结晶紫催化氧化光度法测定水中亚硝酸根

Catalytic Oxidated Photometric Determination of Nitrite in Water with Crystal Violet

研究了稀磷酸介质亚硝酸根催化溴酸钾氧化结晶紫的反应 ,并根据亚硝酸根的催化作用特性 ,建立了一种测定亚硝酸根的新催化光度法 .该法测定亚硝酸根(NO2 )的线性范围为 0 .0 2 5～ 6 .0 μg/2 5ml,方法灵敏度为 8.91× 1 0 1 0 g/ml.方法选择性好 ,室温下操作尤为方便 ,已应用于测定几种水样中亚硝酸根的含量 ,其RSD <4.8% ,样品加标平均回收率为 96 .5 % .

A new catalytic photometric methood for determination o f nitrite was developed,based on the ability of nitrite to catalyze the redox re action of crystal violet with potassium bromate in a dilute phosphoric acid medi um.The linear range of the method for determination of nitrite is 0.025～6.0μg/ 25ml,and sensitivity of 8.91×10^-10g/ml.It has been used to determine nitr ite in water samples with high selectivity.It can be operated conveniently at an ambient temperature.The relative standard deviation (RSD) of method is less tha n 4.8%, and average recovery of 96.5%.