【摘要】 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 + 形成的稳定络合物可阻抑催化作用 ,阻抑程度与F-量线性相关。基于此 ,将流动注射技术引入分析体系 ,建立了测定微量F-的流动注射催化光度分析法。结果表明 :λmax为 5 0 0nm ,F-测定的线性范围为 0 .0～ 9.0mg/L ;检出限为 0 .0 9mg/L ;测定频率为 90次 /h ;RSD <5 % (n =6 )。本法灵敏度高 ,选择性好 ,分析速度快 ,可用于测定矿井水和自来水中微量F-。更多还原

【Abstract】 In pH 2.76 glycine HCl buffer solution, trace Fe 3+ catalyzes strongly the fading reaction of 2,4 diaminophenol (DAP) by oxidizing with H 2O 2,free F - ions form stable complexes with Fe 3+ ,thus reducing the catalytic effect of Fe 3+ and its reducing extent is linear with the concentration of F -. Based on this study,a rapid and simple flow injection spectrophotometric method has been developed for the determination of F - ions. The experimental results show that the linear range for the determination is 0.0～9.0 mg/L F -,and detection limit is 0.09 mg/L F -.The determination frequency is about 90 times/h.RSD<5%( n =6).The method has been applied to the determination of trace fluoride in mining and tap waters with satisfactory results.更多还原