title: H2O2/UV-C treatment of textile preparation wastewater: kinetic investigation on alternative combinations of commercial textile preparation auxiliaries.
abstract: Four different textile preparation effluents were simulated to examine the applicability of the hydrogen peroxide/ultraviolet-C (H2O2/UV-C) advanced oxidation process for the treatment of real textile preparation (desizing, scouring and bleaching) wastewater bearing the non-ionic surfactant nonyl phenol decaethoxylate (NP-10). In the absence of any textile preparation chemical, NP-10 degradation was complete in 15 min (rate coefficient: 0.22 min(-1)) accompanied by 78% chemical oxygen demand (COD) (rate coefficient: 0.026 min(-1)) and 57% total organic carbon (TOC) (rate coefficient: 0.014 min(-1)) removals achieved after 60 min photochemical treatment. H2O2 consumption rates were not significantly affected by the introduction of carbonate and chloride ions (average rate coefficient: 0.032 min(-1)) at pH values <11.5, above which H2O2 dissociation to its conjugate base HO2(-) became pronounced. The organic, phosphonate-based sequestering agents competed with NP-10 for UV-C light absorption and HO* radicals. H2O2/UV-C oxidation of the simulated textile preparation effluent containing 3.0 g L(-1) Cl(-), 1.5 g L(-1) NaOH and 1.0 g L(-1) diethylenetriamine pentamethylene phosphonic acid (DTPMP) resulted in the worst treatment performance due to its high pH and organic carbon content. For this textile preparation effluent, NP-10 abatement was complete in 100min (rate coefficient: 0.018 min(-1)), while COD and TOC removals dropped down to only 16% and 8%, respectively, achieved after 60 min treatment. The highest H2O2/UV-C oxidation efficiency resulting in 34% COD and 28% TOC removals was obtained for the simulated textile preparation effluent comprising of 3.0 g L(-1) Cl(-), 1.5 g L(-1) NaOH and 1.0 g L(-1) 1-hydroxy ethylidene-1,1-diphosphonic acid (HEDP). For this textile preparation effluent, NP-10 degradation was complete after 50 min (rate coefficient: 0.061 min(-1)) exposure to H2O2/UV-C treatment.
authors.affiliation: Istanbul Technical University, Faculty of Civil Engineering, Department of Environmental Engineering, Istanbul, Turkey. arslanid@itu.edu.tr
authors.forename: Idil
authors.initials: I
authors.lastname: Arslan-Alaton
authors.forename: Tugba
authors.initials: T
authors.lastname: Olmez-Hanci
authors.forename: Sarina
authors.initials: S
authors.lastname: Shayin
mesh_terms: D057919:Biological Oxygen Demand Analysis; D002254:Carbonates / Q000737:chemistry; D002712:Chlorides / Q000737:chemistry; D012968:Etidronic Acid / Q000737:chemistry; D006861:Hydrogen Peroxide / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007220:Industrial Waste; D007700:Kinetics; D009943:Organophosphorus Compounds / Q000737:chemistry; D010084:Oxidation-Reduction; D010777:Photochemistry / Q000379:methods; D011092:Polyethylene Glycols; D013783:Textile Industry; D014466:Ultraviolet Rays; D014865:Waste Disposal, Fluid / Q000379:methods*
chemical_list: D002254:Carbonates; D002712:Chlorides; D007220:Industrial Waste; D009943:Organophosphorus Compounds; C042719:diethylenetriaminepenta(methylenephosphonic) acid; C404762:polyoxyethylene(10)nonylphenyl ether; D011092:Polyethylene Glycols; D006861:Hydrogen Peroxide; D012968:Etidronic Acid