孔雀石绿-溴酸钾催化分光光度法测量亚硝酸根

采用流动注射技术和催化分光光度法相结合,研究了在磷酸介质中,亚硝酸根对溴酸钾氧化孔雀石绿褪色反应的催化作用及其动力学条件,建立了催化动力学光度法测定痕量亚硝酸根的新方法。方法检出限为0.9ng/mL,测定的线性范围为5—60ng/mL,且线性相关系数为0.9983,对于浓度为30ng/mL的亚硝酸根标准液测定的相对标准偏差仅为1.0。该方法适用范围广,具有较好的准确性、稳定性和灵敏度,且实验操作方便、快速。利用此方法测定不同水样中的亚硝酸根,加标回收率在88.6%—104.8%之间,分析结果令人满意。

Determination of Nitrite by Malachite Green-Potassium Bromate Catalytic Spectrophotometry

The catalysis and dynamics conditions of fading reaction for nitrite catalysis on oxidation of malachite green by potassium bromate were investigated by flow injection techniques combining with catalytic spectrophotometry in phosphoric acid medium,and the method for the determination of trace nitrite determined by spectrophotometry was established.The detection limit of method was 0.08ng/mL,and the linear range was 5—60ng/mL with the correlation coefficient of 0.9983,and RSD of nitrite standard solution was 1.0% for the nitrite concentration of 30ng/mL.The method has wide applied range,good accuracy,stability and sensitivity with simple and rapid operation.The method was applied to determining the nitrite in the different water sample,and the standard recoveries were in the range of 88.6%—104.8% with satisfactory results.