NMR relaxometry; aluminum; ascorbic acid; benchtop NMR; chromium; hydrogen peroxide; reduction; relaxation; General Materials Science; General Chemistry
Abstract :
[en] The reduction of K2 Cr2 O7 solutions by H2 O2 was studied by NMR relaxometry and UV-Vis spectroscopy in HCl/KCl buffer (pH2), NaCl/Glycine/HCl buffer (pH3) and sodium acetate/acetic acid buffer (pH4). Because of Cr (III) paramagnetism, 1/T1 and 1/T2 of the solutions increase during the reduction of diamagnetic Cr (VI). This increase is proportional to the produced Cr (III) concentration. Using different initial H2 O2 concentrations, partially reduced Cr (VI) samples were prepared and studied by T1 and T2 relaxometry and by UV-Vis spectroscopy. The correlation between the relaxation rates and the concentration of Cr (VI) remaining in the sample, measured by spectroscopy, was excellent. It was possible, thanks to the measurement of T2 , to study the kinetics of the reduction of K2 Cr2 O7 by H2 O2 in the pH3 and pH4 buffers. The reduction of Cr (VI) by ascorbic acid was successfully monitored by NMR relaxometry in the pH2 buffer. The presence of complexing molecules/ions was shown to drastically influence the Nuclear Magnetic Relaxation Dispersion profiles of reduced K2 Cr2 O7 solutions: both relaxation rates are divided by ~5 when citrate or acetate ions are present and by ~3 in the presence of ascorbic acid. Therefore, the comparison of relaxation results obtained in different reaction mixtures must be done carefully. When all the solutions are set to pH0, which prevents any complexation, the longitudinal and transverse relaxation rates of all samples become comparable. Finally, as a proof of concept for a turbid solution, the kinetics of the reduction of a K2 Cr2 O7 solution by aluminum powder in the pH2 buffer was successfully monitored.
Disciplines :
Physical, chemical, mathematical & earth Sciences: Multidisciplinary, general & others
Author, co-author :
Gossuin, Yves ; Université de Mons - UMONS > Faculté de Médecine et de Pharmacie > Service de Physique biomédicale
P. B. Tchounwou, C. G. Yedjou, A. K. Patlolla, D. J. Sutton, EXS 2012, 101, 133. https://doi.org/10.1007/978-3-7643-8340-4_6
O. B. Akpor, Adv Biosci Bioeng 2014, 2, 37. https://doi.org/10.11648/j.abb.20140204.11
M. Tumolo, V. Ancona, D. De Paola, D. Losacco, C. Campanale, C. Massarelli, V. F. Uricchio, Int J Environ Res Public Health 2020, 17, 5438. https://doi.org/10.3390/ijerph17155438
M. Pettine, L. Campanella, F. J. Millero, Environ Sci Technol 2002, 36, 901. https://doi.org/10.1021/es010086b
W. Van Niekerk, J. J. Pienaar, G. Lachmann, R. Van Eldik, M. Hamza, WSA 2019, 33, 629. https://doi.org/10.4314/wsa.v33i5.184022
I. J. Buerge, S. J. Hug, Environ Sci Technol 1997, 31, 1426. https://doi.org/10.1021/es960672i
C. J. Lin, S. L. Wang, P. M. Huang, Y. M. Tzou, J. C. Liu, C. C. Chen, J. H. Chen, C. Lin, Water Res 2009, 43, 5015. https://doi.org/10.1016/j.watres.2009.08.015
F. Fu, W. Han, Z. Cheng, B. Tang, Desalination Water Treat 2016, 57, 5592. https://doi.org/10.1080/19443994.2015.1006259
M. Gheju, Water Air Soil Pollut 2011, 222, 103. https://doi.org/10.1007/s11270-011-0812-y
Q. Zaib, H. S. Park, D. Kyung, Sci Rep 2021, 11, 13146. https://doi.org/10.1038/s41598-021-92535-y
V. A. Okello, S. Mwilu, N. Noah, A. Zhou, J. Chong, M. T. Knipfing, D. Doetschman, O. A. Sadik, Environ Sci Technol 2012, 46, 10743. https://doi.org/10.1021/es301060q
M. S. Hosseini, F. Belador, J Hazard Mater 2009, 165, 1062. https://doi.org/10.1016/j.jhazmat.2008.10.084
R. T. Pflaum, L. C. Howick, J am Chem Soc 1956, 78, 4862. https://doi.org/10.1021/ja01600a014
R. N. Bose, D. Li, S. Moghaddas, Anal Chem 1991, 63, 2757. https://doi.org/10.1021/ac00023a017
C. A. Green, H. Place, R. D. Willett, J. I. Legg, Inorg Chem 1986, 25, 4672. https://doi.org/10.1021/ic00246a017
J. E. Tackett, Appl Spectrosc, AS 1989, 43, 490.
I. Bertini, M. Fragai, C. Luchinat, G. Parigi, Inorg Chem 2001, 40, 4030. https://doi.org/10.1021/ic010161j
L. Banci, I. Bertini, C. Luchinat, Nuclear and electron relaxation: The magnetic nucleus-unpaired electron coupling in solution, Weinheim, New York, Basel, Cambridge, Wiley-VCH 1991.
F. Kock, L. Colnago, NMR Relaxometry applied to chemical studies of paramagnetic metal cation complexes: Fundamentals and applications, J. Braz. Chem Soc. (2022). https://doi.org/10.21577/0103-5053.20220045
F. V. C. Kock, M. P. Machado, G. P. B. Athayde, L. A. Colnago, L. L. Barbosa, Microchem J 2018, 137, 204. https://doi.org/10.1016/j.microc.2017.10.013
J. Kowalewski, L. Nordenskiöld, N. Benetis, P.-O. Westlund, Prog Nucl Magn Reson Spectrosc 1985, 17, 141. https://doi.org/10.1016/0079-6565(85)80007-8
A. Schlüter, A. Weiss, Z Anal Chem 1973, 266, 177. https://doi.org/10.1007/BF00428058
A. Schlüter, A. Weiss, Anal Chim Acta 1978, 99, 157. https://doi.org/10.1016/S0003-2670(01)84508-6
A. Schlüter, A. Weiss, Anal Chim Acta 1978, 97, 93. https://doi.org/10.1016/S0003-2670(01)83279-7
F. V. C. Kock, L. A. Colnago, Microchem J 2015, 122, 144. https://doi.org/10.1016/j.microc.2015.05.003
F. V. C. Kock, T. Monaretto, L. A. Colnago, Int J Biol Macromol 2017, 98, 228. https://doi.org/10.1016/j.ijbiomac.2017.01.083
A. Kákay, M. W. Gutowski, L. Takacs, V. Franco, L. K. Varga, J Phys a: Math Gen 2004, 37, 6027. https://doi.org/10.1088/0305-4470/37/23/005
X. Niu, J. Dong, X. L. Wang, Y.-F. Yao, Environ Sci Nano 2020, 7, 2823. https://doi.org/10.1039/D0EN00384K
B. Xu, J. Dong, X. Wang, Y. Yao, Magnetic Resonance Lett 2022, 2, 170. https://doi.org/10.1016/j.mrl.2022.06.005
K. Livo, M. Prasad, T. R. Graham, Sci Rep 2021, 11, 290. https://doi.org/10.1038/s41598-020-79441-5
M. Dakkouri, H. Rauscher, N. Nestle, J Chem Educ 2004, 81, 1040. https://doi.org/10.1021/ed081p1040
A. Sanchez-Hachair, A. Hofmann, C R Chim 2018, 21, 890. https://doi.org/10.1016/j.crci.2018.05.002
N. Fogel, J. M. J. Tai, J. Yarborough, J Am Chem Soc 1962, 84, 1145. https://doi.org/10.1021/ja00866a017
A. Dasque, M. Gressier, P.-L. Taberna, M.-J. Menu, Results in chemistry 2021, 3, 100207. https://doi.org/10.1016/j.rechem.2021.100207
C. Gabriel, C. P. Raptopoulou, A. Terzis, V. Tangoulis, C. Mateescu, A. Salifoglou, Inorg Chem 2007, 46, 2998. https://doi.org/10.1021/ic061480j
B. Zümreoğlu-Karan, A. N. Ay, C. Ünaleroğlu, Synthesis Reactiv Inorg Metal-Organic Chem 2002, 32, 1071. https://doi.org/10.1081/SIM-120013021
N. Das, R. Das, Appl Clay Sci 2008, 42, 90. https://doi.org/10.1016/j.clay.2007.11.009
I. Bertini, C. Luchinat, G. Parigi, Adv Inorg Chemistry 2005, 57, 105. 10.1016/S0898-8838(05)57003-X