▎ 摘　　要

NOVELTY - A graphene precursor manufacturing system comprises a carbonization unit for carbonizing a biomass to obtain a carbonized material (C2), a modification unit for reacting the carbonized material with a superheated steam (V2) under high temperature and negative pressure, and including a main component portion having an internal space (125), a rotary unit (103) for agitating the carbonized material, which is accommodated in the internal space, and a heating unit for heating the internal space. The main component portion comprises an input portion (124) for charging the carbonized material into the internal space, and is connected to the carbonization unit. At least one of the main component portion and the rotary unit comprises a steam introduction portion, such that the superheated steam can be introduced into the internal space. USE - System is used for manufacturing graphene precursor (all claimed) for forming high-speed transistor, sensor and transparent electrode. ADVANTAGE - The system enables easy and large-scale manufacture of graphene precursor. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) manufacture of graphene precursor, which involves carbonizing biomass to obtain carbonized material, and modifying by reacting the carbonized material with superheated steam under high temperature and negative pressure; and (2) graphene precursor, which uses biomass as a raw material, and comprises hexagonal crystal graphite and rhombohedral crystal graphite. In diffraction peak obtained by X-ray diffraction measurement, the ratio (%) of integrated intensity of diffraction peak of (101) plane of the rhombohedral crystal graphite with respect to total of integrated intensity of diffraction peak of (101) plane of the rhombohedral crystal graphite and integrated intensity of diffraction peak of (101) plane of the hexagonal crystal graphite is 31 or more. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of a modification furnace. Rotary unit (103) Input portion (124) Internal space (125) Carbonized material (C2) Oxygen-containing gas (OG) Superheated steam (V2)