在聚乙烯醇(PVA)存在下铱-钼酸盐-罗丹明B缔合显色反应的研究及应用  

A Study on the Color Reaction of the AssociatedComplex of Iridium( IV) - Molybdate - RbodamineB at the Presence of Polyvinyl Alcohol

作　　者：臧淑艳[1] 王淑坤[1] 

机构地区：[1]辽宁大学化学院,辽宁沈阳110036

出　　处：《辽宁大学学报（自然科学版）》2002年第2期108-111,共4页Journal of Liaoning University：Natural Sciences Edition

摘　　要：研究了在聚乙烯醇（PVA）存在下,铱-钼酸盐-罗丹明B缔合物的超高灵敏显色体系,缔合物的最大吸收位于585nm,摩尔吸光系数∈=1.06×106L·mol-1·cm-1,服从比尔定律范围为0～3.15μgIr/25ml.测定2.0μg铱的相对标准偏差为2.5％（n=7）.测定铱的适宜条件为CHCIO4=0.99mol/L,CMvO42-=8.7×10-4mol/L,CRB=2.9×10-5mol/L,PVA0.5％.试验了近30多种共存离子的影响,用平衡移动法测定缔合物的摩尔比Ir:RB=1:4,初步探讨了反应机理.本方法已用于冶金产品铱的测定,结果满意.A new spectrophotometric method for the determination of iridium has been devel-oped. It is based on the reaction of iridium with molybdate and rbodamine B(RB) to form an ion -associated complex at the presence of polyvinyl alcohol (PVA) . The ion associated complex exhibits maximum absorption peak at 585nm, with an apparent molar absorption coefficent ov 1.06×106L·mol·1 cm-1. Beer's law is obeyed in the range of 0～3.15μg/25mL for Ir (Ⅳ ) . The relative stan-dard deviation of 2. 0μg Ir is 2.5%(n = 7). Over 30 foreign ions were tested for interference. Other noble metal ions Sb( Ⅲ )、Ge( Ⅳ) and Si( Ⅳ) interfered had to be separated from iridium by a fire assay. The optimum conditions for the determination of Ir are 0.99mol·L-1 of HClO4,8.7×10-4 mol·L-1 of MoO42-,2.9×10-5mol·L-1 of RB, 0.5% of PVA. The proposed method was used to determine Ir in some ores and metallurgical products. The molar ratio is established to be Ir:RB = 1:4 by the equilibrium shift method.

关 键 词：聚乙烯醇 PVA 铱 钼酸盐 罗丹明B 缔合物 显色反应 摩尔比 光度法 含量测定 摩尔吸光系数 

分 类 号：O614.825[理学—无机化学] O657.32[理学—化学]