N,N,N',N'-Tetrabutyl-1,10-phenanthroline-2,9-dicarboxamide as Very Effective Extraction Agent for Trivalent Europium and Americium.

Solvent extraction of microamounts of Eu3+ and Am3+ from water into nitrobenzene by means of a mixture of hydrogen dicarbollylcobaltate (H+B-) and N,N,N',N'-tetrabutyl-1,10-phenanthroline-2,9-dicarboxamide (L) was studied. The equilibrium data were explained assuming that the species HL+, H2L2+, HL+2, ML3+2, and ML3+3 (M3+ = Eu3+, Am3+; L = N,N,N',N'-tetrabutyl-1,10-phenanthroline-2,9-dicarboxamide) are extracted into the nitrobenzene phase. Extraction and stability constants of the cationic complex species in nitrobenzene saturated with water were determined and discussed. From the experimental results it is evident that this effective N,N,N',N'-tetrabutyl-1,10-phenanthroline-2,9-dicarboxamide receptor for the Eu3+ and Am3+ cations could be considered as a potential extraction agent for nuclear waste treatment.

Synergistic extraction of europium and americium into nitrobenzene by using hydrogen dicarbollylcobaltate and dodecaethylene glycol.

Extraction of microamounts of europium and americium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B-) in the presence of dodecaethylene glycol (DDEG, L) has been investigated. The equilibrium data have been explained assuming that the species HL+, H2L2+, ML3+ and MH-1L2+ (M3+ = Eu3+, Am3+; L = DDEG) are extracted into the organic phase. The values of extraction and stability constants of the complex species in nitrobenzene saturated with water have been determined. It was found that in this nitrobenzene medium, the stability constant of the EuL3+ complex is comparable with that of AmL3+.

Solvent extraction of calcium and strontium into nitrobenzene by using a synergistic mixture of hydrogen dicarbollylcobaltate and bis(diphenylphosphino)methane dioxide.

Extraction of microamounts of calcium and strontium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B-) in the presence of bis(diphenylphosphino)methane dioxide (DPPMDO, L) has been investigated. The equilibrium data have been explained assuming that the species HL+, HL2+, ML2(2+), ML3(2+) and ML4(2+) (M2+ = Ca2+, Sr2+) are extracted into the organic phase. The values of extraction and stability constants of the cationic complexes in nitrobenzene saturated with water have been determined. In the considered nitrobenzene medium, it was found that the stability constants of the complexes CaL2(2+), CaL3(2+) and CaL4(2+), where L is DPPMDO, are somewhat higher than those of the corresponding complex species SrL2(2+), SrL3(2+) and SrL4(2+) with the same ligand L.

Synergistic Extraction of Strontium into Nitrobenzene by Using Hydrogen Dicarbollylcobaltate and N,N,N´,N´-Tetracyclohexyl-oxybis(o-phenyleneoxy) diacetamide.

Extraction of microamounts of strontium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B-) in the presence of N,N,N´,N´-tetracyclohexyl-oxybis(o-phenyleneoxy)diacetamide (abbrev. barium ionophore I, L) has been investigated. The equilibrium date have been explained assuming that the species HL+, SrL2+ and SrL2+2 are extracted into the organic phase. The values of extraction and stability constants of the cationic complexes in nitrobenzene saturated with water have been determined.

Solvent Extraction of Calcium into Nitrobenzene by Using an Anionic Ligand Based on Cobalt Bis(Dicarbollide) Anion with Covalently Bonded CMPO Function.

From extraction experiments and γ-activity measurements, the exchange extraction constantcorresponding to the general equilibrium Ca2+(aq) + 2HL(nb) <-> CaL2(nb) + 2H+(aq) taking place in the two-phase water-nitrobenzene (L- = anionic ligand based on cobalt bis(dicarbollide) anion with covalently bonded CMPO function; aq = aqueous phase, nb = nitrobenzene phase) was evaluated as log Kex (Ca2+, 2HL) = 0.0 ± 0.1. Further, the stability constant of the electroneutral complex species CaL2 in water-saturated nitrobenzene was calculated for a temperature of 25 °C : log ßnb (CaL2) = 11.0 ± 0.2.

Synergistic extraction of calcium and strontium into nitrobenzene by using hydrogen dicarbollylcobaltate and n,n´-dimethyl-n,n´-diphenyl-2,6-dipicolinamide.

Extraction of microamounts of calcium and strontium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B-) in the presence of N,N´-dimethyl-N,N´-diphenyl-2,6-dipicolinamide (MePhDPA, L) has been investigated. The equilibrium data have been explained assuming that the species HL+, HL+2, ML2+2 and ML2+3 (M2+ = Ca2+, Sr2+) are extracted into the organic phase. The values of extraction and stability constants of the cationic complex species in nitrobenzene saturated with water have been determined.

Solvent Extraction of Some Divalent Metal Cations into Nitrobenzene by Using a Synergistic Mixture of Strontium Dicarbollylcobaltate and p-tert-Butylcalix[4]arene-tetrakis (N,N-Diethylacetamide).

From extraction experiments and g-activity measurements, the exchange extraction constants corresponding to the general equilibrium M2+(aq) + 1•Sr2+(nb) <-> 1•M2+(nb) + Sr2+(aq) taking place in the two-phase water-nitrobenzene system (M2+ = Ca2+, Ba2+, Cu2+, Zn2+, Cd2+, Pb2+, UO22+, Mn2+, Co2+, Ni2+; 1 = p-tert-butylcalix[4]arene-tetrakis(N,N-diethylacetamide); aq = aqueous phase, nb = nitrobenzene phase) were determined. Further, the stability constants of the 1•M2+ complexes in water-saturated nitrobenzene were calculated; they were found to increase in the series of Cu2+ < Ba2+ < Zn2+ < Ni2+ < UO22+ < Co2+ < Mn2+ < Cd2+ < Ca2+ < Pb2+.

Individual extraction constants of some univalent anions in the two-phase water-phenyltrifluoromethyl sulfone system.

From extraction experiments and g-activity measurements, the extraction constants corresponding to the general equilibrium Cs+(aq) + A- (aq) <-> Cs+(org) + A- (org) taking place in the two-phase water-phenyltrifluoromethyl sulfone (FS 13) system (A-= I-, ClO4-, MnO4-, Br-3, I-3, picrate, tetraphenylborate (BPh-4); aq = aqueous phase, org = FS 13 phase) were evaluated. Furthermore, the individual extraction constants of these 7 anions in the mentioned two-phase system were calculated; they were found to increase in the series of I-< ClO4- < Br-3 < MnO4-, picrate < I-3 < BPh-4.

Solvent extraction of calcium and strontium into nitrobenzene by using a synergistic mixture of hydrogen dicarbollylcobaltate and 2,6-(diphenylphosphino)pyridine dioxide.

Solvent extraction of microamounts of calcium and strontium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B-) in the presence of 2,6-(diphenylphosphino)pyridine dioxide (DPPPDO, L) has been investigated. The equilibrium data have been explained assuming that the species HL+, HL+2, CaL2+2, CaL2+3, SrL2+2, SrL2+3 and SrL2+4 are extracted into the organic phase. The values of extraction and stability constants of the species in nitrobenzene saturated with water have been determined.

Solvent Extraction of Strontium into Nitrobenzene by Using a Synergistic Mixture of Hydrogen Dicarbollylcobaltate and Dibenzo-30-crown-10.

Extraction of microamounts of strontium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B-) in the presence of dibenzo-30-crown-10 (DB30C10, L) has been investigated. The equilibrium data have been explained assuming that the species HL+, SrL2+, SrHL3+ and SrHL3+2 are extracted into the organic phase. The values of extraction and stability constants of the cationic complexes in nitrobenzene saturated with water have been determined.

Synergistic extraction of europium into nitrobenzene by using hydrogen dicarbollylcobaltate and 2, 6 - (diphenylphosphino)pyridine dioxide.

Solvent extraction of microamounts of europium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B-) in the presence of 2, 6 - (diphenylphosphino)pyridine dioxide (DPPPDO, L) has been investigated. The equilibrium data have been explained assuming that the species HL+, HL+2, EuL3+3 and EuL3+4 are extracted into the organic phase. The values of extraction and stability constants of the species in nitrobenzene saturated with water have been determined.

Distribution of Microamounts of Cesium in the Two-Phase Water-HCl-Nitrobenzene-2,3-Naphtho-15-crown-5-Hydrogen Dicarbollylcobaltate Extraction System.

Extraction of microamounts of cesium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B-) in the presence of 2,3-naphtho-15-crown-5 (N15C5, L) has been investigated. The equilibrium data have been explained assuming that the complexes HL+, HL+2, CsL+ and CsL+2 are extracted into the organic phase. The values of extraction and stability constants of the species in nitrobenzene saturated with water have been determined.

Extraction of Calcium and Strontium into Phenyltrifluoromethyl Sulfone by Using Synergistic Mixture of Hydrogen Dicarbollylcobaltate and "Classical" CMPO.

Solvent extraction of microamounts of calcium and strontium by a phenyltrifluoromethyl sulfone (FS 13) solution of hydrogen dicarbollylcobaltate (H+B-) in the presence of octyl-phenyl-N,N-diisobutylcarbamoylmethyl phosphine oxide ("classical" CMPO, L) has been investigated. The equilibrium data have been explained assuming that the species HL+, HL2+, ML2+, ML2+2 and ML2+3 (M2+ = Ca2+, Sr2+) are extracted into the organic phase. The values of extraction and stability constants of the cationic complex species in FS 13 saturated with water have been determined. In the considered FS 13 medium, it was found that the stability constants of the complex species CaL2+n, where n = 1, 2, 3 and L is "classical" CMPO, are higher than those of the corresponding complexes SrL2+n.

Solvent extraction of barium into nitrobenzene by using hydrogen dicarbollylcobaltate in the presence of slovafol 909.

Extraction of microamounts of barium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B-) in the presence of Slovafol 909 (L) has been investigated. The equilibrium data have been explained assuming that the species HL+, HL+2, BaL2+ and BaL2+2 are extracted into the organic phase. The values of extraction and stability constants of the complex species in nitrobenzene saturated with water have been determined.

Synergistic effect of ligating and ionic functions, prearranged on a calix[4]arene.

The covalent attachment of two CMPO-functions and two anionic Cosan groups to the narrow rim of tert-butylcalix[4]arene leads to a dramatic increase of the extraction efficiency for the cone isomer; Am(3+) is removed from 5 x 10(-8) M solution to more than 99% by a single extraction step with a 3 x 10(-6) M solution of the calixarene.