SYNTHESIS OF A NEW CHROMOGENIC REAGENT 4-CHLORO-2- SULFOBENZENEDIAZOAMINOAZOBENZENE AND STUDY ON ITS COLOR REACTION WITH CADMIUM(II)

The color reaction of cadmium(Ⅱ) with a new reagent 4 chloro 2 sulfobenzenediazoaminoazo benzene abbreviated as CSDAA was studied and is reported in this paper. In the presence of Triton X 100 the reagent reacts with cadmium(Ⅱ) to form a red complex with a molar ratio of 3∶1 in an ammonical buffer solution of pH 10.6. The maximum absorption of the complex is at 530nm and the apparent molar absorptivity is found to be 2.0×10 5. Beer′s law is obeyed in the rang of 0~20μg of cadmium in 25ml of solution. This mothod has been used to determine trace amounts of cadmium(Ⅱ) in waste water with satisfactory results.