双波长双指示物催化动力学光度法测定痕量银的研究  

Study on the dual-wavelength and dual-indicator catalytic kinetic spectrophotometry for determination of trace silver

作　　者：朱庆仁[1] 孙登明[1] 马伟[1] 靳春芝 

机构地区：[1]淮北煤炭师范学院化学系,安徽淮北235000

出　　处：《冶金分析》2007年第5期48-50,共3页Metallurgical Analysis

基　　金：安徽教育厅自然科学基金项目(2004KJ320;200KJ140);淮北市科技计划基金项目(040145)

摘　　要：研究了在pH 3.5的HAc—NaAc缓冲溶液介质中,以乳化剂OP为增溶剂,邻菲罗啉和α,α’,-联吡啶活化银离子催化过硫酸钾氧化亚甲基蓝和甲基紫褪色的指示反应,通过测量660 nm和590 nm下催化体系和非催化体系吸光度的变化,建立了双波长双指示物催化动力学光度法测定痕量银的新方法。在最佳实验条件下,测定银的线性范围为0.002～0.080μg/mL,检出限为6.5×10^(-10)g/mL。用于定影废液中痕量银的测定,相对标准偏差为1.5%,加标回收率为98.3%。A new dual-wavelength and dual-indicator catalytic kinetic spectrophotometric method for the determination of trace silver is studied. The method is based on the catalyzing effect of silver on discoloring reaction of methylene blue and methyl violet by oxidation of potassium persulfate in the presence of 2,2＇-dipyridyl and phenothrolile as activators and emulsifier OP as a solubilization agent in the buffer media of HAc-NaAc at pH3.5. The absorbances in catalytic and uncatalytic systems are measured at 660nm and 590nm. Under the optimum conditions,the linear range of determination of Ag （Ⅰ）is 0. 002-0. 080 μg/mL. The detection limit is 6.5 × 10^-10 g/mL. The method has been used to the determination of trace silver in fixing waste with relative standard deviation of 1.5% and recovery of 98. 3%.

关 键 词：银 催化光度法 双波长 双指示物 次甲基蓝 甲基紫 

分 类 号：O657.3[理学—分析化学]