Discussion on activated carbon and its application in tubeless ventilation cabinet

The application and principle of activated carbon in adsorption of waste gas in laboratory cabinet What is activated carbon? Activated carbon is a kind of porous carbonaceous material It has a highly developed pore structure The porous structure of activated carbon provides a large number of surface areas for it, and it can fully contact with gas (impurities), thus giving the unique adsorption performance of activated carbon, making it very easy to achieve the purpose of absorbing and collecting impurities Just like magnetic force, all molecules have mutual attraction Because of this, a large number of molecules on the pore wall of activated carbon can produce strong attraction, so as to attract harmful impurities into the pore diameter However, not all activated carbon can absorb harmful gases Only when the pore structure of activated carbon is slightly larger than the diameter of harmful gas molecules, and the harmful gas molecules can enter completely (too large or too small) can the adsorption effect of activated carbon be achieved The adsorption performance of activated carbon is determined by the physical and chemical properties of activated carbon and adsorbate The influence of these factors on the adsorption of activated carbon is analyzed and studied from the shape change of Adsorption Isotherm: 1) when the pore size of activated carbon is the same, the adsorption capacity increases and the adsorption isotherm expands upward when the specific surface area increases; when the specific surface area is the same, the pore size becomes smaller, the adsorption force increases in the field of low concentration, and the shape of adsorption isotherm compresses to the side of low concentration 2) When the molecular weight of adsorbate increases, the adsorption isotherm compresses to the side of low concentration; when the polarity of adsorbate increases, the combination of adsorbate and solvent water increases, and the adsorption isotherm is pressed down and further expands to the side of high concentration The main factors affecting the adsorption of activated carbon 1) the properties of activated carbon the physical and chemical properties of activated carbon determine the adsorption effect, and the properties of activated carbon are related to the raw material processing methods and activation conditions used in the manufacture of activated carbon The activated carbon for water treatment should have three requirements: large adsorption capacity, fast adsorption speed and good mechanical strength In addition to other external conditions, the adsorption capacity of the activated carbon is mainly related to the specific surface area of the activated carbon The specific surface area is large, the number of micropores is large, and there are more adsorbates that can be adsorbed on the microporous wall In order to ensure a strong adsorption efficiency, it is necessary to select coconut shell as the raw material of activated carbon 2 In order to ensure the adsorption efficiency of the filter, the company has developed a set of strict internal inspection standards 3 The establishment of internal inspection standard is optimized after numerous experiments It is necessary to ensure that the downstream concentration of the filter is within the safe value range, and the filter has a Zui maximum adsorption capacity 4 According to different adsorbed chemicals, activated carbon can be loaded with some chemicals in the production process through technical means to enhance the adsorption capacity of some or some kind of chemicals 5 The activated carbon is only a part of the filtration module In order to ensure the adsorption effect, biens added different adsorption media according to different types of modules.