Sorption-atomic emission determination of platinum and palladium in technological solutions using Lewatit AF5 sorbent

A method for determining platinum and palladium in technological solutions of refining production by inductively coupled plazma atomic emission spectrometry (ICP AES) with preconcentration on a synthetic carbon sorbent has been developed. Platinum metals content in such solutions in lower than detection limit of direct ICP-AES determination (~0,1 mg/dm 3 ). The values of the dynamic exchange capacity (DEC) for the sorption concentration of platinum and palladium from technological solutions have been found. Depending on the type of solution for platinum, the DEC is 0.7 – 1.6 × 10 –3 mg/g, and for palladium 0.7 – 0.9 × 10 –3 mg/g. Based on the DEC values, an effective sorbent weight (155.9 g) was calculated for concentrating platinum and palladium. To concentrate platinum and palladium the test solution is passed through a column with sorbent for 4 h, then analytes are eluted with aqua regia for ICP-AES determination. The recovery of platinum at the stage of sorption concentration is 98.7 – 99.3%, and palladium 98.9 – 99.7%. The elution degree is 98.7 and 98.8%, respectively. To estimate the accuracy of the proposed technique the model solutions with different platinum metals content were also analysed by inductively coupled plasma mass spectrometry (ICP MS). The results obtained by two methods are comparable that allows to recommend sorption-atomic emission technique as a less expensive alternative to ICP MS for determination of Pt and Pd trace contents in technological solutions of refining production.