초록
수은방울전극에서 바로 시안이온을 시차펄스음극벗김 전압전류 법으로 측정한 결과 검출한계를 낮출수가 있었다. 가장 알맞는 실험조건은 다음과 같다. : 0.1M KCl-0.01M 인산염 지지전해질, pH 7, 석출전위 0.00V, 그리고 석출시간 3분이었다. 이 조건에서 검출한계는 $3{\times}10^{-7}M$ (8ppb) $CN^-$이다.
Direct differential-pulse cathodic stripping voltammetry on mercury electrode (HMDE) provides a sensitive technique for low level cyanide measurement in distilled and sulfide free solution. Cyclic voltammetry revealed the forming and redissolution reactions were reversible at pH 7 in 0.1M KCl-0.01M phosphate supporting electrolyte. The analytical conditions have been optimized. With deposition time of 3 min at deposition potential 0.00V(vs. Ag/AgCl) in this medium of pH7, quite reproducible and linear calibration curve was obtained down to $3{\times}10^{-7}M$ (8ppb) $CN^-$ which was the detection limit.