Synthesis And Adsorption Properties Of Imidazolium Salt-Based Porous Ionic Organic Network

Porous Ionic Organic Networks（PIONs）are newly emerging organic porous polymers with the advantages of low density,good physicochemical stability,large specific surface area and adjustable function.Their chemical property,functional groups,and active sites can be easily modified through screening of building blocks and ionic tectons.PIONs have excellent performance in gas storage,water treatment,catalysis,electrochemistry and other related fields due to their high charge density and electrostatic action.This dissertation mainly focuses on the design and synthesis of Ionic Organic Networks and their applications in the fields of adsorption application.It mainly includes two sections as following:First:Synthesis of Imidazole-Based Porous Hypercrosslinked Ionic Oraganic Networks.A series of imidazole-based Hypercrosslinked Ionic Oraganic Network has been successfully prepared based on 2,4,5-Triphenylimidazole（TphIm）with different cross-linking agents through the Friedel-Crafts alkylation.The gas adsorption test results show that HCPs have outstanding specific surface area and rich microporosity.In order to explore the advantages in CO₂ and dye adsorption of ionic liquid functionalized adsorbents,we compare ionized samples and non-ionized sample.As a result,IL moiety increase the affinity between material backbone and molecules.The adsorbent has a significant adsorption capacity of CO₂ molecules and anionic dyes.The ionized sample has the highest methyl orange adsorption capacity of 2587 mg g^-1 and the highest methylene blue adsorption capacity of 156 mg g^-1.The ionized sample shows CO₂ uptake up to 71.6 cm³·g^-1 and 44.9 cm³·g^-1（at 273 K,298K 1 bar）.At 298 K,the ionized sample has the highest selectivity of CO₂/N₂（142/1）.Second:Synthesis of Poss-Based Porous Ionic Organic Networks.Combining the advantages of porous polymer and cage silsesquioxane（POSS）,the octaaminophenyl cage silsesquioxane Porous Ionic Organic Networks was synthesized by taking advantage of the Debus–Radziszewski reaction to obtain PIONs following click-chemistry principles.The materials have imidazole cationic backbone.A porous ionic organic network with different anions was prepared by ion exchange.The influence of Ac^-（CBCP-Ac）and BF₄^-（CBCP-BF₄）in polymers on CO₂ adsorption performance was studied.The results show that the specific surface areas of CBCP-Ac and CBCP-BF₄ are 108 cm²·g^-1 and 81 cm²·g^-1,respectively,and the heat of adsorption of CO₂ is 27.4 kJ·mol^-1 and 23.0 kJ·mol^-1,respectively.CBCP-Ac has a outstanding specific surface area and heat of adsorption.Therefore,the adsorption performance of CBCP-Ac in CO₂ adsorption at 273 K and 298 K is higher than CBCP-BF₄.CBCP-Ac has a stronger interaction with CO₂.