Method for preparing graphene by using waste graphite electrodes

A technology for discarding graphite and graphene, applied in graphene, chemical instruments and methods, inorganic chemistry, etc., can solve the problems of failing to fully utilize the economic value of graphite electrodes, low economic added value of products, and complicated processing processes, and achieve good results. Economic value and social value, the effect of less filling and larger specific surface area

Active Publication Date: 2018-02-09
CENT SOUTH UNIV
View PDF5 Cites 20 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] At present, most electrolytic aluminum plants in the world use open-air storage or landfill treatment of waste graphite cathode carbon blocks. Researchers have also developed a series of treatment methods, including roasting, flotation and sulfuric acid decomposition, etc.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for preparing graphene by using waste graphite electrodes

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0051] First, at room temperature, LiF-Na 3 AlF 6 -KF as the raw material, molten salt electrolysis of aluminum produced waste cathode graphite electrode surface mechanically peeled off 0.5cm thick intercalated graphite block, and used ball mill equipment to crush into 20μm graphite powder; the graphite powder is placed in the liquid phase containing aluminum chloride In the purification stripping solution, hydrochloric acid is used to control the pH value to 1.0, the mass ratio of graphite powder to liquid phase purification stripping solution is 1:100, the weight ratio of aluminum chloride to graphite powder is 1:2, and the temperature is 50°C Stir for 0.5h, stand still for separation after stratification, obtain a turbid solution containing graphene in the upper layer for use, and impurities in the lower layer containing coarse graphite particles as raw materials for the recovery of coarse graphite and sodium, aluminum, and fluorine;

[0052] Centrifuge the graphene-containing ...

Embodiment 2

[0058] First, at room temperature, the upper surface of the waste cathode graphite electrode produced by the molten salt electrolysis of lithium with LiCl-KCl as the raw material is mechanically peeled off 10cm thick intercalated graphite blocks and crushed into 60μm graphite powder by ball milling equipment; Placed in a liquid phase purification stripping solution containing aluminum nitrate, using nitric acid to control the pH to 1.5, the mass ratio of graphite powder to liquid phase purification stripping solution is 1:10, and the weight ratio of aluminum nitrate to graphite powder is 1: 3.5. Stir and process for 1 hour at a temperature of 90℃, stand still for layering, and separate to obtain a turbid liquid containing graphene in the upper layer for use, and impurities such as coarse graphite particles in the lower layer as coarse graphite and recovery of sodium, aluminum, and fluorine. Raw materials;

[0059] Centrifuge the graphene-containing turbid liquid by centrifugation...

Embodiment 3

[0064] First of all, at room temperature, the NdF 3 -LiF-Nd 2 O 3 The graphite electrode surface of the waste cathode produced by the molten salt electrolysis as the raw material is mechanically peeled off a 1cm thick intercalated graphite block, and is pulverized into 30μm graphite powder with a ball mill; the graphite powder is placed in a liquid phase purification layer containing aluminum chloride In the liquid, hydrochloric acid is used to control the pH value to 1.0, the mass ratio of graphite powder to liquid phase purification stripping liquid is 1:80, the weight ratio of aluminum chloride to graphite powder is 1:3, and the temperature is 60℃. 40min, stand still for layering, and separate to obtain a turbid liquid containing graphene in the upper layer and coarse graphite particles in the lower layer as raw materials for the recovery of coarse graphite and sodium, aluminum, and fluorine;

[0065] Centrifuge the graphene-containing turbid liquid by centrifugation at a low s...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
Specific surface areaaaaaaaaaaa
Specific surface areaaaaaaaaaaa
Specific surface areaaaaaaaaaaa
Login to view more

Abstract

The invention discloses a method for preparing graphene by using waste graphite electrodes. According to the method, the waste graphite electrodes in a process of fusing electrolytic metal by additionof ionic bond metal salt are used as raw materials, graphite which is intercalated by metal is stripped from the surface layers of the waste graphite electrodes, the part of graphite is intercalatedat high temperature in a fused salt electrolysis process, then liquid-phase stripping strengthening and elaborate-stage centrifugal classification are carried out, and finally, the graphene is finallyprepared by separation, purification and drying. The prepared graphene has few layers, and is large in specific surface area and low in energy consumption, waste materials are changed into things ofvalue, and the economic value and the social value are high.

Description

Technical field [0001] The invention belongs to the field of molten electrolytic graphite electrodes, and relates to a method for preparing graphene by using waste graphite electrode materials. Background technique [0002] The graphite electrode is mainly composed of anthracite coal and a binder. During the electrolysis process, the reaction caused by the molten salt electrolysis process such as high temperature heating, metal ion intercalation, electrochemical intercalation, metal ion and electrolyte penetration, etc. Cause the modification, expansion, and even damage of the graphite electrode. Take the molten salt electrolytic aluminum process as an example. For every ton of aluminum produced, 20kg-30kg of waste graphite cathode will be produced. [0003] At present, most electrolytic aluminum plants in the world use open-air storage or landfill treatment for waste graphite cathode carbon blocks. Researchers have also developed a series of treatment methods, including roasting,...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): C01B32/19C01B32/194
Inventor 纪效波孙伟侯红帅唐鸿鹄李思杰江锋赵文青
Owner CENT SOUTH UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products