Abstract
The degradation of the pesticide metsulfuron methyl induced by excitation of iron(iii) aqua complexes was studied at 365 nm. The process involved the formation of hydroxyl radicals and was shown to depend on Fe(OH)2+ concentration. The second order rate constant of the reaction of metsulfuron methyl and hydroxyl radical was evaluated by laser flash photolysis experiments to k=3.5 × 109 mol−1 L s−1. Various products were formed. Among them 2-amino-4-methoxy-6-methyl-1,3,5-triazine, 2-(carbomethoxy) benzenesulfonamide and hydroxylated derivatives represent the major photoproducts. Compounds arising from the cleavage of the triazine moiety were also found. After prolonged irradiation, a total disappearance of metsulfuron methyl and a complete mineralization of the solution were obtained.
References
Environmental Chemistry of Herbicides, CRC Press, ed. R. Grover and A. J. Cessna, Boca Raton, FL, 1991.
S. D. Faust, O. M. Aly, Water pollution of organic pesticides, J. Am. Water Works Assoc., 1964, 56, 267–279.
S. S. D. Foster, P. J. Chilton, M. E. Stuart, Mechanisms of ground water pollution by pesticides, J. Inst. Water Environ. Manag., 1991, 51, 86–193.
E. Hodgson, P. E. Levi, Pesticides: an important but undersued model for the environmental health sciences, Environ. Health Perspect., 1996, 104, 97–106.
G. C. Galletti, A. Bonetti, G. Dinelli, High performance liquid chromatography determination of sulfonylureas in soil and water, J. Chromatogr. A, 1995, 692, 27–37.
R. Bossi, K. Vejrup, C. S. Jacobsen, Determination of sulfonylurea degradation products in soil by liquid chromatography-ultraviolet detection followed by confirmatory liquid chromatography–tandem mass spectrometry, J. Chromatogr. A, 1999, 855, 575–582.
N. H. Spliid, B. Koppen, Occurrence of pesticides in Danish shallow ground water, Chemosphere, 1998, 377, 1307–1316.
R. K. Juhler, S. R. Sorensen, L. Larsen, Analysing transformation products of herbicide residues in environmental samples, Water Res., 2001, 357, 1371–1378.
A. Knopp, D. Knopp, R. Niessner, ELISA determination of the sulfonylurea herbicide metsulfuron-methyl in different water types, Environ. Sci. Technol., 1999, 33, 358–361.
G. Centi, S. Perathoner, Remediation of water contamination using catalytic technologies, Appl. Catal., 2003, 41, 15–29.
S. Chiron, A. Fernandez-Alba, A. Rodriguez, E. Garcia-Calvo, Pesticide chemical oxidation: state-of-the-art, Water Res., 2000, 342, 366–377.
H. D. Burrows, M. Canle L, J. A. Santaballa, S. Steeken, Reaction pathways and mechanism of photodegradation of pesticides, J. Photochem. Photobiol. B: Biol., 2002, 67, 71–108.
O. Hutzinger, Environmental Photochemistry, The Handbook of Environmental Chemistry, Springer, 1999, vol. 2, part L, 180–215.
O. Legrini, E. Oliveros, A. M. Braun, Photochemical processes for water treatment, Chem. Rev., 1993, 49, 671.
M. Sarakha, M. Bolte, H. Burrows, Electron-transfer oxidation of chlorophenols by uranyl ion excited state in aqueous solution. Steady state ans nanosecond flash photolysis studies, J. Phys. Chem. A, 2000, 104, 3142–3149.
S. Malato, J. Blanco, A. Campos, J. Caceres, C. Guillard, J. M. Herrman, A. R. Fernandez-Alba, Effect of operating parameters on the testing of new industrial titania catalysis at solar pilot plant scale, Appl. Catal. B: Environ., 2003, 42, 349–357.
C. Catastini, M. Sarakha, G. Mailhot, M. Bolte, Iron(iii) aqua complexes as effective photocatalysts for the degradation of pesticides in homogeneous solutions, Sci. Total Environ., 2002, 298, 219–228.
G. Mailhot, M. Sarakha, B. Lavedrine, J. Caceres, S. Malato, Fe(iii)–solar light induced degradation of diethyl phthalate (DEP) in aqeous solutions, Chemosphere, 2002, 49, 525–532.
S. Malato, J. Blanco, J. Caceres, A. R. Fernandez-Alba, A. Aguera, A. Rodriguez, Photocatalytic treatment of water soluble pesticides by photo-Fenton and TiO2 using solar energy, Catal. Today, 2002, 76, 209–220.
H. J Benkelberg, P. Warneck, Photodecomposition of iron(iii) hydroxo and sulfato complexes in aqeous solution: wavelength dependence of OH and SO4− quantum yields, J. Phys. Chem., 1995, 99, 5214–5221.
G. V. Buxton, C. L. Greenstock, W. P. Helman, A. P. Ross, Critical review of rate constants for reactions of hydrated electrons, hydrogen atoms and hydroxyl radicals (˙OH/O˙−) in aqueous solution, J. Phys. Chem., 1988, 17, 513–886.
N. Brand, G. Mailhot, M. Bolte, Degradation photoinduced by Fe(iii): method of alkylphenolethoxylates removal in water, J. Environ. Sci. Technol., 1998, 32, 2715–2720.
H. Park, W. Choi, Visible light and Fe(iii)-mediated degradation of Acid Orange 7 in the absence of H2O2, J. Photochem. Photobiol., A: Chem., 2003, 159, 241–247.
W. Feng, D. Nansheng, Photochemistry of hydrolytic iron(iii) species and photoinduced degradation of organic compounds. A minireview, Chemosphere, 2000, 41, 1137–1147.
P. Mazellier, J. Jirkovsky, M. Bolte, Degradation of diuron photoinduced by iron(iii) in aqueous solution, Pestic. Sci., 1997, 49, 259–267.
Y. Sun, J. Pignatello, Photochemical reactions involved in the total mineralization of 2,4-D by Fe3+/H2O2/UV, J. Environ. Sci. Technol., 1993, 27, 304–310.
S. K. Parrich, J. E. Kauffmann, K. A. Croon, Y. Ishida, K. Ohta, S. Itoh, A new selective herbicide to control annual and perennial weeds in wheat, Br. Crop Prot. Conf.–Weeds, 1995, 57–63.
H. M. Brown, Mode of action, crop selectivity and soil relations of sulfonylurea herbicides, Pestic. Sci., 1990, 29, 263–281.
M. E. Beyer, H. M. Brown, M. J. Duffy, Sulfonylurea herbicide soil relations, Br. Crop Prot. Conf.–Weeds, 1987, 531–540.
Q. Ye, J. Sun, J. Wu, Causes of phytotoxicity of metsulfuron-methyl bound residues in soil, Environ. Pollut., 2003, 126, 417–423.
S. Samanta, R. K. Kole, A. Chowdhury, Photodegradation of metsulfuron methyl in aqueous solution, Chemosphere, 1999, 39, 873–879.
E. Vulliet, C. Emmelin, M. F. Grenier-Loustallot, O. Païssé, J. M. Chovelon, Simulated sunlight-induced photodegradation of triasulfuron and cinosulfuron in aqueous solution, J. Agri. Food Chem., 2002, 50, 1081–1088.
A. K. Bhattacharjee, P. Dureja, light induced transformation of tribenuron-methyl, Chemosphere, 1999, 384, 741–749.
M. Caselli, G. Ponterini, M. Vignali, Irradiation-wavelength dependent photochemistry of the bichromophoric sulfonylurea chlorsulfuron, J. Photochem. Photobiol., A: Chem., 2001, 138, 129–137.
J. G. Calvert and J. M. Pitts, Photochemistry, Wiley, New York, 1996, 783–786.
B. C. Faust, J. Hoigné, Photolysis of Fe(iii)–hydroxy complexes as sources of OH radicals in clouds, fog and rain, Atmos. Environ., 1990, 24A, 79–89.
H. H. Jaffé and M. Orchin, Theory and applications of ultraviolet spectroscopy, Wiley, New York, 1962, ch. 17.
J. J. Anderson, T. M. Priester, L. M. Shalaby, metabolism of metsulfuron-methyl in wheat and barley, J. Agri. Food Chem., 1989, 37, 1429–1434.
Y. Li, W. T. Zimmerman, M. K. Gorman, R. W. Reiser, A. J. Fogiel, P. E. Haney, Aerobic soil metabolism of metsulfuron-methyl, Pestic. Sci., 1999, 55, 434–445.
J. Sabadie, Chemical acidic hydrolysis of metsulfuron methyl, Weed Res., 1990, 30, 413–419.
L. D. Bray, N. E. Heard, M. C. Overman, J. D. Vargo, D. L. King, L. J. Lawrence, A. W. Phelps, Hydrolysis of prosulfuron at pH 5: evidence for a resonance-stabilized triazine cleavage product, Pestic. Sci., 1997, 51, 56–64.
S. P. Ramnani, S. Dhanya, P. K. Bhattacharyya, Pulse radiolytic studies on the reactions of some oxidizing and reducing radicals with sulfanilamide in aqueous, Radiat. Phys. Chem., 1997, 503, 277–282.
D. Behar, B. Behar, Pulse radiolysis studies of aminobenzenesulfonates: formation of cation radicals, J. Phys. Chem., 1991, 95, 7552–7556.
U. Stafford, K. A. Bray, P. V. Kamat, Radiolytic and TiO2-Assisted Photocatalytic Degradation of 4-Chlorophenol. A Comparative Study, J. Phys. Chem., 1994, 98, 6343–6351.
C. von Sonntag, H-P. Schuchmann, The elucidation of peroxyl radical reactions i aqueous solution with the help of radiation-methods, Angew. Chem., Int. Ed. Engl., 1991, 30, 1229–1253.
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Dedicated to Dr. Pierre Boule in recognition of his outstanding contribution to the development of photochemistry in aqueous solution.
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Rafqah, S., Aamili, A., Nelieu, S. et al. Kinetics and mechanism of the degradation of the pesticide metsulfuron methyl induced by excitation of iron(iii) aqua complexes in aqueous solutions: steady state and transient absorption spectroscopy studies. Photochem Photobiol Sci 3, 296–304 (2004). https://doi.org/10.1039/b314001f
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DOI: https://doi.org/10.1039/b314001f