Analysis Voltammetry of Cyanide and Process Electrolytic Removal of Cyanide in Effluents

Abstract

This work uses the methodology of cathodic stripping voltammetry with a mercury drop electrode to separately and simultaneously quantify cyanide (CN-) of other species present in industrial effluents such as toxic metals (Cd2+, Zn2+), sulfides (S2-) and thiocyanate (SCN-). Voltammetry is a technique for electroanalytical study of the relationship between current and potential during the electrolysis of a chemical species, thus providing measures of direct quantification of analytes, which justifies the use of the technique to monitor these species. This technique has been used to determine the residual cyanide in effluents after treatment in the electrolytic cell laboratory developed with in situ generation of chlorine (Cl2), under alkaline conditions, aiming at the destruction of cyanide in carbon dioxide (CO2) and nitrogen (N2), non-toxic products. The results presented in laboratory assays have been quite satisfactory. Therefore, this technique can be used to quantify the amount of cyanide in industrial effluents.