed.

Notes

*Due to the insoluble nature of ferric ferrocyanide, 8.6 mg of solid was added directly to the distillation flask.

*0.858 mg/L total;

**, assumes % recovery of the K₄Fe(CN)₆ complex only; Rep, replicate sample; TC, total cyanide; PAC, physiologically available cyanide; WADC, weak acid dissociable cyanide; AC, amenable cyanide; FC, free cyanide.

*, 8.6 mg/absolute. Due to the insoluble nature of ferric ferrocyanide, 8.6 mg of solid was added directly to the distillation flask.

*, amenable cyanide.