Development of 3D porous Ag+ decorated PCN-222 @ graphene oxide-chitosan foam adsorbent with antibacterial property for recovering U (VI) from seawater

In this study, a 3D porous Ag+ decorated PCN-222 @ graphene oxide-chitosan foam adsorbent (APGC foam), which is grounded upon the growth of Ag+ decorated zirconium-metalloporphyrin metal-organic framework (PCN-222) on an EDTA-silane modified graphene oxide-chitosan foam substrate (EGC foam) for recovering U(VI) ions out of the seawater, was designed and synthesized with the in-situ growth and solvothermal method. The successfully synthesized APGC foam with excellent antibacterial property not only overcame the difficulty of powder adsorbents in practical application, but also reduced the negative impact of bacteria on the adsorption performance of porous material. The APGC foam showed excellent adsorption capacity (348.8 mg/g), selectivity and reusability of U(VI) adsorption at nearly seawater pH, and this also exhibited excellent adsorption performances in the seawater. The influence factors in the adsorption process were investigated by static and dynamic adsorption in different conditions. Moreover, the U(VI) adsorption mechanism of APGC foam was determined as the comprehensive effect of coordination, electrostatic interaction and intraparticle diffusion. All results indicated that APGC foam was an encouraging adsorbent to recover U(VI) out of the seawater.

Automated summary

A 3D porous Ag+ decorated PCN-222 @ graphene oxide-chitosan foam adsorbent (APGC foam) was designed and synthesized for recovering U(VI) ions from seawater, showing excellent adsorption capacity, selectivity, and reusability. The mechanism of U(VI) adsorption by APGC foam was found to involve coordination, electrostatic interaction, and intraparticle diffusion, making it a promising adsorbent for U(VI) recovery from seawater.