Incorporation of phytic acid modified covalent organic polymers into gellan gum-chitosan gel network for selective adsorption of uranium: an experimental and DFT study

The extraction of uranium from strong acidic radioactive wastewater is vital and challenging to sustainable development of nuclear energy. In order to improve the selective uranium adsorption, a phytic acid decorated multiple hydorgel network (MA-U-PA/GG-CS-Ca) was constructed by incorporating phytic acid modified covalent organic polymers to gellan gum and chitosan hydrogel by supramolecular self-assembly. The results indicated that the selectivity ratio (SU) of MA-U-PA/GG-CS-Ca for uranium adsorption increased from 28 to 72%. The adjacent –P = O groups within the phytic acid molecule reduces the free energy of the coordination reaction with uranium, which is favorable to the uranium adsorption under acidic condition.