Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
4985036 | Journal of Colloid and Interface Science | 2017 | 9 Pages |
Magnetic hydroxyapatite-immobilized oxidized multi-walled carbon nanotubes (mHAP-oMWCNTs), an excellent adsorbent for Pb(II) and methylene blue (MB) removal, was synthesized in the present work. It was characterized by SEM, XRD, FTIR, BET, TGA and zeta potential analysis. mHAP-oMWCNTs displayed better adsorption performance than mHAP, mMWCNTs and HAP-oMWCNTs. The adsorption of Pb(II) and MB mainly depend on the ion-exchange property of HAP and the abundant oxygenic functional groups on oMWCNTs surface. Besides, good magnetic performance of mHAP-oMWCNTs makes it easy to achieve the solid-liquid separation. The adsorption kinetic data described well with the pseudo-second-order model and the equilibrium data fitted well with Frendlich and Langmuir isotherms for Pb(II) and MB, respectively. The maximum adsorption capacity was 698.4 mg gâ1 for Pb(II) and 328.4 mg gâ1 for MB from Langmuir isotherm. Thermodynamic studies (ÎG < 0, ÎH > 0, ÎS > 0) implied the both adsorption was endothermic and spontaneous process. Furthermore, the excellent reusability of mHAP-oMWCNTs was confirmed by the desorption experiments. All the results showed mHAP-oMWCNTs has a promising application in water treatment.
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