Electrochemical detection of thiosulfate in the presence of sulfate ion using stainless steel electrode modified by gold

摘要

A highly sensitive electrochemical electrode was fabricated by plating gold on surface of a stainless steel electrode for detection and measurement of thiosulfate ion in process water. Cyclic voltammetry and differential pulse amperometry were used for characterization of electrochemical response towards thiosulfate ion. The electrode showed linear response and excellent sensitivity with the detection limits from 50 ppm to 900 ppm for S_2O_3~(2-). The optimization of medium pH for S_2O_3~(2-) ion was studied and found to be suitable for flotation water measurement. Effects of SO_4~(2-) as an interference ion were investigated and found that it did not interfere with S_2O_3~(2-) detection where the signal changes were below 5%. The Au modified stainless steel (316L) electrode showed high reproducibility and stability.