Activated carbon is one of the most utilized adsorbent materials for liquid and air filtration. Very efficient it is obtained from carbonization and activation of minerals or natural organic products like peat, wood or fruit shell which confer multiple deployment in chemistry, industry, medicine and agri-food engineering.

This material is endowed with a very elaborated porous structure which shows a huge internal surface of contact able to absorb a large variety of substance (between 1000 and 2000 sq.m/g).

A particle of activated carbon is composed of three kind of pore: micro-pore (diameter less than 2nm), meso-pore (between 2 and 50nm) and macro-pore (bigger than 50nm).

 

 

 

 

Adsorption : this is the phenomenon whereby a gas or liquid molecule is fixed on adsorbent’s solid surface with more or less intense various process. Adsorbent’s quality depends on its physical and chemical characteristics at first, and those, through treatments, ascribed by the industrialist.

Main adsorbent materials you can find on the market are:

• Activated carbon from wood or coconut shell which are the most used industrially.
• Aluminiums’ oxides
• Silica’s gels
• Zéolites

In details

Adsorption is an interaction between the adsorbating molecule and a solid’s surface. It is originated in the intermoleculare attractive forces (Van Der Walls force) which are responsible in cohesion of condensed, solid or liquid phases. Different characteristics define the adsorbent’s quality: mass absorption area, porous volume, apparent density, hardness, grain’s size…

The adsorption phase stops when the material is saturated and when the pollutant is not held any more.