| Recent years, a new effective separation technique, molecular imprintingtechnique has been developed rapidly, also, it has the promising uses in bio-medicine,separation and purification and preparation, utilization of circulative resources andenvironmental checks. In this papers, those novel Ce3+ion imprinted materials whichuse PEI or chitosan as functional monomer were desiged and synthesized by surfaceion imprinting technique, and then the product structure were characterized andanalyzed. Futhermore, the optimize synthesis process were studied and the adsorptionproperty of Ce3+ion imprinted materials were investigated.Fristly, the structure design of Ce3+surface imprinted polymer was made byconductivity titration experiments, UV scanning analysis and structural analysis. Theappropriate functional monomer of Ce3+surface imprinting thing was experimentallydetermined for PEI molecules; and ECH was ring crosslinking agent. By singleelement experiments, Ce3+-PEI surface imprinted polymer’s the optimal synthesiswas obtained, which was under the condition of5g activated silica gel particles asbasic materials,7.5mL CP and2.5g PEI was used, and a large molecular weight (2wabove) the PEI molecules as functional monomer, ECH closed loop as a crosslinkingagent. The characterization results of Ce3+surface imprinting materials weredescribed that Ce3+-PEI surface imprinted polymers existed "ligand hole", SiO2functional monomer grafted PEI, and maintained a certain degree of crystallinity.Secondly, static adsorption characteristics of Ce3+-PEI surface imprintedpolymer were experimentally studied. The results showed that the best adsorption pHwas5.5; adsorption capacity increased with increasing temperature; and adsorptionrate gradually decreased over time at the same temperature until it reachedequilibrium; experimental temperature (15℃-35℃) adsorption equilibrium costabout2.5h. Moreover the Freundlich isotherm equation of Ce3+surface imprintedobject for Ce3+was conducted. The results showed that the adsorption process fit inwith Freundlich isotherm equation well and was an endothermic process, equationcoefficients Kf increases with increasing temperature, while the value of ‘n’ is greaterthan1, and the adsorption process is "preferential adsorption" Thirdly, the synthesis methods of Ce3+-chitosan imprinted polymer werepreliminarily discussed. The optimized Ce3+-chitosan imprinted polymer processconditions was experimentally stuided, and the adsorption effect of prepared Ce3+chitosan imprinted was better while petroleum ether used as the oil phase solvent, theamount of ultrapure water was20mL, oil compatibility dose was75mL, and chitosanwas0.5g. Then the chitosan-Ce3+blotting membranes was parpared, while theglycerol used as a cross-linking agent in the preparation of chitosan-Ce3+blottingmembrane, the surface appearance is better.In the research papers, molecular imprinting technique is applied in theseparation field of rare earth elements, so we can prepare the rare earth elementsimprinted polymer adsorption whose separation factor is high and the effect ofselective adsorption is great, and achieve its efficient enrichment, preferablyseparated. In short, research papers have certain significance to the advancement ofChina’s rare earth resources and environmental protection. |
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