Under certain operating conditions, the gas mixture by adsorption bed, adsorption by adsorption, adsorption after a period of time, when starting from the adsorbent in the laminar flow of the gas adsorbed mass (or its concentration reaches a specified value), think bed fire, adsorption properties of adsorbent adsorption quantity at this time is called dynamic activity of adsorbent.
The activity is not only related to the characteristics of adsorbents and adsorbents, but also related to temperature, concentration and operating conditions.
The kinetic activity value of adsorbent is the main basis for the design of adsorption system.
The adsorption rateThe adsorption process often takes a long time to reach equilibrium, and the contact time is limited in the actual production process.Therefore, the amount of adsorption depends on the adsorption rate, and the adsorption rate is related to the adsorption process, the adsorption process can be divided intoThe adsorption process often takes a long time to reach equilibrium, and the contact time is limited in the actual production process.Therefore, the amount of adsorption depends on the adsorption rate, and the adsorption rate is related to the adsorption process, which can be divided into the following steps:dxd activated carbon
(1) External diffusion, the adsorbate from the main air flow through the air film around the particles to the outer surface of the adsorbent; (2) Internal diffusion, the adsorbate from the outer surface through micropores to the surface of the adsorbent micropores
(3) adsorption, the adsorbent reached the microporous surface of the adsorbent is adsorbed
(4) The desorbed adsorbate diffuses to the main body of the gas phase through internal and external diffusionPhysical adsorption process is generally controlled by internal and external diffusion, chemical adsorption is controlled by both surface dynamics and internal and external diffusion.Because of the complexity of the adsorption process and many influencing factors, it is difficult to derive the rate theoretically, so it is generally determined by experience or model experiment.Activated carbon was prepared by using Liaohua petroleum coke as raw material and KOH as activator. The effects of alkali-coke mixing mode, particle size of raw material, carrier gas flow rate, different chlorophyll immersion, drying and heating rate on the properties of activated carbon were investigated.The experimental results show that Liaohua petroleum coke is a high quality raw material for the preparation of activated carbon with high specific surface area. The mixing mode of alkali coke, the particle size of raw material and the velocity of activated gas all affect the performance of the product.The specific surface area of activated carbon was obtained in the following order: water ~ glacial acetic acid >, ethanol >, methanol ~ tetrahydroaromatic >, ethylene glycol >, 30% hydrogen peroxide, which indicated that the removal of potassium compounds in activated carbon particles had a great influence on the formation of activated carbon pores and the adsorption performance.The microcrystalline structure and surface properties of the raw materials were changed by pre-carbonization, and the effect of these changes on the properties of the activated products was emphatically investigated.activated carbon supplier