Methyl tertiary-butyl ether (MTBE) is a possible human carcinogen that has been used as a gasoline oxygenate at concentrations of up to 15% by volume for about 45 years in the US. However, its high water solubility has exacerbated spills at gasoline stations, sometimes resulting in local groundwater MTBE contamination levels of over 100 mg/L. Advanced oxidation using Fe0 and H2O2 is a promising technique for mineralizing organic contaminants, but current understanding of the remediation chemistry needs to be improved to facilitate design of subsurface or engineered systems.
A kinetic model for the degradation of MTBE in batch systems applying zero-valent iron (Fe0) andhydrogen peroxide (H2O2) oxidation in aqueous solution was developed. The model includes: H2O2 and water chemistry, iron speciation, and MTBE oxidation reactions. H2O2/water and MTBE degradation equilibrium and reaction rate parameters were taken from the literature. Reaction rate and equilibrium parameters for iron speciation were taken from the literature, or from our prior work. The rate constant for the dissolution of Fe0 was found from this work. The model was compared to experimental data from the literature for MTBE degradation using Fe0/H2O2
SquillaceP. J.Preliminary Assessment of the Occurrence and Possible Sources of MTBE in Groundwater in the United States, 1993-1994. Environmental Science and Technology, 1996. 30(5): p. 1721–1730.
2.
EPA.Achieving Clean Air and Clean Water: The Report of the Blue Ribbon Panel on Oxygenates in Gasoline.1999, U.S. Environmental Protection Agency.
3.
JohnsonR.MTBE, To What Extent Will Past Releases Contaminate Community Water Supply Wells?Environmental Science and Technology, 2000. 34(9): p. 210A–217A.
4.
Maine.The Presence of MTBE and Other Gasoline Compounds in Maine's Drinking Water, A Preliminary Report.1998, Maine Department of Conservation, Department of Environmental Protection, Department of Human Services: Augusta.
5.
PankowJ. F.Urban atmosphere as a non-point source for the transport of MTBE and other volatile organic compounds (VOCs) to shallow groundwater. Environmental Science and Technology, 1997. 31(10): p. 2821–2828.
6.
SquillaceP. J., and MoranM. J.Estimating the Likelihood of MTBE Occurrence in Drinking Water Supplied by Ground-Water Sources in the Northeast and Mid-Atlantic Regions of the United States.2000, U.S. Department of the Interior, U.S. Geological Survey.
7.
Erdem-SenatalarA.Adsorption of Methyl Tertiary Butyl Ether on Hydrophobic Molecular Sieves. Environmental Engineering Science, 2004. 21(6): p. 722–729.
8.
NWRI.Treatment Technologies for Removal of Methyl Tertiary Butyl Ether (MTBE) from Drinking Water: Air Stripping, Advanced Oxidation Processes, Granular Activated Carbon, and Synthetic Resin Sorbents, 2nd Ed., The California MTBE Research Partnership.2000, The California MTBE Research Partnership.
9.
AceroJ. L.MTBE Oxidation by Conventional Ozonation and the Combination Ozone/Hydrogen Peroxide: Efficiency of the Processes and Bromate Formation. Environmental Science and Technology, 2001. 35(21): p. 4252–4259.
10.
CaterS. R.UV/H2O2 Treatment of Methyl tert-Butyl Ether in Contaminated Waters. Environmental Science and Technology, 2000. 34(4): p. 659–662.
11.
StefanM. I., MackJ., and BoltonJ. R.Degradation Pathways during the Treatment of Methyl tert-Butyl Ether by the UV/H2O2 Process. Environmental Science and Technology, 2000. 34(4): p. 650–658.
12.
BarretoR. D., GrayK. A., and AndersK.Photocatalytic Degradation of Methyl-tert-Butyl Ether in TiO2 Slurries: A Proposed Reaction Scheme. Wat. Res., 1995. 29(5): p. 1243–1248.
13.
KangJ. W., and HoffmanM. R.Kinetics and Mechanism of the Sonolytic Destruction of Methyl tert-Butyl Ether by Ultrasonic Irradiation in the Presence of Ozone. Environmental Science and Technology, 1998. 32(20): p. 3194–3199.
14.
Safarzadeh-AmiriA.O3/H2O2 treatment of methyl-tert-butyl ether (MTBE) in contaminated waters. Water Research, 2001. 35(15): p. 3706–3714.
15.
KangJ., and LeeK. H.A Kinetic Model of the H2O2/UV Process for the Treatment of Hazardous Water Chemicals. Environmental Engineering Science, 1997. 14(3): p. 183–192.
16.
O'SheaK. E.The Degradation of MTBE-BTEX Mixtures by Gamma Radiolysis. A Kinetic Modeling Study. Radiat. Phys. Chem., 2002. 65: p. 343–347.
17.
WuT.Gamma Radiolysis of Methyl tert-Butyl Ether: A Study of Hydroxyl Radical Mediated Reaction Pathways. Radiat. Phys. Chem., 2002. 65(4-5): p. 335–341.
18.
BergendahlJ., and ThiesT.Fenton's Oxidation of MTBE with Zero-Valent Iron. Water Research, 2004. 38: p. 327–334.
19.
PignatelloJ. J., and ChapaG.Degradation of PCBs by Ferric Ion, Hydrogen Peroxide and UV Light. Environmental Toxicology and Chemistry, 1994. 13(3): p. 423–427.
20.
EngwallM. A., PignatelloJ. J., and GrassoD.Degradation and Detoxification of the Wood Preservatives Creosote and Pentachlorophenol in Water by the Photo-Fenton Reaction. Water Research, 1999. 33(5): p. 1151–1158.
21.
YehC. K., and NovakJ. T.Effect of hydrogen peroxide on the degradation of methyl and ethyl tert-butyl ether in soils. Water Environment Research, 1995. 67(5): p. 828–834.
22.
Al AnanzehN., BergendahlJ., and ThompsonR. W.Kinetic Model for the Degradation of MTBE by Fenton's Oxidation. Environmental Chemistry, 2006. 3: p. 40–47.
23.
CooperW. F.MTBE and priority contaminant treatment with high energy electron beam injection. Radiation Physics and Chemistry, 2002. 65(4-5): p. 451–460.
24.
CooperW. J.Kinetic modeling of the destruction of methyl tert-butyl ether (MTBE). Radiation Physics and Chemistry, 2003. 67(3-4): p. 523–526.
25.
StefanM. I., HoyA. R., and BoltonJ. R.Kinetics and Mechanism of the Degradation and Mineralization of Acetone in Dilute Aqueous Solution Sensitized by the UV Photolysis of Hydrogen Peroxide. Environmental Science and Technology, 1996. 30(7): p. 2382–2390.
26.
LasagaA. C.Atomic Treatment of Mineral-Water Surface Reactions. In: Mineral-Water Interface Geochemistry, HochellaM. F.Jr., and WhiteA. F. (eds.), 1990, Mineralogical Society of America: Chelsea, MI.
27.
LasagaA. C.CHEMICAL KINETICS OF WATER-ROCK INTERACTIONS. Journal of Geophysical Research, 1982. 89(B6): p. 4009–4025.
28.
NagyK. L., BlumA. E., and LasagaA. C.Dissolution and Precipitation Kinetics of Kaolinite at 80°C and ph 3: The Dependence on Solution Saturation State. Amer. J. Sci., 1991. 291(7): p. 649–686.
29.
CamaJ., AyoraC., and LasagaA. C.The deviation-from-equilibrium effect on dissolution rate and on apparent variations in activation energy. Geochimica et Cosmochimica Acta, 1999. 63(17): p. 2481–2486.
30.
CamaJ.Smectite dissolution kinetics at 80°C and pH 8.8. Geochimica et Cosmochimica Acta, 2000. 64(15): p. 2701–2717.
31.
GanorJ., MogollonJ. L., and LasagaA. C.The effect of pH on kaolinite dissolution rates and on activation energy. Geochimica et Cosmochimica Acta, 1995. 59(6): p. 1037–1052.
32.
GanorJ., MogollonJ. L., and LasagaA. C.Kinetics of gibbsite dissolution under low ionic strength conditions. Geochimica et Cosmochimica Acta, 1999. 63(11-12): p. 1635–1651.
33.
LasagaA. C.Kinetic Theory in the Earth Sciences.1998, Princeton, NJ: Princeton University Press.
34.
PourbaixM.Atlas of Electrochemical Equilibria in Aqueous Solutions.1966, Oxford: Pergamon Press.
35.
GautelierM., OelkersE. H., and SchottJ.An experimental study of dolomite dissolution rates as a function of pH from −0.5 to 5 and temperature from 25 to 80°C. Chemical Geology, 1999. 157(1-2): p. 13–26.
36.
LttgeA., WinklerU., and LasagaA. C.Interferometric study of the dolomite dissolution: a new conceptual model for mineral dissolution. Geochimica et Cosmochimica Acta, 2003. 67(6): p. 1099–1116.
37.
YabusakiS.Multicomponent reactive transport in an in situ zero-valent iron cell. Environmental Science and Technology, 2001. 35(7): p. 1493–1503.
38.
ArienzoM.Iron-mediated reactions of polychlorinated biphenyls in electrochemical peroxidation process (ECP). Chemosphere, 2001. 44(6): p. 1339–1346.
39.
TeelA. L.Comparison of Mineral and Soluble Iron Fenton's Catalysts for the Treatment of Trichloroethylene. Wat. Res., 2001. 35(4): p. 977–984.
40.
BurbanoA. A.Oxidation Kinetics and Effect of pH on the Degradation of MTBE with Fenton Reagent. Water Research, 2005. 39: p. 107–118.
41.
HendersonA. D., and DemondA. H.Long Term Performance of Zero-Valent Iron Permeable Reactive Barriers: A Critical Review. Environmental Engineering Science, 2007. 24(4): p. 401.
42.
NurmiJ. T.Characterization and properties of metallic iron nanoparticles: Spectroscopy, electrochemistry, and kinetics. Environmental Science and Technology, 2005. 39(5): p. 1221–1230.
43.
SnoeyinkV. L., and JenkinsD.Water Chemistry.1980, New York: John Wiley & Sons.
44.
StummW., and MorganJ. J.Aquatic Chemistry. 3rd ed. 1996, New York: Wiley.
