title: Methyl-orange and cadmium simultaneous removal using fly ash and photo-Fenton systems.
abstract: Wastewaters resulting from the textile and dye finishing industries need complex treatment for efficient removal of colour and other compounds existent in the dyeing and rising baths (heavy metals, surfactants, equalizers, etc.). Modified fly ash (FA) mixed with TiO(2) photocatalyst represent a viable option for simultaneous removal of dyes and heavy metals, and the optimized conditions are discussed in this paper for synthetic wastewaters containing methyl-orange (MO) and cadmium. For a cost-effective dye removal process, further tests were done, replacing the photocatalyst with a (photo)Fenton system. The optimized technological parameters (contact time, amount of fly ash and amount of Fe(2+)/H(2)O(2)) allow to reach removal efficiencies up to 88% for the heavy metal and up to 70% for the dye. The adsorption mechanisms and the process kinetic are discussed, also considering the possibility of in situ generation of the Fenton system, due to the fly ash composition.
authors.affiliation: Transilvania University of Brasov, Department of Renewable Energy Systems and Recycling, Eroilor 29, 500036 Brasov, Romania. visamro2000@yahoo.com
authors.forename: Maria
authors.initials: M
authors.lastname: Visa
authors.forename: Anca
authors.initials: A
authors.lastname: Duta
mesh_terms: D000327:Adsorption; D001391:Azo Compounds / Q000737:chemistry* / Q000528:radiation effects; D002104:Cadmium / Q000737:chemistry* / Q000528:radiation effects; D002384:Catalysis; D060729:Coal Ash / Q000737:chemistry*; D004396:Coloring Agents / Q000737:chemistry* / Q000528:radiation effects; D006861:Hydrogen Peroxide / Q000737:chemistry; D007501:Iron / Q000737:chemistry; D014025:Titanium / Q000737:chemistry / Q000528:radiation effects; D014466:Ultraviolet Rays; D014865:Waste Disposal, Fluid / Q000379:methods; D014874:Water Pollutants, Chemical / Q000737:chemistry* / Q000528:radiation effects; D014961:X-Ray Diffraction
chemical_list: D001391:Azo Compounds; D060729:Coal Ash; D004396:Coloring Agents; D014874:Water Pollutants, Chemical; D002104:Cadmium; C009495:titanium dioxide; C100258:methyl orange; D006861:Hydrogen Peroxide; D014025:Titanium; D007501:Iron