| PAM/GO composite,organic-inorganic hybrid PPy/Ti?HPO4?2 and MWCNT-g-VP were prepared by plasma technique and oxidative polymerization. We have studied their application to adsorb radioactive nuclide Sr???, heavy metals ion Cr??? and Pb??? as well as the adsorption mechanism:In the first chapter, the present status and harmfulness of radioactive nuclides,and heavy metal ions as well as some treating methods was totality introduced. The main influence factors on adsorption, the study background, basic content and sketch of experimental scheme were introduced in brief.In the second chapter, the PAM/GO composites are successfully synthesized, which are further applied to remove Sr??? from aqueous solution. The adsorption behavior of as-prepared PAM/GO composites wereinvestigatedby batch experiments.The adsorptionprocess depends on contacttime,p H value and ionic strength. Moreover, the adsorption kinetic process follows the pseudo-second-order and the Langmuir model. Thermodynamic data suggest that the adsorption of Sr??? on PAM/GO composites is a spontaneous and endothermic process. The fast and efficient adsorption performance indicates that PAM/GO composites could be potentially used as an effective materialfortheremovalof Sr???from aqueoussolutions.In the third chapter, An efficient organic-inorganic hybrid material of Cr??? adsorbent,PPy/Ti?HPO4?2 composites, was successfully synthesized by utilizing an oxidative polymerization technique. The adsorption process of the as-prepared PPy/Ti?HPO4?2 composites toward Cr??? was investigated by batch experiments, which was found to be p H and ion strength dependent. Lower p H values and ion strengths faciliated the adsorption process. The adsorption kinetics fitted well with a pseudo-second-order kinetic model and the Langmuir isotherm gave better simulation than the Freundlich isotherm, indicating a monolayer coverage of Cr??? on PPy/Ti?HPO4?2 surface.Thermodynamic data were also obtained by time-dependent adsorption isotherms, suggesting an endothermic and spontaneous process. The as-prepared PPy/Ti?HPO4?2 hybrid might provide a promising candidatefortheseparationof Cr???fromaqueoussolutionsin realwatertreatment.In the fourth chapter, we grafted VPon MWCNTs by using plasma technique.According to theXRD and XPS analysis, VP are grafted on the framework of MWCNTs and are replayed the hydroxyl groups and carboxyl groups on MWCNT surfaces. The VP grafted on the surface of MWCNT-g-VP can prevent MWCNT-g-VP entanglement and can provide more functional groups,and then promotes the sorption of Pb??? on MWCNT-g-VP obviously. The p H dependent Pb???sorption on MWCNT-g-VPsuggests that the sorption of Pb??? is mainly dominated by inner-sphere surface complexation. The pyridyl groups on MWCNT-g-VP are crucial for the immobilization of Pb??? ions from aqueous solutions. From the results, MWCNT-g-VP is a promising material in the removalofheavymetalionsfromwasterwater.Based on the different adsorption performances of metal ions on different adsorbents absorption mechanisms have been investigated. The results will provide theoretical bases and experimental date fortheassessmentand treatmentin thecontrolofradioactive nuclidesandheavymetalions. |
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