Abstract： In HAc medium and with non-ionic surfactant of Tween-80 as sensitizer,ytterbium(Ⅲ) can inhibit the discoloration of evans blue(EB) by KBrO3. Therefore,a new inhibitory kinetic spectrophotometric method for the determination of trace ytterbium(Ⅲ) was studied. The effects of these factors such as absorption spectra, acidity, concentrations of reagent, influence of coexisting ions on the reaction were discussed and the kinetic parameters were tested. Under the optimum conditions, the linear range was 4-120 μg/L. The detection limit was 3.36×10-7g/L. The inhibitory reaction was the first order reaction and the apparent activation energy of the inhibitory reaction was 101.04 kJ/mol,and the reaction rate constant was 2.30×10-3/s.The sensitivity was increased by 2 times with the existence of surfactant Tween-80. The method was successfully applied to the determination of ytterbium(Ⅲ) in neodymium oxide,with the relative standard deviation of less than 2.7% and the recovery of 99%-101％.
王晓菊,高烨. 非离子表面活性剂增敏阻抑动力学光度法测定氧化钕中痕量镱（Ⅲ）[J]. 冶金分析, 2013, 33(4): 68-71.
WANG Xiao-ju,GAO Ye. Inhibitory kinetic spectrophotometric determination of trace ytterbium(Ⅲ) in neodymium oxide with sensitization of non-ionic surfactant. , 2013, 33(4): 68-71.
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