Study On The Uranium Adsorption By Metal Organic Frameworks And Their Derivatives

Uranium and its compounds not only play an important role in nuclear power,but also play a very important role in the fields of military,industrial,agricultural production,science and technology.Nuclear power has brought us convenience,but also increased water and environmental pollution and serious harm to human bodies.In order to respond to the national environmental protection,efficient and clean materials have attracted more and more attention.Therefore,it is of great significance to explore highly effective adsorbent materials to adsorb uranium.In order to solve this problem,this paper explores metal organic framework(MOFs)and their derivative materials for the adsorption applications of uranium from aqueous solutions.The following research results have been obtained:1.Hollow Co₃S₄derived from ZIF-67 was explored to remove radioactive uranium from aqueous solutions.The equilibrium adsorption data were well fitted by the Langmuir model and the high maximum adsorption capacity of 863.71 mg g^-1was obtained at p H?5.0.The result of adsorption kinetics revealed that hollow Co₃S₄can adsorb uranium very rapidly.The study of the reusability by applying adsorption-desorption cycles was also conducted and shows that the hollow Co₃S₄possesses good stability with insignificant capacity decrease after four cycles.In addition,the hollow adsorbent exhibited high removal efficiency in both deionized water and tap water,which indicates a promising potential for applications in efficient extraction of uranium from aqueous solution.2.The manufacture of some MOF-based hollow structural materials is of great significance for achieving high adsorption and removal of uranium.Two hollow structures of ZIF-8 were used for separation uranium from aqueous solutions.Both hollow ZIF-8 showed higher uranium adsorption capacity than traditional ZIF-8.This work provides prospects for the application of hollow MOFs to uranium adsorption.3.This section uses classic ZIF-8 as an adsorbent to study the effect of size on uranium adsorption performance.The results show that under the same conditions,ZIF-8 with different sizes can quickly adsorb uranium,the smallest one(?50 nm)has the best adsorption performance and has good usability after at least four adsorption-desorption cycles.