title: Enzymatic treatment of sulfonated aromatic amines generated from reductive degradation of reactive azo dyes.
abstract: Anaerobic degradation, an effective treatment process of textile industry effluent, generates sulfonated aromatic amines, which are carcinogenic, mutagenic, and resistant to microbial degradation. These aromatic amines can be effectively removed by oxidative polymerization catalyzed by peroxidase enzyme. The amines, generated in this study from the anaerobic reduction by zero-valent iron of two reactive azo dyes (Reactive Red 2 [RR2] and Reactive Black 5 [RB5]), were successfully removed (90%) by Arthromyces ramosus peroxidase (ARP). For better understanding of the process, enzymatic treatment of two model compounds, diphenylamine (DPA) and 2-amino-8-naphthol-3,6-disulfonic acid (ANDSA), were also studied. Diphenylamine has a similar diarylamine bond as RR2. The ANDSA has a similar structure as the dye reduction products. The secondary amine bond in DPA and RR2 were oxidized by ARP. Enzymatic reaction of sulfonated aromatic amines generated soluble colored compounds, which were removed by coagulant. Optimum reaction parameters were also determined.
authors.affiliation: Environmental Engineering, University of Windsor, Ontario, Canada.
authors.forename: Mousumi Mani
authors.initials: MM
authors.lastname: Biswas
authors.forename: Keith E
authors.initials: KE
authors.lastname: Taylor
authors.forename: Jatinder K
authors.initials: JK
authors.lastname: Bewtra
authors.forename: Nihar
authors.initials: N
authors.lastname: Biswas
mesh_terms: D000693:Anaerobiosis; D001391:Azo Compounds / Q000737:chemistry* / Q000378:metabolism; D001673:Biodegradation, Environmental; D004396:Coloring Agents / Q000737:chemistry* / Q000378:metabolism; D004159:Diphenylamine / Q000737:chemistry / Q000302:isolation & purification; D005658:Fungi / Q000201:enzymology; D006861:Hydrogen Peroxide / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007220:Industrial Waste; D010084:Oxidation-Reduction; D009195:Peroxidase / Q000378:metabolism*; D013783:Textile Industry; D013997:Time Factors; D014874:Water Pollutants, Chemical / Q000737:chemistry* / Q000378:metabolism
chemical_list: D001391:Azo Compounds; D004396:Coloring Agents; D007220:Industrial Waste; D014874:Water Pollutants, Chemical; D004159:Diphenylamine; D006861:Hydrogen Peroxide; D009195:Peroxidase