Use adsorption to remove impurities such as water, carbon dioxide, and acetylene from the air. The porous solid used for adsorption is called an adsorbent. The main requirements for adsorbents are:
1) The adsorbent must be a porous material. Because the adsorbent is only carried out on the solid surface, the more pores and the larger the surface area, the stronger the adsorption capacity.
2) The adsorbent must be selective adsorption. That is, only the components that need to be removed are adsorbed, but not all components in the mixture.
3) The adsorption capacity should be large, that is, the mass of material that can be adsorbed per kilogram of adsorbent should be large. The adsorption capacity is small, and the amount of adsorbent required is large.
4) Must have a certain strength, pressure resistance, wear resistance, not easy to break.
5) Easy desorption and regeneration.
6) The price is cheap.
Adsorbents that can meet the above conditions are commonly used silica gel, activated alumina, aluminum glue, and molecular sieve.
