Langmuir isotherm
In the solid/liquid adsorption process, adsorption of the solute is usually characterized
by either mass transfer (boundary layer diffusion) or intraparticle diffusion or even
both (Ghosh and Bhattacharyya, 2002).
The adsorption data of Rh-B removal from natural diatomite was analyzed by the
Freundlich and Langmuir isotherm models. The Langmuir isotherm model is valid for
monolayer adsorption. The linear equation of the Langmuir isotherm is (Dogan et al.,
2006):
(6)
where, Ce is the equilibrium concentration of RhB in the solution, qe amount of Rh-B
adsorbed at equilibrium, qm Langmuir adsorption capacity, and b Langmuir constant.