Highly efficient capture of rubidium ion by a novel HS-Fe3O4@MIL-53(Al) composite material

Abstract A general synthetic strategy for HS-Fe 3 O 4 @MIL-53(Al) adsorbent has been developed in this work. The composite material exhibits an efficient capture performance for rubidium ion due to sulfhydryl group and magnetic Fe 3 O 4 doped in its porous cavity. The results of X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, and N 2 adsorption–desorption proved that the HS-Fe 3 O 4 was immobilized in the composite material. High Rb + uptake capacity over the HS-Fe 3 O 4 @MIL-53(Al) is attributed to the exchange of acidic protons between the sulfhydryl group and the Rb + . The pseudo-second-order and Freundlich model could make a good description of the adsorption process. The Rb + sorption selectivity was moderately influenced by any co-ions effect (K + , Na + and Cs + ) due to HS-Fe 3 O 4 doped. These results reveal that our novel composite material might be a promising industrial adsorbent for Rb + capture.