title: Activated carbon/Fe(3)O(4) nanoparticle composite: fabrication, methyl orange removal and regeneration by hydrogen peroxide.
abstract: In the water treatment field, activated carbons (ACs) have wide applications in adsorptions. However, the applications are limited by difficulties encountered in separation and regeneration processes. Here, activated carbon/Fe(3)O(4) nanoparticle composites, which combine the adsorption features of powdered activated carbon (PAC) with the magnetic and excellent catalytic properties of Fe(3)O(4) nanoparticles, were fabricated by a modified impregnation method using HNO(3) as the carbon modifying agent. The obtained composites were characterized by X-ray diffraction, scanning and transmission electron microscopy, nitrogen adsorption isotherms and vibrating sample magnetometer. Their performance for methyl orange (MO) removal by adsorption was evaluated. The regeneration of the composite and PAC-HNO(3) (powdered activated carbon modified by HNO(3)) adsorbed MO by hydrogen peroxide was investigated. The composites had a high specific surface area and porosity and a superparamagnetic property that shows they can be manipulated by an external magnetic field. Adsorption experiments showed that the MO sorption process on the composites followed pseudo-second order kinetic model and the adsorption isotherm date could be simulated with both the Freundlich and Langmuir models. The regeneration indicated that the presence of the Fe(3)O(4) nanoparticles is important for a achieving high regeneration efficiency by hydrogen peroxide.
authors.affiliation: Institute of Chemical Technology, Vietnamese Academy of Science and Technology, 01 Mac Dinh Chi, District 1, Ho Chi Minh, Viet Nam. huydoma@vast-hcm.ac.vn
authors.forename: Manh Huy
authors.initials: MH
authors.lastname: Do
authors.forename: Ngoc Hoa
authors.initials: NH
authors.lastname: Phan
authors.forename: Thi Dung
authors.initials: TD
authors.lastname: Nguyen
authors.forename: Thi Thu Suong
authors.initials: TT
authors.lastname: Pham
authors.forename: Van Khoa
authors.initials: VK
authors.lastname: Nguyen
authors.forename: Thi Thuy Trang
authors.initials: TT
authors.lastname: Vu
authors.forename: Thi Kim Phuong
authors.initials: TK
authors.lastname: Nguyen
mesh_terms: D000327:Adsorption; D001391:Azo Compounds / Q000302:isolation & purification*; D002606:Charcoal / Q000737:chemistry*; D005290:Ferric Compounds / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000737:chemistry*; D060526:Magnetic Fields; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D010084:Oxidation-Reduction; D016062:Porosity
chemical_list: D001391:Azo Compounds; D005290:Ferric Compounds; D002606:Charcoal; C000499:ferric oxide; C100258:methyl orange; D006861:Hydrogen Peroxide