Phosphinic acid solvent extraction

McAlister, D.R., Horwitz, E.P. 2007. Characterization of extraction of chromatographic materials containing bis(2-ethyl-l-hexyl)phosphoric acid, 2-ethyl-1-hexyl (2-ethyl-1-hexyl) phosphonic acid, and bis(2,4,4-trimethyl-l-pentyl)phosphinic acid. Solvent Extraction and Ion Exchange 25(6) 757-769. 

Rickelton, W. A., Flett, D. S. West, D. W. (1984). Cobalt-nickel separation by solvent extraction with bis(2,4,4 trimethylpentyl)phosphinic acid. Solvent Extraction and Ion Exchange, 2, 6,815-838, ISSN 0736-6299 Robertson, A. J. (Cytec Industries) (2001). Phosphonium salts. WO 01/87900 Robertson, A. J. (1983). Process for the preparation of highly purified, dialkyl phosphinic acids. US 4 374 780, WO/2006/047545A2... 

K. Inaba, H. Freiser, and S. Muralidharan, Effect of kinetic factors on the efficiencies of centrifngal partition chromatographic separations of tervalent lanthanides with bis(2,4,4,-trimethylpentyl)phosphinic acid as extractant, Solvent Extract Res. Dev. Japan 1 13 (1994). G. Ma, H. Freiser, and S. Mnralidharan, Centrifugal partition chromatographic separation of tervalent lanthanides using acylpyrazolone extractants, A aZ. Chem. 69 2835 (1997). 

Precipitation of cobalt as sulfide is done in ammoniacal nickel matte leaching. From sulfate or sulfate/chloride solutions, cobalt is nowadays normally removed by using solvent extraction [46]. Phosphine-based solvent extraction reagents such as di-2-ethylhexylphosphoric acid (D2EHPA) are used to extract cobalt from nickel sulfate solutions. From pure chloride electrolytes, solvent extraction is done with a tertiary amine such as tri-isooctylamine. 

The mixture can be separated by distillation. The primary phosphine is recycled for use ia the subsequent autoclave batch, the secondary phosphine is further derivatized to the corresponding phosphinic acid which is widely employed ia the iadustry for the separation of cobalt from nickel by solvent extraction. With even more hindered olefins, such as cyclohexene [110-83-8] the formation of tertiary phosphines is almost nondetectable. 

Solvent Extraction Reagents. Solvent extraction is a solution purification process that is used extensively in the metallurgical and chemical industries. Both inorganic (34,35) and organic (36) solutes are recovered. The large commercial uses of phosphine derivatives in this area involve the separation of cobalt [7440-48-4] from nickel [7440-02-0] and the recovery of acetic acid [61-19-7] and uranium [7440-61-1]. 

In a similar appHcation, Cape Industries has announced its intention to commission a solvent extraction plant to recover acetic acid from an effluent generated at its dimethyl terephthalate [120-61-6] faciHty (Wilmington, North Carolina) (44,45). The plant was commissioned in Eebmary 1995. In this case, the solvent will be CYANEX 923 extractant [100786-00-3], CYANEX 923 is also a phosphine oxide, but unlike TOPO is a Hquid and can be used without a diluent (46,47). This has the benefit of reducing plant size, capital, and operating costs. 

Preston, J. S. Solvent extraction of cobalt and nickel by organophosphorus acids. I. Comparison of phosphoric, phosphonic, and phosphinic acid systems. Hydrometallurgy 1982, 9, 115-133. 

Xun, F. Golding, J. A. Solvent extraction of cobalt and nickel in bis(2,4,4-tri-methylpentyl)phosphinic acid, Cyanex-272. Solvent Extr. Ion Exch. 1987, 5, 205-226. 

Shinde, P. S. Dhadke, P. M. Solvent extraction separation of Cu(II) and Ni(H) with bis(2,4,4-trimethylpentyl)dithio-phosphinic acid (Cyanex 301). Indian J. Chem. Technol. 1996, 3, 367-370. 

The [l-(benzhydrylamino)alkyl]phosphinic acid 32 was heated with an excess of 48% HBr (5 times weight) at 100 °C for 1-2 h until two distinct phases separated. (Note the 48% HBr is pretreated by extraction three times with an equal volume of CH2C12 to remove any bromine, which oxidizes the phosphinic acid.) The mixture was concentrated to dryness under reduced pressure and the residue was taken up in H20. The aqueous soln was washed several times with Et20 to remove DpmBr and concentrated to a thick oil. (Note complete removal of the solvent is important at this point otherwise, residual HBr interferes in the next step.) The oily residue of 1-aminoalkylphosphinic acid hydrobromide was dissolved in EtOH (lOmL-g ) and propylene oxide was added dropwise until precipitation began. The mixture was allowed to stand until precipitation was complete, and the solid 33 was collected by filtration, washed successively with EtOH and Et20, and dried. For Alap analogue mp 223-224 °C 31P NMR (D20, 5) 22.2. 

Fujii, T., Yamana, H., Watanabe, M., Moriyama, H. 2001. Extraction of molybdenum from nitric acid by octyl(phenyl)-N,N-diisobutylcarbamoylmethyl phosphine oxide. Solvent Extr. IonExch. 19 (1) 127-141. 

Cyanex 301 One of the solvent extraction processes, used together with UREX, for separating the components of used nuclear fuel. This process uses a complex phosphinic acid, [bis(2,4,4-trimethylpentyl)dithiophosphinic acid], made by Cytec Industries, Canada. Its purpose is to separate americium, curium, and lanthanide fission products from the other components. 

Amorphous aluminum oxide has recently been proved to extract lithium from brines and bitterns having lithium concentrations of 0.83 and 13.1 mg/1, respectively. The sorption may be explained by the formation of hydrous lithium aluminum oxide. The sorption capacity of amorphous hydrous aluminum oxide was found to be 4.0 mmol/g. For brines and bitterns the lithium concentration factors on the sorbent attained values of 370 and 130, respectively equilibrium was reached after 7 days. The desorption of lithium ions was carried out with boiling water yielding a maximum concentration factor of lithium in the eluate of 46 in reference to the initial lithium concentration of the brines. Lithium was separated from the eluates by solvent extraction with cyclohexane containing thenoyltrifluoracetone and trioctyl-phosphine oxide, subsequent back extraction with hydrochloric acid, and precipitation of lithium phosphate by addition of K3P04. The purity of the precipitate amounted to at least 95% I7 21). 

The formation of this acid has already been described under benzyl-phosphinic acid, p, 115, the white crystalline mass mentioned m that preparation being extracted with potassium hydroxide and precipitated with hydrochloric acid. From hot alcohol it crystallises in shining scales, M.pt. 191° C., readily soluble in hot nitric acid, not very soluble in the usual solvents. It is only a feeble acid, as it does not turn blue htmus red or liberate carbon dioxide from carbonates. The potassium and silver salts are known, the latter reacting with methyl iodide to form the methyl ester, consisting of bushy, silky prisms, M.pt. 75° C. Nitration produces 4 4 -dinitrodibenzylphosphinie acid, forming colourless needles, M.pt. 225° to 226° C. ... 

The recuperation of metal ions is carried out by different types of processes such as solvent extraction [47], membrane separation [48], and chemical absorption [49]. Among these processes, solvent extraction is the most widely adopted type for the removal of metals, where the extraction agent (such as di(2-ethylhexyl) phosphoric acid, trw(2-ethylhexyl)amine, liquid phosphine oxides) is dissolved in an organic solvent (kerosene, toluene, etc.) that is used as the diluents [50,51]. 

Solvent extraction of acetic acid from dilute aqueous industrial streams by commercial organic bases(such as various amines(Amberlite s.Adogen s.Alamine s etc.) and tri-octyl phosphine oxide(TOPO) )... 

The technology for the commerdal plants is based c i solvent extraction althoi h other methods have been developed. Much of the development work on solvent extraction was done by the U.S. Government-owned Oak Ridge National Laboratory (ORNL) in Tennessee 134,351. Most of the processes use either octyl pyro-pho horic acid solvent (OPP/, as in the earliest processes in the United States, or various combinations of solvents, developed later by ORNL, di(2-ethylheksyl) phosphoric acid (DEPA), trioctyl phosphine oxide (TOPO), and oct phenylphosphoric add (OPAP). 

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