Determination of palladium in palladium oxide by EDTA titration with hydrazine hydrate reduction
WANG Yan-hong1, GONG Jia-chen1, ZHANG Rui-feng2
1.Shenyang Research Institute of Nonferrous Mentals,Shenyang 110141,China; 2.Material Science﹠Engineering Institute,Xi′an Jiaotong University,Xi′an 710049,China
Abstract：The palladium oxide was hardly dissolved by the common acid method. In proposed study, the palladium oxide was reduced to the metal palladium black in supernatant solution at 80 ℃ using hydrazine hydrate as reducing agent. After filtration, the metal palladium black with filter paper was treated by carbonization with hydrochloric acid and nitric-sulfuric acid. The palladium was introduced into solution, solving the sample preparation problem of indissolvable palladium oxide. Then, the excessive EDTA was back-titrated with zinc salt in HAc-NaAc buffer solution at pH 5.8 using xylenol orange as indicator. The equal amount of EDTA to palladium was precipitated with dimethylglyoxime. The dimethylglyoxime-palladium precipitate was extracted with trichloromethane. The precipitated EDTA was titrated with zinc salt to determine the content of palladium. Thus, the determination method of palladium in indissolvable palladium oxide by EDTA titration with hydrazine hydrate reduction was established. The content of palladium in actual sample was determined according to the experimental method. The relative standard deviations (RSD, n=5) were between 0.12% and 0.20%. The proposed method was also applied to the determination of palladium in certified reference material of palladium oxide, and the found results were consistent with the theoretical values.
魏小娟,刘秋香,谢智平,等.电感耦合等离子体原子发射光谱法测定废钯碳催化剂中钯[J].冶金分析,2014,34(11):32-36.WEI Xiao-juan,LIU Qiu-xiang,XIE Zhi-ping,et al.Determination of palladium in waste palladium-carbon catalyst by inductively coupled plasma atomic emission spectromet[J].Metallurgical Analysis,2014,34(11):32-36.
[9]
黄瑶,沙娇,徐莲,等.Pd/C催化剂及其冶金废料分解和测定的研究[J].贵金属,2014,35(1):70-74.HUANG Yao,SHA Jiao,XU Lian,et al.Research on dissolution and determination for Pd/C catalyst and its metallurgy waste[J].Precious Metals,2014,35(1):70-74.
[10]
朱利亚,赵忆宁,金娅秋,等.金、银、铂、钯合金中钯的选择性滴定方法的研究与应用[J].贵金属,2007,28(2):40-44.ZHU Li-ya,ZHAO Yi-ning,JIN Ya-qiu,et al.Research and application of the method for selective titration of Pd in Au,Ag,Pt,Pd alloys[J].Precious Metals,2007,28(2):40-44.
[11]
王艳红,宫嘉辰,陆小娟.丁二酮肟沉淀钯-EDTA滴定法测定富钯物料中的钯[J].有色矿冶,2011,27(5):53-54.WANG Yan-hong,GONG Jia-chen,LU Xiao-juan.Dimethylglyoxime precipitate palladium-determines palladium in the rich palladium material by EDTA titrimetric method[J].Non-ferrous Mining and Metallurgy,2011,27(5):53-54.
