Tags

Type your tag names separated by a space and hit enter

Iron(VI) and iron(V) oxidation of copper(I) cyanide.
Environ Sci Technol. 2005 May 15; 39(10):3849-54.ES

Abstract

Copper(Il) cyanide (Cu(CN)4(3-)) in the gold mine industry presentsthe biggest concern in cyanide management because it is much more stable than free cyanide. Cu(CN)4(3-) is highlytoxic to aquatic life; therefore, environmentally friendly techniques are required for the removal of Cu(CN)4(3-) from gold mine effluent. The oxidation of Cu(CN)4(3-) by iron-(VI) (FeVIO4(2-), Fe(VI)) and iron(V) (FeVO4(3-), Fe(V)) was studied using stopped-flow and premix pulse radiolysis techniques. The stoichiometry with Fe(VI) was determined to be 5HFeO(4-) + Cu(CN)4(3-) + 8H2O - > 5Fe(OH)3 + Cu2+ + 4CNO- +3/202 + 6OH-. The rate law for the oxidation of Cu(CN)4(3-) by Fe(VI) was found to be first-order with each reactant. The rates decreased with increasing pH and were mostly related to a decrease in concentration of reactive protonated Fe(VI) species, HFeO4-. A mechanism is proposed that agrees with the observed reaction stoichiometry and rate law. The rate constant for the oxidation of Cu(CN)4(3-) by Fe(V) was determined at pH 12.0 as 1.35 +/- 0.02 x 10(7) M(-1) s(-1), which is approximately 3 orders of magnitude larger than Fe(VI). Results indicate that Fe(VI) is highly efficient for removal of cyanides in gold mill effluent.

Authors+Show Affiliations

Chemistry Department, Florida Institute of Technology, 150 West University Boulevard, Melbourne, Florida 32901, USA. vsharma@fit.eduNo affiliation info availableNo affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article
Research Support, U.S. Gov't, Non-P.H.S.

Language

eng

PubMed ID

15952395

Citation

Sharma, Virender K., et al. "Iron(VI) and iron(V) Oxidation of copper(I) Cyanide." Environmental Science & Technology, vol. 39, no. 10, 2005, pp. 3849-54.
Sharma VK, Burnett CR, Yngard RA, et al. Iron(VI) and iron(V) oxidation of copper(I) cyanide. Environ Sci Technol. 2005;39(10):3849-54.
Sharma, V. K., Burnett, C. R., Yngard, R. A., & Cabelli, D. E. (2005). Iron(VI) and iron(V) oxidation of copper(I) cyanide. Environmental Science & Technology, 39(10), 3849-54.
Sharma VK, et al. Iron(VI) and iron(V) Oxidation of copper(I) Cyanide. Environ Sci Technol. 2005 May 15;39(10):3849-54. PubMed PMID: 15952395.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Iron(VI) and iron(V) oxidation of copper(I) cyanide. AU - Sharma,Virender K, AU - Burnett,Christopher R, AU - Yngard,Ria A, AU - Cabelli,Diane E, PY - 2005/6/15/pubmed PY - 2005/9/13/medline PY - 2005/6/15/entrez SP - 3849 EP - 54 JF - Environmental science & technology JO - Environ Sci Technol VL - 39 IS - 10 N2 - Copper(Il) cyanide (Cu(CN)4(3-)) in the gold mine industry presentsthe biggest concern in cyanide management because it is much more stable than free cyanide. Cu(CN)4(3-) is highlytoxic to aquatic life; therefore, environmentally friendly techniques are required for the removal of Cu(CN)4(3-) from gold mine effluent. The oxidation of Cu(CN)4(3-) by iron-(VI) (FeVIO4(2-), Fe(VI)) and iron(V) (FeVO4(3-), Fe(V)) was studied using stopped-flow and premix pulse radiolysis techniques. The stoichiometry with Fe(VI) was determined to be 5HFeO(4-) + Cu(CN)4(3-) + 8H2O - > 5Fe(OH)3 + Cu2+ + 4CNO- +3/202 + 6OH-. The rate law for the oxidation of Cu(CN)4(3-) by Fe(VI) was found to be first-order with each reactant. The rates decreased with increasing pH and were mostly related to a decrease in concentration of reactive protonated Fe(VI) species, HFeO4-. A mechanism is proposed that agrees with the observed reaction stoichiometry and rate law. The rate constant for the oxidation of Cu(CN)4(3-) by Fe(V) was determined at pH 12.0 as 1.35 +/- 0.02 x 10(7) M(-1) s(-1), which is approximately 3 orders of magnitude larger than Fe(VI). Results indicate that Fe(VI) is highly efficient for removal of cyanides in gold mill effluent. SN - 0013-936X UR - https://www.unboundmedicine.com/medline/citation/15952395/Iron_VI__and_iron_V__oxidation_of_copper_I__cyanide_ L2 - https://doi.org/10.1021/es048196g DB - PRIME DP - Unbound Medicine ER -