adsorption

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adsorption

 [ad-sorp´shun]
the action of a substance in attracting and holding other materials or particles on its surface; see also absorption.
attachment (def. 2).

ad·sorp·tion

(ad-sōrp'shŭn), Do not confuse this word with absorption.
The property of a solid substance of attracting and holding to its surface a gas, liquid, or a substance in solution or in suspension, for example, condensation of a gas onto a surface. Compare: absorption.
[L. ad, to, + sorbeo, to suck up]

Adsorption

Chemistry An accumulation/concentration of molecules of a gas or liquid on a surface interfacing with the gas or liquid, resulting in a relatively high surface concentration.
Histology The accumulation of a substance on a surface affected by the affinities of acids to bases—and vice versa—based on electrical attraction; adsorption may explain differential affinity for dyes that occurs in histologic preparations of tissues being examined by light microscopy.
Immunology The removal of nonspecific agglutinins, by incubating the fluid of interest in a serum—e.g., of bovine origin—which lacks the antigens to be measured.
Virology The adhesion of a substance to an organic particle in a solution—e.g., adhesion of a virus to a cell.

ad·sorp·tion

(ad-sōrp'shŭn)
The property of a solid substance to attract and hold to its surface a gas, liquid, or a substance in solution or in suspension.
Compare: absorption
[L. ad, to, + sorbeo, to suck in]

adsorption

The process by which a substance, such as a gas or dissolved solid, is attracted to, and adheres to, a surface.

adsorption

the taking up of gas or liquid by a surface or interface. In physical adsorption, molecules are held by VAN DER WAAL'S FORCES of attraction; in chemical adsorption there is exchange or sharing of electrons. Compare ABSORPTION.

Adsorption

The binding of a chemical (e.g., drug or poison) to a solid material such as activated charcoal or clay.
Mentioned in: Charcoal, Activated

ad·sorp·tion

(ad-sōrp'shŭn) Do not confuse this word with absorption.
The property of a solid substance of attracting and holding to its surface a gas, liquid, or a substance in solution or in suspension.
[L. ad, to, + sorbeo, to suck in]
References in periodicals archive ?
Similar to the RL value from the Langmuir isotherm, the n value from the Freundlich isotherm is related to the adsorption intensity where n > 1 indicates good adsorption over different equilibrium concentrations [33, 34].
This model is more general than the Langmuir isotherm as its deviation is not based on ideal assumptions such as equipotential of sorption sites, absence of steric hindrances between sorbed and incoming particles, and surface homogeneity on microscopic level [45].
Isotherm parameters K AHK HK HAK Langmuir isotherm [q.sub.m] (mg x 10.87 45.45 38.46 43.48 [g.sup.-1]) [K.sub.L] (L x 0.7022 0.3107 0.2962 0.2949 [g.sup.-1]) [R.sub.L] 0.1246 0.2435 0.2524 0.2532 [DELTA]G (kJ x -24.7 -22.7 -22.5 -22.5 [mol.sup.-1]) [R.sup.2] 0.9749 0.9750 0.9595 0.9622 Freundlich isotherm [K.sub.F] (mg/g) x 1.851 8.367 3.823 6.005 [(L/mg).sup.-1/n] 1/n 0.5959 0.5982 0.5550 0.8171 [R.sup.2] 0.9367 0.9548 0.9499 0.9595 D-R isotherm [q.sub.DR] (mg x 7.81 18.05 16.85 17.61 [g.sup.-1]) [beta] x [10.sup.-3] -2.266 -1.723 -1.064 -1.817 ([mol.sup.2] x [kJ.sup.-2]) [E.sub.a] (kJ x 1.183 1.357 1.221 1.321 [mol.sup.-1]) [R.sup.2] 0.9353 0.8909 0.7178 0.7878
Also, we observed that [r.sub.2] values of Freundlich isotherm were found higher than Langmuir isotherm for both adsorbents, so, adsorption process is well fitted to Freundlich isotherm, confirming multilayer coverage of adsorbate having heterogenic adsorbent surface.
Figure 8 shows a plot of Langmuir isotherms for the adsorption of lead and cadmium ions.
The Freundlich isotherm constant ([K.sub.F] and n) and Langmuir isotherm constant ([Q.sub.e] and b) were evaluated from slope and intercept and tabulated in table 3.
Van Elteren J, Budic B (2005) A solid-liquid extraction approaches to elucidate the chemical availability of metals in soils and sediment assuming Langmuir isotherm behaviour.
The equilibrium adsorption of metal ions on the biosorbent could be best described with Langmuir isotherms; sorption isotherms were evaluated using the popular linearized Langmuir model, represented by the following equation (3).
The mathematical expression of the Langmuir isotherm is calculated via the dimensionless separation RL constant defined by Webber and Chakkravorti to find the suitability of adsorption [9].
Langmuir Isotherm. Langmuir adsorption isotherm assumes that the maximum adsorption corresponds to a saturated monolayer of solute molecules on the adsorbent surface, having no interaction with molecules adsorbed from lateral sides [27].
Figure 2 points out that if we only apply Langmuir isotherm to shale adsorption in low relative pressure section (before the inflection point where monolayer adsorption switches to multilayer adsorption), Langmuir isotherm can properly match experimental data, which indicates that Langmuir isotherm is suitable for monolayer adsorption in shale and then justifies the analytical result that monolayer adsorption takes place in the process of nitrogen adsorption at low temperature for shale.