title: Treatment of azo dye-containing wastewater by a Fenton-like process in a continuous packed-bed reactor filled with activated carbon.
abstract: In this work, oxidation with a Fenton-like process of a dye solution was carried out in a packed-bed reactor. Activated carbon Norit RX 3 Extra was impregnated with ferrous sulfate and used as catalyst (7 wt.% of iron). The effect of the main operating conditions in the Chicago Sky Blue (CSB) degradation was analyzed. It was found that the increase in temperature leads to a higher removal of the dye and an increased mineralization. However, it also increases the iron leaching, but the values observed were below 0.4 ppm (thus, far below European Union limits). It was possible to reach, at steady-state, a dye conversion of 88%, with a total organic carbon (TOC) removal of ca. 47%, being the reactor operated at 50°C, pH 3, W(cat)/Q=4.1 g min mL(-1) (W(cat) is the mass of catalyst and Q the total feed flow rate) and a H(2)O(2) feed concentration of 2.25 mM (for a CSB feed concentration of 0.012 mM). The same performance was reached in three consecutive cycles.
authors.affiliation: Chemical Engineering Department, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal.
authors.forename: Isabel
authors.initials: I
authors.lastname: Mesquita
authors.forename: Luís C
authors.initials: LC
authors.lastname: Matos
authors.forename: Filipa
authors.initials: F
authors.lastname: Duarte
authors.forename: F J
authors.initials: FJ
authors.lastname: Maldonado-Hódar
authors.forename: Adélio
authors.initials: A
authors.lastname: Mendes
authors.forename: Luis M
authors.initials: LM
authors.lastname: Madeira
mesh_terms: D000327:Adsorption; D002244:Carbon / Q000737:chemistry; D002384:Catalysis; D004396:Coloring Agents / Q000737:chemistry*; D005296:Ferrous Compounds / Q000737:chemistry; D006861:Hydrogen Peroxide / Q000737:chemistry; D016877:Oxidants / Q000737:chemistry; D010084:Oxidation-Reduction; D016062:Porosity; D014343:Trypan Blue / Q000737:chemistry*; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D002244:Carbon; D004396:Coloring Agents; D005296:Ferrous Compounds; D006861:Hydrogen Peroxide; D016877:Oxidants; D014343:Trypan Blue; D062065:Wastewater; D014874:Water Pollutants, Chemical; C009000:pontamine sky blue; C020748:ferrous sulfate