Extraction preconcentration of platinum and ruthenium using high molecularweight amines prior to simultaneous determination by derivative spectrophotometry

Platinum and ruthenium can be simultaneously extracted from hydrochloric ac id solution by high molecular weight amines (trioctylamine (TOA) or diantip yrylmethane (DAM) in 1,2-dichloroethane) after preliminary conversion into the complexes with SnCl3- ligands. The determination of both metals in the presence of each other in organic solutions of the formed ion-pairs can be accomplished by applying derivative spectrophotometry. The values of the se cond derivative spectra at 395 nm and 437 nm, calculated with the: 2-nd deg ree polynomial and 75 points correspond to the concentration of platinum as sociated with TOA and DAM, respectively. The value of the second derivative s at 497 nm and 463 nm can make a basis of the determination of ruthenium i n the presence of platinum in the form of ion-pairs with TOA and DAM. respe ctively. The use of TOA as extractant ensures higher precision and accuracy of the determination of platinum and ruthenium by derivative spectrophotom etry. RSD of the results of the determination of metals in synthetic mixtur es does not exceed 2.7% and 3.2% for platinum and ruthenium, respectively.