Method for preparing high-quality middle phase asphalt by co-carbonization method

Abstract

The invention provides a method for preparing high-quality middle phase asphalt by a co-carbonization method, and belongs to the technical field of coal tar asphalt deep processing. According to the method, a small amount of middle phase asphalt is used as additives; refined coal asphalt is used as raw materials for preparing high-quality middle phase asphalt. Firstly, the refined coal asphalt anda small number of middle phase asphalt additives are jointly put into a crushing machine to be crushed; uniform mixing is performed; next, the mixture is put into a high-temperature high-pressure reaction kettle for direct hot polymerization so as to obtain the high-purity middle phase asphalt product. The small amount of middle phase asphalt is added, so that the formation of middle phase asphalt products in the kettle is obviously accelerated, so that the temperature required by the forming of the middle phase asphalt by the refined coal asphalt is reduced; the time is shortened. The middlephase content of the obtained product is as high as 98 percent or above; the optical structure is in a wide area flow line shape; the softening point is low; the spinning performance is good. The middle phase asphalt can be used for preparing the high-end carbon materials such as high-performance carbon fiber. The method has the advantages that the process is simple; the energy consumption is low; the product is pure.

Description

technical field [0001] The invention relates to a method for preparing mesophase pitch, in particular to a method for preparing high-quality coal-based mesophase pitch by using a small amount of mesophase pitch as an additive through a co-carbonization method, and belongs to the technical field of coal tar pitch deep processing. Background technique [0002] Refined coal tar pitch is the product obtained by purification of medium temperature coal tar pitch. It not only has a very low ash content but also maintains a high degree of aromaticity, and is easy to polycondensate to form mesophase pitch. Compared with traditional coal tar pitch and petroleum pitch, the intermediate phase prepared by refined coal tar pitch is purer. Compared with artificially synthesized pure pitch, the source of raw materials is wide and the cost is low. It is a kind of preparation of mesophase pitch and then preparation of high-end carbon materials. ideal raw material. [0003] Mesophase pitch is...

AI Technical Summary

Problems solved by technology

However, the catalytic hydrogenation process not only complicates the production process, but also greatly increases the production cost, and the catalyst is difficult to separate from it, resulting in high ash content, which reduces the mesophase content

Another example is the patent CN103923681A, which uses coal liquefaction refined asphalt as raw material, uses self-washing oil, coking heavy oil, anthracene oil and other coal tar deep-processed products as additives, and prepares mesophase pitch by co-carbonization. Although the viscosity of the system is reduced, the The fluidity of the system, but at the same time it also prolongs the polymerization reaction time and increases energy consumption. Moreover, the addition of various oils will also introduce some impurities, which will increase the ash content of the mesophase pitch and cause adverse effects on subsequent processing.

In the patent CN103923682A, coal liquefaction refined pitch is used as raw material, high molecular polymer is used as additive, and mesophase pitch is prepared by co-carbonization method. Although the fluidity of the system is improved and fibrous mesophase pitch is obtained, these additives The molecular structure is quite different from the polycyclic aromatic hydrocarbons in asphalt, the combination of additives and asphalt cannot be determined, and defects such as pores may appear after subsequent processing and carbonization, and most additives play a role in delaying the polycondensation process. There are few studies on additives in the polycondensation process of refined asphalt and other raw materials

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