TY - JOUR
T1 - Kinetics of Thiocyanate Formation by Reaction of Cyanide and Its Iron Complexes with Thiosulfate
AU - Kurashova, Irina
AU - Kamyshny, Alexey
N1 - Funding Information:
This work was supported by the Marie Curie Actions CIG PCIG10-GA-2011-303740 (ThioCyAnOx) Grant. We are grateful to Ido Ben Laish for help with establishing experimental protocols for analyses of cyanide and sulfur species. The authors would like to thank Valeria Boyko for assistance with experiments.
Funding Information:
This work was supported by the Marie Curie Actions CIG PCIG10-GA-2011-303740 (ThioCyAnOx) Grant. We are grateful to Ido Ben Laish for help with establishing experimental protocols for analyses of cyanide and sulfur species. The authors would like to thank Valeria Boyko for assistance with experiments. Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Publisher Copyright:
© 2019, Springer Nature B.V.
PY - 2019/12/1
Y1 - 2019/12/1
N2 - Reactions between cyanide and compounds, which contain S–S bonds, in aqueous media result in formation of thiocyanate. In this work, we studied the kinetics of reactions of thiosulfate with free cyanide and its complexes under environmental conditions. Rates of reactions between cyanide species and thiosulfate decrease in the following order: CN− > HCN > [Fe(CN)6]3− > [Fe(CN)6]4−. However, at neutral and slightly acidic pH range, reaction of thiosulfate with iron-cyanide complexes outcompetes its reaction with free cyanide, which exists in equilibrium with complexed cyanide. At environmentally relevant conditions, the characteristic time of reaction between free cyanide and thiosulfate was found to be tens of thousands of years, while for iron-cyanide complexes it was found to be hundreds to millions of years. Examples of application of kinetic parameters for calculation of rates of cyanide consumption in industrial (coke oven wastewater) and non-polluted natural aquatic system (Delaware Great Marsh) are provided.
AB - Reactions between cyanide and compounds, which contain S–S bonds, in aqueous media result in formation of thiocyanate. In this work, we studied the kinetics of reactions of thiosulfate with free cyanide and its complexes under environmental conditions. Rates of reactions between cyanide species and thiosulfate decrease in the following order: CN− > HCN > [Fe(CN)6]3− > [Fe(CN)6]4−. However, at neutral and slightly acidic pH range, reaction of thiosulfate with iron-cyanide complexes outcompetes its reaction with free cyanide, which exists in equilibrium with complexed cyanide. At environmentally relevant conditions, the characteristic time of reaction between free cyanide and thiosulfate was found to be tens of thousands of years, while for iron-cyanide complexes it was found to be hundreds to millions of years. Examples of application of kinetic parameters for calculation of rates of cyanide consumption in industrial (coke oven wastewater) and non-polluted natural aquatic system (Delaware Great Marsh) are provided.
KW - Cyanide
KW - Hexacyanoferrate(II)
KW - Hexacyanoferrate(III)
KW - Sulfide oxidation intermediates
KW - Thiocyanate
KW - Thiosulfate
UR - http://www.scopus.com/inward/record.url?scp=85074932456&partnerID=8YFLogxK
U2 - 10.1007/s10498-019-09361-y
DO - 10.1007/s10498-019-09361-y
M3 - Article
AN - SCOPUS:85074932456
SN - 1380-6165
VL - 25
SP - 219
EP - 236
JO - Aquatic Geochemistry
JF - Aquatic Geochemistry
IS - 5-6
ER -