山东益大新材料股份有限公司

精益求精、追求卓越

集土工合成材料生产、销售、设计、施工、服务于一体的土工合成材料综合企业。
/
/
Research progress on the preparation and application of needle coke

Research progress on the preparation and application of needle coke

(Summary description)Needle coke is a silver-white solid carbon material with metallic luster, which has obvious needle-like texture structure when observed under a microscope.

Research progress on the preparation and application of needle coke

(Summary description)Needle coke is a silver-white solid carbon material with metallic luster, which has obvious needle-like texture structure when observed under a microscope.

Information

Needle coke is a silver-white solid carbon material with metallic luster, which has obvious needle-like texture structure when observed under a microscope. Because of its low thermal expansion coefficient, high electrical conductivity, and high chemical stability, it is widely used in high-performance graphite electrode materials, lithium ion batteries, electrochemical capacitors and other fields. At present, only the United States, Japan and other countries can produce high-quality needle coke on a large scale. In recent years, my country's needle coke preparation technology has made major breakthroughs, and industrial production has basically been realized, but the quality is still far behind foreign high-quality needle coke.

1. Preparation of needle coke

Needle coke preparation is divided into three stages: raw material pretreatment, delayed coking, and calcination. The main task of raw material pretreatment is to remove the quinoline insolubles in the raw materials that are not conducive to the development of the mesophase to obtain refined raw materials; delay the process of coking that is to carbonize the refined raw materials to generate the mesophase. The quality of needle coke is directly affected by the formation process of the mesophase and its structural morphology. Therefore, by controlling the delayed coking conditions, obtaining a wide-area streamlined mesophase with stable performance is the key to preparing high-quality needle coke; calcination is a process in which the mesophase produced by delayed coking is subjected to high temperature treatment at about 1450 ℃. High temperature treatment can remove the volatile matter and moisture, and at the same time increase the degree of graphitization and then increase the density, conductivity and chemical stability. The needle coke obtained through this process can be used as the raw material for high-power graphite electrodes. To

2. Application of needle coke

In industry, the main application areas of needle coke are graphite electrodes for electric furnace steelmaking and anode materials for lithium-ion batteries, both of which account for more than 90% of market demand; it is widely used in electrochemical capacitors, graphene preparation and other fields in laboratory research. To

2.1 High-power and ultra-high-power graphite electrodes

Electric furnace steelmaking has become an important development direction of steelmaking enterprises in recent years due to its advantages of low energy consumption and low pollution emissions. Electric furnace steelmaking uses scrap steel as the main raw material, uses three-phase alternating current as the power source, and uses the high temperature of the arc generated between the graphite electrode and the metal material to heat, melt, and refine the metal. High-power and ultra-high-power graphite electrodes are necessary consumables for electric furnace steelmaking. Graphite electrodes prepared from needle coke have the advantages of high electrical conductivity, small thermal expansion coefficient, and high mechanical strength, which can meet the quality of large-capacity electric arc furnaces. Require. High-power and ultra-high-power graphite electrodes have also become the main application direction of needle coke. With the increase in research and development, the quality of needle coke in my country has steadily improved. With the strengthening of social environmental protection awareness and the development of power supply, the output and proportion of electric furnace steelmaking will steadily increase, and the demand for needle coke will also gradually increase.

2.2 Lithium battery anode material

Since the birth of lithium-ion batteries, they have quickly occupied the power supply market for electronic devices due to their high energy density, low cost, and long life. Needle coke has become a high-quality material for the negative electrode of lithium batteries because of its high conductivity, easy graphitization, and low price. By comparing the properties of pitch coke and needle coke after graphitization, it is found that needle coke is easier to graphitize than pitch coke under the same graphitization conditions, and the charge and discharge performance is also better than pitch coke. In recent years, the rapid development of new energy vehicles has driven the demand for lithium-ion batteries to rise rapidly. According to data from Zhiyan Consulting and Founder Securities Research Institute, since the outbreak of the new energy automobile industry, the demand for lithium battery anode materials has accounted for 30%-40% of the total demand for needle coke, and has gradually become one of the main application areas of needle coke.

3. Outlook

The preparation process of needle coke has made great breakthroughs with the efforts of researchers, but there are still many problems in large-scale domestic production of high-quality needle coke: raw materials such as coal tar pitch often require raw material pretreatment, and the pretreatment process is very complicated. , The cost is high, which is not conducive to industrial production. Therefore, looking for raw materials that do not require or only require simple pretreatment will be of great help to the next expansion of needle coke production. At the same time, exploring low-cost, simple process raw material pretreatment methods is also an effective solution to this problem. The current delayed coking reaction mechanism is not perfect, which makes it difficult to innovate in the selection and preparation of high-quality needle coke raw materials. The exploration of the mechanism will help to expand the choice of raw materials and effectively control the parameters of the delayed coking process. Therefore, the reaction mechanism needs to be further explored. The high temperature of the calcination process, excessive energy consumption, and high requirements for equipment and materials directly lead to an increase in the preparation cost. Finding new inhibitors or catalysts, reducing energy consumption and calcination equipment requirements are important directions that researchers need to explore.

Although needle coke has been used in industry, its application fields are few and the demand is unstable, which restricts the expansion of needle coke production scale. Therefore, other application areas of needle coke still need to be developed by researchers and practitioners. In the future, with the continuous deepening of research and the deepening of the understanding of reaction mechanism and raw materials, the large-scale production of high-quality needle coke is just around the corner.

Excerpt from "Carbon Technology", Volume 39, Issue 5, 2020

Scan the QR code to read on your phone

全国服务热线:

183-5379-9166

 

Marketing director:+86 183-5379-9166
Human Resources Management:+86 157-5370-6899
Mail:marketing@needlecoke.com
Web:www.sdydxcl.cn

Liangbao Temple Base: North of Hongqi Road, Liangbaosi Town, Jiaxiang County, Shandong Province

Park base: No. 1, Yida Road, Chemical Industry Park, Jiaxiang County, Shandong Province

Copyright © 2022 Shandong Yida New Materials Co., Ltd.   鲁ICP备2021039281号