Crown ether-type organic composite adsorbents embedded in high-porous silica beads for simultaneous recovery of lithium and uranium in seawater

The syntheses of crown ether-type organic composite adsorbents embedded in high-porous silica beads for simultaneous recovery of lithium and uranium in seawater have been achieved and the adsorption behavior of lithium and uranium on the composite adsorbents has been examined in several types of original seawater in the wide temperature and pH ranges. As a result, the composite adsorbents composed of benzo-15-crown-5 (BC15) and benzo-18-crown-6 (BC18) showed the top-class maximum adsorption capacities for lithium [6.5 mg/g (BC15), 11 mg/g (BC18)] and uranium [12 mg/g (BC15), 4.2 mg/g (BC18)].