反相流动注射催化光度法测定NO_2^-的研究

Determination of Trace Nitrite with RP-Flow Injection-Catalytic Spectrophotometry

基于亚硝酸根在酸性条件下对溴酸钾氧化胭脂红酸的褪色反应的催化作用 ,将反相流动注射技术与催化光度法相结合测定亚硝酸根的含量。对实验条件进行了优化。室温下 ,当 [KBr O3 ]=0 .14 mol/L,[胭脂红酸 ]=3.2× 10 -4mol/L,[H2 SO4]=1.4 mol/L时 ,方法的线性范围为 1— 10 ng/m L,检出限为0 .7ng/m L。用于几种河水水样测定 ,结果满意。

The amount of nitrite in river was determined by RP-flow injection-catalytic spectrophotometry based on the catalytic color fading reaction of potassium bromate with carminic acid by nitrite in acidic media.The Experiment conditions were optimized.With 0.14mol/L of KBrO 3,3.2×10 -4 mol/L of carninic acid and 1.4mol/L of H 2SO 4 at 25℃,the detection limit for nitrite is 0.7ng/mL in linear range of 1—10ng/mL.The method was applied to the determination of trace nitrite in river water with satisfactory results.