CARLOS ALBERTO DA SILVA QUEIROZ
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Artigo IPEN-doc 24190 Preparation of neodymium acetate for use in nuclear area and nanotechnology2017 - QUEIROZ, C.A.S.; PEDREIRA FILHO, W.R.; SENEDA, J.A.Neodymium and its compounds are being increasingly applied in the manufacture of new materials. In nuclear area neodymium isotopes are used in a variety of scientific applications. Nd-142 has been used to produce short-lived Tm and Yb isotopes. Nd-146 has been suggested to produce Pm-147 and Nd-150 has been used to study double beta decay. Due to the several modern applications using nanomaterials, more and more highly rare earth compounds have been demanded. The researches at IPEN uses the experience gained in rare earth separation for the preparation of some pure acetates, purity > 99.9% for application in nanotechnology research. A simple and economical chemical process to obtaining neodymium acetate of high purity is studied. The raw material in the form of mixed rare earths carbonate comes from Brazilian monazite. It is used the technique of strong cationic exchange resin, proper to water treatment, to the neodymium's fractionation and it is achieved a purity of 99.9% in Nd2O3 and yield greater than or equal 80%, with the elution of rare earths by EDTA solution in pH controlled. The complex of EDTA-neodymium is transformed in neodymium oxide, subsequently the oxide is dissolved in acetic acid to obtain the neodymium acetate. The solid salt was characterized via molecular absorption spectrophotometry, mass spectrometry, thermal analysis, chemical analysis and X ray diffraction. In summary the analytical data collected allowed to conclude that the stoichiometric formula for the neodymium acetate prepared is Nd(CH 3COOH)3.1.5H2O.Artigo IPEN-doc 01889 Conditions for the ion exchange separation of gadolinium and samarium from a mixed rare earths carbomates1985 - QUEIROZ, CARLOS A. da S.; ABRAO, ALCIDIOArtigo IPEN-doc 02833 Preparacao de nitrato de cerio de alta pureza1995 - AVILA, D.M.; QUEIROZ, C.A.S.; MUCCILLO, E.N.S.Artigo IPEN-doc 05647 Caracterizacao termoanalitica de peroxido de samario1994 - QUEIROZ, C.A.S.; MATOS, J.R.; ABRAO, A.Artigo IPEN-doc 02689 Separacao de cerio e fracionamento de terras raras a partir dos cloretos mistos1981 - QUEIROZ, C.A.S.; SOOD, S.P.; ABRAO, A.Artigo IPEN-doc 15849 Obtencao experimental de acetato de praseodimio de alta pureza a partir de carbonatos mistos de terras raras2010 - QUEIROZ, C.A. da S.; ROCHA, S.M.R. da; PEDREIRA, W.R.; SENEDA, J.A.; LOBO, R.M.; FILHO, W.S.Artigo IPEN-doc 19322 High purity samarium oxide from mixed rare earth carbonates2013 - QUEIROZ, CARLOS A. da S.; PEDREIRA FILHO, WALTER dos R.; SENEDA, JOSE A.; VASCONCELLOS, MARI E. deArtigo IPEN-doc 08845 Sintese e caracterizacao de precursores a base de lantanio para aplicacao em catalisadores2002 - ROCHA, S.M.R.; QUEIROZ, C.A.S.; ABRAO, A.Artigo IPEN-doc 08844 Recuperacao de torio como nitrato 'mantle grade' usando-se um hidroxido de torio bruto2002 - VASCONCELLOS, M.E.; QUEIROZ, C.A.S.; ABRAO, A.Artigo IPEN-doc 08843 Produção de lantânio de alta pureza para aplicação em P&D2002 - VASCONCELLOS, M.E.; QUEIROZ, C.A.S.; ROCHA, S.M.R.; SENEDA, J.A.; PEDREIRA FILHO, W.R.; SARKIS, J.E.S.; FORBICINI, C.A.L.G.O.; ABRAO, A.