2-(5-碘-2-吡啶偶氮)-5-二甲氨基苯胺与钌(Ⅱ)的显色反应及其应用  

Color reaction of 2-(5-iodine-2-pyridylazo)-5-dimethylaminoaniline with ruthenium(Ⅱ) and its application

作　　者：韩权[1,2] 霍燕燕[2] 陈虹[1] 杨晓慧[1] 

机构地区：[1]西安文理学院化学系,陕西西安710065 [2]延安大学化学与化工学院,陕西延安716000

出　　处：《冶金分析》2010年第5期54-57,共4页Metallurgical Analysis

基　　金：西安市科技计划项目(CXY09015-5)

摘　　要：研究了2-(5-碘-2-吡啶偶氮)-5-二甲氨基苯胺(5-I-PADMA)与Ru(Ⅱ)的显色反应并以5-I-PADMA作为显色剂分光光度法测定钌的方法。在pH4.0～6.2 HAc-NaAc缓冲溶液中,盐酸羟胺存在并加热条件下,Ru(Ⅱ)可与5-I-PADMA形成稳定的1∶2络合物。该络合物形成后,可稳定存在于无机酸(HCl,H2SO4,HClO4,H3PO4)中,适宜的酸浓度范围分别为0～2.0 mol/L HCl,0～1.8 mol/L H2SO4,0～1.7 mol/L HCl O4和0～3.0 mol/LH3PO4,其最大吸收峰位于618 nm,表观摩尔吸光系数达5.22×104L.mol-1.cm-1。钌(Ⅱ)浓度在0～1.0 mg/L范围内符合比尔定律。利用EDTA作掩蔽剂,可允许较大量的常见金属离子存在。所拟方法用于钌炭催化剂和钌分子筛中微量钌的测定,相对标准偏差分别为1.2%和0.41%(n=6)。The coloring reaction of 2-（5-iodine-2-pyridylazo）-5-dimethylaminoaniline（5-I-PADMA） with ruthenium（Ⅱ） was studied,and a new spectrophotometric determination method of ruthenium（Ⅱ） was established using 5-I-PADMA as coloring reagent.In HAc-NaAc buffer solution at pH 4.0-6.2,ruthenium（Ⅱ） could react with 5-I-PADMA to form a 1∶2 complex under heating in the presence of NH2OH·HCl.The complex was stable in inorganic acid.The appropriate concentration for HCl,H2SO4,HClO4 and H3PO4 was 0-2.0 mol/L,0-1.8 mol/L,0-1.7 mol/L and 0-3.0 mol/L,respectively.The maximum Absorption wavelength was at 618 nm,and the apparent molar Absorptivity was 5.22 ×10^4 L·mol^-1·cm^-1.Beer＇s law was obeyed for ruthenium（Ⅱ） in the range of 0-1.0 mg/L.Most of the common ions could exist using EDTA as masking reagent.The proposed method has been successfully applied to the determination of trace ruthenium in ruthenium-carbon catalyst and ruthenium-molecular sieve,with relative standard deviations（RSD） of 1.2 % and 0.41 %（n=6）,respectively.

关 键 词：钌 分光光度法 2-(5-碘-2-吡啶偶氮)-5-二甲氨基苯胺 

分 类 号：O657.32[理学—分析化学]