Activated carbon masks Overview
Is a black powder, granules or pellets having a porous amorphous carbon, the main component is carbon, also contain small amounts of oxygen, hydrogen, sulfur, nitrogen, chlorine. Also has a fine structure as graphite, but the smaller grains, irregular accumulation between layers. Having a large surface area (500 to 1,000 m 2 / g), there is a strong adsorption properties, can absorb a gas, liquid or colloidal solids on its surface; for liquid, gas adsorbing substance can be the quality of activated carbon is close to their quality. Its selective adsorption of non-polar material is more easily adsorbed than the polar substances. In the same system material, the higher the boiling point of the substance to be adsorbed more easily, the lower the temperature the greater the pressure the greater the concentration, the greater the amount of adsorption. On the contrary, under reduced pressure, the desorption temperature is conducive to the gas. Commonly used in gas adsorption, separation and purification, solvent recovery, sugar, oil, glycerol, drug bleaching agent, water and refrigerator deodorant, gas mask canisters agent, also used as a catalyst or a metal salt supported catalyst. The raw materials for the production of activated carbon wood, hard shell or animal bones, mainly coal, by dry distillation, after activation treatment to get carbon production methods are: ① water vapor, carbon dioxide, flue gas and other gas activation method. Using steam or carbon dioxide at 800 ~ 900 ℃ activated carbon. ② chemical activation method, such as phosphoric acid, zinc chloride method. Activator activation using pore porosity developed the role of the preparation of activated carbon.
