Adsorption of Th (IV) and Ce (IV) on zirconium based metal-organic framework Zr-CAU-24

In this paper, zirconium based metal-organic frameworks (MOFs) Zr-CAU-24 was successfully prepared by using solvothermal method, which was one kind of zirconium based MOFs. Zr-CAU-24 has nanoporous structure with BET specific surface area of 1610 m²/g. Thermogravimetric analysis (TGA) and irradiation stability test were conducted. Taking Zr-CAU-24 as adsorbent, the adsorption characteristics of Th (IV) and Ce (IV) on Zr-CAU-24 were investigated through static adsorption experiments. The effects of contact time, initial pH on Th (IV) and Ce (IV) adsorption by Zr-CAU-24 were investigated respectively, and the kinetics and thermodynamics were investigated. The results indicate that Zr-CAU-24 has good thermal stability and irradiation stability. The quasi-second-order model provides a good explanation for the adsorption process of Th (IV) and Ce (IV) on Zr-CAU-24, which is a chemical adsorption process. The active site of Zr-CAU-24 is evenly distributed, and the adsorption is a single layer adsorption. Through the study of selective adsorption of mixed metal ions on Zr-CAU-24, it is found that Zr-CAU-24 has the adsorption selectivity for Th (IV) and Ce (IV). (authors)