The Adsorption Application Research Of Molecular Assemblied Chitosan Polyamine-diatomite Materials To Uranium, Strontium And Cesium

Nowadays, as the large emission of radioactive waste water has endangered humanhealth, people’s demand for the safe and effective technology to treat radioactive wastewater and residues is coming even more urgent. The chitosan polyamine-diatomite as anew type of radionuclide adsorbent, is nontoxic, biodegradable and will not causesecondary pollution to environment. Thus this kind of material has a potential applicationvalue to radioactive pollution abatement and may become a newly environmentalabsorbent material to radionuclide.This work is focused on the treatment of uranium, strontium and cesium ions inradioactive waste water. The synthesis technics of these materials and their application inthe adsorption of uranium, strontium and cesium ions are explored. The main work is listedas follows:Using the uranium, Sr, Cs ions imprinting technology, the organic chitosan are graftedto the surface of purificatied diatomite and bentonite. The marked uranium, strontium andcesium chitosan polyamine-diatomite materials and chitosan polyamine-bentonitematerials are assembled and synthesized. And these materials are characterized byscanning electron microscope, FT-IR and X-ray EDS. The adsorption performances ofchitosan polyamine-diatomite materials and chitosan polyamine-bentonite materials touranium, strontium and cesium ions in water were discussed, including the effect factors ofpH value, absorbent dosage, the initial concentration of uranium, strontium, cesiumsolution, adsorption temperature and adsorption time. Furthermore, the adsorption isothermtype of the materials to uranium, Sr, Cs ions, and the adsorption processes dynamic modelare also researched. The experimental result shows that the chitosan polyamine-diatomitematerials show a preferably adsorption capacity for uranium, strontium and cesium ions,and the adsorption can be balanced in a relatively short time and have a good selectivity. Inthe adsorption processes, the adsorption of chitosan polyamine-diatomite materials for uranium accords with the Freundlich adsorption isotherm model, whereas the adsorptionfor cesium corresponds to the Langmuir adsorption isotherm model. Adsorption time is acrucial factor for the adsorption behavior of chitosan polyamine-diatomite materials touranium, strontium and cesium ions. Herein, the adsorption processes of chitosanpolyamine-diatomite materials and chitosan polyamine-bentonite materials to uranium,strontium and cesium ions all obey the second-order reaction kinetics model. To someextent, this study will provide certain theoretical and experimental basis for these new typeof chitosan polyamine-diatomite materials for the radioactive waste water treatment.