Compară metode

	Izoterma de Adsorbție (Langmuir-Freundlich)	Modelul PFR (Reactor cu Flux Pistonic)
Domeniu	Fizică aplicată	Fizică aplicată
Familie	Process / pipeline	Process / pipeline
Anul apariției	1918	1962
Autorul original	Irving Langmuir	Octave Levenspiel
Tip	Empirical and theoretical adsorption equilibrium model	Mathematical model for plug-flow reactor
Sursa seminală	Langmuir, I. (1918). The adsorption of gases on plane surfaces of glass, mica, and platinum. Journal of the American Chemical Society, 40(9), 1361-1403.	Levenspiel, O. (1999). Chemical Reaction Engineering (3rd ed.). John Wiley & Sons. ISBN: 978-0-471-25424-9
Denumiri alternative	Langmuir isotherm, Freundlich isotherm, sorption equilibrium	ideal tubular reactor, plug-flow model, PFR
Înrudite	3	3
Rezumat	Adsorption isotherms describe the equilibrium uptake of a substance on a solid surface as a function of gas or solution phase concentration at constant temperature. The Langmuir isotherm (1918) and Freundlich isotherm (1906) are classical empirical models. The Langmuir model assumes monolayer coverage and is mechanistic; the Freundlich model is empirical and describes multilayer or heterogeneous adsorption. These isotherms are essential for designing separation processes (activated carbon filters, molecular sieves) and understanding pollutant sorption.	The PFR (Plug Flow Reactor) model describes the behavior of a tubular reactor in which fluid elements move through as distinct plugs with no axial mixing. Fluid at the inlet is freshly unreacted; as it travels downstream, reactions progress. This idealized model, formalized by Octave Levenspiel alongside CSTR theory, is the opposite extreme: while CSTRs are fully mixed, PFRs have no axial mixing. In practice, PFRs achieve higher conversion than CSTRs for the same residence time and are widely used in the chemical and petroleum industries.