Study On The Characteristics Of Adsorption And Competitive Adsorption Of Biogas On Modified Graphene

As China’s energy demand is increasing,people are turning more attention to the development of new renewable energy.Landfills produce a lot of biogas,which is rich in methane gas and can be used as an energy source.Biogas recovery technology has been developed in many countries,and the adsorption separation method is a good choice.Adsorption separation is the use of an adsorbent to separate excess gas from CH4 gas,so the choice of adsorbent is critical.In this paper,the first principle principle was used to study the adsorption characteristics of the main gas components of biogas,CH4,CO2,H2 S and H2 O molecules,on different configurations of metal-doped graphene.In this paper,three metals were selected,namely Ni,Pd and Pt metals.Each of the metal-doped graphenes was constructed in 11 configurations: SV,SVN,SVN2,SVN3,DV,DVN,DVN12,DVN13,DVN14,DVN3,and DVN4,for a total of 33 M/GN substrates.Based on the results of adsorption energy and adsorption configuration,the Pader charge,EDD diagram and density of states of the partial configuration were further calculated and analyzed.The results of the analysis are as follows: 1)The adsorption of the four gas molecules by the single-defect graphene substrate is better than that of the double-depletion adsorption,and the double-abstract configuration has a near-zero adsorption of gas.The adsorption of CH4 in the four gases is the weakest,and the difference from the other three gas molecules is obvious.2)The electron transfer was analyzed by the Bader charge and EDD diagram.The results show that CH4 and H2 O molecules exhibit electron loss during the adsorption process,and the corresponding M/GN shows electrons.The CO2 molecules and H2 S molecules exhibit electrons during the adsorption process,and their corresponding M/GN performances are lost.electronic.The results of density densification analysis of these structures show that the hybridization between gas molecules and metal atoms does not occur.Combined with the Bader charge and EDD map analysis,the effect between the two is mainly from the transfer of electrons.Based on the calculation results of adsorption,the SVN and SVN2 configurations of two configurations Ni/GN were selected as possible adsorbents for biogas adsorption separation method,and verified by molecular dynamics method.The results obtained demonstrate that these two configurations are feasible as adsorbents for biogas recovery adsorption separation.At the same time,the results of adsorption analysis between the two can be obtained.The difference in adsorption energy between CO2,H2 S and H2 O is not enough to directly affect the order of adsorption of gas molecules,and is not enough to displace an adsorbed gas by an unadsorbed molecule.molecule.