摘要
采用固相萃取分离技术结合分光光度法,提出了一种新的环境水样中铬(Ⅵ)的测定方法。在强酸性介质中,铬(Ⅵ)与二苯碳酰二肼反应生成Cr(Ⅲ)-二苯偶氮碳酰肼有色络合物,该有色络合物被Sep-Pak C18柱吸附,并可用丙酮和硫酸混合洗脱液洗脱,在540 nm波长下测定其吸光度。本方法灵敏度高,选择性好,检测限0.85μg/L(n=7,p=0.05),测定实际水样中铬(Ⅵ)的相对标准偏差为2.5%(n=3),回收率(盐含量为5 g/L)为104%。
A new method of preconcentration and determination Cr（Ⅵ） in environmental water sample is developed using solid phase extraction of Sep-Pak C18 cartridges followed by spectrophotometry. Diphenylcarbazide reacted with Cr（Ⅵ） in the mediun of strong acid to form the Cr（Ⅲ）-diphenylcarbazone color complex, which can be adsorbed on sep-Pak C18 column and can be eluted from the column with a mixture of acetone and sulfuric acid. The absorbnce of the eluant was measured at 540 nm. The detection limit of the method is 0. 85 μg/L for Cr（Ⅵ）. The method is used to the determination of Cr（Ⅵ） in actual water samples with the RSD of 2.5% （n= 3） and the recovery of 104% （containing 5 g/L salt）.
出处
《冶金分析》
CAS
CSCD
北大核心
2008年第2期48-51,共4页
Metallurgical Analysis
关键词
固相萃取
分光光度法
铬(Ⅵ)
solid phase extraction
spectrophotometry
chromium（Ⅵ）
