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1.
The extraction behavior of Th(IV) from dilute nitric as well as perchloric acid medium using 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP) and its mixture with tri-n-octyl phosphine oxide (TOPO) was investigated. The species of the type Th(X)(PMBP)3·(HPMBP) and Th(X)(PMBP)3·(TOPO) were extracted for the binary and ternary extraction systems, respectively, where X=NO3− or ClO4−. The presence of 1.25·10−5M Th carrier in the aqueous phase resulted in the extracted species of the type of Th(PMBP)4 and Th(PMBP)4·(TOPO), respectively. The extraction constant (logk ex ) for the binary species Th(PMBP)4 was found to be 6.89±0.01 while the overall extraction constant (logK) for the ternary species Th(PMBP)4·(TOPO) was calculated to be 13.17±0.06.  相似文献   

2.
Synergistic extraction of uranyl ion with 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5 (HPMBP) and oxo donors with widely varying basicity, viz. diphenyl sulfoxide (DPSO), tri-n-butyl phosphate (TBP) and tri-n-octylphosphine-oxide (TOPO) has been studied at various fixed temperatures. Results indicate that the equilibrium constants in the organic phase for addition reactions (KS) with these donors follow their order of basicity (KH) viz. DPSO (0.033)<TBP (0.16)TOPO (8.9) with log KS values of 3.70, 4.28 and 6.45, respectively. The thermodynamic parameters associated with the formation of these systems have been evaluted by the temperature coefficient method. The results indicate that the complex in the organic phase for DPSO and TBP is stabilized only by enthalpy, whereas both enthalpy and entropy contribute to the stabilization of the TOPO complex. Also, enthalpy contribution is more prominent as compared with the UO 2 2+ /HTTA/TOPO system, where both enthalpy and entropy contribute almost equally.  相似文献   

3.
《Analytical letters》2012,45(14):1159-1167
Abstract

The synergic extraction of Ca, Sr, and Ba ions from aqueous solutions into cyclohexane or benzene containing 1- pheny 1 - 3 - methyl - 4 - stearoylpyrazol - 5 - one (HPMSP) and TOPO has been studied. Quantitative extraction (log D>2) was attained at pH>5.4 for Ca, pH>6.5 for Sr, and pH>7.3 for Ba when cyclohexane containing 0.05 M HPMSP and 0.01 M TOPO was used, and the corresoponding values for benzene were 6.5, 7.8, and 8.4. Extracted species were M(PMSP)2(TOPO)3 (M=Ca, Sr, Ba) for cyclohexane and Ca(PMSP)2(TOPO)3 and Sr (or Ba) (PMSP)2(TOPO)2 for benzene.  相似文献   

4.
The liquid extraction of 14 lanthanoids with a 4-benzoyl-3-phenyl-5-isoxazolone (HPBI) alone in CHCl3 as a diluent from perchlorate medium at constant ionic strength μ = 0.1 is investigated. The synergistic solvent extraction of five selected lanthanoid ions (La3+, Nd3+, Eu3+, Ho3+ and Lu3+) with 4-benzoyl-3-phenyl-5-isoxazolone (HPBI) and 5,11,17,23-tetra-tert-butyl-25,26,27,28-tetrakis-(dimethylphosphinoylmethoxy)calix[4]arene, (S) in CHCl3 has been studied too. The stoichiometry of the extracted species was characterised by a classical log–log plot analysis. It was found that the composition of the extracted species with HPBI are Ln(PBI)3 and in the presence of the phosphorus-containing calix[4]arene the lanthanoid ions have been extracted as [Ln(PBI)3S2]. The values of the equilibrium constants and the separation factors have been calculated. The influence of the synergistic agent on the extraction process has been discussed.  相似文献   

5.
采用高温固相反应合成了M5-2xSmxNax(PO4)3F(M=Ca,Sr,Ba)荧光体,研究了其在真空紫外-可见光范围的发光特性。发现在Ca5(PO4)3F中Sm3+的电荷迁移带约在191 nm,在Sr5(PO4)3F中约在199 nm,而在Ba5(PO4)3F中约在204 nm,随着被取代碱土离子半径的增大电荷迁移能量逐渐减小。比较了M5(PO4)3F (M=Ca,Sr,Ba)中Sm3+和Eu3+电荷迁移能量的关系。  相似文献   

6.
The synergic extraction of magnesium, calcium, strongium, barium and lithium into cyclohexane or benzene containing 1-phenyl-3-methyl-4-acyl-pyrazol-5-one (HA) and tri-n-octylphosphine oxide (TOPO) was investigated as a function of pH, HA and TOPO concentration. The extracted species when the 4-benzoyl compound was used, were MA2(TOPO)2 (M = Mg, Ca, Sr), BaA2(TOPO)3 and LiA(TOPO)2. When the 4-trifluoro-acetyl derivatives was used, the extracted species were the same except for SrA2(TOPO)3. Extraction constants for the synergic extractions were calculated.  相似文献   

7.
The systems CaHPO4−MHPO4−H2O (M=Sr, Ba) were studied at 50°C. ForM=Sr, the series of single phases, Ca1−xSrxHPO4 for 0.95<X<0.75 and CaxSr1−xHPO4 for 0.4<X<1 have been prepared. These solid solution were caracterized by their infrared spectra and their crystallographic unit cell parameters. ForM=Ba a new phase Ca2Ba(HPO4)3 has been determined. It was characterized by DRX, IR, ATD and chemical analyses.

Zusammenfassung Bei 50°C wurde das System CaHPO4−MHPO4−H2O (mitM=Sr, Ba) untersucht. FürM=Sr wurden Serien von Einzelphasen erhalten: Ca1−xSrxHPO4 für 0.95<X< 0.75 und CaxSr1−xHPO4 für 0.4<X<1. Diese Mischkristalle wurden anhand ihrer Infrarotspektren und ihrer kristallographischen Elementarzellenparameter charakterisiert. FürM=Ba wurde die neue Phase Ca2Ba(HPO4)3 ermittelt. Sie wurde mittels DRX, IR, ATD und chemischer Analyse charakterisiert.
  相似文献   

8.
Solvent extraction of65zinc,60cobalt and152+154europium from aqueous buffers into benzene containing 4-thiobenzoyl-2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-one (SBMPP) has been investigated in detail (μ=0.1, T=26±1°C). The species extracted and the values of log Kex, where Kex refers to the extraction equilibrium, are ZnL2 (−2.68) CoL2(−3.08) and EuL3(−7.08), where L is the anion of the ligand. The sulfur analog appears to be more effective than the parent ligand 4-benzoyl-2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-one in the extraction of zinc(II) and cobalt(II), whereas the reverse is true with europium(III).  相似文献   

9.
The complexation of 1-[(4-benzothiazolyl)phenyl]-4,7,10,13-tetraoxa-1-aza-cyclopenta-decane with Ba2+ and Ca2+ cations was investigated spectrophotometrically and spectrofluorometrically. The stability constants of the complexes formed are: for Ba2+ logK st=3.17±0.01 (absorption) and logK st=2.95±0.03 (fluorescence); for Ca2+ logK st=3.71±0.02 (absorption) and logK st=3.58±0.05 (fluorescence). Protonation of the ligand leads to fluorescence quenching. AM1 and PPP quantum chemical calculations were used to predict molecular geometry, proton affinities and the spectra of the compounds studied.Dedicated to Prof. Dr. Karl-Heinz Drexhage on the occasion of his 60th birthday  相似文献   

10.
The extraction of radium and barium into a mixture of 1-phenyl-3-methyl-4-benzoylpyrazol-5-one (HPy) and trioctylphosphine oxide (TOPO) in n-hexane or cyclohexane was investigated as a function of pH and TOPO concentration. It was found that the synergistic enhancement of the extraction is caused by the formation of mixed complexes of type M(Py)2 (TOPO)3 and the overall extraction constants of both complexes were calculated.  相似文献   

11.
Summary From extraction experiments and<span style='font-size:12.0pt;font-family:Symbol; mso-bidi-font-family:Symbol'>g-activity measurements, the extraction constant corresponding to the equilibrium Ba2+(aq)+SrL2+(nb)?BaL2+(nb)+Sr2+(aq) taking place in the two-phase water-nitrobenzene system (L= valinomycin; aq= aqueous phase,</o:p>nb= nitrobenzene phase) was evaluated as logKex(Ba2+, SrL2+)=1.3. Furthermore, the stability constant of the valinomycin-strontium complex in nitrobenzene saturated with water was calculated for a temperature of 25 °C: logbnb(SrL2+)=5.4.  相似文献   

12.
Solid electrolytes K3 – 2x M x PO4 (M = Ca, Sr, Ba) are synthesized and the temperature and concentration dependences of their electroconductivity are studied. Adding calcium and strontium stabilizes the high-temperature -form of K3PO4 at room temperature, while barium-containing solid electrolytes undergo an eutectoid decomposition below 430°C. Maximum electroconductivity is exhibited by K3 – 2x Sr x PO4 (7.1 × 10–3 and 1.25 × 10–1 S cm–1 at 300 and 700°C).  相似文献   

13.
From extraction experiments with22Na as a tracer, the extraction constant corresponding to the equilibrium Ba2+(aq)+2NaL+(nb)⇄ ⇄BaL2 2+(nb)+2Na+(aq) taking place in the two-phase water-nitrobenzene system (L=15-crown-5; aq=aqueous phase, nb=nitrobenzene phase) was evaluated as logK ex (Ba2+,2NaL+)=3.3±0.1. Further, the stability constant of the complex BaL2 2+ in nitrobenzene saturated with water was calculated: log βnh(BaL 2 2+ )=16.4±0.1.  相似文献   

14.
Solid solutions of the structure -K4P2O7, which have the composition (K1 – x Rb x )3.8M0.1P2O7(M = Ca, Sr, Cd, Ba) and (K1 – x Rb x )4 – 2y Ca y P2O7(y= 0.025–0.20), are synthesized. The solutions' electroconductivity is studied in the temperature range 400–600°C. The concentration dependences of the conductivity and the activation energy for conduction have extremums at x 0.6, which points to the polyalkaline effect. The effect increases with decreasing radius of cation M2+and with increasing concentration of calcium cations, which is explained by an increased energy nonequivalence of positions in the cation sublattice accessible to alkali ions.  相似文献   

15.
From extraction experiments and γ-activity measurements, the exchange extraction constants corresponding to the general equilibrium \textM 2+ ( \textaq ) + \textSr 2+ ( \textorg ) ? \textM 2+ ( \textorg ) + \text Sr 2+ ( \textaq ) {\text{M}}^{ 2+ } \left( {\text{aq}} \right) + {\text{Sr}}^{ 2+ } \left( {\text{org}} \right) \Leftrightarrow {\text{M}}^{ 2+ } \left( {\text{org}} \right) + {\text{ Sr}}^{ 2+ } \left( {\text{aq}} \right) taking place in the two-phase water–phenyltrifluoromethyl sulfone (abbrev. FS 13) system (M2+ = Mg2+, Ca2+, Ba2+, Cu2+, Zn2+, Cd2+, Pb2+, \textUO22 + {\text{UO}}_{2}^{2 + } , Mn2+, Fe2+, Co2+, Ni2+; aq = aqueous phase, org = FS 13 phase) were evaluated. Furthermore, the individual extraction constants of the M2+ cations in this two-phase system were calculated; they were found to increase in the series of Mg2+, \textUO22 + {\text{UO}}_{2}^{2 + }  < Ca2+, Co2+ < Cd2+, Ni2+ < Zn2+ < Cu2+, Mn2+, Fe2+ < Pb2+ < Ba2+.  相似文献   

16.
In the systems Ca3(PO4)2-MSO4 (M = Sr, Ba), the series of single phase Ca21?3xM2xI(PO4)14?2x(SO4)2x with 0<x<0.15 forM=Sr and 0<x<0.1 forM = Ba have been prepared. These solid solutions, respectively strontium phosphosulfate and barium phosphosulfate, are isostructural with anhydrous tricalcium orthophosphate. They have been characterized by their infrared spectra and their crystallographic unit cell parameters.  相似文献   

17.

Abstract  

From extraction experiments and γ-activity measurements, the exchange extraction constants corresponding to the general equilibrium \textM2 + ( \textaq ) + 1 ·\textSr2 + ( \textnb ) \rightleftarrows 1 ·\textM2 + ( \textnb ) + \textSr2 + ( \textaq ) {\text{M}}^{2 + } \left( {\text{aq}} \right) + {\mathbf{1}} \cdot {\text{Sr}}^{2 + } \left( {\text{nb}} \right) \rightleftarrows {\mathbf{1}} \cdot {\text{M}}^{2 + } \left( {\text{nb}} \right) + {\text{Sr}}^{2 + } \left( {\text{aq}} \right) taking place in the two-phase water–nitrobenzene system (M2+ = Ca2+, Ba2+, Cu2+, Zn2+, Cd2+, Pb2+, UO2 2+, Mn2+, Co2+, Ni2+; 1 = tetraphenyl p-tert-butylcalix[4]arene tetraketone; aq = aqueous phase, nb = nitrobenzene phase) were evaluated. Further, the stability constants of the 1 · M2+ complexes in water-saturated nitrobenzene were calculated; they were found to increase in the cation order Ba2+, Mn2+ < Co2+ < Cu2+, Ni2+ < Zn2+, Cd2+, UO2 2+ < Ca2+ < Pb2+.  相似文献   

18.
The mutual influence of the atoms on the composition of solid fluorine-containing antimony(iii) complexes formed in aqueous solutions in the (MF) x −(M′F) n−x −SbF3 (M, M′=Na, K, Rb, Cs, and NH4;n=1, 2;x=0 to 2), (KNO2) n −(KY) n −SbF3 (Y=F, Cl, SO4;n=0.5, 1), and K2SbF5−K2SbCl5 systems was investigated by elemental, X-ray, and thermogravimetric analyses and by IR and121,123Sb NQR spectroscopy. The isomorphism conditions for fluorine-containing antimony(iii) compounds resulting in the formation of complexes NaM′SbF5·1.5H2O (M′=K and Rb), K2SbF5·1.5H2O, NaCs3Sb4F16·H2O, KsbF3Cl, K2SbF2Cl3 with constant compositions, continuous M x M′2−x SbF5 (0<x<2) and limited M x M′1−x SbF4 (0.25<x<0.75; M, M′=K, Rb, Cs, and NH4) solid solutions or LiF+MSbF4 (M=Na, K, Rb, and Cs), M2SbF5+Cs2SbF5 (M=Na and K) and MSbF4+NaSbF4 (M=Rb and NH4) mechanical mixtures were determined. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 103–108, January, 1999.  相似文献   

19.
The bidentate phosphine oxide compounds bis(diphenylphosphinyl)methane (BDPPM) and bis(diphenylphosphinyl)ethane (BDPPE) were synthesized and the liquid—liquid extraction equilibria of some divalent metal ions such as Co(II), Ni(II), Zn(II) and Cd(II) with 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (HPMBP) and the neutral phosphine oxide compounds were investigated. BDPPM was found to be much more powerful than BDPPE and the monodentate neutral ligand trioctylphosphine oxide (TOPO). The composition of the extracted species were determined by a graphical method to be M(PMBP)2(TOPO)s (s = 2 for Co, Ni, Cd and s = 1 for Zn), M(PMBP)2(BDPPM) and M(PMBP)2(BDPPE). The adduct formation constants between the acylpyrazolone chelates and the neutral ligands were determined and are discussed in terms of the molecular structure.  相似文献   

20.
The extraction of Zn(II) and Cd(II) from thiocyanate solutions with bis-2-ethylhexyl sulphoxide (B2EHSO) in benzene as an extractant has been studied by tracer techniques. For comparison, extraction has also been carried out with tributylphosphate (TBP). The extraction data have been analysed by both graphical and theoretical methods by taking into account complexation of the metal in the aqueous phase by inorganic ligands and plausible complexes extracted into the organic phase. The results demonstrate that Zn(II) is extracted as Zn(SCN)2·2B2EHSO and Zn(SCN)2·2TBP. In the case of Cd(II), the extracted species are Cd(SCN)2·4B2EHSO/4TBP. The synergistic extraction of Zn(II) and Cd(II) with mixtures of 1-phenyl-3-methyl-4-benzoyl-pyrazolone-5 (HPMBP) and B2EHSO or TBP or trioctylphosphine oxide (TOPO) from acetate buffer solutions has also been investigated. Zn(II) is extracted as Zn(PMBP)2·B2EHSO/TBP/TOPO. On the other hand, Cd(II) is found to be not extracted with these mixed-ligand systems under the experimental conditions. These results also demonstrate the mutual separation of Zn(II) and Cd(II) using the synergistic extraction with HPMBP in the presence of various neutral oxodonors.  相似文献   

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