Abstract:
The inorganic montmorillonitic clay material in raw and
modified forms (sodic and fractionated sodic materials) was
evaluated as adsorbent for anionic textile dye (Nylosan Red N-
2RBL). A various characterization using XRD, XRF, AFM,
FTIR, TG, adsorption of methylene blue and pHPCN of the
considered samples was realized. The experimental results show
that, the adsorption was pH dependent with a high adsorption
capacity of NR dye in acidic range. The pseudo-second-order
kinetic model provided the best fit to the experimental data for
the adsorption of dye by clay materials. The equilibrium
adsorption data were analyzed by Langmuir, Freundlich and
Dubinin–Radushkevich isotherm models. The best fit of
experimental data was obtained by the Dubinin–Radushkevich
isotherm model. The maximum adsorption capacity of the raw
clay calculated by the latest isotherm model is 62.05 mg/g. It is
increased in modified forms (170.11 and 201 mg/g for sodic
clay and fractionated sodified clay materials, respectively).
Increasing solution ionic strength (NaCl, KCl, NaNO3, and
Na2SO4) increased significantly the adsorption of dye
