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The term sorption encompasses both adsorption and absorption, and desorption is the reverse of sorption. IUPAC definition adsorption : An increase in the concentration of a dissolved substance at the interface of a condensed and a liquid phase due to the operation of surface forces.
Adsorption is the adhesion of ions or molecules onto the surface of another phase. [1] Adsorption may occur via physisorption and chemisorption. Ions and molecules can adsorb to many types of surfaces including polymer surfaces.
The Langmuir model of adsorption [2] assumes . The maximum coverage is one adsorbate molecule per substrate site. Independent and equivalent adsorption sites. This model is the simplest useful approximation that still retains the dependence of the adsorption rate on the coverage, and in the simplest case, precursor states are not considered.
Absorption is a physical or chemical phenomenon or a process in which atoms, molecules or ions enter the liquid or solid bulk phase of a material. This is a different process from adsorption , since molecules undergoing absorption are taken up by the volume, not by the surface (as in the case for adsorption).
Selective adsorbent materials (e.g., zeolites, (aka molecular sieves), activated carbon, etc.) are used as trapping material, preferentially adsorbing the target gas species at high pressure. The process then swings to low pressure to desorb the adsorbed gas.
Chemisorption is a kind of adsorption which involves a chemical reaction between the surface and the adsorbate. New chemical bonds are generated at the adsorbent surface. Examples include macroscopic phenomena that can be very obvious, like corrosion [clarification needed], and subtler effects associated with heterogeneous catalysis, where the catalyst and reactants are in different pha
In the study of heat transfer, absorptance of the surface of a material is its effectiveness in absorbing radiant energy. It is the ratio of the absorbed to the incident radiant power . [ 1 ]
These tasks are loading the feed, running the gradient elution, recycling of weakly adsorbing site fractions, fractionation of the purified product, recycling of strongly adsorbing site fractions, cleaning the column from strongly adsorbing impurities, cleaning in place and re-equilibration of the column to start the next purification run. All ...