Degradation of aniline by Fe²⁺-activated persulfate oxidation at ambient temperature

Abstract

The aniline degradation by persulfate activated with ferrous ion (Fe²⁺) was investigated in batch reactor at ambient temperature. The experimental factors in aqueous solutions including persulfate concentration, Fe²⁺ concentration, pH and ionic strength level were discussed. It is demonstrated that, aniline degradation rate increases with increasing persulfate concentration, but much more ferrous ion inhibits the aniline degradation. When the aniline concentration is 0.10 mmol/L, the maximum aniline degradation occurs at the S₂O₈²⁻ to Fe²⁺ molar ratio of 250/5 at pH 7.0. In the pH range of 5.0–8.5, increasing pH causes higher aniline degradation. What’s more, the increase of ionic strength in solution causes inhibiting in the reaction. Produced intermediates during the oxidation process were identified using gas chromatography-mass spectrometry (GC-MS) technology. And degradation pathways of aniline were also tentatively proposed.

Keywords

aniline / ferrous ion / persulfate / degradation

References

[1] KaoC M, HuangK D, WangJ Y, ChenT Y, ChienH Y. Application of potassium permanganate as an oxidant for in situ oxidation of trichloroethylene-contaminated groundwater: A laboratory and kinetics study [J]. Journal of Hazardous Materials, 2008, 153: 919-927

[2] MecozziR, PalmaL D, MerliC. Experimental in situ chemical peroxidation of atrazine in contaminated soil [J]. Chemosphere, 2006, 62: 1481-1489

[3] YangS-y, WangP, YangX, WeiG, ZhangW-y, ShanLiang. A novel advanced oxidation process to degrade organic pollutants in wastewater: Microwave-activated persulfate oxidation [J]. Journal of Environmental Sciences, 2009, 21: 1175-1180

[4] HuangK-c, ZhaoZ-q, HoagG E, DahmaniA, BlockP A. Degradation of volatile organic compounds with thermally activated persulfate oxidation [J]. Chemosphere, 2005, 61: 551-560

[5] AnipsitakisG P, DionysiouD D. Radical generation by the interaction of transition metals with common oxidants [J]. Environment Science Technology, 2004, 38(13): 3705-3712

[6] HuieR E, CliftonC L, NetaP. Electron transfer rates and equilibria of the carbonate and sulfate radicals anions [J]. International Journal of Radiation Applications and Instrumentation Part C: Radiation Physics and Chemistry, 1991, 38(5): 477-481

[7] TravinaO A, KozlovY N, PurmalA P, KodkoiY A. Synergism of the action of the sulfite oxidation initiators, iron and peroxydisulfate ions [J]. Russian Journal of Physics and Chemistry, 1999, 73: 1215-1219

[8] BuxtonG V, MaloneT N, SalmonG A. Reaction of SO₄^−· with Fe²⁺, Mn²⁺ and Cu²⁺ in aqueous solution [J]. Journal of the Chemical Society, Faraday Transactions, 1997, 93: 2893-2897

[9] BuxtonG V, BarlowS, McgowanS, SalmonG A, WiliamsJ E. The reaction of the SO₃^−· radical with Fe(II) in acidic aqueous solution-A pulse radiolysis study [J]. Physical Chemistry Chemical Physics, 1999, 1: 3111-3116

[10] LiJ, XieC-juan. Study on aerobic co-metabolic degradation of aniline in wastewater [J]. Chinese Journal of Environmental Engineering, 2007, 1(6): 51-55

[11] ZhangY-q, HuangW-l, FennellD E. In situ chemical oxidation of aniline by per sulfate with iron(II) activation at ambient temperature [J]. Chinese Chemical Letters, 2010, 21: 911-913

[12] PenningtonD E, HaimA. Stoichiometry and mechanism of the chromium(II) peroxydisulfate reaction [J]. Journal of the American Chemical Society, 1968, 90(14): 3700-3704

[13] NormanR O C, StoreyP M, WestP R. Electron spin resonance studies. Part XXV: Reactions of sulphate radical anion with organic compounds [J]. Journal of the Chemical Society B, 19701087-1095

[14] HayonE, TreininA, WilfJ. Electronic spectra, photochemistry, and autoxidation mechanism of the sulfite-bisulfite-pyrosulfite systems: The SO₂⁻, SO₃⁻, SO₄⁻ and SO₅⁻ radicals [J]. Journal of the American Chemical Society, 1972, 91(01): 47-57

[15] LiangC-j, WangZ-s, BruellC J. Influence of pH on persulfate oxidation of TCE at ambient temperatures [J]. Chemosphere, 2007, 66: 106-113

[16] HuangK-c, CouttenyeR A, HoagG E. Kinetics of heat-assisted persulfate oxidation of methyl tert-butyl ether (MTBE) [J]. Chemosphere, 2002, 49: 413-420

[17] LiS-x, WeiD, MakN-k, CaiZ-w, XueX-r, LiH-b, JiangYue. Degradation of diphenylamine by persulfate: Performance optimization, kinetics and mechanism [J]. Journal of Hazardous Materials, 2009, 164: 26-31

[18] BrillasE, MurE, SauledaR, ÁnchezL S, PeralJ Â, ÁnechbX D, CasadocJ. Aniline mineralization by AOP’s: Anodic oxidation, photocatalysis, electro-Fenton and photoelectro-Fenton processes [J]. Applied Catalysis B: Environmental, 1998, 16: 31-42

[19] SauledaR, BrillasE. Mineralization of aniline and 4-chlorophenol in acidic solution by ozonation catalyzed with Fe₂O and UVA light [J]. Applied Catalysis B: Environmental, 2001, 29: 135-145

[20] CanleL M, SantaballaJ A, VullietE. On the mechanism of TiO₂-photocatalyzed degradation of aniline derivatives [J]. Journal of Photochemistry and Photobiology A: Chemistry, 2005, 175: 192-200