Activated Carbon cas 64365-11-3

The main indicators of activated carbon include physical properties such as particle size, strength, moisture content, water capacity, bulk density, granular density, true density, specific surface area, and ash content, as well as adsorption performance indicators such as benzene adsorption rate and tetrachloride carbon activity. Carbon activated at low temperature (400°C) is called L-carbon, while that activated at high temperature (900°C) is known as H-carbon. H-carbon must be cooled under an inert atmosphere; otherwise, it will revert to L-carbon. The adsorption performance of activated carbon depends on the chemical nature and concentration of the activating gas, activation temperature, degree of activation, composition and content of inorganic substances in the carbon, among other factors, with the primary determinants being the nature of the activating gas and the activation temperature. The carbon content, specific surface area, ash content, and pH value of the aqueous suspension of activated carbon all increase with rising activation temperature. Higher activation temperatures result in more complete volatilization of residual volatile substances, a more developed microporous structure, and greater specific surface area and adsorption activity. As volatile components are removed from the carbon, its ash content increases. The ash in activated carbon mainly consists of K₂O, Na₂O, CaO, MgO, Fe₂O₃, Al₂O₃, P₂O₅, SO₃, and Cl⁻. The composition and content of ash significantly affect the adsorption activity of carbon, and ash can generally be removed or reduced by soaking in hydrochloric acid or hydrofluoric acid followed by rinsing with water. The ash content of activated carbon is closely related to the raw materials used in its production. The hydrogen and oxygen contents in activated carbon decrease as the activation temperature increases. The ability of activated carbon to adsorb acids or bases is related to the pH of its aqueous suspension: activated carbon that lowers the pH of distilled water has strong alkaline adsorption capacity, whereas that which raises the pH exhibits strong acidic adsorption capacity. The mechanical strength of activated carbon depends on the raw material and carbonization temperature; when the carbonization temperature exceeds 700°C, mechanical strength increases significantly. In addition to widespread applications in wastewater purification and analytical chemistry, activated carbon is primarily used in chemical beneficiation processes for extracting gold and silver. Its applications span nearly every sector of the national economy. In gaseous adsorption, it is used to remove harmful gases from exhaust streams, purify air in environmental protection, recover solvents, desulfurize flue gas, protect against atomic radiation, and eliminate radioactive fission products, as well as radioactive iodine, krypton, and xenon released from nuclear facilities. In liquid-phase adsorption, it is employed in food processing for refining glucose, maltose, sugar, dairy products, edible oils, fruit juices, alcoholic beverages, and food additives such as monosodium glutamate, citric acid, agar, pectin, and other foodstuffs; in pharmaceuticals for purifying various drugs and injectables; in the chemical industry for refining, purifying, and recovering chemical reagents and industrial oils; in wastewater and drinking water treatment; in synthetic fiber and petroleum refining industries; and as catalysts or catalyst supports. With advances in science and technology, the variety and adsorption capacity of activated carbon will continue to expand and improve. For example, recently developed high-specific-surface-area activated carbons can achieve surface areas up to 3000 m²/g, further broadening their application scope. This information is provided by