▎ 摘　　要

NOVELTY - A graphene membrane film (40) comprises several plate-shaped laminated graphene flakes containing physical bond or chemical bond for connecting pair of layers. The graphene membrane film has a thickness of 1-10 mu m. The distance between the pair of plate-shaped laminated graphene flakes is 1-10 Angstrom . The weight ratio of carbon with respect to oxygen contained in the graphene membrane film is 3-99.9 (weight/weight)%. USE - Graphene membrane film is used in system (claimed) for purifying solvent e.g. ethylene carbonate, propylene carbonate, ethyl methyl carbonate, toluene, xylene, benzene, hexane, and dimethylformamide used for fine chemical industries. ADVANTAGE - The graphene membrane film has excellent surface property and lipophilic property, and provides solvent with high purity. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) manufacture of graphene membrane film, which involves forming a graphene oxide dispersion liquid (20) by dispersing graphene oxide in distilled water, confining the graphene oxide dispersion liquid between a pair of substrates, and hydrothermally-reacting (CC) the graphene oxide dispersion liquid between the pair of substrates by applying heat and pressure; and (2) solvent purification system, which consists of the graphene membrane film, a pressure generator, and an inlet and an outlet for solvent. DESCRIPTION OF DRAWING(S) - The drawing shows the schematic view explaining manufacture of graphene membrane film. Lower plate (10) Graphene oxide dispersion liquid (20) Upper plate (30) Graphene membrane film (40) Hydrothermal reaction process (CC)