催化退色光度法测定痕量铱的研究  

Catalytic discoloring spectrophotometry for the determination of trace amount of iridium(Ⅳ)

作　　者：杨明惠[1] 赵霞[1] 郭洁[1] 曹秋娥[2] 

机构地区：[1]大理学院生命科学与化学学院,云南大理671000 [2]云南大学化学科学与工程学院,云南昆明650091

出　　处：《化学试剂》2007年第8期474-476,共3页Chemical Reagents

基　　金：大理学院科研基金资助项目(2002X04)

摘　　要：在硫酸介质中铱(Ⅳ)对高碘酸钾氧化变色酸2R的反应具有催化作用,建立了测定痕量铱的新催化光度法。测定铱的线性范围为0.008～0.080μg/mL,检出限为2.53×10-6g/L。该催化反应对铱(Ⅳ)和变色酸2R均为一级反应,其表观活化能为56.6kJ/mol。用该方法测定了岩矿和冶金产品中铱的含量,相对标准偏差(n=6)为0.57%～1.55%,加标回收率为98.5%～102.3%。A new kinetic spectrophotometric method has been developed for the determination of iridium（ Ⅳ ） based on its catalytic effect on the oxidation reactions of ehromotrope 2R by KIO4 in a H2SO4 medium.The linear range of the method for the determination of Ir（Ⅳ ） is 0.008- 0.080 μg/mL with a detection limit of 2.53 × 10^-6 g/L.The catalytic reaction is a first-order one for both Ir（Ⅳ ） and chromotrope 2R with an apparent activation energy of 56.6 kJ/mol. The method features good selectivity and has been successfully applied for the determination of iridium in the metallurgical products and ore samples with the relative standard deviation ranging from 0.57% to 1.55% and the recovery rate ranging from 98.5% to 102.3%.

关 键 词：铱 催化光度法 高碘酸钾 变色酸2R 

分 类 号：O657.32[理学—分析化学]