Removal of Cyanide by Ferrate(VI): Effect of Metals and Ethylenediaminetetraacetate
Metal-cyanide complexes are found in metal finishing rinse water. The effect of Zn (II), Ni (II), and ethylenediaminetetraacetate on cyanide removal by ferrate (VI) (FeVIO4 2-, Fe (VI)) was thus investigated by studying the kinetics and stoichiometry of the reactions of Fe (VI) with cyanide present in mixtures of Zn(Ⅱ)-cyanide, Ni(II)-cyanide, and Ni (II)-cyanide-EDTA at pH 9.0. The concentrations of cyanide, Zn (II), Ni (II), and EDTA in the experiments were 500 μm, 200 μm, 170 μm and 500 μm, respectively. The oxidation of cyanide by Fe (VI) decreased in the presence of Zn (II) and Ni (II) ions. The decrease by Zn (II) ions was minimal, but Ni (II) ions caused a very significant decrease in the oxidation rate. Zn (II) ions had almost no effect on the cyanide removal efficiency by Fe (VI) and the stoichiometry of Fe (VI): cyanide was approximately 1:1, similar to the stoichiometry in the absence of Zn (II) ions. The presence of Ni (II) ions increased the demand for Fe (VI) with a stoichiometry of 2:1 (Fe (VI): cyanide). However, addition of EDTA into a Ni (II)-cyanide mixed solution eliminated such excess demand for Fe (VI). The destruction of cyanide by Fe (VI) resulted in cyanate ion as the product of the reaction. The experiment on removal of cyanide from the rinse water using Fe (VI) was conducted. The results were compared with the previous results and are briefly discussed.
Cyanide Ferrate EDTA Ozidation Removal Cyanate Detozification
Khemarath OSATHAPHAN Patarawan TIYANONT Ria A.YNGARD Virender K.SHARMA
National Center of Excellence for Environmental and Hazardous Waste Management,Chulalongkorn Univers Interdisciplinary Program in Environmental Science,Chulalongkorn University,Thailand Chemistry Department,Florida Institute of Technology,150 West University Boulevard,Melbourne,FL 3290
国际会议
2009 International Symposium on Environmental Science and Technology(2009环境科学与技术国际会议)
上海
英文
966-969
2009-06-02（万方平台首次上网日期，不代表论文的发表时间）