▎ 摘　　要

NOVELTY - A strong protonic acid of concentrated sulfuric acid or nitric acid is added into ice water. Synthetic graphite, natural crystalline flake graphite and crystalline flake graphite are mixed, and the mixture is slowly added to concentrated sulfuric acid or nitric acid. Potassium permanganate or potassium dichromate metal salt is slowly added to mixture and mixed. The obtained graphite oxide is added to crucible container. The crucible container with graphite oxide is provided to microwave vacuum sintering furnace and processed, to obtain flocculent agglomerated graphene products. USE - Preparation of graphene product. ADVANTAGE - The method enables preparation of graphene product, with high yield. DETAILED DESCRIPTION - A strong protonic acid of concentrated sulfuric acid or concentrated nitric acid is added into ice water at constant temperature. Synthetic graphite, natural crystalline flake graphite and crystalline flake graphite in ratio of 1-5:0.1-1 are mixed, and the mixture is slowly added to concentrated sulfuric acid or concentrated nitric acid. Potassium permanganate or potassium dichromate metal salt is slowly added to mixture and mixed for 4-24 hours under ice bath condition. The proportion of graphite/sodium nitrate solid mixture and acid solution is 1 g/10-100 ml. The addition of potassium permanganate or potassium dichromate metal salt is 3-5 times more than the graphite. The graphite is mixed after dipping in ice-bath at 30 plus minus 5 degrees C for 2-10 hours. The reaction mixture is washed with deionized water and hydrochloric acid, to form filtrate of graphite oxide and to remove metal ions and unreacted sulfate groups or nitrate groups, and acid groups. The yellowish-brown or black brown graphite oxide is dried at 50-70 degrees C for 2-10 hours, to obtain pure and dried graphite oxide. The graphite oxide as precursor is added to alumina or quartz crucible container which does not absorb microwaves. The crucible is covered with crucible cover or quartz sheet glass, and the container is sealed with adhesive tape and provided with gap or air holes communicated with outside environment. The crucible container with graphite oxide is provided to center of multimode cavity of microwave vacuum sintering furnace, and the graphite oxide is spread. The door of the microwave vacuum sintering furnace is closed, and vacuumized to 0.01-0.06 MPa. The microwaves of 2-10 kW are quickly provided to graphite oxide for 2-10 seconds. The supply of microwaves is stopped, and vacuum is released. The furnace door is opened, to obtain flocculent agglomerated graphene products.