title: Improvement of the robustness of solar photo-Fenton processes using chemometric techniques for the decolorization of azo dye mixtures.
abstract: The aim of this study was to propose and to evaluate a strategy based on chemometric tools to improve the robustness of photo-Fenton processes during decolorization of mixtures of sulfonated azo dyes. The strategy consisted of three stages: quantification, reagent dose selection and robustness analysis. The partial least square method was used for the simultaneous quantification of acid orange 7, acid red 151, and acid blue 113, in a mixture, by using UV-visible spectra. Then, a central composite design was applied to set the best reagent dose (Fe(2+) and H2O2) to obtain a decolorization of 97% for each dye. The application of the strategy allowed to predict the concentration of each dye and to select the best reagent dose to decolorize mixtures of sulfonated dyes. Also with the application of the developed strategy, a reduction of peroxide from 33 to 65% was obtained and the undesirable reactions were reduced. It was observed that the variation of dye concentrations do not affected the percentage of decolorization.
authors.affiliation: Laboratory for Research on Advanced Processes for Water Treatment, Instituto de Ingeniería, Unidad Académica Juriquilla, Universidad Nacional Autónoma de México, Blvd. Juriquilla 3001, Campus UNAM Juriquilla, Querétaro 76230, Mexico.
authors.forename: Dorian
authors.initials: D
authors.lastname: Prato-Garcia
authors.forename: Germán
authors.initials: G
authors.lastname: Buitrón
mesh_terms: D001391:Azo Compounds / Q000737:chemistry*; D001557:Benzenesulfonates / Q000737:chemistry; D006861:Hydrogen Peroxide / Q000737:chemistry; D007501:Iron / Q000737:chemistry; D009281:Naphthalenes / Q000737:chemistry; D014466:Ultraviolet Rays
chemical_list: C479461:Acid Red-151; D001391:Azo Compounds; D001557:Benzenesulfonates; D009281:Naphthalenes; C015967:Levanol Fast Cyanine 5RN; D006861:Hydrogen Peroxide; D007501:Iron; C014722:2-naphthol orange
keywords: Azo dye; Chemometric; Photo-Fenton; Response surface methodologies; Spectrophotometry