Adsorptive stripping voltammetric determination of uranium with cephradine

Abstract

Uranium adsorbed with cephradine is reduced on a hanging mercury drop electrode. This property was exploited in developing a highly sensitive stripping voltammetric procedure for the determination of uranium. A detection limit 2 × 10^–9 mol l^–1(0.5 µg l^–1) of uranium ion is obtained with an 180 s accumulation time. Cyclic voltammetry was used to characterize the interfacial and redox behaviour. The effects of various parameters are discussed. Experimental conditions include the use of 5 × 10^–6 mol l^–1 cephradine in 0.05 mol l^–1 sodium perchlorate (pH ≈ 6.5), an accumulation potential of 0.0 V versus SCE and a direct current stripping technique. The response is linear up to 5 × 10^–6 mol l^–1 uranium and the relative standard deviation at 1 × 10^–7 mol l^–1 UO²⁺ is 4.4%. The effect of other metal ions was investigated.