W(VI)与Tiron的显色反应及应用  

COLOR-REACTION OF W (VI) WITH TIRON AND ITS APPLICATION

作　　者：陈玉銮[1] 王占文[1] 周向阳[1] 

机构地区：[1]南京化工学院应用化学系

出　　处：《南京化工学院学报》1992年第3期39-43,共5页

摘　　要：研究了W(Ⅵ)与Tiron的显色反应,在pH=4.5的HAc-NaAc介质中,它们形成一种稳定的无色配合物,组成为1:1。该配合物在251nm和312nm处有较强的紫外吸收峰,测得ε_(251)=5.7×10~3,ε_(312)=7.7×10~3,据此建立了测定W(VI)的紫外分光光度法。在251nm和312nm处的线性范围均为2.0×10^(-6)～2.0×^(-4)mol·L^(-1)(0.37～37mg/L),检出限分别为0.37mg/L和0.18mg/L,SiO_3^(2-)及少量PO_4^(3-)的存在不干扰测定,Mo(Ⅵ)、V(Ⅴ)、Fe(Ⅲ)等对测定有干扰,该法试用于几种杂多酸样品的测定,结果满意,方法回收率为95～106％,变异系数≤0.4％(n=5)。Abstract: The color reaction of W(Ⅵ) with Tiron was studied. W(Ⅵ) and Tiron react to form a stable colorless complex with the composition ratio of 1:1 in HAc-NaAc medium (pH=4.5).This complex has two maximum absorption peaks at 251 and 312nm, and their apparent molar absorptivi- ties are 5.7×10~3 and 7.7×10~3 L·mol^-1·cm^-1, respectively. The linear determination ranges are 0.37 to 37 mg/L, and the detection limits are 0.37 and 0.18 mg/L, respectively, with the re- covery ratio of 95 to 106% and the variation coefficient of 0.4% (n=5). It has been satisfactorily applied to the determination of W(Ⅵ) in some heteropolyacid samples.

关 键 词：钨 钛铁试剂 分光光度法 杂多酸 

分 类 号：O614.613[理学—无机化学]