CARBON
most common adsorption systems exploit the properties of carbon, materials of vegetable or mineral characterized by an extremely high porosity. They are activated by high temperatures in a controlled atmosphere and in the presence of gaseous substances likely to yield oxygen or dehydrating minerals and fireproof. The large number of microscopic pores develop in depth decreasing as their section and provide a surface, but also development of 1700 square meters per gram of materiale.
I carboni attivi sono costituiti per la gran parte da atomi di carbonio e si presentano sempre di colore nero sia che si trovino in polvere,in granuli,o in forme sagomate.
Le loro capacità adsorbenti sono particolarmente indicate per l'abbattimento dei composti organici con un peso molecolare che varia da 50 a circa 200. In genere i composti che presentano un peso molecolare minore non vengono adsorbiti sufficientemente a causa delle piccole dimensioni; al contrario i composti organici che presentano alti pesi molecolari vengono adsorbiti così fortemente che risulta poi estremamente difficile rimuoverli durante la fase di rigenerazione.
L'ammontare di materiale che può essere adsorbito dal carbone attivo viene chiamato retentività or adsorption capacity and is expressed as a percentage or weight in kg of organic contaminants adsorbed to 100kg of coal used, usually in operational applications for every 100kg of charcoal can be adsorbed from 10 to 30 kg of contaminant.
NOTE
adsorption Adsorption is to fix the molecules on the surface of the pores by chemical bonds and / or physical, that a substance (adsorbate) is absorbed by another (absorbent) should be operate under conditions of chemical and physical environment to facilitate the adsorption. To divide the substance adsorbed dall'adsorbente (desorption) is acting in the opposite direction, ie take in conditions under which adsorption can not take place if not a little.
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