Membrane protection layer for electrochemical systems and processes

Abstract

Provided herein is a membrane protection layer associated with a separation membrane, electrochemical systems including the same, and uses thereof for various electrochemical processes, such as, for example, purification of wastewater and / or production of hydrogen. Further provided are purification systems including the membrane protection layer and uses thereof for various purification processes.

Description

[0001] MEMBRANE PROTECTION LAYER FOR ELECTROCHEMICAL SYSTEMS AND PROCESSES

[0002] TECHNICAL FIELD

[0003] The present disclosure relates generally to a membrane protection layer, electrochemical systems including the same, and uses thereof in various electrochemical processes, such as, for example, purification of wastewater and / or production of hydrogen.

[0004] BACKGROUND

[0005] Water treatment, particularly wastewater treatment, plays a crucial role in safeguarding the environment and providing clean water for consumption. There are several technologies available to carry out this process, and one of the most energy -efficient methods used for wastewater treatment is electrochemistry. Electrochemistry focuses on four primary methods: electrodeposition, electrocoagulation (EC), electroflotation (EF), and electrooxidation. Indirect electrooxidation is a specific method that involves the anodic oxidation of an initial reactant to produce an intermediate oxidative reactant. This intermediate reactant then oxidizes a pollutant of concern, resulting in cleaner water.

[0006] An electrochemical system includes four key components: a power supply, an anolyte, a catholyte, and a membrane that separates the two compartments. The membrane is an ion exchange membrane that can transfer specific charged species (ions) from one compartment to another while restricting the transfer of other species. However, such membrane is relatively sensitive and prone to instability when exposed to oxidizing or reducing environments, such as the harsh environment of wastewater in general, and wastewater containing oxidative reactants in particular.

[0007] Consequently, as effective as the intermediate oxidative reactant is in oxidizing the pollutant of concern, it can also cause damage to the sensitive membrane material. This can pose a challenge to the robustness of the ion exchange membrane and the operation of the entire electrochemical system.

[0008] Accordingly, there is a need in the art for robust electrochemical systems and methods that protect separation membrane(s) in harsh conditions in an efficient and cost effective manner, without affecting the efficiency of the membrane and the electrochemical process. SUMMARY

[0009] The disclosure is directed, in embodiments thereof, to a protective layer of an ion exchange membrane (IEM), for use in various electrochemical systems, in particular, in systems which are operative under harsh conditions. In some embodiments, further provided herein are methods of utilizing the protective layer (PL) with the electrochemical system, for various processes, such as, for example, purification / treatment of a pollutant-containing solution, production of H2, and the like.

[0010] In some embodiments, such electrochemical systems may be utilized, for example, for various purification / treatment and / or production schemes, such as, Electrodialysis, (ED), Electrodeionization (EDI), pharmaceutical applications, production of chloralkaline for water treatment (for example, of wastewater), hybrid production-treatment (such as, wastewater purification on the anode and hydrogen gas generation on the cathode), and the like.

[0011] According to some embodiments, the advantageous protective layer disclosed herein is capable of prolonging the life-span of the IEM, without compromising the activity and efficiency thereof. Moreover, as further exemplified hereinbelow, the PL is advantageously capable of enhancing the robustness of the IEM in extreme oxidative / reductive conditions in general, and towards corrosive intermediate reactants in particular.

[0012] In some embodiments, the PL can be used, for example, in an electrochemical system, which includes at least two compartments separated by an ion exchange membrane (IEM) that is protected by the advantageous protective layer (PL). As a result, and in accordance with some embodiments, the protective layer can enhance IEM robustness by, for example, at least about 2-fold as compared to a system that does not include the PL.

[0013] Advantageously, in accordance with some embodiments, during the electrochemical reaction(s), a parallel electrolysis process may facilitate the production of EL, thereby enabling self-sustainable electrical energy usage.

[0014] According to some embodiments, there are provided herein methods for purification of pollutant-containing solutions with electrochemical systems, utilizing the membrane protective layer, as well as methods for preparing ion exchange membrane(s) (IEM) protected by the advantageous protective layer. According to some embodiments, there is provided an electrochemical system for purification of a pollutant-containing solution and / or production of H2, the electrochemical system includes: at least two liquid compartments, including an anolyte compartment configured to hold a solution, and a catholyte compartment; and an ion exchange membrane (IEM) separating the liquid compartments, said IEM is associated with at least one protective layer (PL) facing the anolyte compartment, wherein upon applying an electric field, initial reactant(s) in the anolyte compartment are electrochemically oxidized into corrosive intermediate reactants, said corrosive intermediate reactants are capable of reacting with one or more pollutant species in the solution, to convert said pollutant species into a non-pollutant species(s), thereby purifying the solution.

[0015] According to some embodiments, the IEM is selected from a cation exchange membrane (CEM), an anion exchange membrane (AEM), and a bipolar membrane (BPM).

[0016] According to some embodiments, the at least one PL facilitates passage of water and specific ions, while limiting contact of the intermediate reactants with the IEM.

[0017] According to some embodiments, the purified solution is being collected from the anolyte compartment.

[0018] According to some embodiments, the at least one PL may have a thickness of about 1 - 500 pm.

[0019] According to some embodiments, the at least one PL may include or be made of a porous polymer.

[0020] According to some embodiments, the at least one PL may include or be made of an electrically passive polymer.

[0021] According to some embodiments, the at least one PL may have an average pore size in the range of about 0.001-10 pm. According to some embodiments, the average pore size may be in the range of about 0.03-10 pm. According to some embodiments, the average pore size may be in the range of about 0.001-0.1 pm. According to some embodiments, the electrically passive porous polymer may include polyethylene, polypropylene, polyester, polystyrene, polymethylmethacrylate, polyvinylchloride (PVC), polyamide, polyvinylidendifluoride (PVDF), co-polymer based on the natural or synthetic rubber or thermoplastic elastomer, polytetrafluorethylene (Teflon), polyethersulfone (PES), any derivative thereof, any co-polymers thereof, or any combination thereof.

[0022] According to some embodiments, the at least one PL may be further impregnated or doped with conductive elements.

[0023] According to some embodiments, the system may further facilitate a reduction of NH3 pollutant level in the pollutant-containing solution.

[0024] According to some embodiments, the pollutant-containing solution may include wastewater, industrial waste stream, drinking water, biological fluid(s) (blood, urine, saliva), alkaline solution, acidic solution, alcohol, salted water, cell culture medium, food / feed- production related medium, chemical industry related medium, ion exchange brines, membrane filtration brines, or any combinations thereof. According to some embodiments, the solution may be wastewater.

[0025] According to some embodiments, the system includes a plurality of anolyte and catholyte compartment(s), each separated by an ion exchange membrane (IEM), associated with at least one protective layer (PL) facing the anolyte compartment.

[0026] According to some embodiments, an anode includes an oxidizing catalyst. In some embodiments, the oxidizing catalyst includes Ir, Ru, Ni, Ti, Pd, Sb, Sn, and / or Fe.

[0027] According to some embodiments, the initial reactant may include ions or compounds selected from: As, Hg, Cd, Zn, Ag, Cu, Fe, Cr, Ni, Pd, Pt, Sn, Sb, Ti, Ru, Ir, chloride ions, chlorite ions, sulfate ions, phosphate species, peroxymonosulfate ions, peroxy di sulfate ions, and derivatives thereof.

[0028] According to some embodiments, the corrosive intermediate reactant may include oxidized metal ions or compounds selected from: As, Hg, Cd, Zn, Ag, Cu, Fe, Cr, Ni, Pd, Pt, Ru, Ir, Sn, Sb, Ti, chlorine radicals, active chlorine species, chloramines, chlorate ions, chlorine dioxide, persulfates S20s2', peroxydiphosphate, peroxymonophosphoric acid, hydroxyl radicals, peroxide, ozone, sulfate radical, derivatives thereof, and any combinations thereof.

[0029] According to some embodiments, the pollutant may include inorganic compounds selected from ammoniacal nitrogen, urea, sulfides, metal salts, and any combination thereof.

[0030] According to some embodiments, the pollutant may include organic selected from: amino acids, lipids, carbohydrates, proteins, and any combination thereof.

[0031] According to some embodiments, the pollutant may include biological species selected from: cells, bacteria, viruses, and fungi.

[0032] According to some embodiments, the pollutant may include industrial chemical entities selected from: pharmaceuticals, dyes, polymers, and halogenated polymers and / or compounds.

[0033] According to some embodiments, the initial reactant includes chloride, the pollutant includes NH3, the corrosive intermediate reactant includes chloramine, and the non-pollutant product includes N2.

[0034] According to some embodiments, the at least one PL may extend the lifespan of the IEM by at least about 2-fold, compared to an IEM which is not associated with an at least one PL.

[0035] According to some embodiments, there is provided a method for purification of pollutant-containing solution and / or production of H2, the method includes: providing the electrochemical system as disclosed herein; introducing a pollutant-containing solution into the anolyte compartment; applying an electric field; and generating purified solution in the anolyte and / or producing H2 in the catholyte compartment.

[0036] According to some embodiments, introducing a pollutant-containing solution may further include adding an initial reactant. According to some embodiments, the catholyte compartment may be acidified / neutralized with an acid.

[0037] According to some embodiments, catholyte may be devoid of a solution.

[0038] According to some embodiments, there is provided a method of producing the protected IEM of the electrochemical system disclosed herein, the method includes; providing a flat surface; applying the PL; applying an IEM layer; and thereby, producing the IEM associated with the PL.

[0039] According to some embodiments, applying the PL may be performed prior to applying the IEM.

[0040] According to some embodiments, applying the IEM may be performed prior to applying the PL.

[0041] According to some embodiments, the IEM and / or PL, may be applied as a polymer.

[0042] According to some embodiments, the IEM and / or PL, may be applied as a monomer.

[0043] According to some embodiments, the applied monomer of the IEM may include an anionic and / or a cationic monomer.

[0044] According to some embodiments, the method may further include at least one polymerization step.

[0045] According to some embodiments, the at least polymerization step may be performed after applying the PL and / or the IEM.

[0046] According to some embodiments, the at least one polymerization step may further include a cross-linking step.

[0047] According to some embodiments, the at least one polymerization step may further include heating, UV-vis irradiation, incubation, or plasma exposure. According to some embodiments, heating of the IEM associated with the PL may include hot-pressing, lamination, co-extrusion, or any combination thereof.

[0048] According to some embodiments, a technique for applying the PL and / or the IEM is selected from: dip-coating, spin-coating, spray-coating, layer-by-layer deposition, vapor deposition, and any combination thereof.

[0049] Certain embodiments of the present disclosure may include some, all, or none of the above advantages. One or more technical advantages may be readily apparent to those skilled in the art from the figures, descriptions and claims included herein. Moreover, while specific advantages have been enumerated above, various embodiments may include all, some or none of the enumerated advantages.

[0050] In addition to the exemplary aspects and embodiments described above, further aspects and embodiments will become apparent by reference to the figures and by study of the following detailed descriptions.

[0051] BRIEF DESCRIPTION OF THE FIGURES

[0052] Some embodiments of the disclosure are described herein with reference to the accompanying figures. The description, together with the figures, makes apparent to a person having ordinary skill in the art how some embodiments may be practiced. The figures are for the purpose of illustrative description and no attempt is made to show structural details of an embodiment in more detail than is necessary for a fundamental understanding of the disclosure. For the sake of clarity, some objects depicted in the figures are not to scale.

[0053] In the figures:

[0054] FIGURE 1 - a schematic illustration of an electrochemical system including a protective layer (PL) associated with a separation membrane, according to some embodiments;

[0055] FIGURE 2 - a flowchart of steps of a method for purification / cleaning / treatment of pollutantcontaining solution and / or production of H2, according to some embodiments;

[0056] FIGURE 3 - a flowchart of steps of a method for producing a protected IEM for use in an electrochemical system, according to some embodiments;

[0057] FIGURE 4 - a line graph showing an increase of CI2 concentration in a catholyte during operation of electrochemical systems including (black trace) or excluding (grey trace) a PL; FIGURE 5 - a line graph showing a reduction of ammonia concentration in an anolyte during operation of a system excluding a PL; and

[0058] FIGURE 6 - a line graph showing a reduction of ammonia concentration in an anolyte during operation of a system including a PL.

[0059] DETAILED DESCRIPTION

[0060] In the following description, various aspects of the disclosure will be described. For the purpose of explanation, specific configurations and details are set forth in order to provide a thorough understanding of the different aspects of the disclosure. However, it will also be apparent to one skilled in the art that the disclosure may be practiced without specific details being presented herein. Furthermore, well-known features may be omitted or simplified in order not to obscure the disclosure.

[0061] Prior to setting forth the present subject matter in detail, it may be helpful to provide definitions of certain terms to be used herein. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as is commonly understood by one of skill in the art to which this subject matter pertains. The following definitions are provided for clarity.

[0062] The term "a" or "an" as used herein includes the singular and the plural, unless specifically stated otherwise. Therefore, the terms "a," "an", "at least one", or “at least two” can be used interchangeably in this application.

[0063] As used herein, the verb "comprise" as is used in this description and in the claims and its conjugations are used in its non-limiting sense to mean that items following the word are included, but items not specifically mentioned are not excluded.

[0064] As used herein, the term "about" when used in connection with a numerical value includes ±10% from the indicated value. In addition, all ranges directed to the same component or property herein are inclusive of the endpoints, are independently combinable, and include all intermediate points and ranges. It is understood that where a parameter range is provided, all integers within that range, and tenths thereof, are also provided by the invention. As used herein, in accordance with some embodiments, the term "pollutant" refers to a substance, molecule, polymer, compound, or salt contaminant that is present in a solution, (such as water) or the atmosphere, and may be harmful to humans, animals or the environment or is targeted to be removed from the solution and / or atmosphere.

[0065] As used herein, in accordance with some embodiments, the term "initial reactant" refers to a substance, molecule, polymer, compound, or salt that enters (e.g. introduced or present) into an anolyte compartment and is altered / changed in the course of an electrochemical reaction.

[0066] As used herein, in accordance with some embodiments, the terms “corrosive intermediate reactant”, “intermediate oxidative reactant”, and “intermediate byproduct” may interchangeably be used and refer to a product that is formed by the electrochemical oxidation of an initial reactant. In some embodiments, the “corrosive intermediate reactant” may oxidize or partially oxidize a pollutant. In addition, the ‘corrosive intermediate reactant’ may be corrosive in general, and specifically towards the ion exchange membrane (IEM).

[0067] As used herein, in accordance with some embodiments, the term "non-pollutant" refers to an entity (substance, molecule, polymer, compound, or salt) that is produced during the purification / treatment or separation process, wherein the non-pollutant entity is essentially not considered harmful to organisms (such as human or animals) or the environment. The non- pollutant product may be produced in a certain stoichiometric relationship with respect to the pollutant. In some embodiments, a pollutant entity may be converted to one or more non- pollutant entities during oxidation (e.g., indirect electro-oxidation) or the purification process.

[0068] As used herein, in accordance with some embodiments, the term "ion exchange membrane (IEM)" refers to a semipermeable membrane in which an ionic functionality is fixed to the backbone of the membrane. The ionic species enable the concentration, separation, transfer / transport, or exclusion of ionic species from a fluid. “Anion exchange membrane” (AEM), in accordance with some embodiments, is a membrane that has positively charged functional groups, the membrane allows the transport of anions while rejecting cations. “Cation exchange membrane” (CEM), in accordance with some embodiments, is a membrane that has negatively charged functional groups, the membrane allows the transport of cations while rejecting anions. As used herein, in accordance with some embodiments, the term "protective layer” (PL) refers to a physical layer that is associated with one or more faces of a membrane (such as, an IEM), and is configured to at least partially protect / shield the membrane from (direct) contact with corrosive chemicals (e.g., corrosive intermediate reactant). In some embodiments, the PL is configured to at least partially protect / shield an IEM from corrosive chemicals present within the anolyte compartment (e.g., in a pollutant-containing solution).

[0069] According to some embodiments, the PL is inert. As used herein, the term “inert” is directed to being chemically inactive or unreactive. In some embodiments, the PL is inert and does not react with chemical entities present in the system, such as, for example, entities present in the anolyte / catholyte. In some embodiments, the PL, therefore, does not essentially change its physical and / or chemical properties due to chemical interactions during a purification / treatment process.

[0070] As used herein, in accordance with some embodiments, the term "pollutant-containing solution" refers to a solution that contains a pollutant of any kind that one wishes to eliminate, convert, alter, or reduce.

[0071] As used herein, in accordance with some embodiments, the term "electro-oxidation", is interchangeably termed as “electrochemical oxidation” and refers to an anodic oxidation of an initial reactant, which in turn transforms into a corrosive intermediate reactant.

[0072] As used herein, in accordance with some embodiments, the term "indirect electrochemical oxidation" refers to a non-electrochemical oxidation of a pollutant by a corrosive intermediate reactant.

[0073] As used herein, in accordance with some embodiments, the term "electrically passive polymer" refers to a polymer that is essentially not charged, not conductive, and / or non-ionic.

[0074] As used herein, in accordance with some embodiments, the term "porous polymer" refers to a polymer having pores in a size range corresponding to the porosity of micro- or ultra- filtration membrane, as detailed herein.

[0075] As used herein, in accordance with some embodiments, the term "ammonia", which is in a gas form (i.e., NH3), is used interchangeably with the term “ammonium”, which is a protonated, water-solubilized salt form of ammonia (i.e., NH4+). According to some embodiments, there is provided herein an advantageous electrochemical system for purification of a pollutant-containing solution and optional production of H2, wherein the electrochemical system includes: at least two liquid compartments, including an anolyte compartment configured to hold a solution; and a catholyte compartment; wherein the liquid compartments are separated by an ion exchange membrane (IEM), which is associated with at least one protective layer (PL), preferably facing the anolyte compartment, such that, upon applying an electric field, initial reactant(s) in the anolyte compartment, are electrochemically oxidized into corrosive intermediate reactants, said intermediate reactants are capable of reacting with one or more pollutant species in the solution, to convert said pollutant species into a non-pollutant species(s), thereby purifying the solution.

[0076] Reference is now made to FIG. 1, which schematically illustrates an electrochemical system including a membrane with a protective layer, according to some embodiments. As shown in FIG. 1, system 100 includes an anolyte compartment 101 and a catholyte compartment 102, which includes an anode 103 and a cathode 104, respectively. The two compartments are separated by an ion exchange membrane (IEM) 105 associated with at least one protective layer (PL) 106, which, in the example shown in FIG. 1 is facing the anolyte compartment. The PL 106 is configured to at least partially prevent corrosive intermediate reactant(s) (shown as exemplary entities as CIO" and HC1O in FIG. 1), from reaching / contacting the IEM 105 from the anolyte compartment side 101. Pollutants (which are exemplified in FIG. 1 as NH3) are converted to non-pollutant species (exemplified as N2 gas in FIG. 1). At the catholyte compartment 102, an electrolysis reaction may take place to result in the production of H2 gas, as depicted in FIG. 1. In a case where an anion exchange membrane (AEM) is used, such as exemplified in FIG. 1 in 105, only anions can transfer through the membrane (exemplified as OH" ion in FIG. 1).

[0077] According to some embodiments, advantageously, the at least one PL may be two or more PLs. In some embodiments, the two PLs may be arranged parallel to each other from a single side of the membrane. In some embodiments, the two PLs may be arranged on the same surface plane from a single side of the membrane. In some embodiments, the two PLs may be arranged on the same surface plane continuously or non-continuously, from the same side of the membrane.

[0078] According to some embodiments, advantageously, the at least one PL enables the passage of fluids (such as water) and specific ions via the membrane (such as an IEM), while limiting contact of corrosive species with the membrane. According to some embodiments, the limited contact protects the membrane from damage and can thus at least partially prevent or reduce deterioration of the membrane. According to some embodiments, the at least one PL may thus extend the lifespan of a membrane in general, and the lifespan of the IEM specifically, as compared to IEM lacking the PL.

[0079] According to some embodiments, the at least one PL is configured to limit contact of the corrosive intermediate reactant with the IEM. According to some embodiments, the at least one PL is configured to limit contact of the corrosive intermediate reactant with the IEM while allowing passage of water and specific ions through the IEM.

[0080] In some embodiments, the PL is electrically passive. In some embodiments, the PL is chemically inert.

[0081] According to some embodiments, the PL is functionally and / or physically associated with one or both surfaces (faces) of the membrane.

[0082] In some embodiments, the PL may be attached to the membrane, glued to the membrane, adhered to the membrane, laminated to the membrane, pressed to the membrane, cover the membrane, and the like, or any combinations thereof.

[0083] In some embodiments, the PL may be directly contact the membrane, or in some instances, be spaced from the membrane surface by about 0.5-100 pm.

[0084] In some embodiments, the PL may be added as coating or impregnation to the surface of the membrane.

[0085] In some embodiments, one or both faces (sides / surfaces) of the membrane may be associated with a PL. In some embodiments, the PL associated with the two sides may be similar, identical, or different between the faces of the membrane.

[0086] According to some embodiments, the at least one PL may have a thickness of about 1 - 500 pm, or any subranges thereof, such as, for example, about 5-400 pm, about 200-400 pm, about 10-300 pm, about 20-200 pm, or about 30-150 pm. Each possibility is a separate embodiment. According to some embodiments, the at least one PL includes a porous polymer. According to some embodiments, the at least one PL has an average pore size in the range of about 0.001-10 pm. According to some embodiments, the average pore size is in the range of microfiltration membrane, i.e., about 0.03-10 pm. According to some embodiments, the average pore size is about 0.03-1 pm, about 1-3 pm, about 3-6 pm, or about 6-10 pm. Each possibility is a separate embodiment. According to some embodiments, the average pore size is in the range of ultrafiltration membrane, i.e., about 0.001-0.1 pm. According to some embodiments, the average pore size is about 0.001-0.005 pm, about 0.005-0.01 pm, about 0.01- 0.05 pm, or about 0.05-0.1 pm. Each possibility is a separate embodiment. According to some embodiments, the pore size includes pores in the range of both ultrafiltration and microfiltration membranes. Advantageously, and according to some embodiments, the porosity as disclosed herein allows a penetration of only water and selective ions / molecules while limiting access to the IEM. According to some embodiments, the porosity of the PL facilitates physical trapping of intermediate corrosive reactants. According to some embodiments, the porosity of the PL facilitates physical trapping of intermediate corrosive reactants within the pores. In some embodiments, (intermediate) corrosive reactants are adsorbed onto the PL from the side of the anolyte compartment. In some embodiments, (intermediate) corrosive reactants are adsorbed onto the PL and their access towards the IEM is reduced. In some embodiments, the PL prevents / reduces interaction between (intermediate) corrosive reactants and the IEM.

[0087] According to some embodiments, the at least one PL includes an electrically passive polymer. According to some embodiments, the electrically passive porous polymer is selected from, but not limited to polyolefin, polyethylene, polypropylene, polyester, polystyrene, porous polyolefin matrix, polymethylmethacrylate, polyvinylchloride (PVC), polyamide, polyvinylidendifluoride (PVDF), co-polymer based on the natural or synthetic rubber or thermoplastic elastomer, polytetrafluorethylene (Teflon), polyethersulfone (PES), their derivatives, and any co-polymer thereof. Each possibility is a separate embodiment.

[0088] According to some embodiments, the electrically passive polymer is hydrophilic. According to some embodiments, the electrically passive polymer is hydrophobic.

[0089] According to some embodiments, the electrically passive polymer is further crosslinked. According to some embodiments, the electrically passive polymer is highly crosslinked. According to some embodiments, the electrically passive polymer is highly dense. In some embodiments, the high density of the polymer increases its capacity towards corrosive intermediate reactants.

[0090] According to some embodiments, the at least one PL may be further impregnated or doped with conductive elements. According to some embodiments, the conductive elements may be selected from, but not limited to, metal-containing nanoparticles, metal-containing layer, conductive carbonaceous particulate, derivatives thereof, or any combination thereof. Each possibility is a separate embodiment. According to some embodiments, the conductive element impregnated or doped PL may further allow adjusting or determining the IEM-PL assembly electrical properties, such as resistance level.

[0091] According to some embodiments, one or more additional electrically passive layers can be added to the at least one PL. According to some embodiments, the additional layer may be selected from but not limited to, an activated carbon layer, a porous inorganic layer, a gel layer, a polymer layer, and any combination thereof. Each possibility is a separate embodiment.

[0092] According to some embodiments, the at least one PL can advantageously extend the lifespan and / or robustness of the IEM. In some embodiments, the at least one PL may extend the lifespan of the IEM by at least about 2-fold, for example, by at least about 5-fold, at least about 10-fold, at least about 15-fold, at least about 20-fold, at least about 25-fold, at least about 30-fold, at least about 35 -fold, or at least about 40-fold, as compared to IEM lacking the PL. Each possibility is a separate embodiment.

[0093] According to some embodiments, the at least one PL may serve as a physical barrier for chemical entities from contacting, chemically attacking, or interacting with the membrane. According to some embodiments, the at least one PL may serve as a physical barrier for chemical entities originating from the electrochemical process, non-electrochemical process, and / or indirect electrochemical process. According to some embodiments, the at least one PL may serve as a physical barrier for a pollutant, initial reactant, or, preferably from a corrosive intermediate reactant. Each possibility is a separate embodiment.

[0094] Advantageously, and according to some embodiments, the at least one PL may at least partially protect the IEM from deterioration. According to some embodiments, the at least one PL may prevent chemical entities present in wastewater from reaching the surface / face of a membrane. According to some embodiments, the at least one PL may prevent chemical entities present in wastewater from reaching the IEM. According to some embodiments, the at least one PL prevents corrosive intermediate reactants from reaching the IEM. According to some embodiments, the at least one PL prevents active chloro and / or chloramine species, for example, OCT, H0C1, Ch, NH2CI, NHCI2, or NCI3, from reaching the IEM. Each possibility is a separate embodiment.

[0095] According to some embodiments, advantageously, the at least one PL may aid in preventing corrosive intermediate reactants from passing into another compartment separated by the membrane. According to some exemplary embodiments, the at least one PL may aid in preventing corrosive intermediate reactants from passing into the catholyte compartment.

[0096] Surprisingly, and according to some embodiments, as exemplified herein below, the IEM associated with the PL exhibits an electrical resistance that is no more than about 15% higher, as compared to the IEM lacking PL, for example, less than about 12% higher, less than about 10% higher, or preferably less than about 8% higher, as compared to the IEM lacking PL. Each possibility is a separate embodiment. Advantageously, and according to some embodiments, the electrical resistance is not high enough to substantially reduce the performance of the IEM.

[0097] According to some embodiments, the IEM may be selected from a cation exchange membrane (CEM), an anion exchange membrane (AEM), and a bipolar membrane (BPM). Each possibility is a separate embodiment.

[0098] According to some embodiments, the pollutant-containing solution may be selected from but not limited to, wastewater, industrial waste stream, drinking water, biological fluid(s), alkaline solution, acidic solution, alcohol, salted water, cell culture medium, food / feed- production related medium, chemical industry related medium, ion exchange brines, membrane filtration concentrate, and any combination thereof. Each possibility is a separate embodiment. According to some embodiments, the solution may be wastewater.

[0099] According to some embodiments, biological fluid(s) may include, for example, but is not limited to, blood, urine, saliva, and the like. Each possibility is a separate embodiment.

[0100] According to some embodiments, the pollutant-containing solution may originate from solid waste. According to some embodiments, the pollutant-containing solution originates from the total Kjeldahl nitrogen (TKN) workup method performed on the solid waste. According to some embodiments, the TKN method is based on the wet oxidation of soil organic matter and botanical materials, and the conversion of organic nitrogen byproducts to the ammonium pollutant solubilized in water.

[0101] According to some embodiments, the purification / treatment system may include a plurality of anolyte and catholyte compartment(s), each separated by an ion exchange membrane (IEM), at least some of the membranes are associated with at least one protective layer (PL) facing the anolyte compartment.

[0102] According to some embodiments, an anode includes an oxidizing catalyst. According to some embodiments, the oxidizing catalyst is selected from but not limited to Ir, Ru, Ti, Pd, Sb, Sn, Fe, derivatives thereof, oxides thereof, and any combination thereof. Each possibility is a separate embodiment. According to some embodiments, the oxidizing catalyst is selected from, but not limited to, RuCh, IrCh, and TiCh Each possibility is a separate embodiment.

[0103] According to some embodiments, the initial reactant includes ions or compounds selected from: As, Hg, Cd, Zn, Ag, Cu, Fe, Cr, Ni, Pd, Pt, Sn, Sb, Ti, Ru, Ir, chloride ions (Cl’ ), chlorite ions (CICh'), sulfate ions (SCh2'), phosphate species (H3PO4, EbPOri, HPCL2', PCU3' ), peroxymonosulfate ions (HSCh'), peroxydisulfate ions (S2O82), derivatives thereof, and any combination thereof. Each possibility is a separate embodiment.

[0104] According to some embodiments, the oxidation of a pollutant is facilitated by a reaction with a higher oxide compound formed and / or degraded from the anode. According to some embodiments, the compound includes, but is not limited to, metal oxides of RuCh and / or IrCh, or a mixture thereof. Each possibility is a separate embodiment.

[0105] According to some embodiments, the corrosive intermediate reactant includes oxidized ions or compounds selected from: As, Hg, Cd, Zn, Ag, Cu, Fe, Cr, Ni, Pd, Pt, Ru, Ir, Sn, Sb, Ti chlorine radicals (Cl and Ch'), active chlorine species (Ch, HOCT, OC1'), chloramines (NCh,NH2Cl, NHCh), chlorate ions (CIOs'), chlorine dioxide (CIO2, C1O2'), persulfates S20s2' , peroxy diphosphate (P20s4'), peroxymonophosphoric acid (H3PO5), hydroxyl radicals (OH ), peroxide (e.g., H2O2), ozone (O3), sulfate radical (SOC), derivatives thereof, and any combination thereof. Each possibility is a separate embodiment.

[0106] According to some embodiments, the corrosive intermediate reactant (e.g., Ch, HOCT , OC1') is produced at the anode via an electro-oxidation of an initial reactant (e.g., Cl'). According to some embodiments, the initial reactant (e.g., Cl') undergoes electro-chlorination. According to some embodiments, the pollutant undergoes indirect electrochemical oxidation. According to some embodiments, the pollutant undergoes chloro-amination.

[0107] According to some embodiments, reactions utilizing the initial reactant undergo via, but are not limited to, reaction (1), the reactant is labeled in bold:

[0108] (1) 2Cl~ -> Cl2+ 2e~

[0109] According to some embodiments, reactions towards the production of the corrosive intermediate reactant occur via, but are not limited to, any of the reactions (1-6), corrosive intermediate reactant is labeled in bold:

[0110] According to some embodiments, reactions utilizing the corrosive intermediate reactant may undergo via, but are not limited to, any of the reactions (2-6), corrosive intermediate reactant is labeled in bold:

[0111] According to some embodiments, reactions for the production of the non-pollutant specie(s) may undergo via, but are not limited to, reaction (6), non-pollutant is labeled in bold:

[0112] (6) NCl2+ NHCl2+ 0H~ N2+ 20Cl~ + 3Cl~ + H20

[0113] According to some embodiments, reactions utilizing the pollutant undergo via, but are not limited to, reaction (2), pollutant is labeled in bold: According to some embodiments, the pollutant may be selected from, but is not limited to, an inorganic compound, organic molecule, biological species, industrial chemical compounds, and any combination thereof. Each possibility is a separate embodiment.

[0114] According to some embodiments, the inorganic compound pollutant may be selected from, but is not limited to: ammoniacal nitrogen (NH3 and NH4+), urea, methyldiethanolamine, sulfides, metal salts, and any combination thereof. Each possibility is a separate embodiment. According to some embodiments, the inorganic compound pollutant is NH3.

[0115] According to some embodiments, the organic molecule pollutant may be selected from, but is not limited to, an amino acid, lipid, carbohydrate, protein, and any combination thereof. Each possibility is a separate embodiment.

[0116] According to some embodiments, the biological specie pollutant may be selected from, but is not limited to, a cell, bacteria, virus, fungus, and any combination thereof. Each possibility is a separate embodiment.

[0117] According to some embodiments, the industrial chemical compounds pollutant may be selected from, but is not limited to: pharmaceutical, dye, polymer, halogenated polymer, halogenated compound, and any combination thereof. Each possibility is a separate embodiment. According to some embodiments, the halogenated compound or polymer is per- or polyfluorinated- substance (PF AS).

[0118] According to some embodiments, the initial reactant includes chloride, the pollutant includes NH3, the corrosive intermediate reactant includes chloramine, and the non-pollutant product includes N2. According to some embodiments, the initial reactant includes chloride, the pollutant includes NH3, and the non-pollutant product includes N2.

[0119] According to some embodiments, the initial reactant includes chloride, the pollutant includes NH3, the corrosive intermediate reactant includes chlorine, and the non-pollutant product includes N2.

[0120] According to some embodiments, the initial reactant includes chloride, the pollutant includes NH3, the corrosive intermediate reactant includes hypochlorite, and the non-pollutant product includes N2. According to some embodiments, the at least one PL can be used with a dialysis membrane, an ultrafiltration membrane, nanofiltration membrane. Each possibility is a separate embodiment.

[0121] According to some embodiments, there is provided herein a method for purification / treatment of pollutant-containing solution and / or production of H2, the method includes: providing an electrochemical system as disclosed herein, which includes at least one IEM associated with a PL; introducing a pollutant-containing solution into the anolyte compartment; applying an electrical field; and generating purified solution in the anolyte and / or producing H2 in the catholyte compartment.

[0122] Reference is now made to FIG. 2, which schematically illustrates a flowchart of a method for the purification / treatment of pollutant-containing solution and / or production of H2, while providing protection to the separation membrane, according to some embodiments. As shown in FIG. 2, the purification / treatment method 200 includes, in step 210, providing an electrochemical system. The electrochemical system may be any type of electrochemical system, which includes an IEM associated with a protective layer as detailed herein. In some exemplary embodiments, the system may be a system as illustrated in FIG. 1. In step 220, a pollutant-containing solution is introduced into the anolyte compartment. The pollutant-rich solution may include, for example, sewer, wastewater, industrial waste stream, drinking water, biological fluid(s), and the like, as detailed above. In optional step 230, an initial reactant is added and / or generated in the anolyte compartment, e.g., NaCl. In step 240, a desired electric field is applied. The electric field parameters (such as current or voltage) may be predetermined, constant, or adjusted in accordance with the characteristics of the system, reactants, solutions, etc. In step 250, a purified / cleaner / pollutant-reduced solution is generated in an anolyte compartment of the system, and / or H2 is produced in the catholyte compartment of the system.

[0123] According to some embodiments, the system or method further facilitates a reduction in the pollutant level in the pollutant-containing solution. According to some embodiments, the system or method further facilitates a reduction in the NH3 pollutant level in the pollutantcontaining solution. In some embodiments, the system or method further facilitates a complete reduction of the NH3 pollutant level in the pollutant-containing solution. In some embodiments, the method or system produces nitrogen gas as a non-pollutant product. Advantageously, according to some embodiments, the production of H2 may occur simultaneously with the purification of the pollutant-containing solution.

[0124] According to some embodiments, the production of H2 may be facilitated via hydrogen evolution reaction (HER). According to some embodiments, the production of H2 may occur via any one or both of the following reactions: (10) 2H++ 2e~ -> H2, or (11) 2H2O + 4e“ -> 2H2+ 4OH~. According to some embodiments, the production of H2 occurs via (10). According to some embodiments, the production of H2 occurs under acidic conditions. According to some embodiments, the production of H2 occurs via (1) in acidic conditions.

[0125] According to some embodiments, the production of the H2 is in an efficiency of about 0.2-1 L / min, such as, for example, about 0.2 L / min.

[0126] According to some embodiments, the initial reactant is present in a given pollutantcontaining solution and / or supplemented to the given pollutant-containing solution. According to some embodiments, the initial reactant can be introduced into the compartment in different forms, including gas, solid, or liquid. Each possibility is a separate embodiment.

[0127] According to some embodiments, the pollutant-containing solution is supplemented with an additional electrolyte. According to some embodiments, the additional electrolyte is a liquid solution or a semi-solid / solid polymeric electrolyte. Each possibility is a separate embodiment.

[0128] According to some embodiments, the PL facilitates the application of the purification method over a wide range of temperatures. According to some embodiments, the applicable temperature of operation may be in the range of about 4-45 °C, for example, 10-45 °C, 4-25 °C, or 15-35 °C. Each possibility is a separate embodiment.

[0129] According to some embodiments, the PL facilitates the application of the purification method over a wide range of pH conditions. According to some embodiments, the applicable pH of operation is about 6-12 at the anolyte, for example, pH 6-10, pH 8-12, or pH 7-11. Each possibility is a separate embodiment. In some embodiments, the PL protects the membrane, e.g., IEM, against acidic species. According to some embodiments, the efficiency of pollutant removal / conversion in a system in which the IEM is associated with a PL, is higher as compared to a system lacking a PL.

[0130] According to some embodiments, the catholyte is devoid of a solution. According to some embodiments, the catholyte is essentially dry at the beginning of the operation of the system (i.e., at the beginning of the purification process).

[0131] According to some embodiments, the pollutant-containing solution may be introduced into the anolyte in pulses. According to some embodiments, the pollutant-containing solution may be introduced into the anolyte in intervals. According to some embodiments, the pollutantcontaining solution may be introduced into the anolyte continuously. In some embodiments, the cleaned / purified / treated solution may be collected from the anolyte compartment at a rate suitable for the introduction rate of the pollutant-containing solution. In some embodiments, the cleaned / purified / treated solution may be collected from the anolyte compartment at the same rate as that of introducing the pollutant-containing solution.

[0132] According to some embodiments, the purified / treated solution may be collected from the anolyte or catholyte compartments. According to some embodiments, the purified / treated solution is preferably collected from the anolyte compartment.

[0133] According to some embodiments, the method for treatment / purification of a pollutantcontaining solution may be used in various applications, such as, but not limited to: microelectronics, chemical industry, agricultural, irrigation water, wine, food and beverages preparations, drinking water, and desalination water. Each possibility is a separate embodiment.

[0134] According to some embodiments, the treatment / purification methods disclosed herein can further be used for sensing or monitoring contaminant content / presence in the solution and / or contaminant removal / conversion efficiency.

[0135] According to some embodiments, the applied electric field may be generated by a power supply having an energy source selected from, but not limited to, solar, hydropower, biomass, gas, petroleum, geothermal, coal, nuclear, heat, fuel, uranium, gravitational, and any combination thereof. Each possibility is a separate embodiment. According to some embodiments, the applied electric field may be generated by a power supply having a combination of energy sources. According to some embodiments, the applied electric field may be generated by a power supply utilizing hydrogen gas as an energy source. According to some embodiments, the hydrogen gas may be generated by the electrochemical system provided herein. According to some embodiments, the system disclosed herein may thus be self- sustainable. According to some embodiments, the system disclosed herein is based on renewable circular energy.

[0136] According to some embodiments, a purification / treatment process may include a plurality of purification systems. In some embodiments, the plurality of the purification systems may function in parallel. In some embodiments, the plurality of the purification systems may function serially. In some embodiments, the plurality of the purification systems may function by a combination of parallel and serial functions.

[0137] According to some embodiments, the pollutant-containing solution may be pretreated by one or more additional steps and / or methods.

[0138] According to some embodiments, the method for purification of pollutant-containing solution provided herein may be used solely or in addition to a method such as, but not limited to: adsorption, ion exchange, chemical oxidation, chemical reduction, membrane filtration, biological treatment, chemical precipitation, stripping, electro-coagulation, and other electrochemical processes. Each possibility is a separate embodiment.

[0139] According to some embodiments, the solution containing pollutants may include total hardness ions (specifically Ca2+and Mg2+), which can affect the system's overall performance by precipitation on the cathode side, i.e. scaling, and thus modifying the conductivity of the ion exchange membrane. In some embodiments, in instances where the protective layer (PL) possesses a pore diameter of about 0.001-0.01 pm (i.e., a nanofiltration membrane), divalent ions like Ca2+and Mg2+can be repelled / blocked by the PL, thereby protecting the system from the impact of these ions.

[0140] Advantageously, and according to some embodiments, the method for purification / treatment of pollutant-containing solution provided herein may be followed by an IEM regeneration / cleaning treatment that is at least about 1.1-2 times faster, as compared to a system lacking PL. In some embodiments, the PL may be conveniently replaced with a new or cleaner PL. According to some embodiments, the method for purification / treatment of pollutantcontaining solution provided herein may be followed by an IEM regeneration / cleaning treatment that is devoid of an alkaline solution and / or acidic solution.

[0141] There is provided herein, in accordance with some embodiments, a method of producing a protected IEM for use in an electrochemical system, the method including: providing a flat surface; applying a PL layer; applying an IEM layer, to thereby produce the protected IEM.

[0142] Reference is now made to FIG. 3, which schematically illustrates a flowchart of steps of a method for producing a protected IEM for use in an electrochemical system, according to some embodiments. As shown in FIG. 3, manufacturing method 300 includes, in step 310, providing a flat surface. In step 320, a suitable PL layer is applied onto the surface. The PL material may be selected from, but not limited to: PVDF, PES, and PE. The application of the PL may include, for example, but not limited to: dip-coating, spin-coating, spray-coating, layer- by-layer deposition, vapor deposition, injecting, printing. In some embodiments, the PL is applied as a monomer. In some embodiments, the application of the monomer is followed by polymerization and / or cross-linking steps. In some embodiments, the PL is applied as a polymer.

[0143] According to some embodiments, the application of the PL (step 320) is performed before the application of the IEM (step 330). According to some embodiments, the application of the PL (step 320) is performed after the application of the IEM (step 330).

[0144] In step 330, an IEM layer is applied. The application of the membrane may include, for example, but not limited to, dip-coating, spin-coating, spray-coating, layer-by-layer deposition, vapor deposition, injecting, and printing. In some embodiments, the IEM is applied as a monomer. In some embodiments, the applied monomer is a cationic monomer or an anionic monomer, in accordance with the charge of the membrane (CEM or AEM). In some embodiments, the application of the monomer is followed by polymerization and / or crosslinking steps. In some embodiments, the IEM is applied as a polymer.

[0145] In step 340, a protected IEM is thereby obtained / produced. According to some embodiments, the flat surface may be a plate made from a material selected from: glass, metal, plastic, silicon, ceramics, wood, and any combination thereof. Each possibility is a separate embodiment.

[0146] According to some embodiments, applying the PL may be performed prior to applying the IEM. According to some embodiments, applying the IEM may be performed prior to applying the PL.

[0147] According to some embodiments, the application technique may be selected from, but not limited to, dip-coating, spin-coating, spray-coating, layer-by-layer deposition, vapor deposition, and any combination thereof. Each possibility is a separate embodiment.

[0148] According to some embodiments, the IEM and / or PL may be applied as a monomer. According to some embodiments, the monomer may include an ion exchange ionomer, including an anionic ionomer and / or cationic monomer. Each possibility is a separate embodiment.

[0149] According to some embodiments, the method may further include at least one polymerization step. According to some embodiments, the polymerization step is performed after applying the PL and / or the IEM. Each possibility is a separate embodiment.

[0150] According to some embodiments, the at least one polymerization step may further include cross-linking.

[0151] According to some embodiments, the at least one polymerization step further includes a technique selected from, but is not limited to, heating, UV-vis irradiation, incubation, and plasma exposure. Each possibility is a separate embodiment. According to some embodiments, the heating of the IEM-PL assembly includes, but is not limited to, hot-pressing, lamination, co-extrusion, or any combination thereof. Each possibility is a separate embodiment.

[0152] According to some embodiments, the method may further include adding an ingredient selected from the group consisting of an initiator, cross-linker, catalyst, and a solvent. Each possibility is a separate embodiment.

[0153] According to some embodiments, the IEM includes a polycation that includes such side chains as, but not limited to: amino or hydrocarbon side chains and / or a polyanion consisting of sulfonic or carboxylic. Each possibility is a separate embodiment. In some embodiments, the production method may include providing a membrane (precast or premade) and associating a PL (precast or premade) with one or both faces of the membrane, for example, by adhering, gluing, laminating the membrane with the PL under suitable conditions, to thereby obtain a protected membrane.

[0154] According to some embodiments, the preparation may include providing an IEM and laminating the IEM with a PL on one or both faces of the membrane.

[0155] In some embodiments, the PL may be integrally formed with the membrane.

[0156] The following examples are presented in order to more fully illustrate some embodiments of the invention. They should, in no way be construed, however, as limiting the broad scope of the invention. One skilled in the art can readily devise many variations and modifications of the principles disclosed herein without departing from the scope of the invention.

[0157] EXAMPLES

[0158] Example 1 - Preparation of an anion exchange membrane-protective layer (AEM-PL) assembly

[0159] An anion exchange ionomer in a concentration of 10% in Alcohol: Ketone was dispersed via sonication. A volume of 20 mL of the resulting solution was spray-coated over a flat substrate of glass plate having a size of 14 cm x 14 cm followed by drying in an oven at 90°C. The coated substrate was then covered with a polymeric membrane of Poly ethersulfone (PES). The layered assembly was laminated together . Curing of the membrane was performed in an alkaline solution of KOH (IM) to obtain a free-standing bilayer of AEM-PL membrane assembly, where the thickness of the PL was 120 pm and the thickness of the AEM was 75 pm.

[0160] Example 2 - The effect of the protecting layer on the electrical resistance of the membrane

[0161] An assembly of PES-AEM having a PL thickness of 120 pm and which was prepared according to Example 1, was examined by using a 4-probe membrane cell. A 4-probe membrane cell is an electrochemical device used to measure the resistance of a thin layer, by forcing current between two outer probes and measuring the voltage between two inner probes separated by the thin layer.

[0162] A solution of NaCl (6 M) was circulated through both the anodic and cathodic compartments. Using a potentiostat, a steady current was applied for 60 seconds to ensure stable voltage measurement, followed by an incremental increase in current by 10 mA. The experiment was conducted on three setups: the cell without a membrane, with an AEM membrane, and with an AEM+PL assembly. The resulting slope of the I-V curve line represents the resistance, and the results are represented in Table 1.

[0163] Table 1 Configuration J inti No membrane 0.78

[0164] AEM . 0.93. ]

[0165] ["AEM+PL . . 1

[0166] Example 3 - Deterioration of an anion exchange (AEM) membrane with and without a protective layer (PL)

[0167] An assembly of PES-AEM, prepared according to Example 1 was examined by using the 4-probe membrane cell. The cell was utilized to demonstrate the extension of membrane lifespan when employing PL in challenging environmental conditions. In this study, a solution containing CT in a concentration of 35 gr / L (i.e. IM NaCl) was circulated through the two compartments while applying 0.3 Ampere on the cell. During the experiment, samples were taken from catholyte to analyze the presence of active chlorine (Ch), which was produced at the anode compartment. The detection of active chlorine at the cathode compartment indicated the deterioration of the membrane. It can be seen in FIG. 4 that the active chlorine passed the AEM into the catholyte after 50 min when AEM was not protected, but after 110 min when the AEM was protected with PL. Advantageously, as can be seen in this example, PL is configured to protect ion exchange membrane against corrosive reactant intermediates, such as active chlorine. Advantageously, when the IEM is protected with the PL, the IEM rupture is delayed or reduced. Ammonia removal by the anion exchange (AEM) membrane with and without a protective layer (PL)

[0168] The efficiency of both AEM alone and AEM+PL configurations was assessed for removing ammonia within the cell. A current density of 100 mA / cm2was applied between the two terminals. The cell operated with simulated wastewater containing CT in a concentration of 6 gr / L circulated through the anodic compartment, while water flowed through the cathodic compartment.

[0169] Utilizing AEM alone in the cell yielded a current efficiency of 52% and an energy consumption of 38 kWh / kgN. However, after 35 minutes of the experiment, the membrane ruptured, leading to the mixing of the anolyte and catholyte. Ammonia in a concentration of 200 mg / L was removed after this period, as can be seen in FIG. 5.

[0170] Implementing AEM+PL produced according to Example 1 resulted in a current efficiency of 49% and an energy consumption of 45 kWh / kgN. The cell operated for 15 hours before indicating signs of membrane rupture. Ammonia in a concentration of 730 mg / L was removed after 6.3 hours, as can be seen in FIG 6.

[0171] Advantageously, as can be seen in this example, operating the treatment / purification system, including an IEM protected / associated with the PL, enables to extend operation / purification / treatment duration by at least an order of magnitude, as compared to a system lacking the PL.

Claims

CLAIMS1. An electrochemical system for purification of a pollutant-containing solution and / or production of H2, the electrochemical system comprising: at least two liquid compartments, comprising an anolyte compartment configured to hold a solution, and a catholyte compartment; and an ion exchange membrane (IEM) separating the liquid compartments, said IEM is associated with at least one protective layer (PL) facing the anolyte compartment, wherein upon applying an electric field, initial reactant(s) in the anolyte compartment are electrochemically oxidized into corrosive intermediate reactants, said corrosive intermediate reactants are capable of reacting with one or more pollutant species in the solution, to convert said pollutant species into a non-pollutant species(s), thereby purifying the solution.

2. The electrochemical system according to claim 1, wherein the IEM is selected from a cation exchange membrane (CEM), an anion exchange membrane (AEM), and a bipolar membrane (BPM).

3. The electrochemical system according to any one of claims 1 and 2, wherein the at least one PL facilitates passage of water and specific ions, while limiting contact of the intermediate reactants with the IEM.

4. The electrochemical system according to any one of claims 1-3, wherein the purified solution is being collected from the anolyte compartment.

5. The electrochemical system according to any one of claims 1-4, wherein the at least one PL has a thickness of about 1 - 500 pm.

6. The electrochemical system according to any one of claims 1-5, wherein the at least one PL comprises a porous polymer.

7. The electrochemical system according to any one of claims 1-6, wherein the at least one PL comprises an electrically passive polymer.

8. The electrochemical system according to any one of claims 1-7, wherein the at least one PL has an average pore size in the range of about 0.001-10 pm.

9. The electrochemical system according to claim 8, wherein the average pore size is in the range of about 0.03-10 pm.

10. The electrochemical system according to claim 8, wherein the average pore size is in the range of about 0.001-0.1 pm.

11. The electrochemical system according to any one of claims 6 and 7, wherein the electrically passive porous polymer comprises polyethylene, polypropylene, polyester, polystyrene, polymethylmethacrylate, polyvinylchloride (PVC), polyamide, polyvinylidendifluoride (PVDF), co-polymer based on the natural or synthetic rubber or thermoplastic elastomer, polytetrafluorethylene (Teflon), polyethersulfone (PES), any derivative thereof, any co-polymer thereof, or any combination thereof.

12. The electrochemical system according to any one of claims 1-11, wherein the at least one PL is further impregnated or doped with conductive elements.

13. The electrochemical system according to any one of claims 1-12, wherein the system further facilitates a reduction of NH3 pollutant level in the pollutant-containing solution.

14. The electrochemical system according to any one of claims 1-13, wherein the pollutantcontaining solution comprises wastewater, industrial waste stream, drinking water, biological fluid(s), alkaline solution, acidic solution, alcohol, salted water, cell culture medium, food / feed-production related medium, chemical industry related medium, ion exchange brines, membrane filtration brines, or any combinations thereof.

15. The electrochemical system according to claim 14, wherein the solution is wastewater.

16. The electrochemical system according to any one of claims 1-15, wherein the system comprises a plurality of anolyte and catholyte compartment(s), each separated by an ion exchange membrane (IEM), associated with at least one protective layer (PL) facing the anolyte compartment.

17. The electrochemical system according to any one of claims 1-16, wherein an anode comprises an oxidizing catalyst.

18. The electrochemical system according to claim 17, wherein the oxidizing catalyst comprises Ir, Ru, Ni, Ti, Pd, Sb, Sn, and / or Fe.

19. The electrochemical system according to any one of claims 1-18, wherein the initial reactant comprises ions or compounds selected from: As, Hg, Cd, Zn, Ag, Cu, Fe, Cr, Ni, Pd, Pt, Sn, Sb, Ti, Ru, Ir, chloride ions, chlorite ions, sulfate ions, phosphate species, peroxymonosulfate ions, peroxy di sulfate ions, and derivatives thereof.

20. The electrochemical system according to any one of claims 1-19, wherein the corrosive intermediate reactant comprises oxidized ions or compounds selected from: As, Hg, Cd, Zn, Ag, Cu, Fe, Cr, Ni, Pd, Pt, Ru, Ir, Sn, Sb, Ti, chlorine radicals, active chlorine species, chloramines, chlorate ions, chlorine dioxide, persulfates S20s2', peroxydiphosphate, peroxymonophosphoric acid, hydroxyl radicals, peroxide, ozone, sulfate radical, derivatives thereof, and any combinations thereof.

21. The electrochemical system according to any one of claims 1-20, wherein the pollutant comprises inorganic compounds selected from ammoniacal nitrogen, urea, sulfides, metal salts, and any combination thereof.

22. The electrochemical system according to any one of claims 1-21, wherein the pollutant comprises organic molecules selected from: amino acids, lipids, carbohydrates, proteins, and any combination thereof.

23. The electrochemical system according to any one of claims 1-22, wherein the pollutant comprises biological species selected from: cells, bacteria, viruses, and fungi.

24. The electrochemical system according to any one of claims 1-23, wherein the pollutant comprises industrial chemical entities selected from: pharmaceuticals, dyes, polymers, and halogenated polymers and / or compounds.

25. The electrochemical system according to any one of claims 1-24, wherein the initial reactant comprises chloride, the pollutant comprises NH3, the corrosive intermediate reactant comprises chloramine, and the non-pollutant product comprises N2.

26. The electrochemical system according to any one of claims 1-25, wherein the at least one PL extends the lifespan of the IEM by at least about 2-fold, compared to an IEM which is not associated with the at least one PL.

27. A method for purification of pollutant-containing solution and / or production of H2, the method comprising;providing the electrochemical system according to any one of claims 1-26; introducing a pollutant-containing solution into the anolyte compartment; applying an electric field; and generating purified solution in the anolyte and / or producing H2 in the catholyte compartment.

28. The method according to claim 27, wherein introducing a pollutant-containing solution further comprises adding an initial reactant.

29. The method according to any one of claims 27-28, wherein the catholyte compartment is acidified / neutralized with an acid.

30. The method according to any one of claims 27-28, wherein the catholyte is devoid of a solution.

31. A method of producing the protected ion exchange membrane (IEM) of the electrochemical system of any one of claims 1-26, the method comprising: providing a flat surface; applying the protective layer (PL); applying an IEM layer; and thereby, producing the IEM associated with the PL.

32. The method according to claim 31, wherein applying the PL is performed prior to applying the IEM.

33. The method according to claim 32, wherein applying the IEM is performed prior to applying the PL.

34. The method according to any one of claims 31-33, wherein the IEM and / or the PL are applied as a polymer.

35. The method according to any one of claims 31-33, wherein the IEM and / or the PL are applied as a monomer.

36. The method according to claim 35, wherein the applied monomer of the IEM comprises an anionic and / or a cationic monomer.

37. The method according to any one of claims 31-36, further comprising at least one polymerization step.

38. The method according to claim 37, wherein the at least one polymerization step is performed after applying the PL and / or the IEM.

39. The method according to any one of claims 37 and 38, wherein the at least one polymerization step further comprises a cross-linking step.

40. The method according to any one of claims 37-39, wherein the at least one polymerization step comprises heating, UV-vis irradiation, incubation, or plasma exposure.

41. The method according to claim 40, wherein heating of the IEM associated with the PL comprises hot-pressing, lamination, co-extrusion, or any combination thereof.

42. The method according to any one of claims 31-41, wherein a technique for applying the PL and / or the IEM is selected from: dip-coating, spin-coating, spray-coating, layer- by-layer deposition, vapor deposition, and any combination thereof.

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