摘要
在硫酸-磷酸介质中,未经分离除去高浓度的Fe(Ⅲ),以二苯碳酰二肼作显色剂,与Cr(Ⅵ)形成有色配合物,在波长540nm处有最大吸收峰,显色程度与Cr(Ⅵ)含量成正比,Cr(Ⅵ)含量在0—50μg·(50mE)。范围内呈良好的线性关系,摩尔吸光系数为4.0×10^5L·mol^-1·cm^-1。将方法应用于工业品硝酸铁中微量铬的测定,相对标准偏差为4.06%(n=6),加标回收率在91.5%~105.2%之间。
In sulfuric acid and phosphoric acid medium, after removal of high concentration of Fe ( Ⅲ ) without separation, diphenylcarbazide formed a colored complex with Cr( Ⅵ ) and it had a maximum absorption peak at wavelength of 540nm. The color degree was directly proportional to content of Cr ( Ⅵ ) and the content of Cr (Ⅵ ) showed a good linear relationship between 0-50 μg/50mL. Molar absorption coefficient was 4.0 × 10^5L · mol^-1 × cm^-1. The method was applied to determine trace chromium in industrial ferric nitrate and the relative standard deviation was 4.06% (n=6), the recovery rate was 91.5%-105.2%.
出处
《化工技术与开发》
CAS
2013年第2期35-37,共3页
Technology & Development of Chemical Industry
关键词
分光光度法
二苯碳酰二肼
硝酸铁
铬
spectrophotometry
diphenylcarbazide
ferric nitrate
chromium