- "Adsorption is the adhesion of atoms, ions or molecules from a gas, liquid or dissolved solid to a surface."
The relationship between the amount of gas adsorbed on a solid surface and the pressure of the gas above the surface at a constant temperature.
Surface area determination: The measurement of surface area is essential in understanding adsorption isotherms as it helps determine the number of available adsorption sites on a surface.
Adsorption isotherm models: The study of the various models of adsorption isotherms is important as it helps in the prediction and understanding of the adsorption behavior of a system.
Langmuir isotherm: This model is based on the assumption that the adsorption of a molecule occurs at specific sites on the surface, and once these sites are occupied, no further adsorption can occur.
BET isotherm: This model is based on the assumption that the surface contains a wide range of active sites with different affinities for the adsorbate, and the adsorption process on the surface is multi-layered.
Freundlich isotherm: This model describes non-specific adsorption of a solute onto a surface that has a wide range of adsorption energies.
Adsorption kinetics: The rate of adsorption is important in the understanding of the mechanism of adsorption and the influence of various parameters on the process.
Surface chemistry: Understanding the chemical structure of a surface, such as its composition, charge, and surface properties, including polarity, is essential in determining the adsorption behavior of a system.
Adsorption thermodynamics: The study of adsorption thermodynamics helps in understanding the energy and entropy changes that occur during the adsorption process.
Surface modification: Surface modification techniques such as functionalization of surfaces or changing their morphology can greatly affect the adsorption characteristics of a system.
Adsorbent characterization: The characterization of adsorbent materials is important in understanding their morphology, pore size distribution, and surface functional groups that influence their adsorption behavior.
Adsorption in solutions: The behavior of adsorbates in solutions is different compared to gases, and understanding the physicochemical properties of the solutions can help in determining the adsorption behavior.
Application of adsorption: The study and understanding of adsorption isotherms have numerous applications in various fields, such as environmental remediation, catalysis, separation processes, and drug delivery systems.
Langmuir Isotherm: It is a mathematical expression that describes how molecules adhere to a surface, typically a solid surface, forming a monolayer, and shows a saturation point where no more molecules can be adsorbed.
BET Isotherm: It is a mathematical model that describes physical adsorption of gas molecules on a solid surface and considers multilayer adsorption as well.
Freundlich Isotherm: It is an empirical formula that describes heterogeneous (non-uniform) surfaces and uneven distribution of active sites of adsorption.
Temkin Isotherm: It assumes that the heat of adsorption of all the molecules in the layer decreases linearly with coverage due to adsorbate-adsorbate interactions.
Sips Isotherm: A three-parameter equation that is used to describe the adsorption of a gas on a solid surface.
Radke-Prausnitz Isotherm: It is used to describe the adsorption of multiple adsorbate molecules on a solid surface in a competitive process.
- "This process differs from absorption, in which a fluid (the absorbate) is dissolved by or permeates a liquid or solid (the absorbent)."
- "The adsorbate does not penetrate through the surface and into the bulk of the adsorbent."
- "The term sorption encompasses both adsorption and absorption."
- "Desorption is the reverse of sorption."
- "Like surface tension, adsorption is a consequence of surface energy."
- "The adsorption process is generally classified as physisorption (characteristic of weak van der Waals forces) or chemisorption (characteristic of covalent bonding)."
- "It may also occur due to electrostatic attraction."
- "The nature of the adsorption can affect the structure of the adsorbed species."
- "Heterogeneous catalysts, activated charcoal, adsorption chillers, synthetic resins, increasing storage capacity of carbide-derived carbons, and water purification."
- "Adsorption is present in many natural, physical, biological, and chemical systems."
- "Adsorption, ion exchange, and chromatography are sorption processes in which certain adsorbates are selectively transferred from the fluid phase to the surface of insoluble, rigid particles."
- "Pharmaceutical industry applications use adsorption as a means to prolong neurological exposure to specific drugs or parts thereof."
- "The word 'adsorption' was coined in 1881 by German physicist Heinrich Kayser."
- "Although adsorption does often precede absorption."
- "Adsorption is the adhesion of atoms, ions, or molecules from a gas, liquid, or dissolved solid to a surface."
- "Like surface tension, adsorption is a consequence of surface energy."
- "In a bulk material, all the bonding requirements of the constituent atoms of the material are fulfilled by other atoms in the material."
- "Atoms on the surface of the adsorbent are not wholly surrounded by other adsorbent atoms and therefore can attract adsorbates."
- "For example, polymer physisorption from solution can result in squashed structures on a surface."