Sorb

Sorb is a general term used in chemistry and environmental science to describe the uptake of one substance by another material. The verb form, to sorb, covers adsorption, absorption, or both. The substance being taken up is called the sorbate, and the material that sorbs it is the sorbent. Sorption is the opposite of desorption and can occur under diverse conditions and phases (solid–gas, solid–liquid, or liquid–liquid).

Sorption processes can be physical (physisorption) or chemical (chemisorption). They are often analyzed with sorption isotherms, such as Langmuir or Freundlich models, and with kinetic models like pseudo-first-order or pseudo-second-order equations. The quantity sorbed at a given temperature and pressure is referred to as the sorption capacity.

Common sorbent materials include activated carbon, silica gels, zeolites, clays, ion-exchange resins, and various polymers. These materials are used to remove contaminants, separate components, or stabilize substances in a range of applications.

Applications of sorption are widespread. In environmental engineering, sorption is used for water and air purification and for soil and sediment remediation. In industry, it supports gas purification,Catalysis, and controlled-release formulations in pharmaceuticals. In packaging and materials science, sorption helps control moisture and chemical stability.

Key distinctions include adsorption, which is typically surface-bound, and absorption, which involves uptake into the interior of the sorbent. The reversibility of sorption varies with system conditions, leading to desorption or, in some cases, irreversible binding.