title: Application of central composite face-centered design and response surface methodology for the optimization of electro-Fenton decolorization of Azure B dye.
abstract: OBJECTIVE
  The aim of this work was to improve the ability of electro-Fenton technique for the remediation of wastewater contaminated with synthetic dyes using a model azo dye such as Azure B.
  
  
  METHODS
  Batch experiments were conducted to study the effects of main parameters, such as dye concentration, electrode surface area, treatment time, and voltage. In this study, central composite face-centered experimental design matrix and response surface methodology were applied to design the experiments and evaluate the interactive effects of the four studied parameters. A total of 30 experimental runs were set, and the kinetic data were analyzed using first- and second-order models.
  
  
  RESULTS
  The experimental data fitted to the empirical second-order model of a suitable degree for the maximum decolorization of Azure B by electro-Fenton treatment. ANOVA analysis showed high coefficient of determination value (R(2) = 0.9835) and reasonable second-order regression prediction. Pareto analysis suggests that the variables, time, and voltage produce the largest effect on the decolorization rate.
  
  
  CONCLUSIONS
  Optimum conditions suggested by the second-order polynomial regression model for attaining maximum decolorization were dye concentration 4.83 mg/L, electrode surface area 15 cm(2), voltage 14.19 V, and treatment time of 34.58 min.
authors.affiliation: Department of Chemical Engineering, University of Vigo, Campus As Lagoas, Marcosende, Vigo, Spain.
authors.forename: E
authors.initials: E
authors.lastname: Rosales
authors.forename: M A
authors.initials: MA
authors.lastname: Sanromán
authors.forename: M
authors.initials: M
authors.lastname: Pazos
mesh_terms: D000704:Analysis of Variance; D001399:Azure Stains / Q000737:chemistry*; D004396:Coloring Agents / Q000737:chemistry*; D055664:Electrochemical Techniques / Q000379:methods*; D004566:Electrodes; D007700:Kinetics; D015233:Models, Statistical; D012044:Regression Analysis; D015203:Reproducibility of Results; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D001399:Azure Stains; D004396:Coloring Agents; D014874:Water Pollutants, Chemical; C025819:Azure B