铁(Ⅲ)-硫氰酸钾-结晶紫光度法测定高纯稀土中痕量铁  

Spectrophotometric Determination of Trace Iron in Highly Purity Rare Earth with Fe(Ⅲ)-SCN^--Crystal Violet System

作　　者：默丽萍[1] 

机构地区：[1]河北师范大学化学学院,石家庄市050091

出　　处：《光谱实验室》2002年第2期270-272,共3页Chinese Journal of Spectroscopy Laboratory

摘　　要：在 0 .0 3— 0 .0 6 mol/L的硫酸溶液中 ,在阿拉伯树胶存在下 ,铁与硫氰酸钾、结晶紫生成可溶性离子缔合物 ,该缔合物表观摩尔吸光系数为 4 .78× 10 5L· mol-1· cm-1,经甲基异丁基酮 (MIBK)萃取分离 ,铁的浓度在 0— 2 .5μg/m L范围内符合比耳定律。此方法用于高纯稀土中痕量铁的测定 。A method of extract for the spectrophotometric determination of trace iron has been developed.In a solution containing 0.03-0.06mol/L H 2SO 4,iron with potassium thioyanate and crystal violet forms soluble mixed ionic associated complex in the presence of Arabic gum.Its apparent molar absorptivity is 4.78×10 5L·mol -1 ·cm -1 at 540 nm.Beer′s law is obeyed for iron (Ⅲ) in the concentration range of 0-2.5μg/25mL. This method has been applied to the determination of trace amounts of iron in high purity rare earth via methylisobutylketone (MIBK)extractin with satisfactory results.

关 键 词：铁 稀土 硫氰酸钾 结晶紫 分光光度法 测定 高纯稀土 氧化铬 痕量分析 

分 类 号：O614.33[理学—无机化学] O614.81[理学—化学]