Design,Synthesis,Gas Separation And Catalytic Performance Of Several Amide Functional Modified Porous Coordination Polymers

Porous Coordination Polymers（PCPs）,also known as Metal-Organic Frameworks（MOFs）,are a new class of organic-inorganic hybrid materials,compared to traditional inorganic porous materials.Because such porous materials are easy to synthesize,have a variety of structures,a large number,a large specific surface area and pore volume,and the pore surface is easily functionalized and modified,and particularly,the structure and porosity are easily controlled by the target,so the porous material is in the aspect of adsorption showing great potential for application.At present,fossil fuels,such as oil,natural gas and coal,still dominate the global total energy consumption（above 80%）.Combustion of these fuels inevitably emits large amounts of carbon dioxide,which is considered to be the world’s leading greenhouse gas.Therefore,the development of high CO2 adsorption performance and storage of MOFs is of great significance.In this dissertation,two amide-modified polydentate carboxylic acid ligands,H4L1 and H4L2,were designed and synthesized.Under the certain conditions,two kinds of porous ligands were obtained by self-assembly of the[Cu2（COO）4]secondary structural unit.The polymer materials were named HNUST-6 and HNUST-8（HNUST=Hunan University of Science and Technology）,and the structure,gas storage and catalysis properties of the two PCPs were studied.The results show that HNUST-6 is a material with two interpenetrating structures and can maintain the stability of the skeletal structure after activation,has a specific surface area,good water stability and chemical stability.The material has good adsorption and separation ability for CO2 gas and high catalytic performance;while another HNUST-8 with self-penetrating structure does not collapse after the activation treatment,the material not only has a high specific surface area,but also Keeps the skeleton stable in different acid-base solutions.Under low pressure and high pressure conditions,HNUST-8 exhibits high CO2adsorption,high CO₂ adsorption enthalpy and better CO₂/N₂,CO₂/CH₄ gas adsorption selectivity.In addition,a breakthrough experiment was conducted on HNUST-8 to prove its good gas selectivity.Finally,HNUST-8 also exhibits good catalytic performance.It is indicated that the insertion of polar amide groups in the framework structure of porous coordination polymers can not only keep the material high specific surface area and large pore volume,but also improve the selective adsorption of CO2 by the material.Unsaturated sites（as Lewis acids）and amide groups（as Lewis bases）in the material can act synergistically to catalyze the Deacetalization-Knoevenagel condensation reaction and carry out multiple catalysis.This dissertation not only has some reference meanings for the synthesis of porous coordination polymers with high specific surface area,but also provides some ideas for the adsorption,separation and catalysis of mixed gas in porous coordination polymer materials.