直接电位法测定工业废水中的硫氰酸根离子

Determination of thiocyanate anion in waste water of industories by direct potential method using thiocyanate anion selective electrode

用直接电位法测定了统扑净生产废水和印染厂排放废水中硫氰酸根的浓度。在温度为 1 6℃ ,浓度为 0 .0 2 mol/L HCl的体系中 ,以功能高分子 PVC-双硫腙 -铜 ( I)载体的 SCN-离子电极在 SCN-离子浓度为 1 .0× 1 0 -2 ～ 5× 1 0 -6mol/L时呈能斯特响应 ,斜率为 58± 2 m V/dec,检出限为 2 .0× 1 0 -6mol/L。电极的选择性次序为 :SCN->>Cl O4 -～Sal->>Cl->NO3 ->HPO4 2 ->SO4

PVC diphenylthiocabazone Cu(Ⅰ) liquid membrane anion selective electrodes were used to determine SCN -.The Nerstian response of the electrodes was from 10 -2 to 5.0×10 -6 mol/L for thiocyanate with the slope of 58±2 mV/dec (16℃) in 0 02 mol/L hydrochloride acid solution. The detection limit was 2×10 -6 mol/L . The selectivity sequence observed is:SCN ->>ClO 4 -～Sal ->> Cl - >NO 3 - >HPO 4 2- >SO 4 2- .The method was applied to determination of SCN - in waste water with satisfactory results.