Efficient Adsorption of Rh(III) from HNO3 Solution on Ion-exchange Resin Bearing N,N,N-Trimethylglycine by Adding N Donor Ligands and Desorption Using Thiourea

Abstract

Abstract To recover Rh(III) from HNO3 solution, adsorption experiments have been performed using an ion-exchange resin bearing an N,N,N-trimethylglycine group (AMP03). AMP03 was found to exhibit relatively high adsorption ability for Rh(III) for [HNO3]surp < 0.02 M ([HNO3]surp denotes HNO3 concentration in the supernatant), and the Kd values increase significantly with the addition of triethylamine or tris(2-aminoethyl)amine to 0.12 M HNO3 solutions. In contrast, the addition of thiourea leads to a decrease in the Kd values; i.e., a masking effect on Rh(III) was observed. These results show that AMP03 has a significant potential for effectively recovering Rh from HNO3 solution.