Abstract：The fading reaction of methylene blue when methylene blue was oxidized by potassium brominates can be easily inhibited by trace nickelⅡ in HCl medium under 65 ℃ heating conditions. The optimum experimental conditions were studied,and a new inhibitory kinetic spectrophotometry method of trace nickel Ⅱ determination was established. The absorbency difference ΔA between non-inhibitory reaction (absorbency A0) and inhibitory reaction (absorbency A) remained good linear relationship with the mass concentration (ρ) of nickel Ⅱ in the range of 0.10-1.50 μg/25mL at 602 nm. The detection limit was 2.44×10-10 g/mL, and kinetic parameters were determined which showed that the reaction was the first order reaction to nickelⅡ and pseudo first order reaction to the total reaction. The apparent ratio constant of the reaction was 3.750×10-4 /s and the apparent activation energy was 47.19 kJ/mol. The method was also applied to the determination of trace nickel Ⅱ in vanadium iron and low alloy steel with the recovery of 98%-102%,and the results were consistent with the certified value.
王洪福;苏智先*;张素兰;何黎明;刘丽. 甲基蓝褪色阻抑动力学光度法测定痕量镍[J]. 冶金分析, 2011, 31(4): 61-64.
WANG Hong-fu;SU Zhi-xian*;ZHANG Su-lan;HE Li-ming;LIU Li. Determination of trace nickel with inhibition of the fading of methylene blue kinetic spectrophotometry. , 2011, 31(4): 61-64.
