2-(5-溴-2-吡啶偶氮)-5-二甲氨基苯胺激光热透镜光谱法测定微量钯  

Determination of palladium by laser thermal lens spectrometry using 2-( 5-bromo-2-pyridylazo )-5-dimethylaminoaniline

作　　者：韩权[1,2] 郝甜甜[2] 霍燕燕[1] 杨晓慧[1] 罗敏[1] 翟云会[1] 

机构地区：[1]西安文理学院化学与化学工程学院,西安710065 [2]延安大学化学与化工学院,延安716000

出　　处：《分析试验室》2014年第5期574-577,共4页Chinese Journal of Analysis Laboratory

基　　金：陕西省自然科学基础研究计划项目(2010JM2018);西安市科技计划项目(CXY1352WL04)资助

摘　　要：基于2-（5-溴-2-吡啶偶氮）-5-二甲氨基苯胺（5-Br-PADMA）与钯（Ⅱ）的高选择}生显色反应，建立了激光热透镜光谱法测定微量钯的新方法。在0．6mol／LHCl04介质中，于室温下放置10min，Pd（Ⅱ）与5-Br．PADMA反应形成稳定的青蓝色配合物，其最大吸收波长位于611nlTl处，与所用He—Ne激光器输出波长632．8nnl能较好匹配。钯质量浓度在5—150ng／mL范围内与激光热透镜信号强度呈线性关系，检出限为1．6ng／mL，以工作曲线的斜率计算，灵敏度较光度法提高115倍。常见金属离子及10倍量的铂、铑、铱、钌、锇和金等贵金属离子不干扰钯的测定，方法具有良好的选择}生。本法应用于催化剂、矿石和合金中钯的测定。A new method for the determination of trace palladium based on the highly selective color reaction between 2 - （ 5-bromo - 2-pyridylazo ） - 5-dimethylaminoaniline （ 5-Br-PADMA ） and palladium （ II ） by laser thermal lens spectrometry has been established. The experimental results show that Pd （II） reacts with 5-Br- PADMA in strong acidic media at room temperature for 10 min to form a stable complex showing maximum absorption wavelength at 611 nm which is matched well with the wavelength of the He-Ne laser （632.8 nm）. The linear range of this method is 5 ~ 150 ng/mL for palladium and the detection limit is 1.6 ng/mL. The sensitivity was enhanced by 115 times compared to conventional spectrophotometric method. The method has excellent selectivity. The common metal ions do not interfere, so do the precious metal ions, such as Pt （IV）, Rh（III） ,Ir（III）, Ru （III）, Os （IV） and Au （III）, in 10 times of Pd. This method has been applied to the ditermination of Pd in molecular sieve, alloy and ore.

关 键 词：激光热透镜光谱法 2-(5-溴-2-吡啶偶氮)-5-二甲氨基苯胺 钯 

分 类 号：O657.3[理学—分析化学]