Synergistic Extraction Of Cobalt Research Articles

Methyl-isobutyl ketone and 1-octanol as synergistic agents and phase modifiers in solvent extraction of cobalt(II) by the N-(2-hydroxybenzylidene)aniline from sulfate medium

The synergistic solvent extraction of cobalt(II) from sulfate medium with N-(2-hydroxybenzylidene) aniline in association of two synergistic agents, the methyl-isobutyl ketone (MIBK) and 1-octanolin chloroform at 25 °C, has been studied. Synergistic and antagonistic effects are observed for the title metal at low and high concentration ratios of the synergistic agents. The synergistic extraction of cobalt(II) with the mixtures has been investigated with the methods of slope analysis. The extracted species with the mixtures are CoL2(S)2 and CoL2 (HL) (S) (L, denoted N-(2-hydroxybenzylidene) aniline ion and S denoted MIBK or 1-octanol).

Synergistic extraction of cobalt and nickel ions by supported liquid membranes with a mixture of TIOA and TBP

In this work, the selective separation of cobalt from acidic media, containing both equimolar and non-equimolar mixtures of cobalt and nickel by supported liquid membranes (SLMs), was investigated using Alamine 308 (tri-isooctylamine, TIOA) as the carrier. The liquid membrane consisted of the desired concentration of an extractant (Alamine 308), a modifier (TBP), and a diluent (chloroform). The membrane support was microporous hydrophobic polypropylene Celgard 2500. Parameters, such as the feed solution pH, modifier (TBP) concentration, temperature, stirring speeds, extractant (Alamine 308) concentration, stripping solution type, and the complexing reagent (NH4SCN) concentration were experimentally studied and the optimum conditions were determined. The permeation coefficients (P) and initial fluxes of cobalt were calculated. A separation factor of cobalt over nickel was calculated from the experimental measurements.

Synergistic Extraction of Cobalt(II) by Mixtures of Bis(2-Ethylhexyl)Phosphoric Acid and LIX 860

The extraction of Co(II) from 1.0 M KNO3 medium by mixtures of HDEHP (bis-2-ethylhexylphosphoric acid) and LIX 860 (5-dodecylsalicylaldoxime) dissolved in toluene has been studied. The effects of pH, metal, and extractant mixture concentrations on the extraction behavior have been examined. Synergistic extraction of the metal ion with the binary mixture of extractants has been found. Experimental results have been treated graphically and numerically by means of the Letagrop-Distr program and can be explained by assuming the extraction of two mixed complexes of general stoichiometry CoR2(HR)(HL) and CoR2(HR)(HL)3, HR being bis-2-ethylhexylphosphoric acid and HL standing for 5-dodecylsalicylaldoxime. The corresponding extraction constant values have also been determined.

SYNERGISTIC EXTRACTION OF COBALT(II) WITH MIXTURE OF ACYL-PYRAZOLON AND CROWN-ETHER IN STRONSIUM(II) ENVIRONMENT

Synergistic extraction of cobalt(II) with mixture of acyl-pyrazolon (HL) and crown-ether (E) in the Sr(NO3)2 environment has been studied. In this research, HPMBP (phenyl-1-methyl-3-benzoil-4-pyrazolon-5) was used, with three different kinds of crown-ether, i.e. (benzo-15-crown-5), DB18C6 (dibenzo-18-crown-6) and DB24C8 (dibenzo-24-crown-8), in chloroform. In the bulk environment of stronsium, a cobalt coextraction and stronsium occured with species ESrNO3+,Co(PMBP)3-, and E = B15C5, while Co(PMBP)2E and ESr,Co(PMBP3)2, with E = DB18C6. There was no coextraction when using crown-ether DB24C8, with the extracted species Co(PMBP)2E. Values of extraction constant presented in log Kex were -6.08 (B15C5), - 4.51, -12.55 (DB18C6), and - 4.57 (DB24C8), respectively. Keywords: synergistic, cobalt (II), strontium (II), coextraction.

Synergistic extraction of cobalt (II) by beta hydroxy naphthaldoxime and neutral donors.

Liquid - liquid extraction of Cobalt (II) from aqueous hydrochloric acid medium by the use of oxime derivative of beta-hydroxy naphthaldehyde in o-xylene medium is being reported. The ligand was synthesized and characterized in our laboratory. The typical pH range of extraction of Co (II) by the ligand - donor combination was seen to be between 8 - 9. The effect of different donors like dimethyl sulphoxide (DMSO), trioctyl phosphine oxide (TOPO) and bis(2-ethylhexyl) phosphonate and the effect of various diluents on the extraction of Co(II) by the present method were studied in detail. The binary adduct formation constant (log kex) in the organic phase was found to be 3.182. The overall equilibrium constant (log K) for the ternary species [Co(A)(DMSO)(Cl)], [Co(A)(TOPO)(Cl)] and [Co(A)(phosphonate)(Cl)] were estimated to be 6.42, 6.22 and 6.25 respectively. The trend in equilibrium constants were in accordance with their basic character, i.e., (DMSO > or = TOPO approximately/= phosphonate). The results were extrapolated in the determination of Cobalt in pharmaceutical drugs and cobalt bearing ore samples.

Synergistic extraction of cobalt(II) by tri-octylamine and neutral donors

This work reports a study on the synergistic extraction of cobalt(II), spiked with60Co from hydrochloric acid solutions by mixtures of trioctylamine (TOA) and neutral organophosphorous donors into carbon tetrachloride. Synergistic coefficients and adduct formation constants have been evaluated from distribution measurements and correlated with the basic character of donors.

Thermodynamic Study on the Synergistic Extraction of Cobalt(II) with Acetylacetone and Trioctylphosphine Oxide.

Thermodynamic Study on the Synergistic Extraction of Cobalt(II) with Acetylacetone and Trioctylphosphine Oxide.

Liquid–Liquid Extraction of Cadmium and Cobalt with Mixtures of 1-Phenyl-3-methyl-4-stearoyl-5-hydroxypyrazole (HPMSP) and n-Dodecylamine (DDA) in Toluene

The synergistic extraction of cobalt and cadmium (M 2+) from sulfate and perchlorate media with mixtures of 1-phenyl-3-methyl-4-stearoyl-5-hydroxypyrazole (HPMSP, PMSP − after deprotonation) and n-dodecylamine (DDA, DDAH+ after protonation) has been studied in toluene. In sulfate medium, an easy phase separation is observed. The synergistically extracted species is DDAHċM(PMSP)3, which results from the addition of the predominating DDAHċPMSP ion pair on M(PMSP)2 with logK syn=4.05 (Co) and 4.7 (Cd). In perchlorate medium, in the presence of an excess of DDAHċClO4, which is the predominating DDA species, a stable emulsion appears in the aqueous phase in contact with a clear organic phase. Due to the interfacial character of the extraction process and to aggregation phenomena, a stronger synergistic effect is achieved with Co than with Cd, leading to an increase of the Co/Cd separation coefficient. The synergistic extraction performed from perchlorate medium is slower than that from sulfate medium.

Synergistic extraction of cobalt(II) with oxine/decanoic acid solution mixtures in benzene and chloroform

Synergistic extraction of Co(II) with 8-hydroxyquinoline (Hq)/decanoic acid [(HR)2] solution mixtures in benzene and chloroform was carried out at 25°C. The aqueous ionic strength and the total concentration of cobalt(II) were 0.1 (NaCl) and 1·10−5–1·10−3M, respectively. The synergistic effect is interpreted by the formation of the mixed ligand ion-pair complexes: [(Coq(Hq)2(HR))+, R−] and [(Coq(Hq)2(HR)3)+, R−] in benzene and chloroform, respectively.

Thermodynamic Study on the Synergistic Extraction of Cobalt(II) with .BETA.-Diketones and Trioctylphosphine Oxide.

Thermodynamic Study on the Synergistic Extraction of Cobalt(II) with .BETA.-Diketones and Trioctylphosphine Oxide.

Synergistic extraction of cobalt(II) from cesium containing aqueous solutions with mixtures of 4-acyl-pyrazol-5-ols and crown ethers

The synergistic extraction of cobalt(II) from aqueous solutions loaded with cesium chloride or nitrate, with mixtures of 1-phenyl-3-methyl-4-acyl-pyrazol-5-ols (HL) [acyl = benzoyl (HPMBP), para- tert.-butyl-benzoyl (HPMB′P), stearoyl (HPMSP)] and crown ethers E = B15C5, 18C6, DC18C6, DB18C6 and DB24C8 (DC = dicyclohexano, B = benzo, DB = dibenzo), in CHCl 3, CH 2Cl 2 and ClCH 2CH 2Cl, has been studied. The experimental data agree with the extracted species E 2CsCoL 3 (E = B15C5), ECsCoL 3, (E = DB18C6) and CoL 2E (E = DB24C8). The extraction yields follow the orders: 18C6 ⩾ DC18C6 > DB18C6 > B15C5 > DB24C8, HPMBP > HPMB′P > HPMSP, and ClCH 2CH 2Cl > CH 2Cl 2 > CHCl 3. In spite of the better complexation of potassium than cesium with “18C6” type crown ethers, the extraction of ECsCo (PMBP) 3 is generally higher than the EKCo(PMBP) 3 one. Except in the case of DB24C8, loading the aqueous phase with Cs +, K +, Sr 2+ or Ba 2+ improves the synergistic extraction of cobalt.

Synergistic extraction of cadmium and cobalt with mixtures of 4-stearoyl-pyrazol-5-ol and tri-n-octylamine in toluene

The synergistic extraction of cobalt and cadmium (M2+) from 1M sodium perchlorate medium with mixtures of 1-phenyl-3-methyl-4-stearoyl-pyrazol-5-ol (HPMSP) and tri-n-octylammonium perchlorate (TOAH+, ClO4−) in toluene, at 25°C, has been studied. Co and Cd are extracted asM(PMSP)2 species with HPMSP alone (log12=−7.4 and −9.4 respectively), and as [TOAH−,M(PMSP)3−] species in the presence of (TOAH+, ClO4−). At high (TOAH+, ClO4−) concentrations, the synergistic equilibrium is: $$M^{2 + } + 3\overline {HPMSP} + {\raise0.5ex\hbox{$\scriptstyle 1$}\kern-0.1em/\kern-0.15em\lower0.25ex\hbox{$\scriptstyle 2$}}(\overline {TOAH^ + ,ClO_4 ^ - } )_2 \rightleftharpoons [\overline {TOAH^ + ,M(PMSP)_3 ^ - } ] + 3H^ + + ClO_4 ^ - $$ of constant logK131=−7.10 and −9.45 (M=Co and Cd, respectively). Owing to the anionic exchange between HPMSP and (TOAH+, ClO4−) (logKexc=−4.0) that occurs at highestpH range, the synergistic extraction of cadmium, at low ammonium concentrations, is better described by: $$Cd^{2 + } + 2\overline {HPMSP} + (\overline {TOAH^ + ,PMSP^ - } ) \rightleftharpoons [\overline {TOAH^ + ,Cd(PMSP)_3 ^ - } ] + 2H^ + $$ of constant logK121=−4.65.

Synergistic extraction of cobalt(II) with resacetophenone oxime in the presence of heterocyclic nitrogen and organophosphorous compunds

Equilibrium distribution coefficients have been determined, for the extraction of cobalt(II) with resacetophenone oxime as a function of pH and reagent concentration at ambient temperature. RAPOX forms simple 1∶2 chelate with cobalt(II). Synergistic extraction was observed with pyridine and its methyl derivatives and some organophosphorous compounds. From the extraction equilibrium data, the adduct formation constants of 1∶2 chelate to adducting ligand adducts were evaluated.

ChemInform Abstract: Synergistic Extraction of Cobalt(II) Complexes with Toluene‐3,4‐dithiol in Presence of Some Benzylamines.

The synergistic extraction of cobalt(II) complexes with toluene-3,4-dithiol (TDT) in presence of monobenzylamine (BA), dibenzylamine (DBA) and tribenzylamine (TBA) has been investigated. The stoichiometry of the adducts formed was established from the extraction data. Values of the formation constant,Bex, in presence of the amine ligands have been determined. It is found that the extraction ability decreases in the orderDBA ≫TBA>BA.

Synergistic extraction of cobalt(II) complexes with toluene-3,4-dithiol in presence of some benzylamines

The synergistic extraction of cobalt(II) complexes with toluene-3,4-dithiol (TDT) in presence of monobenzylamine (BA), dibenzylamine (DBA) and tribenzylamine (TBA) has been investigated. The stoichiometry of the adducts formed was established from the extraction data. Values of the formation constant,Bex, in presence of the amine ligands have been determined. It is found that the extraction ability decreases in the orderDBA ≫TBA>BA.

Study on the synergistic extraction of cobalt(II) with lower fatty acids in the presence of heterocyclic amines and some metal ion separations

The synergistic extraction of cobalt(II) with a chloroform solution of propionic, butyric or valeric acid in the presence of β-picoline, pyridine or quinoline has been investigated. The effect of different variables, such as pH of the aqueous phase, and concentration of metal ion, acid and amine, is reported. On the basis of slope analysis the species extracted were generally found to be CoA 2.2HA.2B where HA is the acid and B the base, but CoA 2.HA.2B.H 2O for the butyric acid—quinoline system. The extraction constants were used to assess the relative effectiveness of the amines as synergists. From the extraction data, methods for separation of Co(II) from Mn(II), Cr(III), Fe(III), Zn(II), Cd(II) and Hg(II), with fairly high separation factors, have been worked out.

Synergistic Extraction of Cobalt (II) and Zinc(II) Complexes with 3-Methyl-1-Phenyl-4- Thiobenzoyl-5-Pyrazolone (SBMPP)

Synergistic Extraction of Cobalt (II) and Zinc(II) Complexes with 3-Methyl-1-Phenyl-4- Thiobenzoyl-5-Pyrazolone (SBMPP)