title: Removal of diazo dye Direct Red 23 from aqueous solution using zero-valent iron nanoparticles immobilized on multi-walled carbon nanotubes.
abstract: The present study immobilized nanoscale zero-valent iron (nZVI) on multi-walled carbon nanotubes (MWCNTs) to enhance the reactivity of nZVI and prevent its aggregation. This novel composite (nZVI/MWCNT) was characterized by scanning electron microscopy and X-ray diffraction. The results showed that nZVI particles dispersed on the surface of the MWCNTs. The composite was used to remove the diazo dye Direct Red 23 from aqueous solution. The effects of nZVI to MWCNT mass ratio, nanocomposite content, solution pH, initial dye concentration and temperature were studied. The optimum nZVI/MWCNT mass ratio was 1:3. Batch experiments suggest that degradation efficiency decreased as the initial dye concentration increased and increased as the nanocomposite content increased, decreasing the pH from 8 to 4. The reaction followed a pseudo-first-order model under the operational conditions investigated in this study.
authors.affiliation: Department of Chemistry, Islamic Azad University, North Tehran Branch, P.O. Box 1913674711, Tehran, I.R. Iran E-mail: nafisehmansoriieh@yahoo.com.
authors.forename: Mahmoud
authors.initials: M
authors.lastname: Reza Sohrabi
authors.affiliation: Department of Chemistry, Islamic Azad University, North Tehran Branch, P.O. Box 1913674711, Tehran, I.R. Iran E-mail: nafisehmansoriieh@yahoo.com.
authors.forename: Nafiseh
authors.initials: N
authors.lastname: Mansouriieh
authors.affiliation: Department of Chemistry, Islamic Azad University, North Tehran Branch, P.O. Box 1913674711, Tehran, I.R. Iran E-mail: nafisehmansoriieh@yahoo.com.
authors.forename: Morteza
authors.initials: M
authors.lastname: Khosravi
authors.affiliation: Department of Chemistry, Islamic Azad University, North Tehran Branch, P.O. Box 1913674711, Tehran, I.R. Iran E-mail: nafisehmansoriieh@yahoo.com.
authors.forename: Mohsen
authors.initials: M
authors.lastname: Zolghadr
mesh_terms: D000813:Anilides / Q000737:chemistry*; D001391:Azo Compounds / Q000737:chemistry*; D002244:Carbon; D007501:Iron / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D053761:Nanocomposites; D053758:Nanoparticles; D037742:Nanotubes, Carbon / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D000813:Anilides; D001391:Azo Compounds; D037742:Nanotubes, Carbon; D014874:Water Pollutants, Chemical; C506598:1-(2-methoxy-5-nitrophenylazo)-2-hydroxy-3-(3-nitrophenylcarbamoyl)naphthalene; D002244:Carbon; D007501:Iron