Batch kinetic and equilibrium studies of adsorption of Reactive Blue 21 by fly ash and sepiolite

Sorption of SPADNS azo dye on polystyrene anion exchangers: Equilibrium and kinetic studies

“…These results suggest that the pseudo second-order sorption mechanism was predominant and the rate of each ion was controlled by chemisorption [61]. For the pseudo second-order model, the rate constant, k 2 , decreases with an initial dye concentration, while the initial sorption rate, h, increases with the increasing of the initial dye concentration which can be attributed to the increase in the driving force for mass transfer, allowing more dye molecules to reach the surface of the sorbents in a shorter period of time [75]. Fig.…”

Adsorption of hazardous dye crystal violet from wastewater by waste materials

“…The graphs obtained in Langmuir plots further help in the determination of thermodynamic parameters. Gibb's free energy (DG°), change in entropy (DS°), and change in enthalpy (DH°) were calculated using the following relations [50,51]:…”

The effect of clay treatment on remediation of diethylketone contaminated wastewater: Uptake, equilibrium and kinetic studies

“…The large surface area of natural clay particles, the chemical and mechanical stability and the high cation-exchange capacity account for the excellent capacity of the clay to adsorb heavy metals [7,8]. Special attention has been given to vermiculite clay as adsorbent for copper and chromium ions [8], bentonite clay for the removal of a cationic dye [9], kaolin clay to remove Cd(II), Cr(VI), Fe(III) and Ni(II) [10], sepiolite clay as adsorbent of Cd(II), Cr(III) and Mn(II) [11] and as adsorbent of dyes [12].…”