نوع مقاله : مقاله پژوهشی

نویسندگان

گروه شیمی، دانشکده‌ی فیزیک و شیمی، دانشگاه الزهرا

چکیده

دی گلیکول آمیدها به طور گسترده‌ای برای استخراج یون‌های لانتانیدها و آکتینیدها از پسماندهای هسته‌ای و افزایش کارایی این ترکیبات در فرایند استخراج مورد توجه قرار دارند. در این پژوهش، تغییرات ساختاری دی گلیکول آمیدها در برهم‌کنش با یون سه ظرفیتی لانتانیم با استفاده از روش‌های نظریه‌ی تابعی چگالی به لحاظ ساختاری، الکترونی و ترمودینامیکی مورد مطالعه قرار گرفته است. در این رابطه، برخی از تغییرات ساختاری در دی گلیکول آمیدها، از جمله جای­گزینی اکسیژن اتری با نیتروژن و اضافه شدن استخلاف متیل و نیز گروه‌های متیلن میان اکسیژن اتری و گروه‌های کربنیلی به زنجیره­ی دی گلیکول آمید بررسی شده است. داده­های ترمودینامیکی محاسبه شده نشان می‌دهد که اضافه کردن گروه‌های متیلن میان اکسیژن اتری و گروه‌های کربنیلی کارایی قدرت استخراج این لیگاندها را کم می­‌کند. علاوه بر این، هگزان نرمال در مقایسه با دودکان حلال مطلوب­تری در فرایند تشکیل کمپلکس است، که در توافق با نتایج تجربی است. برخی مرتبه­‌ها و طول­‌های پیوندی کلیدی در محصولات بررسی و مقادیر انرژی تغییر ساختار لیگاند طی فرایند تشکیل کمپلکس با یون لانتانیم بحث شده است.

کلیدواژه‌ها

عنوان مقاله [English]

Structural, Electronic and Thermochemical Study of Interaction Between Lanthanum Trivalent Ion with Diglycolamide Extractants Using Density Functional Theory

نویسندگان [English]

  • T Hosseinnejad
  • F Mamusi

Department of Chemistry, Faculty of physics & chemistry, Alzahra University

چکیده [English]

Diglycolamides have been widely investigated for the high efficient extraction of lanthanide and actinide ions from nuclear wastes. In the present study, we have mainly investigated the structural changes of diglycolamides and their interaction with trivalent lanthanum cation from the structural, electronic and thermodynamical viewpoints, using density functional theory (DFT) approach. In this line, we have assessed comparatively some structural changes in diglycolamide ligand, including displacement of oxygen ether with nitrogen, using methyl substituent and also adding methylene between oxygen ether and carbonyl functional group. The calculated thermodynamical properties indicate that addition of methylene groups between the ether oxygen and carbonyl functional groups decreases the performance of these ligands in the extraction of lanthanum ions. Moreover, our calculated results demonstrate the thermodynamical preference of using n-hexane as solvent in comparison with dodecane that is in agreement with the experimental observations. In the next step, the trend of variations in the calculated bond order of some selected key bonds through the complexation process has been analyzed. Finally, we have calculated and discussed the deformation energies of ligands through the complexation with the lanthanum cation.

کلیدواژه‌ها [English]

  • Diglycolamide extractants
  • Lanthanum ion
  • Structural changes
  • Density functional theory
  • Thermodynamic functions
[1] S. Bourg, C. Hill, C. Caravaca, C. Rhodes, C. Ekberg, R. Taylor, A. Geist, G. Modolo, L. Cassayre, R. Malmbeck, M. Harrison, G. Angelis, A. Espartero, S. Bouvet, N. Ouvrier, ACSEPT-Partitioning technologies and actinide science: Towards pilot facilities in Europe, Nucl. Eng. Des., 241 (2001) 3427-3435.
 [2] N. Kenneth, M. Charles, M. Jagdish, N.L. Jérôme, Actinide separation science and technology, the chemistry of the actinide and transactinide elements, Springer Netherlands, 4 (2006).
 [3] H. Stephan, K. Gloe, J. Beger, P. Muhl, Liquid-liquid extraction of strontium with amidopodands, Solv. Extr. Ion Exch., 9 (1991)  435-458.
 [4] H. Stephan, K. Gloe, J. Beger, P. Muhl, Liquid-liquid extraction of metal ions with amidopodands, Solv. Extr. Ion Exch., 9 (1991)459-469.
 [5] K. Matloka, A. Gelis, M. Regalbuto, G. Vandegrift, M.J. Scott, Highly efficient binding of trivalent f-elements from acidic media with a C3-symmetric tripodal ligand containing diglycolamide arms, Dalton Trans., 23 (2005) 3719-3721.
 [6] Y. Sasaki, R. Choppin, Solvent Extraction of Eu, Th, U, Np and Am with N, N'-Dimethyl-N, N'-dihexyl-3-oxapentanediamide and Its Ana-logous Compounds, Anal. Sci., 12 (1996) 225-230.
 [7] Y. Sasaki, Y. Sugo, S. Suzuki, T. Kimura, A method for the determination of extraction capacity and its application to N, N, N′, N′-tetraalkylderivatives of diglycolamide-mono-amide/n-dodecane media, Anal. Chim. Acta., 543 (2005) 31-37.
[8] Y. Sasaki, G.R. Choppin, Extraction and mutual separation of actinide (III), (IV), (V) and (VI) ions by N,N΄-dimethyl-N,N΄-dihexyl-3-oxa-pentanediamide and the noyltri-fluoroacetone, J. Radioanal. Nucl. Chem., 246 (1997) 267-273.
 [9] Y. Sasaki, G.R. Choppin, Extraction of Np(V) by N, N΄-dimethyl-N,N΄-dihexyl-3-oxapentane diamide, Radiochim. Acta., 180 (1998) 85-88.
 [10] H. Narita, T. Yaita, K. Tamura, S. Tachimori, Solvent extraction of trivalent lanthanide ions with N,N΄-dimethyl- N,N΄-diphenyl-3-oxa-pentanediamide, Radiochim. Acta., 81 (1998) 223-226.
 [11] H. Narita, S. Tachimori, Study on the extraction of trivalent lanthanide ions with N,N΄-dimethyl- N,N΄-diphenyl-malonamide and diglycolamides, J. Radioanal. Nucl. Chem., 239 (1999) 381-384.
 [12] Y. Sasaki, Y. Sugo, S. Suzuki, S. Tachimori, The novel extractants, diglycolamides, for the extraction of lanthanides and actinides in HNO3-n-dodecane system, Solv. Extr. Ion Exch., 19 (2001)91-103.
 [13] Y. Sasaki, P. Rapold, M. Arisaka, M. Hirata, T. Kimura, C. Hill, G. Cote, An additional insight into the correlation between the distribution ratios and the aqueous acidity of the TODGA system, Solv. Extr. Ion Exch., 25 (2007) 187-204.
 [14] E.P. Horwitz, K.A. Martin, H. Diamond, The influence of the diluents on the distribution behavior of octyl (phenyl)- N,N, diiso-butylcarbamoylmethylphosphine oxide, Solv. Extr. Ion Exch., 6 (1988) 859-888.
 [15] M. Hirata, P. Guilbaud, M. Dobler, S. Tachimori, Molecular dynamics simulations for the complexation of Ln3+ and UO22+ ions with tridentate ligand diglycolamide (DGA), Phys. Chem. Chem. Phys., 5 (2003) 691-695.
 [16] C. Cuillerdier, C. Musikas, P. Hoel, L. Nigond, X. Vitart, Malonamides as new extractants for nuclear waste solutions, Sep. Sci. Technol., 26  (1991) 1229-1244.
 [17] Y. Sasaki, Y. Sugo, K. Morita, K.L. Nash, The effect of alkyl substituents on actinide and lanthanide extraction by diglycolamide compounds, Solv. Extr. Ion Exch., 33 (2015) 625-641.
 [18] H. Suzuki, Y. Sasaki, Y. Sugo, A. Apichaibukol, T. Kimura, Extraction and separation of Am(III) and Sr(II) by N,N,N´,N´-tetraoctyl-3-oxapentanediamide (TODGA), Radiochimica. Acta., 92 (2009) 463-466.
 [19] S.A. El-Reefy, E.A. Mowafy, M.M. Abdel-Badei, H.F. Aly, Extraction of uranium and selected fission products from nitric acid medium by certain diamides, Radiochim. Acta., 77 (1997) 195-200.
 [20] L. Spjuth, J.O. Liljenzin, M.J. Hudson, M.G.B. Drew, P.B. Iveson, C. Madic, Comparison of extraction behaviour and basicity of some substituted malonamides, Solv Extr. Ion Exch., 18 (2000) 1-23.
 [21] L. Nigond, C. Musikas, C. Cuillerdier, Extracting properties of N,N,N'N'-tetraalkyl-2 alkyl propane -1,3 diamides, Solv. Extr. Ion Exch., 12 (1994) 297-323.
 [22] T. Hosseinnejad, T. Kazemi, Complexation of amidocarbamoyl phosphine oxides with Ln+3 (Ln= La, Nd, Pm, Sm and Eu) cation series: structural and thermodynamical features, Radiochim. Acta., 104 (2016) 97-105.
 [23] T. Hosseinnejad, S. Dehghanpour, S. Basiri-nasab, A DFT study on the complexation of La3+ ion with malonamide and diglycolamide ligands, Russ. J. Phys. Chem. A.,  88 (2014) 2004-2011.
 [24] T. Hosseinnejad, S. Nikoo, Computational study on the complexation behavior of tetrapropyldiglycolamide with Ln3+ (Ln= Nd, Pm, Sm, and Eu) cation series, Russ. J. Phys. Chem. A., 89 (2015) 1599-1604.
 [25] M.W. Schmidt, K.K. Baldridge, J.A. Boatz, S.T. Elbert, M.S. Gordon, J.H. Jensen, S. Koseki, N. Matsunaga, K.A. guyen, S.J. Su, T.L. Windus, General Atomic and Molecular Electronic Structure System, J. Comput. Chem., 14 (1993) 1347-1363.
 [26] Y. Zhao, D.G. Truhlar, The M06 suite of density functionals for main group thermochemistry, thermochemical kinetics, noncovalent interactions, excited states, and transition elements: two new functionals and systematic testing of four M06-class functionals and 12 other functionals, Theor. Chem. Acta., 120 (2008) 215-241.
 [27] M. Dolg, H. Stoll, H. Preuss, A combination of quasi-relativistic pseudo-potential and ligand field calculations for lanthanoid compounds,Theor. Chim. Acta., 85 (1993) 441-450.
 [28] S.F. Boys, F. Bernardi, The calculation of small molecular interactions by the differences of separate total energies, Some procedures with reduced errors, Mol. Phys., 19 (1970) 553-560.
 [29] C.Z. Wang,J.H. Lan, Q.Y. Wu, Y.L. Zhao, X.K. Wang, Z.F. Chai, W.Q. Shi, Density functional theory investigations of the trivalent lanthanide and actinide extraction complexes with diglycolamides, Dalton Trans., 43 (2014) 8713-8720.