Electrometric studies on uranyl molybdates as a function of pH

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Shiva Prasad
Jaqueline Viana Barros

Abstract

The formation and composition of uranyl molybdates obtained by the interaction of uranyl acetate and sodium molybdate at specific pH levels 7.6, 5.5 and 4.1 have been studied by employing electrometric techniques involving pH and conductometric titrations. The results provide cogent evidence for the formation of three uranyl molybdates having the molecular formulae UO2O.MoO3, 3UO2O.7MoO3 and 2UO2O.8MoO3 in the vicinity of pH 5.7, 4.6 and 3.8, respectively. Analytical investigations of the compounds have also been carried out which substantiate the results of electrometric study.

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Prasad, S., & Barros, J. V. (1998). Electrometric studies on uranyl molybdates as a function of pH. Eclética Química, 23(1), 59–70. https://doi.org/10.26850/1678-4618eqj.v23.1.1998.p59-70
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Original articles

References

AVESTON, J., ANACKER, E.W., JOHANSON, J. S. Hydrolysis of molybdenum(VI). Ultracentrifugation, acidity measurements, and Raman spectra of polymolybdates. Inorg. Chem., v.3, p.735, 1964.

BRAUER, G. (ed.) Handbook of Preparative Inorganic Chemistry. 2 ed. New York; Academic Press, 1965. v.2, p.1705.

BYE, J. Complex equilibria of molybdates. Ann. Chim. Fr., v 20, p.563, 1945; C. r. Acad. Sci. Paris, v.238, p.239, 1954; Bull. Soc. Chim. Fr., p.1023, 1957.

HABER, J. The Role of Molybdenum in Catalysis. London: Climax Molybdenum Co., 1981.

JANDER, G., JAHR, K. F., HENKESHESHOVEN, W. Z. anorg. Chem., v.194, p.383, 1930. Cited in: MURATA, K., IKEDA, S. Studies on polynuclear molybdates in aqueous solution by laser Raman spectroscopy. Spectrochim. Acta. v.39A, p.787, 1983.

KOPF-MAIER, P., KLOPOTKE, T. J. Cancer Res. Clin. Oncol., v.118, p.216, 1992. Cited in Kirk-Othmer Encyclopedia of Chemical Technology. 4th ed. New York; John Wiley and Sons, 1995. v.16, p.962.

OZEKI, T. ADACHI, H., IKEDA, S. Estimation of the dissolved structures and condensation reactivities of mononuclear molybdenum(VI) species in solution using the UV-vis absorption spectra and molecular orbital calculation DV-X. Bull. Chem. Soc. Jpn., v.69, p.619, 1996.

POPE, M. T. Molybdenum Oxygen Chemistry: Oxides Oxo Complexes and Polyanions. In: LIPPARD, S. J. Progress in Inorganic Chemistry, New York: Interscience, 1991. v.39.

PRASAD, S. Electrometric studies on manganese polyvanadates. An. Acad. bras. Ci., v. 53, p.471, 1981; Electrometric investigations on the formation of different antimonate anions as a function of the pH. Bull. Electrochem., v.6, p.163, 1990; Thiotungstate isopolyanions: An electrometric study. Can. J. Chem., v.59, p.563, 1981; Tungstate isopolyanions: An electrometric study. Quim. Nova, v.17, p.31, 1994.

__________. Formation of antimonites and thioantimonites of cobalt as a function of the pH. Ecl. Quim., São Paulo, v.20, p.35, 1995.

__________. Isopolymolybdates: An electrometric study. X Simp. Bras. Eletroquim. Eletroanal., São Carlos, SP, p.143, 1996.

PRASAD, S. GUIMARÃES, T. L. M. Electrometric investigations on the system acid-molybdate and the formation of heavy metal molybdates. Jour. Braz. Chem. Soc., 1998 (in press).

SASAKI, Y., LINDEQVIST, I., SILLEN, L. G. On the first equilibrium steps in the acidification of the molybdate ions. J. Inorg. nucl. Chem., v.9, p.93, 1959.

SASAKI, Y., SILLEN, L.G. On equilibria in polymolybdate solutions. Acta Chem. Scand., v. 18, p. 1014, 1964.

_____________. Ark. Khemi., v.29, p.253, 1967. Cited in: MURATA, K., IKEDA, S. Studies on polynuclear molybdates in aqueous solution by laser Raman spectroscopy. Spectrochim. Acta. v.39A, p.787, 1983.

SIMPSON, C.H. Amer. Paint. Coating J., p.66, 1992. Cited in Kirk-Othmer Encyclopedia of Chemical Technology. 4th ed. New York; John Wiley and Sons, 1995. v.16, p.961.

STANDEN, A. (Ed.) Kirk-Othmer Encyclopedia of Chemical Technology. 2 ed. New York: Interscience Publishers. 1967. v.13, p.782.

VOGEL, A. I. A Textbook of Quantitative Inorganic Analysis. 3 ed. London: Longmans, 1962, p.(a) 508, (b) 238, (c) 507, (d) 540.