共振瑞利散射光谱法测定痕量金

Resonance Rayleigh-scattering spectrometric determination of trace gold

在聚乙烯醇(PVA)存在下,Au(Ⅲ)与钨酸盐及番红花T形成离子缔合物,在328nm处产生强烈的共振瑞利光散射现象,据此建立了一个测定金的新方法。研究了该体系的最佳反应条件。在优化的条件下,Au(Ⅲ)的质量浓度在0.48～2.88ng/mL范围内与散射光增强强度(ΔI)具有良好的线性关系,方法的检出限为0.016 96ng/mL。大量存在的常见离子对Au(Ⅲ)的测定不干扰。本法用于砂矿和炭粉中金的测定,结果与原子吸收光谱法(AAS)吻合,相对标准偏差(n=5)≤4.1%。

In presence of polyvinyl alcohol（PVA）,Au（Ⅲ） could react with tungstate and crocus T to form ionic associate,which had strong resonance Rayleigh scattering at 328 nm.Based on this phenomenon,a new determination method of gold was established.The optimal reaction conditions of this system was studied.Under the optimized conditions,the mass concentration of Au（Ⅲ） in range of 0.48-2.88 ng/mL showed good linearity to the enhanced intensity of scattering light（ΔI）.The detection limit of method was 0.016 96 ng/mL.The presence of a large amount of common coexisting ions had no interference with the determination of Au（Ⅲ）.The proposed method was applied to the determination of gold in placer and carbon powder,and the results were consistent with those obtained by atomic absorption spectrometry（AAS）.The relative standard deviation（RSD,n=5） was less than 4.1 %.