4-(2-吡啶偶氮)-邻苯三酚与Mo(Ⅵ)的显色反应研究  

STUDY ON THE COLOR REACTION OF MOLYBDENUM (Ⅵ) WITH THE NEW REAGENT PAPG IN THE PRESENCE OF CTMAB

作　　者：史传国[1] 姚成[2] 

机构地区：[1]南通师范学院化学系,南通226007 [2]南京工业大学理学院

出　　处：《理化检验（化学分册）》2004年第10期584-585,591,共3页Physical Testing and Chemical Analysis(Part B:Chemical Analysis)

基　　金：江苏省教育厅资助项目(02KJD150008)

摘　　要：研究了新显色剂4-(2-吡啶偶氮)-邻苯三酚(PAPG)在溴化十六烷基三甲基铵(CTMAB)存在下与Mo(Ⅵ)的显色反应。在pH 4.0-6.0范围内,PAPG与Mo(Ⅵ)反应生成稳定的橙红色配合物。该配合物中Mo(Ⅵ)与PAPG的组成比为1:2;其最大吸收波长为507nm,对比度为76nm;在20℃、μ＝0.1和pH 4.8时,其表观稳定常数为2.40×106,表观摩尔吸光系数为3.92×104L·mol-1·cm-1。钼含量在0-0.80mg·L-1范围内服从比耳定律。该方法具有高灵敏度与高选择性,用于合金钢中钼的测定,结果满意。In an acetate buffer of pH 4. 0-6. 0, and in the presence of CTMAB, the newly synthesized reagent 4-(2-pyridylazo)-pyrogallol (PAPG) reacts with Mo(NI) to form a stable orange-red complex having its absorption maxima at 507nm while the absorption maxima of the reagent itself lies at 431nm (△λ = 76nm). The apparent molar absorptivity of this complex is found to be 3. 92×104L · mol-1 λ cm-1, and its stability constant to be 2. 4 ×106. The mole ratio of the reagent to Mo( VI) is determined and a value of (Mo( VI) ! R) 1 : 2 is obtained. Beer's law is obeyed in the range of 0 to 0. 80mg of Mo(VI) per liter of solution. This method has been applied to the determination of molybdenum in samples of alloy steel after a separation by NaOH-precipitation,

关 键 词：吸光光度法 钼 4-(2-吡啶偶氮)-邻苯三酚 溴化十六烷基三甲基铵 合金钢 

分 类 号：O657.3[理学—分析化学]