对碘偶氮氯膦用于微量铂系元素测定的应用研究.PDF

2006 3 Mar. 2006 27 1 Precious Metals Vol. 27, No. 1 730010 Determination of Platinum Group Metals with Chlorophosphonazo-pI LIU Xilin, LI Xin, KOU Zongyan ( The Science and Engineering College, Gansu Lianhe University, Lanzhou, Gansu 730000, China ) Abstract: In this paper, five catalytic spectrophotometric methods based on the catalytic effect of platinum group metals on the oxidations of chlorophosphonazo-pI with KIO (KBrO ) in acidic 4 3 medium were proposed for the determination of trace Ru, Rh, Os, Ir and Pt. At the same time, the colouration reaction between palladium and chlorophosphonazo-pI was studied, too. It was found that palladium reacts with chlorophosphonazo-pI to form a 1:1 blue complex in H2SO4 medium. The methods proposed in this paper have been applied to the determination of platinum group metals in ores and catalysts with satisfactory results. Keywords: Analytic chemistry; Platinum group metals; Chlorophosphonazo-pI; Spectrophotometry; Catalytic spectrophotometry RuRhOsIrPt KIO (KBrO ) 5 4 3 O657.3 TG146.3 A 1004-0676(2006)01-0038-04 [2-(2--4-)-7-(4-)-1,8--3,6-] [1]RuRhOsIrPt (KIO 4 KBrO [2] -5 3) 10 -6 10 g/L5 [3 4] 4 ( -60) = 3 6 10