What are the main points of Langmuir adsorption isotherm?
2.4 The Langmuir isotherm
- The surface consists of a uniform two-dimensional array of identical adsorption sites.
- The probability of adsorbing on or desorbing from a site is independent of the number of nearby molecules (the loading, θ).
- The activation energy for desorption is equal to the heat of adsorption, Q.
Which is better Langmuir and Freundlich?
It was observed that the Freundlich isotherm model described the adsorption process with high coefficient of determination R2, better than the Langmuir isotherm model and for low initial concentration of heavy metal.
What are the three assumptions of the Langmuir isotherm?
The Langmuir adsorption isotherm was derived by the US chemist Irving Langmuir (1881–1957), using the kinetic theory of gases and making the assumptions that: (1) the adsorption consists entirely of a monolayer at the surface; (2) there is no interaction between molecules on different sites and each site can hold only …
How do you explain Freundlich isotherm?
A Freundlich isotherm is a mathematical expression for the adsorption equilibrium between a fluid (liquid or gas) and a solid material.
What are three assumptions in Langmuir isotherm?
What do you mean by Freundlich adsorption isotherm?
The Freundlich equation or Freundlich adsorption isotherm, an adsorption isotherm, is an empirical relationship between the quantity of a gas adsorbed into a solid surface and the gas pressure. This equation is known as Freundlich adsorption isotherm or Freundlich adsorption equation.
Which relation represents Freundlich adsorption isotherm?
The Freundlich Isotherm
| Adsorption isotherm | Equationa |
|---|---|
| Freundlich | Qe = kfCe(1/nf) also used as Qe = kfCen as used by oil processors x/m = KCn |
| Brunauer-Emmet-Teller (BET) | Qe = (BCeQ)/(Ce-Cs)[1 +(B – 1)(Ce/Cs)] |
| Langmuir | Qe = (QbCe)/(1 + bCe) |
| Linear | Qe = KpCe |