Transportation of Zinc(II) in Bulk Liquid Membranes Containing Phosphonium Ionic Liquid (original) (raw)
Related papers
Selective transport of zinc and copper ions by synthetic ionophores using liquid membrane technology
Journal of Inclusion Phenomena and Macrocyclic Chemistry, 2012
This work highlights the role of synthetic carrier (ionophore) in the separation of heavy metal ions. A new series of ionophores; 4,4 0-nitrophenyl-azo-O,O 0-phenyl-3,6, 9-trioxaundecane-1,10-dioate (R 1), bis[4,4 0 nitro-phenylazonaphthyl-(2,2-dioxydiethylether)] (R 2) 1,8-bis-(2-naphthyloxy)-3,6-dioxaoctane (R 3), 1,11-bis-(2-naphthyloxy)-3,6,9trioxaunde-cane (R 4), 1,5-bis-(2-naphthyloxy)-3-oxa-pentane (R 5) have been synthesized and used as extractant as well as carrier for the transport of various metal ions (Na ? , K ? , Mg 2? , Ni 2? , Cu 2? and Zn 2?) through liquid membranes. Effect of various parameters such as metal ion concentration, ionophore concentration, liquid-liquid extraction, back extraction, comparison of transport efficiency of BLM and SLM and different membrane support (hen's egg shell and PTFE) have been studied. In BLM ionophores (R 2-R 5) transport Zn ? at greater extent and the observed trend for the transport of Zn 2? is R 2 [ R 4 [ R 3 [ R 5 respectively. Further transport efficiency is increased in SLM. In egg shell membrane ionophores (R 2-R 5) transport Zn ? due to their non-cyclic structure and pseudo cavity formation while ionophore R 1 transports Cu 2? ions at greater extent due to its cyclic structure and cavity size. Among the membrane support used egg shell membrane is found best for the transport of zinc ions because of its hydrophobic nature and exhibits electrostatic interactions between positively charged zinc ions and-COOH group of egg shell membrane. Thus structure of ionophores, hydrophobicity and porosity of the membrane support plays important role in separation of metal ions.
Separation and Purification Technology, 2009
Trihexyl(tetradecyl)phosphonium chloride (Cyphos ® IL 101) and bis(trifluoromethylsulphonyl)imide (Cyphos ® IL 109) -phosphonium ionic liquids -were used as novel reagents mixed with toluene to extract zinc(II) from chloride media. Extraction of zinc(II) was very fast and efficient (E Zn over 95%) for molar ratio of Cyphos ® IL 101/Zn(II) more than 2. It was found that the presence of HCl in the feed enhanced Zn(II) extraction. The reactions of Zn(II) extraction mechanism were proposed. The values of H • were estimated to be 32.93 (standard deviation (s.d.) = 2.81) and 52.85 (s.d. = 1.90) kJ mol −1 and S • amounted to 120.65 (s.d. = 8.84) and 182.13 (s.d. = 6.02) J mol −1 K −1 for reaction without HCl and with 0.58 M acid, respectively. The extraction of zinc(II) with Cyphos ® IL 101/toluene mixture is an endothermic reaction. Successful stripping of zinc(II) from the loaded organic phase was achieved with 1 M sulphuric acid. Cyphos ® IL 101 can be reused at least in 3 cycles of extraction-stripping process. Due to low extraction of Zn(II) Cyphos ® IL 109 cannot be considered as effective extractant in the studied system.
Hydrometallurgy, 2011
Trihexyl(tetradecyl)phosphonium chloride (Cyphos IL 101)a phosphonium ionic liquidwas used as a novel reagent mixed with toluene to extract selectively zinc(II) from chloride media in the presence of iron(II). The extraction of individual metal ions with Cyphos IL 101 increases in the following order: iron(II)b zinc(II) b iron(III). Zinc(II) extraction is preferred over iron(II) when both are present in the feed. Maximum loading capacity of 50 vol.% Cyphos IL 101 amounts to 45, 40 and almost 30 g dm − 3 of Fe(III), Zn(II) and Fe(II), respectively. Selective separation of Zn(II) from mixtures of Zn(II) and Fe(II) model spent pickling solutions is investigated in multistage extraction-stripping. Zn(II) extraction from the feed containing only 5 g dm − 3 exceeds 85% after the first extraction stage, reaching almost 100% after three stages. Meanwhile, iron(II) extraction also increases (after three stages it amounts to 40%). Extraction in the presence of 120 g dm − 3 Zn(II) and 35 g dm − 3 Fe(II) needs four extraction stages to deplete Zn(II) in the feed. At the same time Fe(II) extraction is low and equals less than 20% after four stages. Stripping of the predominant metal ions takes place prior to the deficient ones. Zinc(II) can be selectively transferred from the feed containing high Zn(II) concentration and four times lower concentration of Fe(II) to the stripping phase. The most important from the practical point of view is the ability of Cyphos IL 101/toluene mixture to separate selectively zinc(II) from iron(II) when both are in concentrated zinc(II) feeds.
This paper presents an application of three phosphonium ionic liquids for removal of Pd(II) ions from aqueous chloride solutions with liquid-liquid extraction and transport across polymer inclusion membranes (PIM). Trihexyl(tetradecyl)phosphonium chloride and bromide (Cyphos IL 101 and 102) and bis-(2,4,4-trimethylpentyl)phosphinate (Cyphos IL 104) were investigated as carriers of Pd(II) from aqueous chloride media. Extraction of Pd(II) with Cyphos IL 102 has not been previously described in the literature. Cyphos IL 102 used for the first time as metal ion carrier, efficiently extracts palladium(II) ions both with liquid-liquid extraction and PIM. NaCl concentration does not affect Pd(II) extraction with Cyphos IL 102, while increasing HCl content in the feed aqueous phase causes decrease in extraction efficiency. Stripping of Pd(II) with 0.5 M NH 4 OH is efficient (84 to 90%) and the organic phase after stripping could be reused for extraction. For PIM transport the highest values...
Separation of copper and zinc by supported liquid membrane using TOPS99 as mobile carrier
Hydrometallurgy, 2004
The separation of copper and zinc from an aqueous sulphate media by supported liquid membrane (SLM) using di-2-ethyl hexyl phosphoric acid (TOPS-99) as mobile carrier has been studied. Celgard-2500, a microporous polypropylene film, was used as the solid support for the liquid membrane. A plate and frame type of cell was used for the experiment. The effects of different parameters such as flow rate, pH of feed solution, TOPS-99 concentration in the membrane phase and acid concentration in strip solution on separation of copper and zinc were studied. It was observed that flow rate of 100 mL/min (velocity 85.7 m/h) was sufficient to reduce the resistances due to the aqueous boundary layer. Zinc was permeated in a pH region 1.5 -5.0, while copper permeation started at pH 3.0. At pH 2.5, the co-permeation of copper with zinc was negligible, and a high separation factor was achieved at this pH. D
Talanta, 2009
A polymer inclusion membrane (PIM) is reported consisting of 45% (m/m) di(2-ethylhexyl)phosphoric acid (D2EHPA) immobilized in poly(vinyl chloride) (PVC) for use as a solid phase absorbent for selectively extracting Zn(II) from aqueous solutions in the presence of Cd(II), Co(II), Cu(II), Ni(II) and Fe(II). Interference from Fe(III) in the sample is eliminated by precipitation with orthophosphate prior to the extraction of Zn(II). Studies using a dual compartment transport cell have shown that the Zn(II) flux (2.58 x 10(-6)mol m(-2)s(-1)) is comparable to that observed for supported liquid membranes. The stoichiometry of the extracted complex is shown to be ZnR(2).HR, where R is the D2EHPA anion.
Chemical Engineering & Technology, 2008
The separation of zinc and copper ions from sulfuric acid solutions by an emulsion liquid membrane (ELM), using di-(2-ethylhexyl) phosphoric acid (D2EHPA) as a carrier, has been investigated. The batch extraction of zinc and copper was carried out while varying a selection of experimental conditions, i.e., stirring speed, treatment ratio, concentrations of metal ions in the feed phase, carrier and Span 80 concentration in the membrane, and internal phase concentration. The results obtained demonstrate the effectiveness of D2EHPA as a carrier for the separation of zinc and copper from sulfuric acid media using an ELM. An increase of the D2EHPA concentration beyond 2 vol.-% does not result in the improved extraction of zinc because the viscosities of the membrane and emulsion have a trend to increase for higher carrier concentrations. It was found that the extraction rate of copper was affected by the carrier concentration in the liquid membrane and by the pH and metal content in the external phase. A 3 vol.-% concentration of surfactant in the organic phase was required to stabilize the emulsion. The number of stages required for the extraction of zinc and copper by an ELM was determined from McCabe-Thiele plots.
Reviews in Chemical Engineering, 2015
This paper analyzes the applications of various ionic liquids (ILs) as metal ion carriers and extractants utilized for the separation of metal cations from aqueous solutions. Subsequently, an up-to-date review of the use of ILs in polymer inclusion membranes is presented. ILs represent a promising group of extractants and ion carriers of metal ions in extraction and membrane separation processes. The removal of heavy metals ions from aqueous solutions using ILs indicates an extensive and promising research area. It is expected that the role of ILs will gradually increase as the worldwide implementation of separation methods in recovery of metal ions from various aqueous solutions is growing quickly.
Removal of Zn(II) from chloride acidic solutions with hydrophobic quaternary salts
Polish Journal of Chemical Technology, 2010
The equilibrium of zinc(II) extraction from hydrochloric acid solutions with phosphonium and ammonium quaternary salts and their application as carriers in polymer inclusion membranes were studied. The most efficient was the extraction of zinc with the use of chlorides and bromide of ammonium and phosphonium salt (more than 90%). Quaternary ammonium and phosphonium chlorides and bromide are efficient extractants of zinc(II) from hydrochloric acid solutions. Two-fold molar excess of extractant over Zn(II) is necessary for efficient extraction (100%). Solvent extraction power of the extractants studied decreases with increasing hydrophobicity of the anion in the following sequence: QPCl > QPBr > QPBis > QACl > QABF 4 > QPBF 4 > QPPF 6 > QPNtf 2 . A solution of 1 M H 2 SO 4 is chosen as the best stripping phase from the technological and economical point of view. Transport across polymeric inclusion membrane enables concentration of the stripping solution; however it takes a very long time.