用铬(VI)—二苯胺磺酸钠氧化还原显色反应测定废水中的微量铬(VI)

DETERMINATION OF TRACE Cr(VI) IN WASTE WATER WITH OXIDATIONREDUCTION REACTION OF Cr(VI)SODIUM DIPHENYLAMINE SULFONATE

研究了在硫酸介质中，二苯胺磺酸钠被铬（ＶＩ）氧化反应的最佳条件。反应产物的最大吸收波长为５６０ｎｍ，表观摩尔吸光系数为２．５×１０４Ｌ·ｍｏｌ－１·ｃｍ－１，在一定量的二苯胺磺酸钠溶液中，铬（ＶＩ）含量在０～３０μｇ·（２５ｍＬ）－１范围内符合比耳定律，该方法用于废水中微量铬（ＶＩ）的测定，结果满意。

The optimum condition under which sodium diphenylamine sulfonate was oxided by Cr(VI) in H2SO4 medium was studied. The maximum absorption wavelength of the oxdied product was 560nm with molar absorptivity 2.5×104L·mol-1·cm-1. In a certain concentration of sodium diphenylamine sulfonate,Beers Law was obeyed in the range of 0～30μg/25mL for Cr(VI). This method has been used to determinate Cr(VI) in waste water with a satisfactory result.