Highly Selective Adsorptive Cathodic Stripping Voltammetric Determination of Uranium in the Presence of Pyromellitic Acid
Highly Selective Adsorptive Cathodic Stripping Voltammetric Determination of Uranium in the Presence of Pyromellitic Acid
复制标题
DOI：
10.1002/elan.200403145
复制
发表时间：
2005-04
期刊：
影响因子：
3
通讯作者：
M. Gholivand;H. R. Nassab
中科院分区：
文献类型：
--
作者：
M. Gholivand;H. R. Nassab
本文提出了一种高灵敏度、高选择性的吸附阴极溶出法测定痕量铀。该方法是基于铀-均苯四甲酸（苯-1，2，4，5-四羧酸）络合物吸附积累到悬汞滴电极上，然后通过使用差分脉冲调制的伏安扫描还原吸附物种。研究了pH值、均苯四甲酸浓度、富集电位和富集时间等因素对灵敏度的影响。峰电流与U（IV）浓度成正比，最高可达40 ng mL−1，检测限为0.136 ng mL−1，累积时间为120 s。线性范围提高到71.4 ng mL− 1，检测限提高到0.058 ng mL− 1，累积时间分别为60 s和300 s。10次重复测定4.76 ng mL−1 U（IV）的相对标准偏差等于2.7%。研究了主要阳离子和阴离子可能产生的干扰。方法用于分析纯盐、海水及与铀合金相应的合成样品中铀的测定，结果满意。
A very sensitive and selective adsorptive cathodic stripping procedure for trace measurement of uranium is presented. The method is based on adsorptive accumulation of the uranium-pyromellitic acid (benzene-1,2,4,5-tetracarboxylic acid) complex onto a hanging mercury drop electrode, followed by reduction of the adsorbed species by voltammetric scan using differential pulse modulation. Influences of effective parameters such as pH, concentration of pyromellitic acid, accumulation potential and accumulation time on the sensitivity were studied. The peak current was proportional to the concentration of U(IV) up to 40 ng mL−1 with a limit of detection of 0.136 ng mL−1 with an accumulation time of 120 s. The range of linearity enhanced to 71.4 ng mL−1and the detection limit improved to 0.058 ng mL−1with accumulation times of 60 s and 300 s respectively. The relative standard deviation for 10 replicate determination of 4.76 ng mL−1 U(IV) was equal to 2.7%. The possible interference by major cations and anions are investigated. The method was applied to the determination of uranium in some analytical grade salts, seawater and in synthetic samples corresponding to some uranium alloys with satisfactory results.