Expanded graphite and preparation method thereof

Abstract

The invention relates to an expanded graphite material, and discloses expanded graphite and a preparation method thereof. The traditional high-temperature expansion method is combined with a graphite expansion furnace; the optimal expansion temperature is used; the product stability can be effectively improved through controlling the raw materials and the process parameters at the expansion temperature, so that the large-scale preparation of stable expanded graphite with controllable expansion times is realized; the expansion times is 200 to 300; the bore diameter is 30 to 100nm; the carbon content is stable. The temperature region is formed by defining the temperature of a feeding opening and a discharging opening; the expansion time is controlled by setting the feeding speed and the wind speed; then, the separation and collection are realized through wind speed; the large-scale preparation is realized; the inert gas protection is not needed; the graphite high-temperature oxidation caused by too high expansion temperature can be prevented, so that the expansion volume of the graphite is reduced.

Description

technical field [0001] The present invention relates to expanded graphite materials, more specifically, to an expanded graphite and a preparation method thereof. Background technique [0002] Expanded graphite is a new type of composite material on the atomic and molecular scales formed by inserting foreign substances between graphite layers, and has become a new development direction in the graphite industry. It not only retains the excellent physical and chemical properties of graphite, but also produces a series of new physical and chemical properties due to the interaction between the carbon atom plane and the intercalated substance, such as high electrical conductivity, superconductivity, catalytic properties, hydrogen storage properties, etc. The expanded graphite obtained by high-temperature expansion looks like a worm, has stable thermodynamic properties, has a very large specific surface area and rich pore structure, and can be used as an adsorption material for org...

AI Technical Summary

Problems solved by technology

The above scheme has the following problems: 1. Since the expansion process is affected by many aspects such as raw materials, feed speed, expansion temperature, time, wind speed, etc., the expansion multiple of the prepared expanded graphite cannot be controlled, and the expansion multiple of large-scale preparation cannot be stabilized. expanded graphite

2. Because the expansion temperature is too high, graphite will be oxidized at high temperature, thereby reducing the expansion volume of graphite. Therefore, on the one hand, it is necessary to control the reaction time and temperature, and at the same time, it is necessary to pass inert gas protection, resulting in complicated process and high cost.

3. The temperature in the furnace body is uneven, and the temperature of the inner wall of the furnace is obviously higher than that in the furnace, which leads to uneven heating of intercalated graphite during expansion and low reaction efficiency

4. After the reaction, due to the relatively small mesh number of expanded graphite, it is easy to get stuck in the equipment during transportation, which affects the product yield

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