| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 150048 | Chemical Engineering Journal | 2012 | 8 Pages |
In this study, both uncalcined (MgNiAl–CO3) and calcined (MgNiAl–C) hydrotalcites were used in the adsorption of methyl orange (MO) from aqueous solution as an anionic dye in a batch system. Various conditions such as initial dye concentration, adsorbent dosage, contact time, solution pH, and temperature were investigated. The adsorption kinetics was studied using classic equations of pseudo-first-order, -second-order and intraparticle diffusion models. The dynamical data fit well with the pseudo-second-order kinetic model. The positive value of the changes in enthalpy (ΔH°), the negative value of Gibbs free energy (ΔG°), showed that the adsorption is endothermic and spontaneous for all the studied temperatures. The equilibrium adsorption data were analyzed using three non linear adsorption models: Langmuir, Freundlich and Redlich–Peterson. The results showed that Langmuir and Redlich–Peterson isotherms fit the experimental results very well with high correlation coefficients. The Langmuir isotherm model exhibited a maximum adsorption capacity qmax of 375 mg/g for the calcined MgNiAl–C. This result is of practical interest, with respect to the selection of sorbents, to optimize aquatic environment remediation technologies.
► Removal of dye from water and wastewaters using low cost adsorbents. ► Development of kinetic models. ► Testing of isotherms. ► Evaluation of thermodynamic parameters.
