双波长分光光度法同时测定含铑、金、硒、碲冶金物料中铂、钯的研究

Dual-Wavelength Spectrophotometric Method for Simultaneous Determination of Platinum and Palladium in the Presence of Selenium, Tellurium, Gold and Rhodium

针对铑、金、硒、碲严重干扰用二苄基二硫化乙二酰胺(DbDO)为显色剂测定铂的问题,研究用碘化钾和抗坏血酸作还原剂,以双波长分光光度法同时测定铂、钯.在2～3mol/L HCl中,铂、钯—DbDO配合物经萃取显色,三氯甲烷萃取液经>8mol/L HCl洗涤后,配合物颜色稳定,吸光度恒定可获得最大值.钯用双波长等吸收波长法(λ_2=454nm,λ_1=548.5nm),铂用双波长倍率系数法(λ_2’=521nm,λ_1’=500nm,K=2.521).

In order to overcome the interference of Se, Te, Au and Rh in the determination of Pt by dibenzylthio-oxamide (DbDO)dual-wavelength spectrophotoiretric method for simultaneous determination of platinum and palladium has been performed using potassium iodide and ascorbic acid to replace SnCl2 as reducing agent for Pt(IV)to Pt ( II ). It is stcvn that colcured cirplexes of Pt and Pd can be separated by extraction with chloroform from a large amount of Rh in the 2-3 mol/L HCI medium. Dual-wavelength spectrophotoiretric melted is u:ed fcr the c'eterir irstion of platinum and palladium,the measuring wavelength and reference wavelength teirg 521 nm ard 500 nm(K -2.521) for Pt, 454 nm and 518.5 nm. for Pd .respectively. Satisfactory results can be obtained with the ratio-of platinum and palladium from 10 : 1 to 1 : 10.