Preparation And Properties Of Co₂ Adsorption Composite Materials Based On Polyacrylamide

Nowadays,a series of environmental problems caused by excessive CO2 emissions are becoming increasingly prominent.Large-scale CO2 capture is the main way to reduce carbon emissions.Research in the field of large-scale CO2 capture has been slow to break through.Among them,high capture cost is the main obstacle to the current large-scale implementation of carbon emission reduction.Whether it is pressure swing physical adsorption or temperature swing chemical adsorption,the material cost and working energy consumption remain high.The core problem is that the material’s absorption/desorption performance,mechanical strength,water resistance,and cycle stability cannot meet the actual needs.Among the many research directions of CO2 capture materials,the advantages of solid a mine adsorbents such as low energy consumption,high selectivity,low cost and fast absorption/desorption rate have become one of the hot topics.Aiming at the core problem of CO2 capture,solid a mine adsorbents with good absorption/desorption performance,high mechanical strength,good water resistance,high cycle stability and low material cost were developed by grasping the characteristics of solid a mine adsorbents.The main research contents are as follows:(1)Synthesized organic composite spherical porous material with polyacrylamide(PAM)as the skeleton and polyglycidyl methacrylate(PGMA)as the skeleton adhesion layer.The synthesis method of the material by adding polymerized monomers in both emulsion phases and initiating polymerization of the emulsions at the same time by reverse phase suspension polymerization.The stability of the emulsion,the macroscopic appearance of the material,the influencing factors of the micropore structure of the material and the physical and chemical properties of the material were studied during the preparation process.PAM-PGMA composite spherical porous material was prepared.The ball diameter is 0.5-0.9 mm,the pore diameter is 0.7-2.2μm,the bulk density is 0.21-0.25 g/cm3,the specific surface area is 213 m2/g,the single particle crushing strength is 40-50MPa,the static contact angle between the surface and water is 116.1°.(2)An amine functionalized solid amine adsorbent with PAM-PGMA as the carrier was prepared.The amine group functionalization process uses chemical grafting.The influencing factors of the amination process were discussed and the CO2 adsorption performance of the material was characterized.PAM-PGMA material loaded with 50 wt.%PEI exhibited an adsorption capacity of 2.32 mmol/g at 85℃.Reaching 90%of the highest adsorption capacity in 13 min,complete desorption in 12 min.After 10 cycles of pure CO2 adsorption/desorption,the adsorption capacity tended to be stable,with a loss of 5.76%compared to the first cycle.(3)PAM-ZIF organic-inorganic composite materials were prepared.ZIF-8 and PAM are compounded by physical impregnation.Due to the introduction of ZIF-8,the specific surface area of PAM increased from 57 cm2/g to 433/540 cm2/g of 0.2-PAM-ZIF/0.3-PAM-ZIF.The porous spherical structure of PAM provides mechanical strength support to ZIF-8 and effectively solves the problem of ZIF-8 stacking.ZIF-8 in the PAM-ZIF composite loaded with 30%ZIF-8 exhibited an adsorption capacity of 80%of the adsorption capacity of pure ZIF-8.Excessive loading of ZIF-8 will reduce the adsorption efficiency of ZIF-8 in PAM-ZIF.