Determination of molybdenum in molybdenum tailing by methylene blue-potassium periodate catalytic kinetic spectrophotometry
WANG Xiang-ting1, FAN Xue-mei1,2, WANG Shu-min1
1.College of Chemical Engineering and Modern Materials of Shangluo University, Shangluo 726000, China; 2.Materials Science and Engineering of Shangluo, Shangluo 726000, China
Abstract：It was found through experiments that potassium periodate could oxidize methylene blue for fading in presence of sulfuric acid. Based on molybdenum had catalytic effect on this fading reaction, a new determination method of molybdenum was established in molybdenum tailing by catalytic kinetic spectrophotometry. The results showed that when the concentration of methylene blue, sulfuric acid and potassium periodate in coloring system was 0.012 g/L, 0.001 mol/L and 0.000 4 mol/L, respectively, the concentration of molybdenum in range of 0.02-0.6 mg/L exhibited good linearity to the absorbance change after the coloring system was heated at 60 ℃ for 13 min. The detection limit of method was 0.05 mg/L. Under the optimized experimental conditions, the apparent activation energy of catalytic system was Ea=47.31 kJ/mol, and the reaction rate constant was k=3.5×10-4/s. The proposed method was applied to the determination of molybdenum in molybdenum tailings from three different areas. The results were consistent with those obtained by atomic absorption spectrometry(AAS). The relative standard deviation (RSD, n=11) was 2.1%-2.9%, and the recoveries were between 97% and 102%.
王香婷,樊雪梅,王书民. 亚甲基蓝-高碘酸钾催化动力学光度法测定钼尾矿中钼[J]. 冶金分析, 2015, 35(6): 57-60.
WANG Xiang-ting, FAN Xue-mei, WANG Shu-min. Determination of molybdenum in molybdenum tailing by methylene blue-potassium periodate catalytic kinetic spectrophotometry. , 2015, 35(6): 57-60.
