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

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).

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

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.