Expandable graphite’s excellent potential

Expandable graphite is a synthetic embedded compound that expands or peels off instantaneously when heated. Once heated, its volume increases by up to 400 times, the loose packing density decreases, and the specific surface area increases by about 10 times, which can be pressed into a highly adhesive flexible graphite plate.

The main application is as a flame retardant. Due to the high temperature, the graphite expands and an expanded layer is formed on the surface of the material. This slows the spread of fire and minimizes the toxic gases and fumes produced during combustion, reducing harmful effects.

Expands the potential of graphite

(1) Environmental protection ability of water sources: expandable graphite has hydrophobicity and lipophilicity, and can selectively remove non-aqueous solutions in water, such as removing oil slicks from the sea, rivers and lakes. Expandable graphite can form a certain winding space when absorbing oil, and can store oil substances that are much larger than its total pore capacity. After adsorbing a large amount of oil, it can be assembled into a block, floating on the liquid level, easy to collect, and can be recycled and recycled. Since expandable graphite is basically composed of pure carbon, non-toxic and chemically inert, it will not cause secondary pollution in water.

(2) Liquid adsorption: In addition, expandable graphite can also be used for industrial wastewater emulsion oil removal and removal of oil-soluble substances, such as pesticides, etc., and has a good adsorption effect on many other organic or inorganic harmful components. In addition to selective adsorption in the liquid phase, expandable graphite also has a certain effect on the main components of air pollution caused by industrial exhaust gases and automobile exhaust, such as SOx and NOx.

(3) Wastewater treatment capacity: the expandable graphite is used to treat the printing and dyeing wastewater of woolen spinning mills, and under static conditions, the average removal rate of chemical oxygen demand (COD) in wastewater reaches 40%, and the average chromaticity is reduced by 40%. After using expandable graphite, the average removal rate of COD in wastewater reached 20% and the chromaticity decreased by 20% on average. Field experiments have shown that expandable graphite has its unique application prospect in the treatment of wool spinning printing and dyeing wastewater.

(4) The battery anode material is converted into electrical energy by using the free energy change of the reaction between the layers of expandable graphite. Usually expandable graphite is used as the cathode, lithium as the anode, or expandable graphite composite silver oxide as the cathode, zinc as the anode. Expandable graphite from fluorinated graphite, graphic acid and metal halides such as AuCl3 and TiF4 has been applied to batteries.

(5) Fireproof sealing strip: Because expandable graphite has excellent expandability and high temperature resistance, expandable graphite becomes an excellent sealing material, mainly used in fire doors, fireproof glass windows and other occasions. This expansion seal acts as a barrier to flue gas flow at room temperature and fire. At the same time, the expandable graphite can also be bonded to the carrier, and the shear resistance provided by the charcoal formed by the adhesive at high temperatures can effectively prevent the sliding of the graphite. It is mainly used for fire doors, but it cannot effectively block the flow of cold flue gas at room temperature or low temperature, so it must be used with room temperature sealant.

Advantages of expandable graphite as a flame retardant

(1) Forming an expanded layer that can shield thermal radiation, with excellent thermal diffusion;

(2) Prevent or slow down the spread of fire and toxic gases;

(3) Easy to apply, cost saving, low input, high performance;

(4) Non-toxic, halogen-free flame retardant additives;

(5) The neutral surface can be compatible with any catalyst system

The expansion characteristics of expandable graphite are different from other expansion agents, and are high-quality natural flake graphite produced by Franli factory, which is instantaneously treated at high temperatures and becomes worm-like, especially as a flame retardant material has obvious advantages, and can be used to purify water sources and protect the environment in the future. Such performance requirements are also extremely high, our Franli factory can provide such high-quality expandable graphite raw materials, if you need expandable graphite can contact us.