Study On Adsorption Properties Of Carbon Dioxide With Porous Silicon Aluminum Based Materials By Pressure Swing Adsorption

About forty per cent of man-made CO₂ comes from coal-fired power plants,which has the characteristics of large emission and low CO₂ concentration.It is urgent to find effective ways to reduce CO₂ emissions from power plants and mitigate the greenhouse effect.The energy consumption of variable pressure adsorption is low,the separation of low concentration gas is good,and the environment is friendly.In this paper,a simple preparation process,excellent adsorption agent ang stable adsorption performance for the adsorption of CO2 in the gas of adsorption power plant was studiedThree carrieres including ordered mesoporous alumina?OMA?,organic aluminum?MIL-53?Al??,NaY molecular sieve?NaY?were modified,by ethanol amine?MEA?as amino-modifying agent to prepare three kinds of adsorbent that were refered as OMA-MEA,MIL-53?Al?-MEA,NaY-MEA.The morphology structure and properties of adsorbent were characterized before and after modification by N₂ isothermal adsorption desorption?BET,BJH?,X-ray diffraction?XRD?,transmission electron microscopy?TEM?and infrared spectroscopy?IR?.The influence of impregnation time,adsorption bed pressure,airspeed and modifier impregnation concentration on adsorption properties of adsorbent were discussed by means of the simulated flue gas adsorption device.The regeneration properties and stability of adsorbent were studied from the time of regeneration and times of regeneration.The ordered mesoporous alumina was synthesize by precipitation method.It has a higher specific surface area,the pore diameter is uniform.After modification,the structural characteristics of OMA were basically maintained.The optimum adsorption conditions of OMA-MEA were shown as follows:The immersion time of MEA is 2h at298K,the adsorption pressure is 0.4mpa,the airspeed is 300h^-1,the MEA load concentration is 60%,and the saturation adsorption capacity of CO₂ reaches 165.5mg/g.The adsorption effect of the adsorbed saturation of OMA-MEA was still stable after8 times regeneration,and the saturation adsorption capacity of regenerated adsorbent still reached 157.7 mg/g,and the regeneration effect of adsorbent was good.The organic aluminum is prepared by hydrothermal synthesis method.It has a super high specific surface area.The pore diameter distribution is mainly microporous and there are partial mesoporous.After modification,the structural characteristics of the modified mil-53?Al?were basically maintained.The optimum adsorption conditions of the MIL-53?Al?-MEA were shown as follows:The immersion time of MEA is 3h at 298K,,the adsorption pressure is 0.3 MPa,the airspeed is 200h-1,the MEA load concentration is60%,and the CO₂ saturation adsorption capacity reaches 178.9 mg/g.The adsorption effect of the adsorbed saturated MIL-53?Al?-MEA was still stable after 8 times regeneration,and the saturation adsorption capacity of regenerated adsorbent still reached 168.7 mg/g,and the regeneration effect of adsorbent was good.The water thermal synthesis method is used to prepare NaY molecular sieves,It has high specific surface area,narrow pore diameter and neat channel.After modification,the structure characteristics of the modified NaY were basically maintained.The optimum adsorption conditions of na-mea were shown as follows:The dip time of MEA is 3h at298K,is 3h,the adsorption pressure is 0.3 MPa,the airspeed is 300h-1,the MEA load concentration is 40%,and the saturation adsorption capacity of CO2 reaches 168.6mg/g.The adsorption effect of the adsorbed saturated na-mea was determined,and the adsorption effect of the adsorbent was stable after 8 times regenerated,and the saturation adsorption capacity of regenerated adsorbent still reached 159mg/g,and the regeneration effect of adsorbent was good.The adsorption effect of prepared adsorbent is more efficient and stable with good regenerated property is of good value of industrialization and has been preliminarily required to realize industrialization.