scholarly journals Effect of the Addition of Amine in Organophosphorus Compounds on Molecular Structuration of Ionic Liquids–Application to Solvent Extraction

Molecules ◽  
2020 ◽  
Vol 25 (11) ◽  
pp. 2584 ◽  
Author(s):  
Soumaya Gmar ◽  
Fabrice Mutelet ◽  
Alexandre Chagnes

Variation of dynamic viscosity, density and enthalpy as a function of mole fraction of amine (tri-n-octylamine, triisooctylamine, bis(2-ethylhexyl)amine) in bis(2-ethylhexyl) phosphoric acid (D2EHPA) or Cyanex 272, (bis(2,4,4-trimethylpentyl)phosphinic acid) has been determined at 25 °C. Valuable information regarding structuration and destabilization of the corresponding ionic liquids has been deduced from these data. A simple model describing the variation of dynamic viscosity as a function of mole fraction of amine has been used to determine the speciation in these mixtures. Extraction tests of cobalt(II) and nickel(II) by D2EHPA-amine mixtures have shown the highest cobalt(II)-nickel(II) selectivity has been achieved with D2EHPA-2-ethylhexylamine mixture as cobalt(II) extraction efficiency of 77% was obtained, while no significant nickel(II) extraction was observed at a chloride concentration of 3 mol·L−1.

Molecules ◽  
2020 ◽  
Vol 25 (18) ◽  
pp. 4236
Author(s):  
Agnieszka Głowińska ◽  
Andrzej W. Trochimczuk

Efficient separation technologies are crucial to the environment and world economy. The challenge posed to scientists is how to engineer selectivity towards a targeted substrate, especially from multicomponent solutions. Polymer-supported reagents have gained a lot of attention in this context, as they eliminate a lot of inconveniences concerning widely used solvent extraction techniques. Nevertheless, the choice of an appropriate ligand for immobilization may be derived from the behavior of soluble compounds under solvent extraction conditions. Organophosphorus compounds play a significant role in separation science and technology. The features they possess, such as variable oxidation states, multivalence, asymmetry and metal-binding properties, highlight their status as a unique and versatile class of compounds, capable of selective separations proceeding through different mechanisms. This review provides a detailed survey of polymers containing phosphoric, phosphonic and phosphinic acid functionalities in the side chain and covers main advances in the preparation and application of these materials in separation science, including the most relevant synthesis routes (Arbuzov, Perkow, Mannich, Kabachnik-Fields reactions, etc.), as well as the main stages in the development of organophosphorus resins and the most important achievements in the field.


2007 ◽  
Vol 62 (5-6) ◽  
pp. 281-291 ◽  
Author(s):  
Huimin Luo ◽  
Miao Yu ◽  
Sheng Dai

A series of new hydrophobic and protic alkylammonium ionic liquids with bis(trifluoromethylsulfonyl) imide or bis(perfluoroethylsulfonyl)imide as conjugated anions was synthesized in a one-pot reaction with a high yield. In essence our synthesis method involves the combination of neutralization and metathesis reactions. Some of these hydrophobic and protic ionic liquids were liquids at room temperature and therefore investigated as new extraction media for separation of Sr2+ and Cs+ from aqueous solutions. An excellent extraction efficiency was found for some of these ionic liquids using dicyclohexano-18-crown-6 and calix[4]arene-bis(tert-octylbenzo-crown-6) as extractants. The observed enhancement in the extraction efficiency can be attributed to the greater hydrophilicity of the cations of the protic ionic liquids. The application of the protic ionic liquids as new solvent systems for solvent extraction opens up a new avenue in searching for simple and efficient ionic liquids for tailored separation processes.


2017 ◽  
Vol 82 (5) ◽  
pp. 579-592 ◽  
Author(s):  
Xing Li ◽  
Jun Li ◽  
Yang Jin ◽  
Ming Chen ◽  
Dongya Feng ◽  
...  

Solvent extraction is an efficient, economical and widely-used technology for the purification of wet process phosphoric acid (WPA). This present work focused on the development of a solvent extraction system, TC, representing tri-n-butyl phosphate (TBP) and cyclohexanol mixtures. The equilibrium phase diagram of the system H3PO4?H2O?TC at 298.2 K and atmospheric pressure was obtained. The effects of extraction time, phosphoric acid concentration, extractant concentration, temperature and phase volume ratio on extraction efficiency were studied. The extracted complexes were estimated to be 1.8H3PO4 2TC. The extraction process of H3PO4 was exothermic and the enthalpy change, ?H, was obtained. The solvent mixtures had a high efficiency for phosphoric acid purification via multi-stage counter-current extraction from the industrial WPA in a reciprocating plate extraction column with an H3PO4 extraction yield of 85.08 % at 313.2 K. The stability, extraction efficiency and recycling capability of TC for H3PO4 extraction were also estimated.


2020 ◽  
Vol 10 (1) ◽  
pp. 001-010 ◽  
Author(s):  
Nikoletta Harsági ◽  
Betti Szőllősi ◽  
Nóra Zsuzsa Kiss ◽  
György Keglevich

Abstract The optimized HCl-catalyzed hydrolysis of alkyl diphenylphosphinates is described. The reaction times and pseudo-first-order rate constants suggested the iPr > Me > Et ∼ Pr ∼ Bu order of reactivity in respect of the alkyl group of the phosphinates. The MW-assisted p-toluenesulfonic acid (PTSA)-catalyzed variation means a better alternative possibility due to the shorter reaction times, and the alkaline hydrolysis is another option. The transesterification of alkyl diphenylphosphinates took place only in the presence of suitable ionic liquids, such as butyl-methylimidazolium hexafluorophosphorate ([bmim][PF6]) and butyl-methylimidazolium tetrafluoroborate ([bmim][BF4]). The application of ethyl-methylimidazolium hydrosulfate ([emim][HSO4]) and butyl-methylimidazolium chloride ([bmim][Cl]) was not too efficient, as the formation of the ester was accompanied by the fission of the O–C bond resulting in the formation of Ph2P(O)OH. This surprising transformation may be utilized in the phosphinate → phosphinic acid conversion.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Rajesh B. Gujar ◽  
Parveen K. Verma ◽  
Prasanta K. Mohapatra ◽  
Mudassir Iqbal ◽  
Jurriaan Huskens ◽  
...  

Abstract Neptunium is one of the most important minor actinide elements with some of its isotopes having very long half-lives, therefore necessitating its separation from acidic radioactive wastes. Solvent extraction of Np4+ and NpO2 2+ was studied using three multiple diglycolamide (DGA) extractants with n-propyl, n-octyl and 3-pentyl substituents termed as L I , L II and L III , respectively, in a mixed diluent of 5% isodecanol and 95% n-dodecane. For comparison purpose, the extraction of Pu4+ and UO2 2+ was carried out under identical conditions. The extraction efficiency of the ligands for the tetravalent ions followed the trend: L II  > L I  > L III , which changed to L III  > L II  > L I for the hexavalent ions. While the extraction of the tetravalent ions was reasonably good (ca. 90–98%) with an extremely low (5.0 × 10−5 M) ligand concentration, poor extraction (ca. 5–16%) of the hexavalent ions was seen even with a 20 times higher concentration of the ligand. In general, Pu4+ was better extracted than Np4+, while NpO2 2+ was marginally better extracted then UO2 2+. A ‘solvation’ type extraction mechanism was proposed based on the extraction profiles obtained as a function of the concentrations of the feed nitric acid, extractant as well as nitrate ion. The extracted species were found out to be M(NO3)4·mL and MO2(NO3)2·nL (M = Np or Pu, 1 < m < 2, n ≃ 1).


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