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Potentiality of some Synthesized Benzimidazolo-quinazolinone and Pyrimido-benzimidazole Ligands for Selective Extraction of the Rare Earth Elements

Author Affiliations

  • 1Nuclear Materials Authority, P.O Box 530, El-Maadi, Cairo, EGYPT

Res.J.chem.sci., Volume 3, Issue (9), Pages 30-38, September,18 (2013)


Three synthesized multidentate organic solvents; namely 1,2-dihydro-3H-benzimidazolo [1,2-a] quinazolin - 4 - one (4a), 1,2-dihydro - 2, 2 dimethyl benzimidazolo [1,2-a] quinazolin - 4 (3H) - one(4b) and 3 - (cyclohexane - 1 – on - 2yl)pyrimido[1,2-a] benzimidazole (4c) were examined for their extractive potentiality of the rare earth elements from Kadabora sulfate leach liquor. The influential parameters controlling the extraction process including the extractant type, the sulfuric acid concentration, the contact time, the organic/aqueous ratio and the solvents concentration were determined. It was also found that the extractability of the synthesized multidentate organic compounds (4a, 4b and 4c) for rare earths decreases in the order 4a > 4b > 4c. The effects of the stripping agent type, concentration, contact time and O/A ratio on the stripping efficiency of the rare earth elements from the loaded extractants were also tested. A rare earth cake was finally obtained from the strip solution by the addition of oxalic acid as a precipitating agent


  1. Scargill D., Alcock K., Fletcher J.M., Hesford E. and McKay H.A.C., J. Inorg. Nucl. Chem., 4, 304 (1957)
  2. Pierce T.B. and Peck P.F., Analyst, 88, 217 (1963)
  3. Maestro P. and Huguenin D., Alloys Compd., 255, 520 (1995)
  4. Will J., Mitterdorfer A., Kleinlogel C., Perednis D. and Gauckler L. J., Solid State Ionics, 131, 79 (2000)
  5. Franken K.M., A roast-leach process for extraction of rare earths from complex monazite–xenotime concentrates, Sep. Sc. and Tech., 30 (7), 1941 (1995)
  6. Jhone S., Progress in Drug Research, Search for Pharmaceutically interesting Quinazoline Derivatives, Efforts and Results (1969-1980), ed. Jucker, E., Ed., Birkauser Verlag, Basel, 26, 259 (1982)
  7. Brown D.J., The Chemistry of Heterocyclic Compounds, J. Wiley & Sons, New York (1996)
  8. (a) Brown D. J., Quinazolines, Suppl. I, John Wiley & Sons, New York (1996) (b) Undheim K. and Benneche T.,Comprehensive Heterocyclic Chemistry II, A Review of Literature of 1982–1995, Boulton, A. J., Ed., Katritzky, A. R., Rees, C. W., Scriven, E. F. V., Eds.-in-Chief, Pyrimidines and their benzo derivatives, Elsevier Science, New York, p. 96 (1996) Shaban M. A. E., Taha M. A. M. and Sharshira E. M., Advances in Heterocyclic Chemistry, Katritzky A. R., Ed., Synthesis and biological activities of condensed heterocyclo [n, m-a, b, c] quinazolines, Academic Press, New York, 52, p. 5 (1991) Armarego W. L. F. Advances in Heterocyclic Chemistry, Katritzky A. R., Ed., Quinazolines, Academic Press, New York, 1, p. 253 (1963)
  9. Sahu R., Sondhi S. M. and Gupta B., Extraction And Spectrophotometric Determination of Pd(II) with 3,4,4a,5-Tetrahydro-3,3,4a-Trimethyl-7-(Substituted)-Pyrimido(1,6-A)-Benzimidazole-1-Thiol (PBT), Department of Chemistry, University of Roorkee, Roorkee-247667, India (1994) Talanta, 42(3), 401 (1995)
  10. Lu J, Equilibrium reactions and kinetics studies in the extraction process, PhD thesis, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences (1998)
  11. Preston J.S. and Du Preez A.C., Synergistic effects in solvent extraction systems based on alkylsalicylic acids, IV., Extraction of the trivalent rare-earth metals in the presence of bifunctional C=O, P=O, and S=O compounds, Solv. Extr. Ion Exch., 16, 687 (1998)
  12. Xu G.X., Wang W.Q. and Wu J.G., Extraction chemistry of the nuclear fuel (I), synergistic extraction with chelating and complexing extractants, Atomic Energy Sc. and Tech., 7, 487 (1963)
  13. Abul Haj M., Quirós M., Salas J.M. and Faure R., Structure of a tetranuclear heterometallic Ag(I)-Pt(II) complex with a triazolopyrimidine derivative, Inorg. Chem. Communi., 4, 254 (2004)
  14. Lekkas N., Hadjiliadis N., Garoufis A., Kobe J., Bernhardt P.V. and Tiekink E.R.T., Synthesis and characterization of Pd(II) and Pt(II) complexes with triazolopyrimidine derivatives, The crystal structure of [Pd2L2Cl4] where L = 5,7-dimethyl-1,2,4-triazolo[1,5-a]pyrimidine, Inorg. Chim. Acta, 359, 4297 (2006)
  15. Bou–Maroun E., Boos A. and Goetz–Grandmont G.J., Synergistic extraction of lanthanoids with heterocyclic β-ketoenols and 2,4,6-tri(2-pyridyl)-1,3,5-triazine, TPTZ Part II., Extraction of La(III), Eu(III) and Lu(III) with a bis(4-acyl-5-hydroxypyrazole) and TPTZ, Sep. and purifi. tech., 53, 250 (2007)
  16. Hussein G., El Hazek N., Farag A., and El Hussaini O., Separation of rare earth elements from sulfate leach liquor by heterocyclic nitrogen compound, Jour. of Rare Earths, 26(4), 544 (2008)
  17. Girts K., and Edwin G., C. A., 72, 54978e (1970)
  18. Marczenko Z., Spectrophotometric determination of elements, John Wiley and Sons, New York, (1986)
  19. Powell K.J., Brown P.L., Byrne R.H., Gajda T., Hefter G., Leuz A.K., Sjöberg S. and Wanner H., Chemical speciation of environmentally significant metals with inorganic ligands, Part 4, The Cd2+ + OH–, Cl–, CO32–, SO42–, and PO43– systems, Pure Appl. Chem., 83(5), 1163 (2011)
  20. Paoletti P., Formation of metal complexes with ethylenediamine: a critical survey of equilibrium constants, enthalpyandentropyvalues, Pure Appl. Chem. 56(4), 491–522 (1984) doi:10.1351/pac198456040491
  21. Portanova, R; Lajunen, L.H.J.; Tolazzi, M.; Piispanen, J" Critical evaluation of stability constants for alpha-hydroxycarboxylic acid complexes with protons and metal ions and the accompanying enthalpy changes. Part II. Aliphatic 2-hydroxycarboxylic acids (IUPAC Technical Report), Pure Appl. Chem., 75(4), 495–540 (2003)
  22. Rahmani A., Romero M.A., Salas J.M., Quiros M., and Cienfuegos G.A., A new example of/x3-sulfato coordination in a Cd(II) complex of 5,7-dimethyl [ 1,2,4 ] triazolo [ 1,5-a ] pyrimidine (dmtp), Characterisation and biological activity of several metal complexes of dmtp containing the sulfato anion, Inorg. Chim. Acta, 247, 51 (1997)
  23. Mellor J. W., A comprehensive treatise on inorganic and theoretical chemistry, Vol. V, revised and edited by Parkers G.D. and Phil M.A.D., Longmans, printed in Great Britain, 495 (1960)
  24. Chi R. and Xu Z., A solution chemistry approach to the study of rare earth elements precipitation by oxalic acid, Metall. Material Trans., B, 30B, 189 (1999)