The Synthesis Of ?-cyclodextrin Pseudo-polyrotaxane And The Study Of Adsorption Properties For Thorium

?-cyclodextrin??-CD?is a cone-shaped cyclic oligosaccharide consisted of seven D-glucopyranose,which has different sizes of hydrophobic cavity,hydrophilic outer surface and chirality.?-CD has been widely applied in many fields of environmental protection,polymer,analytical chemistry and medicine.However,the bonding effect of natural cyclodextrins and substrate molecules is relatively weak,which limited the application of them.In order to improve the application value of natural cyclodextrins,it is necessary to carry out some chemical modification to natural cyclodextrins.In recent years,bridging cyclodextrins and cyclodextrins inclusion studies have flourished,the polypseudorotaxane based on?-cyclodextrin as a special cyclodextrin inclusion compound.The physical and chemical properties of guest molecules can be altered by the excellent properties of the clathrate and can be linked to multiple cyclodextrin rings.The study of Cyclodextrins polypseudorotaxane has become a hotspot in the field of supramolecular chemistry,widely used in tissue engineering scaffolds,human bio-sensors,molecular machines and drug control release carrier and other intelligent bio-materials.Therefore,this paper studied a new kind of special function of?-cyclodextrin inclusion complexes,including the preparation and the study of the material on the adsorption application of Th?IV?.The main parts of the paper include the following three aspects:1.Thorium and?-cyclodextrin was brief overview,and the application of cyclodextrins inclusion complex and the synthesis of polypseudorotaxane the factors influencing the synthesis of polypseudorotaxane and the functi-onal application were summarized.The main research contents of thissubject was put forward.2.The adsorption of thorium was studied using a polypseudorotaxane,which was obtained by the reaction of PPG-NH₂ and?-CD.IR,¹HNMR and TG was used to analyze the experimental materials to confirm the reliability of the synthetic material,The adsorption of were examined as a function of the contact time?pH and adsorbent dose using batch adsorption experiments.The experimental results showed that the optimum conditions were as follow:pH=3.5,contact time is 80 min and adsorbent dose is 20mg.The equilibrium adsorption capacity were found to be 11.13mg g^-1.The result showed that the polypseudorotaxane based on?-cyclodextrin has a certain adsorption capacity,Which has laid a foundation for further investigation of the polypseudorotaxane adsorbed thorium synthesized by?-cyclodextrin.3.The adsorption of thorium was studied using a polypseudorotaxane,which was obtained by the reaction of PPG and?-CD-6-OTs.The adsorption of were examined as a function of the contact time,p H of the solution,adsorbent dose,concentration of thorium and temperature using batch adsorption experiments.The experimental results suggested that the optimum conditions were found to be at pH 4.0,contact time 40min,20mg L^-1 Th?IV?concentration and 298K.The equilibrium adsorption capacity were found to be 15.36 mg g^-1.When the concentration of Na⁺,Mg²⁺,Fe³⁺,Zn²⁺and Ni²⁺,sorbent can effectively adsorb Th?IV?ion.It was clear that the pseudo-second-order model described better with a slightly higher correlation coefficient?R²=0.997?in comparison with that of the pseudo-first-order model?R²=0.847?.The process of adsorbing thorium by the polypseudorotaxane based on?-cyclodextrin is the adsorption of monomolecular layers that occur on the surface of the adsorbent.The Langmuir isotherm model fit with the experimental data better than The Freundlich isotherm model.The thermodynamic parameters were calculated,the result showed that the adsorption of Th?IV?is exothermic and spontaneous process.