Adsorptive Separation of Palladium from a Simulated Nuclear Waste Solution with Activated Carbon Fibers

Abstract

Adsorptive separation of palladium from a nitric acid solution was performed by using a pitch‐based activated carbon fiber modified with NaOH (NaOH‐ACF). The NaOH‐ACF showed a markedly improved adsorption performance for the palladium ions as compared with the untreated ACF. It also showed a much higher preferential adsorption for the palladium ion over the rhodium and rhenium ions. The equilibrium capacity of the NaOH‐ACF for palladium was 1.25 meq · g−1. The breakthrough behavior obtained by using the bed packed with the NaOH‐ACF showed a complete separation of palladium from the coexisting ions of rhodium and rhenium. The spent bed was eluted effectively with nitric acid and a palladium nitrate with a purity of higher than 99% could be recovered.