title: Azo dye decolorization assisted by chemical and biogenic sulfide.
abstract: The effectiveness of chemical and biogenic sulfide in decolorizing three sulfonated azo dyes and the robustness of a sulfate-reducing process for simultaneous decolorization and sulfate removal were evaluated. The results demonstrated that decolorization of azo dyes assisted by chemical sulfide and anthraquinone-2,6-disulfonate (AQDS) was effective. In the absence of AQDS, biogenic sulfide was more efficient than chemical sulfide for decolorizing the azo dyes. The performance of sulfate-reducing bacteria in attached-growth sequencing batch reactors suggested the absence of competition between the studied azo dyes and the sulfate-reducing process for the reducing equivalents. Additionally, the presence of chemical reduction by-products had an almost negligible effect on the sulfate removal rate, which was nearly constant (94%) after azo dye injection.
authors.affiliation: Laboratory for Research on Advanced Processes for Water Treatment, Unidad Académica Juriquilla, Instituto de Ingeniería, Universidad Nacional Autónoma de México, Blvd. Juriquilla 3001, Querétaro 76230, Mexico.
authors.forename: Dorian
authors.initials: D
authors.lastname: Prato-Garcia
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Cervantes
authors.forename: Germán
authors.initials: G
authors.lastname: Buitrón
mesh_terms: D001391:Azo Compounds / Q000737:chemistry*; D001673:Biodegradation, Environmental; D019149:Bioreactors; D003116:Color; D004396:Coloring Agents / Q000737:chemistry*; D007700:Kinetics; D015233:Models, Statistical; D010084:Oxidation-Reduction; D013431:Sulfates / Q000737:chemistry; D013440:Sulfides / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods*
chemical_list: D001391:Azo Compounds; D004396:Coloring Agents; D013431:Sulfates; D013440:Sulfides; D014874:Water Pollutants, Chemical