Extractants high-molecular-weight amines

Anionic extractants are commonly based on high molecular weight amines. Metal anions such as MnO or ReO can be exchanged selectively with inorganic anions such as Cl or The equiHbrium for a quaternary onium compound of organic radicals R for two anion species A and B ... 

Chelating extractants owe effectiveness to the attraction of adjacent groups on the molecule for the metal. Anionic extractants are commonly based tin high molecular weight amines. Solvating extractants contain one or more electron donor atoms, usually oxygen, which can supplant or partially supplant the water W hich is altached to the metal ions. 

Tungsten Sodium tungstate solution at pH 2 High-molecular weight amine extractant in kerosene mixer-settler system... 

Vanadium Raffinates from uranium ore extraction process Mineral leach liquors D2EHPA and TBP in kerosene High-molecular weight amines in kerosene... 

Moor , F. L., "Liquid-Liquid Extraction with High-Molecular Weight Amine," Nuclear Science Series Report, NAS-NS-3101 (I960). 

Alkyl ammonium compounds. High-molecular-weight amines are very useful actinide extractants in both analytical and process applications. Salts of primary, secondary, and tertiary amines, as well as quaternary ammonium bases RNH2, R2NH, R3N, and R N, are commonly used. These compounds, which are often thought of as anion exchangers, may also be considered as neutral-species coordinators since equivalent equilibrium expressions can be written based on either mechanism. That is,... 

High molecular-weight amines are of particular importance in the extraction [35-39]. They form ion-associates with acids (e.g., HSCN, HReOa, HI), metal-complex acids [e.g., H2PtCl6, HFeCU, H2U02(S04)2]2, and heteropoly acids. These complexes are extractable into non-polar solvents (e.g., CeHa, CHCI3, CCI4) and polar solvents (e.g., MIBK, amyl alcohol). Tertiary amines, such as tribenzylamine (TBA) and tri-n-octylamine (TOA) are most commonly used. Tertiary and secondary amines are used for extraction of anions from acid solutions, whereas quaternary ammonium salts enable also extraction from neutral and alkaline solutions. Secondary and tertiary amines and quaternary ammonium salts are applied as solutions in non-polar solvents. Diphenylguanidine (formula 1.13) is also frequently used in extraction. 

Antipyrine and its derivatives [42,43] such as diantipyrylmethane (DAM, formula 1.8) are high molecular-weight amine extractants. In acid solutions, diantipyrylmethane is protonated, and the resulting cation combines with an anion to form an ion-associate (e.g., DAM H -][TlBr4 ], [DAM H ]2[CdL, ]. 

As(V) has been separated from a number of elements by extraction into butanol from acidic medium as the molybdoarsenic heteropoly acid [11]. This acid has been extracted with solutions of some high molecular-weight amines in 1,2-dichloroethane [12]. 

Extraction of the cadmium-iodide complex from iodide-H2S04 solutions with oxygen-containing solvents (e.g., mesityl oxide, 2-ethyl-1-butanol) is a selective recommended separation method (e.g., from zinc) [1-3]. The iodide complex of cadmium can also be extracted with high molecular weight amines in xylene [4], TBP in benzene [5], and with tetra-n-butylammonium iodide in CHCI3 [6]. 

Inert solvents (e.g., CHCI3, CeH, 1,2-dichloroethane) extract ion-associates of chromate with high molecular-weight amines, e.g., TOA [4], tribenzylamine [5], and 4-(5-nonyl)pyridine [6], from acid media (HCl, H2SO4, HCIO4, HNO3). TOPO in benzene and a tetraphenylarsonium salt in CHCI3 have also been used [1]. 

Higher sensitivity is obtained by extracting the anionic Pt complex with chloroform or benzene in the presence of TO A or another long-chain high molecular-weight amine [9]. Platinum has been extracted with TOA before the determination in gold [38]. 

Rare-earth elements can be separated from other metals by extraction methods using the complexes with TOPO (MIBK) [19], HTTA with TOPO (toluene) [20,21], HDEHP [22-24], DDTC [25], 8-hydroxyquinoline with phen [26] or with tetra-n-heptylammonium ion (CHCI3) [27], high molecular-weight amine [28], EDTA in the presence of Capriquat [29], a-diketones [30], and 2-thenoyltrifluoroacetone [31-34]. 

The selectivity of the method can be increased by prior separation of the zinc, e.g., by its extraction (with benzene or xylene) as the chloride complex in the presence of high molecular-weight amines [44],... 

The application of high molecular weight amines, trioctylamine (1,2-dichloroethane) [4], N-octylaniline (xylene) [5,6], diantipyrylmethane [4,7] and Cyanex 302 (toluene) [8] to separation of the elements has recently been reported. Extraction of ion pairs of anionic complexes of the analytes with the other counter ions, e.g. tiiphenylarsine oxide [9] or various dyes, e.g. Rhodamine B [10] and polymethine dyes [11], has recently been investigated. 

SPILL CLEAN-UP use water spray to "knock down" dust use solvent extraction with high molecular-weight amines and quaternary ammonium compounds for the removal or arsenic from industrial effluents. 

High molecular weight amines are basic extractants sometimes called liquid anion exchangers. They have been used for anionic metal complexes. Examples include tetraphenylborate (TPB), trioctylamine (TOA), triisooctylamine (TIOA), and trilaurylamine (TLA). 

The use of chelating reagents (LIX and Kelex series), which are commercially available for solvent extraction, has been reviewed by Ashbrook 490). High-molecular-weight amines (Aliquat, Alamine, and Adogen series) are also in commercial use. The use of Aliquat-336 in the extraction of thorium 491) from spring waters has recently been reported 492). 

Detection and Measurement of Nuclear Radiation, NAS-NS-3105, 1.50 Liquid-liquid Extraction with High-molecular-weight Amines, NAS-NS-3101, 1.00... 

Sato, T. Takayanagi, T. Sato, K. (2010). Liquid-Liquid Extraction of Palladium(II) from Hydrochloric Acid Solutions by High Molecular Weight Amines. Solvent Extr. Res. Dev., Japan, Vol.l7, pp. 95-110... 

Cation-Exchange Techniques In Radio-chemistry. N AS-NS 113 [ 19711, 7.50 Chemical Yield Determinations In Radio-chemistry, NAS-NS-3111 [1967], 5.50 Detection and Measurement of Nuclear Radiation, NAS-NS-3105 [1961], 6.00 Liquid-Liquid Extraction with High-Molecular-Weight Amines, NAS-NS-3101... 

High molecular weight primary, secondary, and tertiary amines can be employed as extractants for zirconium and hafnium in hydrochloric acid (49—51). With similar aqueous-phase conditions, the selectivity is in the order tertiary > secondary > primary amines. The addition of small amounts of nitric acid increases the separation of zirconium and hafnium but decreases the zirconium yield. Good extraction of zirconium and hafnium from ca 1 Af sulfuric acid has been effected with tertiary amines (52—54), with separation factors of 10 or more. A system of this type, using trioctylarnine in kerosene as the organic solvent, is used by Nippon Mining of Japan in the production of zirconium (55). 

Extraction by proton transfer or by ion-pair formation using high molecular weight aliphatic amines... 

In many non-phosphate samples, uranium can be coprecipitated with magnesium hydroxide or otherwise concentrated and extracted from a sulfate system into an extractive scintillator containing a high-molecular-weight tertiary amine sulfate. 

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