铬(Ⅵ)-邻硝基苯基荧光酮-表面活性剂显色反应的研究

Color Reaction of Chromium With 2,6,7-Trihydroxy-9-(o-nitrophenyI)fluorone in the Presence of Surfactant

本文研究了表面活性剂(以CTMAB为例)对Cr(Ⅵ)-硝基苯基荧光酮(NO_2-PF)显色反应的影响,发现CTMAB对此类显然体系有较强的增敏作用。着重探讨了Cr(Ⅵ)-οNO_2-PF-CTMAB显色反应的机理,认为在pH4.7～6.6实验条件下,Cr(Ⅵ)与ο-NO_2-PF之间是络合反应。

The effect of CTMAB on Cr( Ⅵ )-2,6,7-trihydroxy-9-(o-nitrophenyl) fluorone (o-NO2-PF) color reaction was investigated. The molar ratio of Cr( Ⅵ ) : o-NO--PF : CTMAB was found to be 1 : 2 : 2. The apparent molar absorptivity was 1. 1× 105 L · mol-1 · cm-1 at 582nm. Beer's law was obeyed in the range of 0 - 5. Oμg/25ml for Cr( Ⅵ ). It was indicated that the reaction of CrO5- with o-NO2-PF at pH 4. 7-6. 8 was a chelation.