What is Adsorption?
Adsorption is a process that uses special solids (called adsorbents) to remove substances from either gaseous or liquid mixtures. The term “adsorption” was first coined in the late 19th century, but the process itself was not widely used until the 1940s and 50s when activated carbon was first used for municipal water treatment. These days, it is not always adsorption that matters, but desorption. This is because the simple uptake of a component generally only changes its phase (i.e., from either gas- or liquid-phase to adsorbed- or solid-phase). In order to be economical and to protect the environment, it is usually important to desorb the component in a fluid that is richer than that from which it was originally adsorbed. This accomplishes enrichment or purification in a cyclic manner. There are a variety of standard methods to force an adsorbent to take-up then release certain components. One, that applies only to gas-phase separations, is cycling the pressure – resulting in what is
The phenomenon that solid absorbs gas is called adsorption. Microcosmically, when gas molecule moves to the surface of solid (adsorbent), because of the mutual reaction between gas molecule and molecule in the surface of solid, gas molecule will stay on the surface intermittently, which makes the concentration of the solid surface increase. Generally, the stay will last for a little time and the change of concentration is also little. But for there exists strong action between some special gas molecule and solid, not only the time for stay is long (even eternally), but also the concentration is high. Such phenomenon is the adsorption that gas molecule makes on the surface of solid. Adsorption can be classified into two types. One is physical adsorption that means the inter-force between molecule of adsorbent material and adsorbent molecule is Vander Val gravitation; the other is chemical adsorption that means chemical affinity forms between molecule of adsorbent material and adsorbent
Adsorption is a process, similar to absorption, by which a substance in a gas or liquid becomes attached to a solid. The substance can be a pollutant, called an adsorbate, which is attracted to the surface of a special solid. Adsorption occurs naturally, but industrialists have perfected adsorption methods to clean up hazardous waste or purify drinking water. Tiny chemical particles suspended in another phase of matter, meaning in the air as a gas or in water as a liquid, are sometimes considered contaminants. These tiny particles can be separated from that phase, called the adsorbent, to enter a different phase. A material of another phase, like the solid carbon, preferentially targets these particles and bonds the adsorbate to its surface. The remaining air or liquid has been purified. This differs from absorption where the particles never change phase, but enter pores of the solid along with the accompanying air or water. Natural or organic methods of adsorption take place all the t
