Synthesis Of Graphene Oxide Composites Based On Organic Molecules And Its Adsorption Properties

Water is the most abundant substance in the world,and the most important component of living things.It is also necessities of organisms.Additionally,water has played an important role in the development of human society,and the production of industry and agriculture cannot leave it.But water resources are limited and non-renewable resource in narrow sense.Therefore,an efficient and low-cost water pollution treatment method has become a major research topic.The GO composite based on natural organic molecules combines the advantages of graphene oxide with natural organic materials.Therefore,the thermal,mechanical and chemical properties of the composites have been greatly improved and the composites have broad prospects in the field of water treatment.In this subject,we prepared two natural organic molecules/GO composites,analyzed their characterization,and finally studied their adsorption performance of pollutants in water.The specific research results are divided into the following parts:1)GO was prepared by modified Hummers method,and magnetic graphene oxide was prepared by chemical co-precipitation.SEM,FT-IR,Raman,XPS,XRD and TG were used to characterize.After oxidation,many oxydic groups were inserted between the graphite layers,and the lattice structure was disordered.The carboxyl groups and the hydroxyl group on the carbon base plane makes them more active,showing a strong affinity to a variety of substances and easy to be modified by further covalent or non-covalent modifications.2)Preparation,characterization and adsorption properties of sodium alginate/carboxymethyl cellulose sodium/graphene oxide composite.The results showed that the molecular chains of sodium alginate/carboxymethylcellulose sodium penetrated into the magnetic graphene oxide layers,thus augmenting space between the layers and increasing specific surface area.Meanwhile,the infiltration of calcium ions strengthens the interaction between molecular chains,and therefore forms a three-dimensional structure and further increases the layer spacing.The cross-linking of three molecules significantly improves the mechanical properties and thermal stability of the composites.pH=7 and 100 mg/L initial concentration are the best conditions for adsorption.The Langmuir model and the quasi-second-order kinetic model can better fit the adsorption curve,indicating that the adsorption process to methylene blue belongs to monolayer adsorption and the theoretical maximum adsorption capacity is 90.25mg/g.3)preparation,characterization and adsorption properties of chitosan/polyvinyl alcohol/graphene oxide composite.Irregular particles can be observed obviously on the sheet structure.Thus,the dispersibility of adsorbent was increased,and the specific surface area and adsorption capacity of the material structure were improved.pH=9 and 2 g/L initial concentration are the best conditions for adsorption.The Langmuir model and the quasi-first-order kinetic model can better fit the adsorption curve,indicating that the adsorption process of Cu²⁺belongs to monolayer adsorption and the theoretical maximum adsorption capacity is 1025.22 mg/g.