where qe (mg/g) and Ce (mg/L) are the amount of adsorbed dye per unit mass of sorbent and
unadsorbed dye concentration in solution at equilibrium, respectively. qmax is the maximum amount of the
adsorbed dye per unit mass of sorbent to form a complete monolayer on the surface bound at high Ce
(mg/g), and K (L/mg) is a constant related to the affinity of the binding sites. The linear form of Langmuir
model is: