SORPTION EQUILIBRIUM General Considerations

General Considerations For batch-experiments it is preassumed that the reversible sorption is in equilibrium and that irreversible adsorption corresponds to these equilibrium conditions. Therefore, the corresponding partition coefficients for total, reversible and irreversible sorption are... 

General considerations The reversible sorption is assumed to be in non-equilibrium the irreversible adsorption corresponds to this condition. 

Generally, sorption estimates are based on equilibrium conditions only however, incorporation of kinetic considerations into sorption estimation techniques is likely to be an important area of future work. For example, the assumption of equilibrium sorption in dynamic field systems may result in calculating too much pesticide in the sorbed state. 

Liquid or amorphous materials may (also) show absorption. Here, the absorbate can dissolve in the absorbent, or it can be seen as adsorbing onto the surface of a great number of fine pores in the absorbent. Anyway, the amount absorbed would be proportional to the mass of absorbent, other things being equal. In most dry foods, it is unclear whether the mechanism is adsorption or absorption in liquid foods, it is always the latter. It is rarely observed in a dry food that the equilibrium amount of water taken up depends on the specific surface area of the food. Generally, the term sorption is used, leaving the mechanism involved out of consideration. 

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