碱性高锰酸钾光度法测定水中的苯胺类物质

Determination of Trace Aniline by Alkalinity Potassium Permanganate

在碱性条件下,高锰酸钾氧化苯胺引起自身颜色的变化,并且体系吸光度的变化值和苯胺的含量成正比。据此建立了光度法测定微量苯胺的新方法,方法分别选择显色波长430,610 nm和褪色波长525 nm进行测定。3波长下表观摩尔吸光系数分别为1.60×10^4L/（mol.cm）,2.09×10^4 L/（mol.cm）和2.09×10^4 L/（mol.cm）。苯胺质量浓度均在2.5-30μg/10 mL范围内符合比尔定律。将该方法用于测定水样中的苯胺含量,3波长下均获得满意结果。

A new speetrophotometric method for the determination of aniline with potassium per- manganate was developed. In the medium of NaOH solution, the color of potassium permanga- nate changed obviously, and the degree of color change was proportional to the concentration of aniline. Aniline was determined at the coloring wavelength of 430, 610 nm with 1.60×10^4 L/ （mol·cm）, 2.09×10^4 L/（mol·cm） and the fading wavelength of 525 nm with apparent molar absorption of 1.42×10^4 L/（mol·cm）. Beer＇s law was obeyed in the aniline concentration range of 2.5-30μg/10 mL. It has been used in the determination of aniline in water at the three wave- lengths with satisfactory results obtained.