摘要
利用氟离子对H_2O_2—Fe(Ⅲ)—二苯胺磺酸钠催化反应体系的抑制作用,提出了一种测定痕量氟的动力学方法.在F^-含量为0～0.95μg·mL^(-1)范围内,1g(Am/Ai)(Am,Ai分别为非抑制反应和抑制反应体系的吸光度)与F^-离子浓度呈线性变化关系;表观摩尔吸光系数ε_(390)=4.25×10~5,方法灵敏度为0.019μg·mL^(-1).用本法测定了废水和自来水中的氟含量,结果良好.
A method for the determination of trace fluorine has been proposed based on the inhibitory effect of F- upon the catalytic redox reaction of Fe(Ⅲ) -H2O2-sodium diphenylamine sulfonate systems. Linear relationship between lg(Am/Ai) and F- concentration within the range of 0～0. 95μg· mL-1 was obtained. The apparent molar absorptivity is 4. 25×10 5 at λ= 390nm and the sensitivity of the method is 0.019μg · mL-1 . The method has been used for the determination of trace fluorine in water , and the results are satisfactory.
关键词
氟
动力学光度法
水
测定
Fluorine Trace analysis Kinetic-spectrophotometry
