Citation: . Spectrophotometric Determination of Microamounts of Cadmium with 4, 4'-Dinitroazoaminobenzene. Chinese Journal of Analytical Chemistry, 1983, 11(11): 863-865. [复制]
Spectrophotometric Determination of Microamounts of Cadmium with 4, 4'-Dinitroazoaminobenzene
A sensitive spectrophotometric microdetermination of cadmium with dinitroazoaminobenzene (DNAAB) is described. The cadmium can be determined owing to decressing in the absorbance of 1.3μgmol of DNAAB in 50 ml of 0.25N-KOH solution at 510nm. The maximum and constant absorption of DNAAB vs Cd (Ⅱ)-DNAAB is attained in the range of 45-90 minutes after initiation of the formation of the complex of cadmium (Ⅱ) with DNAAB in a molar ratio of 1:3. Beer's law is obeyed in the range 0-22.5μg of Cd (Ⅱ)/50ml,and Sandell's sensitivity is 9.3×10-4μg/cm2. The effects of 57 ion species or compounds were examined. Hg (Ⅱ) and Ag (Ⅰ) seriously interferred with the determination,but 5μg of Hg (Ⅱ) or Ag (Ⅰ) can be masked by addition of 50mg of Cl-. Micro amounts of cadmium in ores and waste waters can be successfully determined with the method after suitable concentration and separation.