title: Removal of some cationic dyes from aqueous solutions using magnetic-modified multi-walled carbon nanotubes.
abstract: An adsorbent, magnetic-modified multi-walled carbon nanotubes, was used for removal of cationic dyes crystal violet (CV), thionine (Th), janus green B (JG), and methylene blue (MB) from water samples. Prepared nanoparticles were characterized by SEM, TEM, BET and XRD measurements. The prepared magnetic adsorbent can be well dispersed in the water and easily separated magnetically from the medium after loaded with adsorbate. The influences of parameters including initial pH, dosage of adsorbent and contact time have been investigated in order to find the optimum adsorption conditions. The optimum pH for removing of all the investigated cationic dyes from water solutions was found to be 7.0. The experimental data were analyzed by the Langmuir adsorption model. The maximum predicted adsorption capacities for CV, JG, Th and MB dyes were obtained as 227.7, 250.0, 36.4 and 48.1 mg g(-1), respectively. Desorption process of the adsorbed cationic dyes was also investigated using acetonitrile as the solvent. It was notable that both the adsorption and desorption of dyes were quite fast probably due to the absence of internal diffusion resistance.
authors.affiliation: Faculty of Chemistry, Bu-Ali Sina University, Hamedan, Iran. madrakian@basu.ac.ir
authors.forename: Tayyebeh
authors.initials: T
authors.lastname: Madrakian
authors.forename: Abbas
authors.initials: A
authors.lastname: Afkhami
authors.forename: Mazaher
authors.initials: M
authors.lastname: Ahmadi
authors.forename: Hasan
authors.initials: H
authors.lastname: Bagheri
mesh_terms: D000327:Adsorption; D002412:Cations; D004396:Coloring Agents / Q000302:isolation & purification*; D006863:Hydrogen-Ion Concentration; D007220:Industrial Waste / Q000032:analysis / Q000517:prevention & control*; D059346:Magnets; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D037742:Nanotubes, Carbon / Q000737:chemistry*; D012996:Solutions; D013499:Surface Properties; D013997:Time Factors; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods*; D014961:X-Ray Diffraction
chemical_list: D002412:Cations; D004396:Coloring Agents; D007220:Industrial Waste; D037742:Nanotubes, Carbon; D012996:Solutions; D014874:Water Pollutants, Chemical