钼(V)-硫氰酸盐-灿烂甲酚蓝-聚乙烯醇体系共振瑞利散射法测定痕量钼

Determination of Trace Amounts of Molybdenum with Mo(V)-SCN-BCB-PVA Systems by Resonance Rayleigh Scattering Method

研究了在聚乙烯醇（PVA-124）存在条件下钼（V）与硫氰酸根和灿烂甲酚蓝（Brilliant Cresyl Blue，BCB）染料形成离子缔合配合物的共振瑞利散射（RRS）光谱．考察了它们的光谱特性，影响因素和适宜的反应条件，确定了共振瑞利散射强度与钼（V）浓度之间的关系．在酸性条件和PVA-124存在下，钼（V）的配阴离子[Mo（SCN）5]^2-与BCB形成离子缔合物[BCB]2[Mo（SCN）5]，其RRS显著增强．基于RRS的增强，建立了一种测定钢铁中痕量钼（V）的新方法．Mo^5＋的浓度在0～1．2μg／25mL范围内与分析信号具有良好的线性关系（r=0．994），检出限为1．7pμg／L方法应用于钢铁中痕量钼的测定获得满意的结果．

Studies on the resonance Rayleigh scattering （RRS） spectra of the ion-association complexes of EMoO（SCN）5]^2- were carried out with the Brilliant Cresyl Blue（BCB） in the presence of PVA-124. The spectral characteristics,the effect factors and the optimum reaction conditions have been investigated. The quantitative relation between the intensity of RRS and the concentration of molybdenum was established. Due to the increased intensity of RRS with the formation of [BCB]2[Mo（SCN）5] ,a new method of determination of molybdenum was established. The enhanced intensity of RRS was directly proportional to the concentration of Mo（ Ⅵ ） in the range of 0- 1. 2 μg/25mL with the detection limit of 1.7 μg/L. The method was applied to determination of molybdenum（ Ⅵ ） in steel with satisfactory results.