title: Treatment of wastewater from a cotton dyeing process with UV/H2O2 using a photoreactor covered with reflective material.
abstract: Wastewater containing several dyes, including sulfur black from the dyeing process in a textile mill, was treated using a UV/H2O2 process. The wastewater was characterized by a low BOD/COD ratio, intense color and high acute toxicity to the algae species Pseudokirchneriella subcaptata. The influence of the pH and H2O2 concentration on the treatment process was evaluated by a full factorial design 22 with three replicates of the central experiment. The removal of aromatic compounds and color was improved by an increase in the H2O2 concentration and a decrease in pH. The best results were obtained at pH 5.0 and 6 g L(-1). With these conditions and 120 min of UV irradiation, the removal of the color, aromatic compounds and COD were 74.1, 55.1 and 44.8%, respectively. Under the same conditions, but using a photoreactor covered with aluminum foil, the removal of the color, aromatic compounds and COD were 92.0, 77.6 and 59.4%, respectively. Moreover, the use of aluminum foil reduced the cost of the treatment by 40.8%. These results suggest the potential application of reflective materials as a photoreactor accessory to reduce electric energy consumption during the UV/H2O2 process.
authors.affiliation: University Center of Eastern Minas Gerais - Unileste-MG, P.O. Box 63, 35170-056 Coronel Fabriciano, Brazil. claudinei_fmelo@hotmail.com
authors.forename: Claudinei Fernandes
authors.initials: CF
authors.lastname: de Melo
authors.forename: Flavio T
authors.initials: FT
authors.lastname: da Silva
authors.forename: Teresa C B
authors.initials: TC
authors.lastname: de Paiva
mesh_terms: D004396:Coloring Agents; D032561:Cotton Fiber; D006861:Hydrogen Peroxide / Q000737:chemistry*; D007700:Kinetics; D010777:Photochemistry; D013783:Textile Industry; D014466:Ultraviolet Rays
chemical_list: D004396:Coloring Agents; D006861:Hydrogen Peroxide