Two New Covalent Organic Frameworks Which Can Adsorb Carbon Dioxide,Dyes And Iodine

Covalent organic frameworks（COFs）as crystalline porous organic polymer material composed mainly of light elements（mainly H,B,C,N and O）are connected by covalent bonds.Because of their periodic ordered pores,high specific surface area,adjustable skeleton structure and functional groups,good thermal and chemical stability,COFs have great potential in various applications such as heterogeneous catalysis,adsorption and separation,energy storage.With the rapid development of human in industry,a huge amount of carbon dioxide to the sun’s long wave radiation absorption,but also can strongly absorb infrared radiation,causing the greenhouse effect,not only harm the balance of the natural ecosystem,but also for a serious threat to the safety of the earth life system,has become one of the current global problems.In addition,with the development of dyeing industry,the wastewater with dyes has become one of the main water pollution sources which is likely to affect human life and health through the food chain directly.As a kind of new energy,nuclear energy has been widely concerned and studied because of its huge development potential and advantages.However with the deepening of the use of nuclear energy,the spent fuel generated constantly accumulates,and the radionuclides contained in it will cause great damage once entering the environment.Therefore,it is necessary to remove the radionuclides produced in the spent fuel and dispose them safely and effectively.Two-dimensional COF materials generally have large specific surface area,and are easy to be designed,modified and synthetized,which are very suitable for large scale production and application,I hope to introduce functional groups in the original COF material,or directly choose functional ligand to synthetize COFs to obtain the corresponding function of two-dimensional COF materials.This thesis mainly includes the following aspects:PartⅠ:I design a new two-dimensional COF by the method of modification,which can not only effectively uptake carbon dioxide but also adsorb cationic dyes.Firstly,I introduce the characteristics of COFs materials,the synthesis method and the existing applications in detail.Then I explain the importance and existing methods of carbon dioxide absorption,dye adsorption and radioactive iodine adsorption.Finally I introduce the meaning of the topic of this thesis.PartⅡ:Firstly,Iintroducehowtosynthesize1,3,5-tris（3-dimethylamino-1-oxoprop-2-en-yl）benzene（TDOEB）,and then illustrate the synthesis of 3-PD and JUC-603 through a new Michael addition reaction principle.After the synthesis of two COF,I test and characterize the structure,crystal,stability,aperture and surface area of these two COFs.Finally,I analyze and compare their capacity of carbon dioxide uptake and dye adsorption capacity.Under the condition of273K and 1bar,the adsorption capacity of JUC-603 to carbon dioxide reached51.7cm³g^-1,which ranked in the forefront of many common COF materials.It also had good adsorption performance on cationic dyes,whose adsorption efficiency reached more than 95%within 2h.PartⅢ:I synthesize a new COF,which can adsorb radioactive iodine through the traditional Schiff base reaction.I synthesize JUC-609 through the Schiff base reaction,and test and characterize the structure,crystal shape,stability,pore size,specific surface area and other aspects of JUC-609 in detail.Finally I analyze the adsorption capacity of JUC-609 to iodine and compare it with other common adsorption materials.JUC-609 is capable of specific adsorption of iodine with a ultimate adsorption capacity of 5.9gg^-1.PartⅣI summarize the content of this paper and discuss the future application prospect of COFs in the environmental field.