ES2502069A1 - Polymeric inclusion membranes based on ionic liquids (Machine-translation by Google Translate, not legally binding) - Google Patents

Abstract

Polymeric inclusion membranes based on ionic liquids. # The present invention relates to an inclusion polymeric membrane comprising a base polymer, an extracting agent and a plasticizing agent where the extracting agent and the plasticizing agent is an ionic liquid, the The invention also relates to the use of said membranes in microbial fuel cells, the use thereof for the selective separation of mixtures of organic acids, alcohols and esters and the use thereof as immobilization matrices of chemical, biochemical and / or biological

Description

P201330453

03-27-2013

POLYMERIC INCLUSION MEMBERS BASED ON ION LIQUIDS

Field of the Invention

The present invention is generally framed in the field of materials chemistry and in particular refers to polymeric inclusion membranes based on ionic liquids and the use thereof.

State of the art

Research and development in membranes is one of the research activities that are devoting more technological resources, since the commercialization of these 10 new technological developments is generating sales of over one billion dollars annually.

However, despite the market boom of most types of membranes, such as filtration membranes, electrodialysis membranes, in the case of liquid membranes, such as liquid membranes (BLM), liquid membranes in

15 emulsion (ELM) and supported liquid membranes (MFEE), its practical application remains largely limited.

Although its formulation, properties and applications have been studied on a laboratory scale, its application on an industrial scale is limited mainly due to their insufficient operational stability. In recent years, a

20 considerable effort in understanding and improving the stability of liquid membranes.

The formulation of a new type of liquid membrane known as polymeric inclusion membrane (PIM) has improved the stability of liquid membranes. A PIM consists of mixing a base polymer, which provides mechanical strength, a plasticizer or modifier, which provides elasticity and increases the solubility of the 25 species extracted in the liquid membrane phase, and a carrier (extractant) to facilitate selective transport. of the chemical species of interest, which normally consists of an organic solvent. Among the polymers most commonly used to form the gel-like network that traps the carrier and the plasticizer / modifier, are polyvinyl chloride (PVC) and cellulose triacetate (CTA). The nature of the plasticizer or modifier used to form the membrane is also a key parameter to consider. The plasticizers are

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organic compounds that incorporate a hydrophobic main alkyl chain and one or more highly solvating polar groups.

Ionic liquids (ILs) possess unique properties that are interesting in the context of liquid membranes. ILs are organic salts that are in a liquid state at room temperature. They are normally composed of an organic cation (for example, imidazolium, pyridinium, pyrrolidinium, phosphonium, ammonium), and an inorganic polyatomic anion (for example, tetrafluoroborate, hexafluorophosphate, chloride) or, more and more commonly, an organic anion (for example trifluoromethylsulfonate, bis [(trifluoromethyl) sulfonyl] imide). The main advantage of these means is its vapor pressure close to zero and its good chemical and thermal stability. Due to the above properties, they have been considered as benign solvents with the environment compared to volatile organic solvents. In addition, the properties of ionic liquids (hydrophobicity, viscosity, solubility, etc.) can be modulated by modifying the constituent anion or cation. In this way, specific ionic liquids can be achieved for each specific application, which has allowed its use in many fields of chemistry. In fact, ionic liquids have been used as substitutes for volatile organic solvents in a wide variety of chemical processes on a laboratory scale, such as the separation and purification of biochemical reaction media and catalysts.

The use of these new solvents as a liquid phase in liquid membranes leads to a stabilization of the membranes due to their minimum vapor pressure and the possibility of minimizing their solubility in the surrounding phases by proper selection of the cation and the constituent anion. Other interesting properties of ionic liquids in the context of liquid membranes are their high ionic conductivity and high power as a solvent. All these mentioned properties have led ILs to be considered as "green design solvents". In addition, in the context of PIMs, some ionic liquids have the added advantage of acting as an extraction agent and as a plasticizer at the same time.

In the last decade, the use of supported liquid membranes (SLMs) based on ILs for the selective separation of organic compounds such as amines, alcohols, organic acids, ketones, ethers and aromatic hydrocarbons, as well as mixtures has been described in the scientific literature. of gases and metal ions. However, these SLMs have generally shown limited stability primarily to highly media.

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polar such as water, which could be improved by the use of polymeric inclusion membranes.

Microbial fuel cells (MFCs) are bioelectrochemical devices capable of directly converting chemical energy into electricity, using a wide range of organic substrates for this purpose. Historically, pure substrates such as acetate, glucose and / or lactate have been used to feed the MFCs. In 2000, wastewater and other complex mixtures began to be used as organic substrates in microbial fuel cells. One of the critical components that determine the efficiency of CFMs is the proton exchange membrane (PEM). Nafion® has been widely used as a PEM in microbial batteries, due to its high proton conductivity. However, this membrane is still very expensive, which makes its use prohibitive in large-scale applications.

Recently, new supported liquid membranes (SLMs) formed by ionic liquids embedded in the pores of a polymeric support by occlusion applying pressure have been designed. These new membranes have been used as new proton exchange (PEM) membranes in microbial fuel cells. The replacement of the membranes conventionally used by these new membranes allows a cost reduction of approximately 70%. However, the use of these membranes in microbial fuel cells that use wastewater as a substrate was still limited to highly hydrophobic ionic liquids, since hydrophilic acids are easily solubilized in a highly polar phase such as water. Therefore, it seems interesting to find an approach that broadens the range of ionic liquids for use in proton exchange membranes in CFM. Therefore, polymeric inclusion membranes based on ionic liquids are proposed as a potential solution.

The present invention solves the problems described in the state of the art since it refers to polymeric inclusion membranes based on ionic liquids that could be applied as efficient membranes in microbial fuel cells, in the selective separation of mixtures of organic acids, alcohols and esters and as means for immobilization of chemical catalysts and biocatalysts, as well as animal and plant cells. In such a way that the mechanical and thermal stability of the liquid membranes based on ionic liquids and their chemical stability is increased both to highly polar media, such as water, as to apolar media such as n-hexane.

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Description of the invention

Thus the present invention in a first aspect relates to an inclusion polymeric membrane (hereafter referred to as the membrane of the present invention) comprising at least one base polymer, an extracting agent and a characterized plasticizing agent.

5 because the extraction agent and the plasticizing agent is an ionic liquid selected from the general formulas I-VIII:

(I) (II)

image 1 image2 R1 CH

R1

image3 3 R2 image4

image5 R2 image6 N

X-n

X-n

AA

R3 R3

n

n

10 (III)

image7

(IV) (V)

R1 image8 R1 CH3

image9 R7

R7

X-n X-n

V V U

W R8 W R8

n n

(VI) (VII) (VIII)

R image10 10 R11 R image11 10 R11 R image12 10 R11

X-n X-n X-n

image13 N image14 S

R12 R13 R12 R13 R12

n n

where:

A is selected from -N- or C (R4),

B is selected from -O-, S, or N (R5),

U, V, W are selected from -N- or C (R10), where U and V are not -N5 simultaneously,

Z is selected from -O- or N (R12),

X is an anion,

n is an integer from 1 to 4,

R1-R16 are the same or different and where R is selected from hydrogen, a group

C1-C18 alkyl, C2-C18 alkenyl, C2-C18 alkynyl, substituted C1-C18 alkyl, substituted C1-C18 alkenyl, substituted C1-C18 alkynyl, C3-C8 cycloalkyl, C3-C8 cycloalkenyl, aryl, substituted aryl, aryl (C1-C4 alkyl) or aryl (C1-C4 alkyl) substituted.

In a preferred embodiment, X is selected from the anions: hydroxide, chloride, bromide, iodide, borate, tetrafluoroborate, cuprate, Cu (I) Cl2, phosphate anion,

15 hexafluorophosphate, hexafluoroantimoniate, perchlorate, nitrate, sulfate, carboxylate, sulphonate, sulfoimide, phosphate, alkyl carbonate, dicianamide, thiocyanate or tricianomethane.

In the present invention the term "C1-C18 alkyl" refers to a linear or branched monovalent chain of one to eighteen carbon atoms, such as butyl, octyl, 2-methyldodecyl, and the like.

In the present invention the term "substituted C1-C18 alkyl" refers to a C1-C18 alkyl chain as described above, where one or more hydrogen atoms in the alkyl chain are substituted with monovalent groups, such as halide, haloalkyl, alkoxy, haloalkoxy, alkylthio, haloalkylthio, alkylamino, alkanoyl, cyano, nitro and the like.

In the present invention the term "C2-C18 alkenyl" refers to a linear or branched monovalent chain of two to eighteen carbon atoms containing one or more double bonds, for example, ethenyl, 2-propenyl, 3-methyl- 3-butenyl methyl and the like.

In the present invention the term "substituted C1-C18 alkenyl" refers to a C1-C18 alkenyl as described above, where one or more hydrogen atoms in the alkyl chain are substituted with monovalent groups, such as halo, haloalkyl. , alkoxy, haloalkoxy, alkylthio, haloalkylthio, alkylamino, alkanoyl, cyano, nitro and the like.

In the present invention the term "C2-C18 alkynyl" refers to a linear or branched monovalent chain of two to eighteen carbon atoms containing one or more triple 5 bonds, for example ethynyl, 2-propynyl, 3-methyl-3 -butyl methyl and the like.

In the present invention the term "substituted C1-C18 alkynyl" refers to C1-C18 alkynyl as described in the preceding paragraph, where one or more hydrogen atoms in the alkyl chain are substituted with monovalent groups, such as halo , haloalkyl, alkoxy, haloalkoxy, alkylthio, haloalkylthio, alkylamino, alkanoyl, cyano, nitro and the like.

In the present invention the term "C2-C8 cycloalkyl" refers to a linear monovalent chain of three to eight carbon atoms that form a cyclic structure, such as cyclopropyl, cyclohexylmethyl, α-methyl-2-methylcyclopentylmethyl and the like.

In the present invention the term "C3-C8 cycloalkenyl" refers to a monovalent chain of three to eight carbon atoms containing one or more double bonds that

15 form a cyclic structure, such as 2-cyclopropylenyl, cyclohex-2-enylmethyl, α-methyl-5-methylcyclopent-2-enylmethyl, and the like.

In the present invention the term "aryl" refers to a cyclic aromatic radical such as phenyl, naphthyl, pyridyl, and the like, which may optionally contain one or more other heteroatoms, such as oxygen, nitrogen, and sulfur.

In the present invention the term "substituted aryl" refers to the aryl radical described above, wherein from one to three hydrogen atoms of the aryl are substituted with monovalent groups, such as halide, alkyl, haloalkyl, alkoxy, haloalkoxy, alkylthio, haloalkylthio, alkylamino, alkanoyl, cyano, nitro, and the like.

In the present invention the term "halo" refers to one or more halogen substituents belonging to the group consisting of fluorine, chlorine, bromine, and iodine.

In the present invention the term "alkoxy" refers to a linear or branched monovalent chain of carbon and oxygen atoms, such as methoxy, butoxy, 2,4-dimethylbutoxy, and the like.

In the present invention the term "alkylthio" refers to a linear monovalent chain.

30 or branched carbon and sulfur atoms, such as methylthio, butylthio, 2,4-dimethylbutylthio, and the like.

In the present invention the term "alkylamino" refers to one or two alkyl groups independently each being a linear or branched monovalent chain of carbon and nitrogen atoms, such as methylamino, dibutylamino, N- (2,4-dimethylbutyl) ) N-methylamino, and the like.

In the present invention the term "alkanoyl" refers to a linear or branched monovalent chain of carbon atoms and a carbonyl group, such as acetyl, butanoyl, 2,4-dimethylbutanoyl, and the like.

It will be appreciated that the above terms can be combined resulting in new chemical structures. Therefore, "haloalkyl" refers to an alkyl, as defined above, substituted by halogen, also defined above, for example, trifluoromethyl, 2,2-difluoro-1-bromoethyl, 3,3,3,2 , 1,1-heptafluoro-2-trifluoromethylpropyl, and the like.

Carboxylate anions include alkyl carboxylates, such as acetate, substituted alkyl carboxylates, such as lactate and haloalkyl carboxylates, such as trifluoroacetate, and the like.

Carbonate anions include alkyl carbonates such as methyl carbonates and substituted alkyl carbonates.

Sulfonate anions include alkyl sulfonates such as mesylate, haloalkylsulfonates, such as triflate and nonaflate, and aryl sulfonates such as tosylate and mesylate and the like.

Sulfonimide anions include mono- or disubstituted sulfonimides, such as methanesulfonimide and bisetanosulfonimide, and halogenated sulfonimides, such as bis trifluoromethanesulfonimide, arylsulfonimides, such as bis (4-methoxybenzene) sulfonamide, and the like.

Phosphonate anions include alkyl phosphonates, such as tert-butyl phosphonate, aryl phosphonates, such as 3,4-dichlorophenylphosphonate and the like.

In a more particular embodiment, the ionic liquid used as a plasticizer and extraction agent for the preparation of PIMs is a compound selected from the group of imidazolium salts, pyrazolium salts, oxazolium salts, thiazolium salts, triazolium salts, pyridinium salts, pyridacinium salts, pyrimidinium salts, pyrazinium salts, piperidinium salts, morpholinium salts, pyrrolidinium salts, ammonium salts, phosphonium salts or sulfonium salts. Illustrative of such compounds are 1-ethyl-3-methylimidazolium chloride, 1-butyl-3-ethylimidazolium chloride, 1-butyl-3-methylimidazolium chloride, 1-butyl-3-methylimidazolium bromide, 1-methyl- chloride 3-propylimidazolium, 1-methyl-3-hexylimidazolium chloride, 1-methyl-3-octylimidazolium chloride, 1-methyl-3-decylimidazolium chloride, 1-methyl-3-dodecylimidazolium chloride, 1-methyl-3- chloride hexadecylimidazolium, 1-methyl-3-octadecylimidazolium chloride, 1-ethylpyridinium bromide, 1-ethylpyridinium chloride, 1-butyl pyridinium chloride, 1-benzylpyridinium bromide, 1-butyl-3-methylimidazolium tetrafluoroborate, and 1-methylimidazolium tetrafluoroborate, -3-methylimidazolium, 1-butyl-3-methylimidazolium nitrate, 1-ethyl-3-methylimidazolium tetrafluoroborate, 1-ethyl-3-methylimidazolium bromide, 1-ethyl-3-methylimidazolium iodide, 1-ethyl-3 nitrate -methylimidazolium, 1-butyl pyridinium tetrafluoroborate, 1-butyl pyridinium bromide, 1-butyl pyridinium iodide, 1-butyl pyridinium nitrate, hexafluoropho 1-Butylimidazolium phosphate, 1-octyl-3-methylimidazolium tetrafluoroborate, 1-ethyl-3-methylimidazolium ethyl sulfate, 1-butyl-3-methylimidazolium triflate, 1-butyl-3-methylimidazolium triflate, 1- 1- trifluoroacetate acetate Butyl-3-methylimidazolium and 1-butyl-3-methylimidazolium bis (trifluoromethanesulfonimide) trifluoroacetate.

In a preferred embodiment, the membrane base polymer of the present invention is an organic polymer.

In another aspect, the present invention relates to the use of the membrane of the present invention in microbial fuel cells.

In another aspect, the present invention relates to the use of the membrane of the present invention for the selective separation of mixtures of organic acids, alcohols and esters.

In another aspect, the present invention relates to the use of the membrane of the present invention as an immobilization matrix more particularly, as an immobilization matrix for chemical, biochemical and / or biological catalysts such as animal and plant cells.

Description of the figures

Figure 1 shows the voltage profiles over time for an MFC containing (i) an inclusion polymeric membrane of 50% composition of [MTOA +] [Cl -] and 50% PVC and (ii) a Nafion®117 membrane .

Figure 2 shows photographs of (i) PIM of Nafion® 117 and (ii) PIM based on ionic liquids, after one week of operation in a microbial fuel cell.

Detailed description of the invention

Below are four particular examples where the invention described above is described. The examples should not be construed as limiting the invention in terms of the materials, conditions, or process parameters contained therein.

PIMs were obtained by casting methods using PVC and ionic liquids (ionic liquid content of 20 to 80% w / w). The preparation of the PIMs was carried out by dissolving the corresponding amounts of an IL and a base polymer in an organic solvent, as shown in the following examples. The mixture was poured onto a glass plate, and inside a glass ring when the thickness needs to be controlled. The solvent was allowed to evaporate overnight and the membrane formed carefully peeled off the glass plate.

Example 1: Preparation of a polymeric inclusion membrane of composition 50% [MTOA +] [Cl -] -50% PVC

The polymeric membrane inclusion composition 50% [MTOA +] [Cl-] -50% PVC was prepared by casting a polymer solution containing 50% by weight of methyltrioctylammonium chloride ([MTOA +] [Cl -] ) and 50% by weight of polyvinyl chloride (PVC). For this, the corresponding weight of PVC (150 mg) and [MTOA +] [Cl -] (150 mg) was dissolved in 3 mL of tetrahydrofuran (THF). Subsequently, this solution was poured into a glass ring, 28 mm internal diameter and 30 mm high, fixed by elastic rubber to a glass plate. The membrane was obtained by evaporation of THF at room temperature overnight.

Example 2: Use of polymeric inclusion membranes of composition 50% [MTOA +] [Cl-] -50% PVC as membranes in microbial fuel cells

The polymeric inclusion membrane of composition 50% [MTOA +] [Cl -] -50% PVC was prepared by the method described in example 1.

The reactors were built with two 250mL jacketed glass jars (Schott Duran®, Germany), modified with a cylindrical flange. The jackets had a capacity of 150 mL and a thermostatic liquid circulated that controlled the reactor temperature at 30 ° C. The thermostatic fluid was heated by a thermostatic bath. The fuel added to the anodic chamber consisted of wastewater from the barley processing of a brewery, diluted in domestic wastewater to give a chemical oxygen demand (COD) of 1200 mg L-1. All the experiments analyzed were performed in batch mode, with wastewater being the only fuel and source of microorganisms.

The described experiments are carried out MFCs of a camera. Each anode consisted of 100 cm3 of graphite granules of 2 mm in diameter and a graphite rod of 3.18 mm in diameter, which served to connect to the cathode terminal through a 1 k� resistor. The anodic chambers were filled with 100 mL of fuel. To obtain the platinum catalyst, a PVC platinum suspension was dispersed on a 4cm diameter carbon cloth until the final electrode weight was 0.3 mg cm-2 in all cases. The PIM was placed on the cathode and the assembly was fixed on the circular flange using a round clamp.

Figure 1 shows the voltage versus time profiles for an MFC containing

(i) a 50% inclusion polymeric membrane [MTOA +] [Cl -] -50% PVC and (ii) a Nafion®117 membrane. As can be seen, for the PIM, the maximum voltage output was 360 mV at 5 hours, decreasing to 200 mV at 60 hours and staying around this value until 105 hours. In the case of the MFC based on the Nafion®117 membrane, the maximum voltage was significantly lower, around 125 mV at 5 hours, decreasing to 90 mV at 100 hours.

The capacity for wastewater treatment was evaluated in terms of COD removal (COD). The elimination of soluble COD (COD) is defined as the ratio between the total COD consumed in the process and the initial COD, with the COD consumed being the difference between the initial chemical oxygen demand [COD] 0 and the chemical oxygen demand at one point:

[1] The DQOR in the experimental time was 89.1% for the CFM using a PIM with [MTOA +] [Cl -] at 50% by weight, this being similar to the DQOR obtained with a Nafion®117 membrane ( 90.7% at the end of the experiment).

image15

Therefore, if we compare the voltage and the COD as a whole for both membranes, it can be seen how similar or even better results are achieved using polymeric inclusion membranes based on ionic liquids than those obtained with conventional Nafion® membranes117.

We can also compare the external appearance of both membranes, (see Figure 2), observing that the inclusion polymeric membranes based on ionic liquids have the added advantage over the Nafion®117 membrane that they do not show fouling problems, so can consider as "antifouling" membranes.

Example 3: Stability of an inclusion polymeric membrane of composition 30% [bmim +] [NTF2-] -70% PVC in highly polar media.

-

The polymeric inclusion membrane of composition 30% [bmim +] [NTF2] -70% PVC was prepared by casting a polymer solution containing 30% by weight of 1

-

butyl-3-methyl imidazolium bis (trifluoromethanesulfonimide), [bmim +] [NTF2] and 70% by weight of polyvinyl chloride (PVC). For this, the corresponding weight of PVC (210 mg) and [bmim +] [NTf2-] (90 mg) was dissolved in 3 mL of THF. Subsequently, this solution was poured into a glass ring of 28 mm internal diameter and 30 mm high, fixed by an elastic rubber to a glass plate. The membrane was obtained by evaporation of THF at room temperature overnight.

Stability studies were performed at 30 ° C using a glass diffusion cell with two independent compartments, each 30 mL, separated by the PIM. O-rings were inserted on each side of the PIM to maintain tightness. The whole assembly was held together by a threaded connector. The water stability of the membrane was evaluated for which distilled water was used as the feeding and receiving phase, both compartments being mechanically agitated. Stability was measured in four cycles of 24 hours each. After each cycle, the membrane was removed and allowed to dry at room temperature, the weight loss was calculated.

In each cycle the water of the feeding and receiving phase was renewed. The stability of the PIM was measured by weight loss in each cycle. The ionic liquid immobilized on the membrane was 93.4 mg. The weight loss after the first cycle was 10%. After the first cycle, the weight loss was negligible in the next 3 cycles. In the case of supported liquid membranes (SLMs) based on the ionic liquid 1-butyl-3-methylimidazolium bis (trifluoromethanesulfonimide), [bmim +] [NTf2-] immobilized on a Nylon® membrane, the loss of ionic liquid was close to 100% . This fact demonstrates that polymeric inclusion membranes represent an excellent methodology for stabilizing membranes based on ionic liquids to highly polar media.

The ionic liquids of the present invention can be prepared by any of the preparation methods described in the scientific literature, such as metathesis with a halide salt and by acid-base neutralization reactions.

The examples demonstrated that the membranes of the present invention were more stable against aqueous media than conventional supported liquid membranes based on ionic liquids (SILMs) prepared by absorption of the ionic liquid in a porous organic polymer, such as Nylon®. For example, it should be noted that the ionic liquid absorbed in a Nylon® membrane was almost completely lost when ionic liquids such as 1-butyl-3-methylimidazolium hexafluorophosphate, [bmim +] [PF6-], and 1-butyl-3-methylimidazolium were absorbed -bis (trifluoromethanesulfonimide), [bmim +] [NTf2-], after a week immersion of the SILM in aqueous medium, while only 10% losses of the same ionic liquids were observed when immobilized as PIM by the technique of "casting". It should be noted that the use of "casting" methods also allowed the immobilization of a greater amount of ionic liquid (50mg / cm2) with respect to immobilization by absorption in a porous Nylon® material (18mg / cm2), which could improve the proton conductivity and selectivity of the resulting membranes for application as PEMs in MFC and in separation operations. In addition, these membranes did not present fouling problems and, therefore, can be considered as "antifouling" membranes.

Claims (5)

1. Polymeric inclusion membrane comprising at least one base polymer, an extracting agent and a plasticizing agent characterized in that the extracting agent and the plasticizing agent is an ionic liquid selected from the general formulas 1-VIII: 5 (1) (11) R1 R1 eH  \ 1 3 FOR YOU image 1 X-TI / + y §2YR2) -B R2 R3 R3 n n (111) R1 I R2 image2 X-fi AB eleven 10 (IV) (V) R1 R1 I eH3 7 \ / 7 X-TI X-TI  / NKR (XR 18  u, u, W R8 W R8 n n (VI) (VII) (VIII) R10 Rll R10 Rll R10 Rll '\. + / X-n' \. + / X-n "" + / X-n S / N "/ p '\. R12 R13 R12 R13 RI 12 n n where: 15 A is selected from -N-o C (R4), 14 B is selected from -0-, S, or N (R5), u, V, W are selected from -N-o C (R10), where U and V are not -Nsimultaneously, Z is selected from -0- or N (R12), 5 X is an anion, n is an integer from 1 to 4, R1_R 16 are the same or different and is selected from hydrogen, a group C1-C18 alkyl, C2-C18 alkenyl, C2-C18 alkynyl, substituted C1-C18 alkyl, substituted C1-C18 alkenyl, substituted C1-C18 alkynyl, C3 cycloalkyl -C8, C3-C8 cycloalkenyl, aryl, aryl 10 substituted, aryl (C1-C4 alkyl) or aryl (C1-C4 alkyl) substituted. 2. Membrane according to claim 1 wherein X is selected from the anions: hydroxide, chloride, bromide, iodide, borate, tetrafluoroborate, cuprate, Cu (I) CI2, phosphate anion, hexafluorophosphate, hexafluoroantimonate, perchlorate, nitrate, sulfate, carboxylate , sulphonate, sulfoimide, phosphate, alkyl carbonate, dicianamide, thiocyanate or tricianomethane. 3. Membrane according to any of the preceding claims, wherein the base polymer is an organic polymer.

Four.

Use of a polymeric membrane according to any of claims 1-3 in microbial fuel cells.

5.

Use of a polymeric membrane according to any of claims 1-3, for the selective separation of mixtures of organic acids, alcohols and esters.

6.

Use of a polymeric membrane according to any of claims 1-3, as an immobilization matrix of chemical, biochemical and / or biological products.

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