在pH值为5.00的NaAc-Hac缓冲体系中,Nd(Ⅲ)与7-碘-8-羟基喹啉-5-磺酸(FERRON)及溴化十六烷基三甲铵(CTMAB)反应形成三元配合物,最大吸收位于389.5 nm处,Nd(Ⅲ)浓度在0.2～4.0 mg/L范围内服从比耳定律,回归方程为:ΔA=0.1205C+0.0052,r=0.9996(ΔA为试验溶液吸光度Ai与空白溶液吸光度Ao之差; C单位为mg/L Nd(Ⅲ)),表观摩尔吸收系数ε389.5=1.8×10L/(mol·cm),RSD=5.0‰(n=8),检出限为0.083 mg/L.三元配合物的组成比为:Nd(Ⅲ):CTMAB:FERROn=1:2:2.考察了20多种共存离子的影响,大多数常见离子不干扰.用于样品回收实验,结果满意.
Neodymium(Ⅲ) reacted with 7-lodo-8-hydroxyquinoline-5-sulfonic acid and cetyl-trimethylammonium bromide to form a associated complex in NaAc-HAc(pH=5.00) buffer solution. The apparent molar absorptivity of the associated complex was found to be 1.8×104 L/(mol·cm) at 389.50 nm. In the range of 0.2 to 4.0 mg/L, Neodymium(Ⅲ) obeyed Beer's law. The linear regresion equation was ΔA=0.1205C+0.0052, r=0.9996. Where C is mg/L of Neodymium(Ⅲ). The RSD for the determination of 2 μg/ml of Neodymium(Ⅲ) was 5.0‰(n=8).The molar ratio of Neodymium(Ⅲ) to cetyl trimethylammonium bromide to 7-lodo-8-hydroxy-quinoline-5-sulfonic acid in association complex was establish to be 1:2:2.The influence of 20 diverse ions was examined. Most common ions did not interfere.The method was proved to be satisfactory for the determination of Neodymium(Ⅲ) in recovery.