Study On CO₂ Capture Performance Of Functionalized Cu Based Metal-organic Frameworks

As one of the global environmental problems,the "greenhouse effect" has attracted much attention.The primary responsible gas in the greenhouse effect is CO2,which is increasing the pressure on the global climate.CO2 capture and separation technology is the urgent need for greenhouse gas CO2 emission reduction.The metal organic framework(MOFs)material has a significant advantage in capturing CO2.In order to improve the adsorption performance of MOFs to CO2,the compound material of the L-arginine modified GO with MOFs(MOF/GO-Arg)was synthesized.The introduction of amino modified layer graphite into metal organic skeleton material not only adjusts MOFs aperture to improve its adsorption effect,but also improves its anti-humidity performance.The structure and chemical properties of the matrix and its composite materials were analyzed by XRD,FT-IR,N2 adsorption-desorption,thermal analysis and SEM.At the same time,their adsorption properties were compared under different temperature,flow rate and humidity.Then,four kinetic models were used to fit the adsorption curves of the three adsorbents under different conditions to find the optimal dynamic model.Finally,the performance of three adsorbents in the optimal temperature,flow rate and high humidity is investigated.The main contents and results of the paper are as follows:1.The composite materials of Cu-BTC,composite materials with graphite oxide(MOF/GO)and L-arginine modified GO(MOF/GO-Arg)were synthesized and their adsorption properties were compared.After a variety of means characterization,structural and chemical properties of MOF/GO-Arg are better than the other two kinds of materials.2.The experiment of CO2 dynamic adsorption was carried out in CO2-N2 mixture.The experimental results at the temperature of 25?,50 ? and 70 ?,showed that MOF/GO-Arg was the greatest adsorbent at 50 ?.Under the optimal temperature of each sample,CO2 adsorption performance respectively in mixture flow of 40 mL/min,60 mL/min and 80 mL/min was investigated.Adsorption capacity of the weight of three samples respectively lg in 40 mL/min is better than that on other flow.The MOF/GO-Arg had the best adsorption effect,reaching 3.371 mmol/g.In the end,the adsorption performance of Cu-BTC and MOF/GO were compared under different humidity at 50?,40mL/min and found that MOF/GO was better than Cu-BTC.3.Using four dynamics model to evaluate adsorption behavior of three kinds of MOFs materials under the different adsorption temperature,flow rate and humidity,which found Fractional kinetic model is the best model for describing their CO2 adsorption behavior.4.In addition to studying the adsorption effect of metal organic matrix composite materials,its cyclic adsorption performance is also an important index to evaluate its adsorption capability.The three samples were respectively carried out on 10 adsorption-desorption cycles under the optimal temperature,flow rate and humidity.Obviously,the results show that after repeated experiments the adsorption performance of the three samples was not decreased,which can be recycled.