电感耦合等离子体原子发射光谱法测定某些特殊试样中痕量铬(Ⅵ)--共沉淀法快速分离铬(Ⅲ)  

ICP-AES Determination of Cr(Ⅵ) in Certain Special Samples——Preliminary Separation of Cr(Ⅲ) by co-Precipitation

作　　者：刘崇华[1] 陈阳[1] 黄理纳[1] 刘伟红[1] 蚁乐洲[1] 冼燕萍 

机构地区：[1]广东出入境检验检疫局技术中心,广州510623 [2]广州市产品质量监督检验所,广州510110

出　　处：《理化检验（化学分册）》2008年第4期350-351,354,共3页Physical Testing and Chemical Analysis(Part B:Chemical Analysis)

基　　金：广东出入境检验检疫课题项目(GDJ42-2002)资助

摘　　要：电感耦合等离子体原子发射光谱法(ICP-AES)应用于某些特殊试样(特别试液背景色泽很深或略带混浊者)中铬(Ⅵ)的测定。试样溶液中共存的铬(Ⅲ)及一些其他金属离子的干扰,借在pH 9.5的氨性溶液中以Fe(Ⅲ)离子作载体共沉淀分离予以消除,用ICP-AES法测定滤液中铬(Ⅵ)。试验表明:铬(Ⅲ)共存量达100 mg.L-1时,经沉淀分离后不影响铬(Ⅵ)的测定,铬(Ⅵ)的回收率接近100%。此方法的检出限(3σ)为0.054 mg.L-1,应用所提出的方法测定了一种黄色油漆中在铬(Ⅲ)共存下的铬(Ⅵ),平行7次测定,相对标准偏差为1.3%。ICP-AES was applied to the determination of Cr（Ⅵ ） in certain special samples, especially those with deep color or slight turbidity. Interferences of Cr（ Ⅲ ） and some other co-existing metal ions were eliminated by precipitation with aq. ammonia at pH 9. 5 using Fe（Ⅲ） ion as carrier, and Cr（Ⅵ）was determined in the filtrate by ICP-AES. It was proved that 100 mg · L^-1 of Cr（ Ⅲ ） were tolerable and the recovery of Cr（Ⅵ） obtained, after precipitation were very near to 100%. Detection limit （3σ） of the method was found to be 0. 054 mg · L^-1. The proposed method was used for the determination of Cr（ Ⅵ ） in presence of Cr（ Ⅲ） in a sample of yellow colored paint which was digested with conc. HNO3 preliminarity, the value of RSD＇s （n=7） obtained were 1.3%.

关 键 词：电感耦合等离子体原子发射光谱法 铬(Ⅵ) 共沉淀 

分 类 号：O657.31[理学—分析化学]