溴酸钾氧化二甲苯蓝FF催化光度法测定痕量亚硝酸根

Catalytic Spectrophotometric Determination of Trace Nitrite Based on the Oxidation of Xylene Cyanol FF by Potassium Bromate

本文研究了在稀磷酸介质中、亚硝酸根催化溴酸钾氧化二甲苯蓝FF褪色反应的条件、建立了催化光度测定痕量亚硝酸根的新方法．本法具有较高的灵敏度和良好的选择性，亚硝酸根含量在0．5～24ng／ml范围内与lg（A0/A）成线性，用于测定水样和土壤中的亚硝酸根，获得满意结果。

A new catalytic spectophotometric method for determining trace nitrite has been described.The method was based on the nitrite catalyzed oxidation of xylene cyanol FF by potassium bromate under the following conditions: 0.036mol/L H3PO4, 4 ×10 -5mol/L xylene cyanol FF, 5 × 10-3mol/L KBI-O3, temperature (90 ±1 )℃. heating 5min, and measuring the absorbance values at wavelength of 614nm. The linear range for determination was 0. 5 ～ 24ng/ml for nitrite. The method has been used to determine trace nitrite in water and soil samples with satisfactory results.