Method for preparing graphene by using cathode carbon block return scrap

Abstract

The invention provides a method for preparing graphene by using a cathode carbon block return scrap, and belongs to the technical field of solid waste treatment. After the cathode carbon block return scrap is subjected to acid and alkali leaching treatment, the content of carbon in the carbon powder can be increased, most of redundant impurities are removed, meanwhile, the particle size of the carbon powder is reduced, the quality of the carbon powder is improved, the carbon powder can be used for subsequent preparation of graphene, and then the utilization degree of the cathode carbon block return scrap is improved; the preparation method comprises the following steps: preparing carbon powder, oxidizing and expanding the carbon powder under the action of an oxidizing agent, inserting an intercalator into gaps of the carbon powder under the ultrasonic action, treating by utilizing a microwave-assisted stripping method, and stripping the carbon powder into layered graphene under the action of the intercalator, thereby realizing high-valued utilization of the cathode carbon block return scrap. The result of the embodiment shows that the size of the graphene prepared by the method provided by the invention is 5-15 microns.

Description

technical field [0001] The invention relates to the technical field of solid waste treatment, in particular to a method for preparing graphene by using cathode carbon block return materials. Background technique [0002] The cathode in the aluminum industry refers to the container containing molten aluminum and electrolyte, which consists of three parts: steel tank shell, cathode carbon block group and insulation material. Among them, the cathode carbon block is the most critical part. It plays the dual role of conducting electricity and forming the lining of the electrolytic cell. In addition to holding the aluminum liquid and electrolyte, it is mainly used to conduct current, that is, electrons are introduced into the electrolytic cell from it. . In the process of aluminum electrolysis, the environment in the electrolytic cell is very harsh: high temperature, strong magnetic field, and strong corrosive electrolyte. The cathode carbon block must not only bear the erosion o...

AI Technical Summary

Problems solved by technology

These cathode carbon blocks are difficult to realize reuse due to too many impurities. For example, the utilization of sawing scraps only accounts for 10%; the utilization of graphite chips (particle size≤4mm) produced after sawing only accounts for 60%; The utilization of the graphite powder (80% below 200 mesh) produced in the end only accounts for 30%

At the same time, even if the cathode carbon block return material can be reused, due to the small size of the residual material, asphalt needs to be added during the recycling process, which not only increases the preparation cost of the graphitized cathode, but also produces products with low strength indicators and internal , there will be cracks on the outside

Usually, this part of graphite residue is piled up in a large amount, which not only causes a serious waste of resources, but also causes safety hazards and environmental problems.

Images