How does the carbon remove the contaminant?
Contaminant removal can be via physical adsorption -Physisorption or by chemical reaction- Chemisorption, or a combination of these mechanisms. Physisorption The contaminant enters the carbon granule through transport pores (meso and macropores); it diffuses into the carbon matrix until it enters the smaller pores (micropores) where the adsorptive forces begin to take effect. Once it reaches a higher-energy area, the adsorptive forces become greater than the diffusion forces and the contaminant becomes trapped in the micropore. In Physisorption no reaction occurs and the contaminant remains unchanged. It can be desorbed and recovered by increased temperature or reduced pressure which is the basis of all solvent recovery operations. Chemisorption The contaminant enters the carbon by diffusion as above however the adsorbent is specially prepared to promote chemical reactions in which the contaminant is consumed. Specialist carbons are available from LAJU Carbon in which additional chemic
