催化光度法测定电厂废水中的微量氟化物

Catalytic spectrophotometric determination of trace fluoride in wastewater in power plants

研究了在 pH 2 .76氨基乙酸 -盐酸缓冲溶液中 ,Fe3 + 对H2 O2 氧化 2 ,4 -二氨基苯酚 (DAP)褪色具有催化作用 ,游离F-离子与Fe3 + 形成的稳定络合物 [FeF6]3 -可阻抑催化作用 ,阻抑程度与F-量线性相关。基于此 ,建立了测定微量F-的催化光度分析的新方法。结果表明 ,有色溶液的最大吸收波长为 5 0 0nm ,测定的线性范围为0 .0～ 9.0mg/L ,检出限为 0 .0 9mg/L ,RSD(n =6 ) <5 %。灵敏度高、选择性好、分析速度快 ,应用于电厂废水和自来水中微量F-的测定 。

When the pH value of glycine-HCl buffer solution is 2.76 ,Fe 3+ catalyzes strongly the fading reaction of 2,4-diamonophenol(DAP) by oxidizing with H 2O 2.Free F - ions and Fe 3+ form stable complexes 3- ,thus reducing its catalytic effect and its reducing extent is liner with the concentration of F -.Based on this study,a rapid and simple catalytic spectrophotometric method for the determination of F - ions has been developed.The results show that the range of determination is 0.0～9.0 mg/L for F -,the detection limit is 0.09 mg/L for F -,and RSD( n =6)<5%.The method has been applied to the determination of trace fluoride in power plants wastewater and running waters with satisfactory results.