Studies on the Separation and Recovery of Thorium from Nitric Acid Medium using (2-ethyl hexyl) Phosphonic Acid,Mono (2-ethyl hexyl) Ester (PC88A)/N-Dodecane as Extractant System

This paper deals with the studies on the separation and recovery of thorium and 233-uranium from nitric acid medium using (2-ethyl hexyl) phosphonic acid, mono (2-ethyl hexyl) ester/n-dodecane as an extractant system. The different extraction parameters were investigated. The distribution ratio of thorium decreased with increase in nitric acid concentration. The optimum solvent concentration for quantitative separation of thorium from aqueous feed solution was 0.75 M of PC88A whereas dodecane was the most suitable of diluents with an organic to aqueous phase ratio of 1:1. Among the various strippants used, 2 M solution of (NH₄)₂CO₃ was found to be the most suitable for back extraction of thorium. The developed method was used to recover thorium and ²³³U from radioanalytical waste generated during thorium analysis by ethylene diamine tetraacetic acid (EDTA) titremtric method and recoveries for both Th and U were more than 85%.     

Studies on the Recovery of Uranium from Phosphoric Acid Medium Using Synergistic Mixture of 2-Ethyl Hexyl Hydrogen 2-Ethyl Hexyl Phosphonate and Octyl(phenyl)-N,N-diisobutyl Carbamoyl Methyl Phosphine Oxide

Abstract

This paper describes the extraction of uranium from aqueous phosphoric acid medium using 2-ethyl hexyl hydrogen 2-ethyl hexyl phosphonate (PC88A) and octyl (phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) individually as well as their synergistic mixture in different diluents. The extraction parameters such as variation in concentration of either of the extractants, concentration of H₃PO₄ and uranium in the aqueous phase are investigated to optimize the extraction conditions. Results indicate that the synergistic mixture, 0.9 M PC88A + 0.1 M CMPO in xylene, can be used for the extraction of uranium from the phosphoric acid medium. The loaded uranium from the synergistic organic phase can be stripped using 0.5 M solution of (NH₄)₂CO₃. This synergistic mixture is used to recover uranium from a typical wet process phosphoric acid sample and the recovery is found to be better than 90%.     

Transport of Thorium(IV) Across a Supported Liquid Membrane Containing N,N,N′,N′-Tetraoctyl-3-oxapentanediamide (TODGA) as the Extractant

The transport behavior of Th⁴⁺ was investigated from a feed containing 3.0 M HNO₃ into a receiver phase containing 0.1 M oxalic acid across a PTFE flat sheet supported liquid membrane (SLM) which contained TODGA (N,N,N′,N′-Tetraoctyl-3-oxapentanediamide) in n-dodecane as the extractant. Effects of the nature of the strippant, extractant concentration, Th concentration in the feed, and feed acidity on the transport rates were investigated. The transport behavior apparently depended on the rate of extraction of the metal ion at the feed-membrane interface and was not diffusion controlled. Influence of Th concentration on flux was also investigated. Transport mechanism was elucidated and the diffusion coefficient was calculated to be 2.13 × 10^?7 cm²/s. Solvent extraction studies at varying feed acidity and TODGA concentration were also carried out.     

Separation of Carrier Free 90Y from 90Sr by Hollow Fiber Supported Liquid Membrane Containing Bis(2-ethylhexyl) Phosphonic Acid

The present article gives a comparative account of the efficiency of carrier-free ⁹⁰Y separation from ⁹⁰Sr by solvent extraction, flat sheet-supported liquid membrane (FSSLM) and hollow fiber-supported liquid membrane (HFSLM) methods using bis(2-ethylhexyl) phosphonic acid (PC88A) as the carrier extractant. The major focus of this work has been to develop the HFSLM method for the separation of Y(III) on a relatively large scale. The feed and receiver phase conditions were optimized by carrying out batch solvent-extraction studies. The extraction of Sr(II) by PC88A was negligible in the acidity range of 0.01–3 M HNO₃, whereas the extraction of Y(III) was significantly large at lower acidity (≤0.1 M HNO₃) with a separation factor (SF = D_Y/D_Sr) of 8.5 × 10⁴. HFSLM studies suggested selective and efficient transport of Y(III) into 3 M HNO₃ from a feed solution containing a mixture of Y(III) and Sr(II) at 0.1 M HNO₃. On the other hand, transport of Sr(II) was negligible in the receiver phase. The purity of the separated ⁹⁰Y was ascertained by paper chromatography and by half-life measurement. The radiation stability of the carrier was excellent as studied up to 1000 KGy dose.     

Studies on the Recovery of Uranium from Phosphoric Acid Medium by D2EHPA/n-Dodecane Supported Liquid Membrane

Abstract

Present studies deal with the application of supported liquid membrane (SLM) technique for the separation of uranium (VI) from phosphoric acid medium using Di-2 ethyl hexyl phosphoric acid (D2EHPA)/n-dodecane as a carrier and ammonium carbonate as a receiving phase. The studies involve the investigation of process controlling parameters like feed acidity of phosphoric acid, carrier concentration, stripping agents, and the effect of thickness and the pore size of the membrane. The transport of uranium decreases with increase in the concentration of phosphoric acid in feed solution whereas it increases with increase in carrier concentration in supported liquid membrane. More than 90% uranium (VI) is recovered in 360 minutes using 0.5 M D2EHPA/dodecane as carrier and 0.5 M ammonium carbonate as stripping phase from the 0.001 M H₃PO₄ feed. Lower concentration of phosphoric acid and higher carrier concentration is found to be the most suitable condition for maximum transport of uranium (VI) from its lean sources like commercial phosphoric acid and analytical wastes generated from the analysis of uranium by Volumetric (Davis-Gray) method.     

Uranium Permeation Studies from Nitric Acid Medium across Supported Liquid Membrane Impregnated with PC88A and its Mixtures with Neutral Oxodonors in n-paraffin as Carriers

The permeation of U(VI) from nitric acid medium using supported liquid membrane (SLM) technique has been studied employing varying compositions of feed (uranium concentration and acidity), carrier, and receiving phase. Microporous polytetrafluoroethylene (PTFE) membranes were used as a solid support and 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester (PC88A) either alone or as a mixture of neutral donors like tri-n-butyl phosphate (TBP), tris(2-ethylhexyl) phosphate (TEHP), and tri-n-octyl phosphine oxide (TOPO) dissolved in n-parrafin as the carrier. Oxalic acid/Na₂CO₃ solutions were used as the receiving phase. The permeability coefficient (P) of U(VI) decreased with increased nitric acid concentration up to 3 M HNO₃ and thereafter increased up to 5 M HNO₃. Uranium permeation was also investigated from its binary mixtures with other metal ions such as Zr(IV), Th(IV), and Y(III) at 2 M HNO₃ employing 0.1 M PC88A/n-paraffin as the carrier, and 0.5 M oxalic acid as the receiver phase. The presence of neutral donors in the carrier solution enhanced the permeation of U(VI) across the SLM in the following order: TEHP ～ TBP > TOPO using 0.1 M oxalic acid as receiver phase. There was significant enhancement in uranium transport for feed acidity ≤2 M HNO₃ employing 1 M Na₂CO₃ as the receiver phase. These studies suggested that 0.1 M PC88A and 0.5 M oxalic acid as carrier and receiver phases appear suitable for selective and faster transport of uranium from the uranyl nitrate raffinate (UNR) waste solutions.     

Studies on permeation of uranium (VI) from phosphoric acid medium through supported liquid membrane comprising a binary mixture of PC88A and Cyanex 923 in n-dodecane as carrier

Present studies deal with the application of supported liquid membrane (SLM) technique for the separation of uranium (VI) from phosphoric acid medium using a binary mixture of 2-ethyl hexyl phosphoric acid-mono-2-ethyl hexyl ester (PC88A) and neutral donor which is a mixture of four tri-alkyl phosphine oxide better known as Cyanex 923 in n-dodecane as a carrier and (NH₄)₂CO₃ as a receiving phase. Various parameters like feed acidity, nature of strippant, carrier concentration, membrane pore size, membrane thickness etc. which affect the transport of U(VI) have been studied in detail. Experiments have also been carried out to see the transport behaviour of different fission products from a diluted High Level Waste (HLW) solution. Stability of the membrane against the leaching of the extractant and stability of the membrane support have also been investigated. We have tried to model the physicochemical transport of U(VI) in SLM as well as establishing the mechanism (Diffusion controlled) of transport. More than 95% uranium (VI) is recovered in 360 min using a binary mixture of 0.60 M PC88A and 0.15 M Cyanex 923 in n-dodecane as carrier and 0.5 M (NH₄)₂CO₃ as stripping phase from the 0.5 M H₃PO₄ feed. Lower concentration of H₃PO₄ (0.5 M) and optimum carrier concentration (0.60 M PC88A + 0.15 M Cyanex 923) in the mole ratio of 4:1 is found to be the most suitable condition for maximum transport of uranium (VI). The optimum conditions obtained from this study was also applied to recover uranium from analytical waste in phosphoric acid medium generated in the laboratory.     

Carrier Facilitated Transport of Europium(III) Across Supported Liquid Membranes Containing N,N,N′,N′-tetra-2-ethylhexyl-3-oxapentane-diamide (T2EHDGA) as the Extractant

Studies on the solvent extraction and pertraction behavior of europium(III) was carried out from acidic feed solutions using N,N,N′,N′-tetra-2-ethylhexyl-3-oxapentane-diamide (T2EHDGA) in n-dodecane as the solvent. The nature of the extracted species from the solvent extraction studies conformed to Eu(NO₃)₃ · 3T2EHDGA which is in variance with the analogous Eu(III) – TODGA (linear homolog of T2EHDGA) extraction system. The transport behavior of Eu(III) was investigated from a feed containing 3.0 M HNO₃ into a receiver phase containing 0.01 M HNO₃ across a PTFE flat sheet supported liquid membrane (SLM) containing 0.2 M T2EHDGA in n-dodecane as the carrier solvent and 30% iso-decanol as the phase modifier. Effects of feed acidity, carrier extractant concentration, membrane pore size, and Eu concentration in the feed on the transport rates of Eu(III) were also investigated. Membrane diffusion coefficient (D _o) for the pertracted species was calculated using the Wilke-Chang equation as 4.25 × 10^?6 cm² · s^?1. The influence of Eu concentration on the flux was also investigated. The role of temperature on the transport rates was investigated and the thermodynamic parameters were calculated.     

DISTRIBUTION BEHAVIOUR OF U(VI), Th(IV) AND Pa(V) FROM NITRIC ACID MEDIUM USING LINEAR AND BRANCHED CHAIN EXTRACTANTS

ABSTRACT

The extraction behaviour of 1M solutions of tri-2-ethylhexyl phosphate (TEHP), di-2-ethyl hexyl isobutyramide (D2EHIBA), tri-n-butyl phosphate (TBP) and di-n-hexyl hexanamide (DHHA) in n-dodecane towards U(VI), Th(IV) and Pa(V) in the presence of 220 g/L of Th from nitric acid medium has been studied. The limiting organic concentrations (LOC) of thorium (g/L) for 1 M TBP and 1 M DHHA are evaluated as 31, 20 ( at 1 M HNO₃) and 25,13 (at 4 M HNO₃) respectively. The distribution ratio (D) values of U(VI), Th(IV) and Pa(V) in the presence of thorium (220 g/L) at. 1 M HNO₃ suggest that branching in the alky group of amides suppresses the extraction considerably. In view of the selective extraction of U over Th by 5 % TBP in THOREX process at 4 M HNO₃, distribution behaviour is also studied employing a lower concenfration (0·18 M) of extractant for comparison purpose, Separation factor (S. F.) values for U(VI) over Th(IV) under different experimental conditions consistently varied in the order: D2EHIBA > DHHA > TEHP > TBP. The quantitative extraction of ²³³U from a synthetic mixture containing ²³³U (10^?5 M). ²³³Pa (10^?11 M) and thorium (220 g/L) at 1 M HNO₃ using 1 M solution of D2EHIBA in n-dodecane is achieved in three stages, Stripping and reusability studies of D2EHIBA have also been carried out.     

Studies on Transport of Anionic Complex of Plutonium From Nitric Acid Medium across ALIQUAT 336/n-Paraffin Liquid Membrane

The present studies deal with the application of the supported liquid membrane (SLM) technique for the separation and purification of plutonium from other impurities in nitric acid medium using anion exchanger Aliquat 336 (a quaternary ammonium salt)/ n-paraffin as a carrier. The effects of feed acidity, stripping agent, and membrane pore size and membrane thickness on the transport behavior of anionic complex of plutonium have been studied in detail. An attempt has been made to establish the mechanism for plutonium transport and model the physicochemical transport of plutonium across SLM. Transport of anionic complex of plutonium increased with increase in carrier concentration upto 10% (w/v), while with further increase in carrier concentration, decrease in transport of plutonium was observed. The PTFE membrane with 0.45 µm pore size and 80 µm thickness was found to be most suitable for the transport of plutonium. The effect of membrane thickness indicates that the transport phenomenon is diffusion controlled. Transport behavior of plutonium, uranium, and other fission products from actual feed solution of ion exchange method obtained in PUREX process was also tested and the result clearly indicates that Aliquat 336 has high selectivity for plutonium and it can be used for the separation and purification of plutonium by the supported liquid membrane technique.     

Uranium Permeation from Nitrate Medium Across Supported Liquid Membrane Containing Acidic Organophosphorous Extractants and their Mixtures with Neutral Oxodonors

Permeation of U(VI) from nitric acid solution has been studied across supported liquid membrane (SLM) using bis[2,4,4 trimethyl pentyl] phosphinic acid (Cyanex 272) either alone or in combination with neutral donors like Cyanex 923 (a mixture of four trialkyl phosphine oxides viz. R₃PO, R₂R′PO, RR′₂PO, and R′₃PO where R: n-octyl and R′: n-hexyl chain), TBP (tri-n-butyl phosphate), and TEHP (tris-2-ethylhexyl phosphate) dissolved in n-paraffin as carriers. Effect of various other parameters such as nature and concentration of receiver phase, feed acidity, uranium concentration, pore size, and membrane thickness on U(VI) transport across SLM were investigated. Transport behavior of U(VI) was also compared with other derivatives of phosphoric acids like 2-ethylhexyl phosphonic acid-mono-2-ethylhexyl ester (PC88A), dinonyl phenyl phosphoric acid (DNPPA) under identical conditions and it followed the order: Cyanex 272 > PC88A > DNPPA. 2 M H₂SO₄ was suitable for effective U(VI) transport across SLM. Presence of neutral donors in carrier showed significant enhancement in U(VI) permeation in the order: Cyanex 923 > TBP > TEHP. U(VI) transport decreased with increased membrane thickness as well as decrease in pore size. The optimized conditions were tested for recovery of U(VI) from uranyl nitrate raffinate (UNR) waste generated during purification of uranium.     

Coupled transport of Pb2+ through tri‐n‐octylamine‐xylene‐polypropylene supported liquid membranes

Transport of Pb²⁺ was carried from acidic solution into alkaline stripping phase through tri‐n‐octylamine‐xylene‐polypropylene supported liquid membrane. The transport of Pb²⁺ through the membrane was studied by varying the concentration of Pb²⁺ and HNO₃ in feed solution, NaOH concentration in strip solution and TOA concentration in membrane phase. The flux data obtained has been used to study the stoichiometry of complex Pb(NO₃)_n+2(HNR₃)_n. The supported liquid membrane (SLM) has been found stable for 10 runs with 24 h between each run. This SLM has been used effectively to extract lead ions along with chromium, copper and zinc ions from aqueous acidic leached solution of paint and industrial effluents. © 2012 Canadian Society for Chemical Engineering     

Separation of Carrier-Free 90Y from 90Sr by SLM Technique Using D2EHPA in N-Dodecane as Carrier

Solvent extraction studies on Sr²⁺ and Y³⁺ are carried out from varying concentrations (0.01–6.0 M) of nitric acid using di-(2-ethylhexyl)phosphoric acid (D2EHPA) as extractant. Extraction of yttrium is observed to be higher than that of strontium at all the acidities and is found to increase substantially with decreasing concentration of nitric acid. Practically negligible extraction (D < 10^?3) of Sr²⁺ is observed from feed solutions containing nitric acid in the range of 1.0 to 4.0 M. These solvent extraction data are used to optimize the transport of ⁹⁰Sr and ⁹⁰Y across the supported liquid membrane (SLM) individually as well as from their mixture (due to insitue growth) under different experimental conditions. Selective separation of ⁹⁰Y (>90%) from ⁹⁰Sr is obtained in 6 h, when the concentration of nitric acid in feed is kept at 1.0 M and that of receiving phase is maintained at 4.0 M. 20% D2EHPA in n-dodecane is found to be the optimum carrier concentration for the efficient transport of ⁹⁰Y in SLM mode. Under these conditions transport of strontium is found to be negligible. Radiochemical purity of the product ⁹⁰Y is checked by following its decay as well as by extraction paper chromatography. The contamination of ⁹⁰Sr in ⁹⁰Y product is found to be < 0.001%. Based on the experimental results, a single stage SLM system for the generation of carrier-free ⁹⁰Y from ⁹⁰Sr source is described. The system is amenable for automation and scale up.     

PHENOLIC WASTEWATER TREATMENT BY SUPPORTED LIQUID MEMBRANE USING DIFFERENT COOKING OILS AS LIQUID MEMBRANE

Transport of phenol through a flat sheet supported liquid membrane (SLM) containing cooking oil as liquid membrane (LM) was investigated. Factors affecting permeation of phenol such as membrane phase, support material, feed phase pH, stripping phase concentration, stirring speed, and initial concentration of phenol were studied. It was found that these parameters strongly influence phenol removal efficiency; PTFE membrane as support material, grape seed oil as liquid membrane, feed pH of 2.0, initial phenol concentration of 100 mg/L, stirring speed of 350 rpm, and 0.2 M sodium hydroxide as effective stripping agent were found as the best conditions for greater phenol transport. Under these conditions, permeability was found to be 7.46 × 10^?6 m/s. After 10.5 h, phenol was completely removed from the feed phase to strip phase. According to stability experiments, it was observed that the SLM is stable after 22 h. Thus, the use of cheap, nontoxic, and naturally oil as a novel and green membrane for recovery of phenol from wastewater was demonstrated.     

Ion‐Exchange Separation of Pu from Macro Concentration of Th in HNO3 Medium

Abstract

Sorption behavior of Th and Pu from anion‐ as well as cation‐exchange resin was investigated from nitric acid medium by both batch and column methods. The anion‐exchange studies involved anionic nitrate complexes of Pu⁴⁺ and Th⁴⁺ sorbed onto DOWEX 1x4 resin (50–100 mesh), and the cation‐exchange studies involved the sorption of Pu³⁺ and Th⁴⁺ onto BIORAD AG 50Wx8 (50–100 mesh) or DOWEX 50Wx4 (50–100 mesh) resin. The batch data gave a separation factor (K _d,Pu/K _d,Th) of 22 for the anion‐exchange method and 0.017 for the cation‐exchange method at 3 and 2 M HNO₃, respectively. A two‐stage ion‐exchange separation method was developed for the quantitative separation of Pu (8 g/L) from a macro amount of Th (200 g/L) in nitric acid medium. The first step involved the quantitative sorption of plutonium from the mixture while about 90% of Th could be washed in 6 column volumes. The plutonium, eluted (as Pu³⁺) using 0.5 M HNO₃ + 0.2 M hydrazinium nitrate (HN) + 0.2 M hydroxyl ammonium nitrate (HAN), and the residual (～10%) Th were subsequently loaded onto a cation‐exchange column in the second step. Greater than 99% Pu was recovered with 2 M HNO₃ (in ～8 column volumes) containing 0.2 M HN + 0.2 M HAN. The final elution of thorium from the cation‐exchange column was achieved in about 6 column volumes of 1 M α‐hydroxy isobutyric acid. A (Pu, Th)O₂ fuel scrap sample was dissolved in 16 M HNO₃ containing 0.005 M HF and was used subsequently as the feed for the anion‐exchange column. The eluted Pu was subsequently loaded onto a cation‐exchange column for final purification. The recovery of plutonium and thorium was found to be >99% and >98%, respectively, while the respective decontamination factors were estimated to be 215 and 292.     

巯基乙酸2—乙基己酯的合成

本文介绍了巯基乙酸2-乙基己酯产品的用途、性能以及合成路线。以2-乙基己醇和氯乙酸为起始反应原料,采用先酯化后巯基化的合成工艺,催化剂活性高、反应步骤少、产品收率高,解决了先巯基化后酯化工艺过程复杂、对巯基乙酸纯度要求高、生产成本高的难题,是具有较高工业化实践价值的新生产工艺。     

Studies on Permeation of Nd (III) through Supported Liquid Membrane Using DNPPA + TOPO as Carrier

The transport behavior of Nd (III) through a supported liquid membrane (SLM) containing PTFE as support with organophosphorus extractant dinonyl phenyl phosphoric acid (DNPPA) carrier has been studied. The effect of neutral donors such as TOPO (tri-n-octyl phosphine oxide) TBP (tri-n-butyl phosphate), TEHP (tris 2-ethylhexyl phosphate) and Cyanex 923 (a mixture of four trialkyl phosphine oxides) in combination with DNPPA on transport of Nd (III) from HCl across SLM has been examined and the following trend was observed: TOPO > Cyanex 923 > TBP > TEHP. The effect of experimental variables such as feed acidity (0.5 to 5 M HCl), neodymium metal ion concentration (6.94 × 10^?4 to 6.94 × 10^?3 M), DNPPA concentration (0.2 to 0.6 M), stripping reagents in the receiving phase on Nd (III) transport across SLM were investigated. The percentage transport of Nd (III) was 97% after 6 hr run with 0.6 MDNPPA + 0.13 MTOPO as carrier. The permeability of Nd (III) decreased with increase in HCl and Nd (III) concentration in the feed solution. The transport of Nd (III) decreased with increase in membrane thickness as well as with decrease in pore size. Under optimized conditions transport behavior of other rare earths was also investigated independently, the trend observed was: La > Pr ≥ Nd > Sm > Eu > Gd > Tb > Dy > Ho > Er > Tm > Lu ≥ Y.     

Iridium(IV) Transport across Trioctylamine Supported Liquid Membrane

Abstract

Transport behavior of iridium through a supported liquid membrane (SLM) was investigated using trioctylamine (TOA) as a mobile carrier. Iridium(IV) was almost quantitatively extracted with TOA in kerosene from a low HCl solution, and extracted Ir(IV) was stripped with an HClO₄ or HNO₃ solution. Based on the extraction and stripping data, transport of Ir(IV) through a TOA-SLM was performed. Iridium(IV) in the feed solution with low HCl concentration was effectively transported into the HClO₄ or the HNO₃ product solution. Iridium(IV) was recovered and concentrated in the 1 M HClO₄ product solution by reducing the volume of strip solution relative to the volume of feed solution, yielding a sufficient enrichment factor.     

Selective Transport of Bismuth Ions through Supported Liquid Membrane

A new supported liquid membrane (SLM) system was prepared for the selective transport of bismuth ions from the aqueous feed into the aqueous permeate phase. The support of the SLM was a thin porous polypropylene or polyvinylidene fluoride membrane impregnated with diisooctyldithiophosphinic acid (Cyanex 301) as mobile carrier in 4‐chloroacetophenon as organic solvent. Cyanex 301 acts as a highly selective carrier for the uphill transport of bismuth ions through the SLM. In the presence of HNO₃ as a metal ion acceptor in the strip solution, the transport of bismuth ions into the strip side reached 70 % of the initial feed concentration after 3.5 hours. The selectivity and efficiency of bismuth transport from aqueous solutions containing different mixtures of cations were investigated. In the presence of P₂O₇^2– ions as suitable masking agent in the feed solution, the interfering effects of other cations were completely eliminated. The selective transport of bismuth through SLM is superior to liquid‐liquid extraction or through bulk liquid membranes. This is due to the high efficiency. The SLM reduces the solvent requirements, combines extraction and stripping operations in a single process and allows the use of highly selective extractants. The system may be applied to samples containing very low bismuth concentrations.     

Supported Liquid (SLM) and Polymer Inclusion (PIM) Membranes Pertraction of Copper(II) from Aqueous Nitrate Solutions by 1-Hexyl-2-Methylimidazole

The facilitated transport of Cu(II) ions from different aqueous nitrate source phases (c _Me = 0.001 M, pH = 6.0) across supported (SLMs) and polymer inclusion membranes (PIMs) doped with 1-hexyl-2-methylimidazole as ion carrier was reported. The membrane is characterized by means of atomic force microscopy (AFM). The results show that Cu²⁺ can be separated very effectively from other transition metal cations as Zn²⁺, Co²⁺, and Ni²⁺ from different equimolar mixtures of these ions. The highest initial fluxes of Cu(II) were found for PIM, while lower values were observed for SLM. However, after taking into account the morphology of the membranes (porosity, tortuosity), the values of the initial flux of Cu(II) transport across PIM is less than that across SLM. The recovery factor of Cu²⁺ ions during transport across PIM from different mixtures of cations is above 91% after 24 hrs and above 76% during transport across SLM. Also, the stability of PIM and SLM doped with 1-hexyl-2-methylimidazole was confirmed in replicate experiments.