Preparation and characterization of colloidal dispersions of graphene-like structures from different ranks of coals

摘要

This paper focuses on preparation of colloidal solution of graphene-like structures from different ranks of coals:brown coal,bituminous coal,low-volatile bituminous coal,anthracite.It was found that brown coal thermo-oxidative destruction leads to formation of small d =32 nm(V=17％) and large d =122 nm (V=11％) fractions of nanoparticles.The thermo-oxidative destruction of bituminous coal leads to formation of nanoparticles d=50 nm(V=5.2％) and d=164 nm(V=16％).Thermooxidative destruction of low-volatile bituminous coal and anthracite leads to formation of nanoparticles,predominantly,d=122-190 nm.Carbon nanostructures obtained from coal are negatively charged at pH =2-12.Colloidal solution of carbon nanostructures at dispersed phase concentration 0.01 mg/mL is stable for 1 month.Electron diffraction patterns and X-ray analysis of carbon nanostructures showed that nanostructure from brown coal is amorphous and nanostructure from anthracite is crystalline.Results of coal macromolecules modeling and graphene-like structures obtained from them are presented.