Adsorption of uranium(VI) from aqueous solution using a novel magnetic hydrothermal cross-linking chitosan

The magnetic hydrothermal cross-linking chitosan (HCC-Fe3O4) was prepared by hydrothermal carbonization and was characterized by FT-IR, X-ray diffraction and scanning electron microscopy. The as-prepared HCC-Fe3O4 was used as adsorbent to remove uranium(VI) as functions of contact time, pH, temperature and initial uranium(VI) concentration batch wise. The results indicated that the magnetic HCC-Fe3O4 was favorate for solid-liquid separation and the maximum uranium(VI) adsorption capacity was 263.1 mg/g at pH 7.0 and 25 A degrees C. The adsorption isotherm of uranium(VI) was well fitted by the Langmuir model. The adsorption is a chemical reaction in nature proved by the well described with pseudo-second-order model. The obtained thermodynamics parameters of positive Delta H, positive Delta S, and negative Delta G denoted the adsorption was an endothermic, disorder increasement, and spontaneous process. These results demonstrated that HCC-Fe3O4 was a promising adsorbent for the enrichment of uranium(VI) from aqueous solutions.