Study On Removal Of Heavy Metal And Iodine Ions Onto Various Adsorption Materials

Adsorption is a highly effective way to treat heavy metal and nuclear wastewater. Furthermore, exploiting a new valid low-cost adsorbent is a hot research topic in the recent years. In order to provide the basis for treating heavy metal and nuclear wastewater, the adsorption of tremolite, modified bentonite, modified active carbon and graphene to heavy metal and simulated nuclear ions were studied in the thesis.1. Tremolite was characterized and studied for the removal of Pb2+ion from aqueous solution through batch equilibrium experiments. Its surface and structure were analyzed by SEM and XRD. To highlight their application and effects on absorption, pH, adsorption time, adsorption temperature and initial concentration were investigated. Adsorption behavior of Pb2+ion was approximately follows described with the Langmuir model and pseudo-first order kinetic model. The thermodynamic parameters (△G°,△H°and△S°) were also determined, and the process of the adsorption is exothermal, spontaneous, ordered degree increased.2. Modified bentonite was characterized and studied for the removal of Co2+and Mn2+ions from aqueous solution through batch equilibrium experiments. Its surface and structure properties were analyzed by SEM and XRD. To highlight their application and effects on adsorption temperature, initial metal concentration and the effects of paratoluic acid are investigated. Adsorption behaviors of Co2+and Mn2+ions were approximately follows described with the Langmuir model.3. Modified active carbon was characterized and studied on the removal of I-ion from aqueous solution through batch equilibrium experiments. Its surface was analyzed by SEM. To highlight their application and effects on dosage of modified carbon, pH, adsorption temperature and initial metal concentration are investigated. Adsorption behavior of I-ion was approximately follows described with the Langmuir model. The thermodynamic parameters (△G°,△H°and△S°) were also determined, and the process of the adsorption is exothermal, spontaneous, ordered degree increased.4. Graphene was characterized and studied on the removal of Cs+ion from aqueous solution through batch equilibrium experiments. Graphene is prepared by different methods and analyzed by SEM and XRD to investigate its surface and structure properties. Ammonium citrate is a good reducing agent in preparing grapheme, and graphene is a kind of good adsorbent for Cs+ion, and the adsorption capacity is97.49mg/g.