Reversed phase extraction chromatographic separation of palladium(II)using liquid anion exchanger

摘要

A selective, sensitive, less expensive and more precise method has been developed for separation of palladium(II)with N-n-octylaniline, coated on silica gel as a stationary phase. Quantitative extraction of palladium(II) is observed inthe acidic medium within the range 0.8-1.2 M nitric acid with 1.5% N-n-octylaniline at a flow rate of 0.5 ml /min. Theextracted metal ion is striped with 7.0 M ammonia and determined by spectrophotometric method. The extractionbehaviour of palladium(II) has been studied as a function of different parameters such as concentration of mineral acids,reagent, eluation time and diverse ions. The method is free from large number of cations and anions. It is applied forseparation of palladium(II) from synthetic mixtures corresponding to alloys. A scheme for mutual separation ofplatinum(IV), palladium(II) and iridium(III) has been developed. Log-log plot of N-n-octylaniline concentration versusdistribution ratio indicates that probable extracted species is [RR NH_2~+Pd(NO_3)_3]org.