Exploring The Effects Of Functional Groups On Graphene Materials On The Adsorptional Process Of SO₂

SO2 pollution is a severe problem in China. Adsorption and catalyze is a clean and water-saving way to deal with the problem. Activated carbon has been used to desulfurization flue gas and regeneration to recycling sulfur and adsorbents. Surfaced chemistry play a vital role in this conversion process. According to previous research, there is distractions towards the effect of oxygenated groups. [15, 16].Graphene oxide(GO) sheets are newly emerging materials with plentiful oxygenated groups on their surface[3]. Their basal plane is covalently surrounded by epoxy and hydroxyl groups[5] while the edges are decorated with carboxyl groups[6]. Even after reduction for achieving graphene, these functional groups are inevitable and cannot be removed completely. In an ideal model, an epoxy oxygen will combine with two adjacent carbon atoms, while a hydroxyl group is connected with one single carbon atom of the graphene sheet. Their different binding configurations could have different effects on the original electronic structure of graphene, thus affecting the adsorption performance and catalytic activities. Notably, there are few investigations that have recognized and distinguished these oxygenated groups on catalytic reactions. Understanding their different influencing mechanisms is important both in academic investigation and industrial development. Herein, we have tried to resolve this problem and to develop new and effective catalysts.We fabricated 3 types of macroscopic RGO foams via the directional ice-template freezing technique. Reduction is more than removal of oxygen functional groups, but selectively retain certain type moieties on GO sheets. Various reduction agent, for example, hydrazine[10]Na OH [7-9] heat treatment[12-14]were used to tune the functional groups on GO.Surface chemistry is the main factor that determines adsorption capacity of porous materials. To explore the effect of common oxygen functional groups on SO2 adsorption, Hummers method was used to prepare graphene oxide(GO). Chemical reduction agent, such as hydrazine hydrate, Na OH was used to get RGO with tuned surface chemistry. GO and RGO aerosol obtained by freeze drying. SEM, XRD were used to characterize physical structure of the material, FTIR and XPS characterize chemical composition. Conclusions we got so far was: functional groups located in the middle of graphene oxide, namely hydroxyl and epoxy groups impede the adsorption process, carboxyl and carbonyl groups attach to the edge of graphene has a promoting effect in the process.Functional groups located in the middle of graphene oxide, namely hydroxyl and epoxy groups impede the adsorption process, while carboxyl and carbonyl groups attach to the edge of graphene has a promoting effect in the process.With KOH as activator to activation of lignite, KOH etching in the coal, get the internal graphene materials with holes.So get irregular edge of the porous carbon has more carbon, that is more active functional group sites.In this paper, the results can provide theory for the design of functional porous carbon materials, research train of thought can be reference to the complex catalytic reveal the mechanism of carbon materials.