Development Of Activated Carbon Composite Radon Adsorption Material

Due to the gas characteristics of radon,it is easily emitted from the ground or building materials.In poorly ventilated buildings,it can reach higher concentrations and is the second major cause of lung cancer.Therefore,in order to reduce the harm caused by radon to human health,appropriate measures should be taken to reduce its concentration.Activated carbon(AC)is currently the main commercial material for adsorbing radon and reducing radon,but its adsorption capacity is not high due to the relatively low proportion of micropores with adsorption blocking effect.Therefore,this article intends to use various nanoparticles as precursors to diffuse into the mesopores and macropores of activated carbon to prepare activated carbon composites rich in micropores to achieve high-efficiency adsorption of radon.The main research contents include:(1)Development of activated carbon/attapulgite composite radon adsorption material.In order to improve the adsorption performance of activated carbon for radon,one-dimensional attapulgite(AT)nanoparticles are used to fill the macropores and mesopores of activated carbon.In the experiment,the AT solution was first diffused into the pore structure of activated carbon,and then a microporous activated carbon/attapulgite(AC/AT)composite radon adsorbent material was prepared by high-temperature calcination.The composite materials were characterized by SEM,EDS,FTIR,TG,BET and other technologies,and the effects of AT on the structure,thermal stability and radon adsorption performance of activated carbon were studied in detail,and the static adsorption coefficient of the composite materials on radon was determined.The results show that AT can easily diffuse into the macropores and mesopores of activated carbon,forming a new micropore-rich interpenetrating network,and significantly increase the specific surface area and the proportion of micropores of activated carbon.The prepared AC/AT composite exhibits excellent radon adsorption performance and regeneration performance.When the filling content of attapulgite is 3wt%,the adsorption coefficient of activated carbon for radon can be increased from 4.28 L/g to 5.35 L/g,and The radon adsorption coefficient of five cycles still maintains the initial value of 92.7%.(2)Activated carbon/three-dimensional graphene composite radon adsorption material is developed.The activated carbon is immersed in a prepared graphene oxide(GO)solution,and a layer of graphene oxide solution layer is formed on the surface of the activated carbon and its macropores by ultrasound.The surface-coated activated carbon/three-dimensional graphene(AC/3DG)composite material was prepared by hydrothermal reduction and freeze-drying.The structure of the composite material was characterized by SEM and BET,and the adsorption coefficient of the composite material for radon was measured.The results showed that the composite material has abundant mesopores.Among them,the proportion of the composite material’s micropore volume increases,and the micropore volume accounts for The total pore volume ratio is significantly increased,thereby increasing the total adsorption capacity.When the filling content of three-dimensional graphene(3DG)is2wt‰(AC/3DG2),the adsorption coefficient of activated carbon for radon is increased from 4.28 L/g to 6.02 L /g,compared with pure AC adsorption coefficient increased by about 40.65%.The radon adsorption coefficient of five cycles still maintains the initial value of 85.6%.The method of preparing efficient radon adsorption materials by filling the macropores and mesopores of activated carbon with nanoparticles provided in this paper provides new ideas and ways for the modification and improvement of various gas adsorption materials.