Oxidation-reduction system configured for water or wastewater treatment by removal of organic and inorganic pollutants, method for water or wastewater treatment, catalyst for heterogeneous catalytic ozonation and / or for heterogeneous catalytic reduction, and method for preparing thereof

Abstract

The invention refers to an oxidation-reduction system configured for water or wastewater treatment by removal of organic and inorganic pollutants comprising a catalytic oxidation multiphase reactor (1) in series with a catalytic reduction multiphase reactor (6), wherein at least one catalytic bed (2,7) comprises a macrostructured catalyst. The invention also refers to a catalyst for heterogeneous catalytic ozonation and / or for heterogeneous catalytic reduction comprising an active component selected from a group consisting of a metal, a metal oxide, or a carbon-based material supported on a macrostructured catalyst. The combined processes (catalytic ozonation and reduction) are able to remove emerging organic and inorganic (micro)pollutants more efficiently, promoting not only the degradation and ultimately mineralization of organic pollutants, but also the transformation of resulting inorganic subproducts into non-harmful substances.

Description

OXIDATION-REDUCTION SYSTEM CONFIGURED FOR WATER OR WASTEWATER TREATMENT BY REMOVAL OF ORGANIC AND INORGANIC POLLUTANTS, METHOD FOR WATER OR WASTEWATER TREATMENT, CATALYST FOR HETEROGENEOUS CATALYTIC OZONATION AND / OR FOR HETEROGENEOUS CATALYTIC REDUCTION, AND METHOD FOR PREPARING THEREOF

[0001] The present invention relates to the field of systems for treating water or wastewater by removing organic and inorganic pollutants, and to the related field of catalysts proper to be used in chemical processes regarding water treatment for the removal of organic and inorganic pollutants.

[0002] The presence of organic and inorganic micropollutants in water sources has emerged as a pressing environmental concern, posing significant challenges to conventional water treatment processes. These micropollutants encompass a wide range of substances, including organic compounds, for example, pharmaceuticals, or pesticides; inorganic compounds, for example, heavy metals, bromate, nitrate, nitrite, or perchlorate; besides other micropollutants, for example, those derived from personal care products. These micropollutants are often found in trace concentrations but can have adverse effects on both human health and aquatic ecosystems. Traditional water treatment technologies, such as coagulation, sedimentation, and filtration, are not designed to effectively remove these recalcitrant compounds, leading to their persistence in treated water and potential re-entry into the environment.

[0003] Moreover, the transformation products resulting from incomplete degradation of these micropollutants during treatment processes can also exhibit increased toxicity and environmental persistence. Consequently, advanced treatment techniques have gained attention for their effectiveness in removing these contaminants. However, these advanced methods often entail higher operational costs and may generate secondary environmental impacts.Technical Problem

[0004] The established methods for removing micropollutants from drinking water sources in treatment plants, namely filtration, coagulation, sedimentation, ozonation, chlorination, adsorption, or softening, are not able to completely degrade these micropollutants. At most, they may chemically transform the parent compounds into other subproducts that can have higher acute and chronic toxicity potential, for example during an ozonation step, or remove them to a different phase or waste stream that requires further processing, for example during a (ultra)filtration or an adsorption step.

[0005] The state-of-the-art processes such as advanced biological, chemical, or physical processes obtain promising results in the degradation of organic or inorganic pollutants, but these processes are not able to fully tackle the simultaneous removal of both types of micropollutants in an efficient manner, or in a manner safe for water consumption.

[0006] Physical methods such as ultrafiltration or reverse osmosis are very energy intensive and waste streams require further treatment. Advanced oxidation processes, in cases where total mineralization of organic pollutants is achieved, generate several harmful inorganic compounds. Biological treatments are very sensitive to water quality while the potential for downstream contamination is a very real concern.

[0007] To address the growing concerns surrounding micropollutants in water sources, there is a need to develop cost-effective, sustainable, and energy-efficient water treatment technologies.Solution to Problem

[0008] The present invention differs from the technical background by combining catalytic oxidation and reduction reactors in a single system to simultaneously remove emerging organic and inorganic (micro)pollutants employing at least a catalytic bed comprising a catalytic oxidation bed and a catalytic bed comprising a catalytic reduction bed.

[0009] The present invention also solves the problems of the prior art by developing a new catalyst for oxidation-reduction system configured for water treatment by removal of organic and inorganic pollutants, to contribute to the degradation of organic micropollutants and inorganic pollutants.

[0010] Moreover, the invention contributes to the development of a catalyst for heterogeneous catalytic ozonation and for heterogeneous catalytic reduction comprising a macrostructured supporter, which shows monolith features. The catalyst of the present invention is an improvement on the typically used compacted powders catalysts, which are usually comprised in fixed-bed packed reactors because handling of compacted powders is inherently more difficult. Furthermore, compacted powders lead to several hydrodynamic issues such as the formation of preferential paths within the catalytic bed or very large pressure losses. These issues are easily avoided by the deployment of the catalysts as a single ready-made unit.Advantageous Effects of Invention

[0011] The proposed invention presents several technical advantages. The combined processes (catalytic ozonation and reduction) are able, on themselves, to remove emerging organic and inorganic (micro)pollutants more efficiently, respectively, than the conventional methods employed in water treatment plants or wastewater treatment plants. Moreover, the invention presents advantages compared with other state-of-the-art methods primarily for promoting not only the degradation and ultimately mineralization of organic pollutants, but also the transformation of resulting inorganic subproducts into non-harmful substances.

[0012] Most organic pollutants contain nitrogen, chlorine, or bromine in their composition, which are known to result in inorganic pollutants such as nitrate, perchlorate, or bromate. Moreover, bromate can also be formed during the ozonation of bromide-containing waters. Finally, the use of a catalyst during the ozonation of the organic pollutants can also define reaction pathways towards the decreased formation of the harmful inorganic pollutants.

[0013] The oxidation-reduction system of the present invention is designed and deployed as a single unit which also severely decreases the required footprints for installation in water treatment plants or wastewater treatment plants.

[0014] To promote an understanding of the principles of the embodiments of the present invention, reference will be made to the embodiments illustrated in the figures and to the language used to describe the same. Anyway, it must be understood that there is no intention of limiting the scope of the present invention to the contents of the figures. Any alterations or later changes of the inventive features illustrated herein, and any additional application of the principles and embodiments of the invention shown, which would occur normally for one skilled in the art when reading this description, are considered as being within the scope of the claimed invention.Fig.1

[0015] illustrates a first embodiment of an oxidation-reduction system according to the present invention;Fig.2

[0016] illustrates a second embodiment of an oxidation-reduction system according to the present invention;Fig.3

[0017] illustrates a macrostructured catalyst for heterogeneous catalytic ozonation and for heterogeneous catalytic reduction comprising a ceramic cordierite honeycomb supporter coated with a carbon-based active component;Fig.4

[0018] illustrates a diagram with Taylor flow hydrodynamic regime inside a honeycomb channel of the supporter;Fig.5

[0019] illustrates an integrated treatment process for bromate based pollutants degradation;Fig.6

[0020] presents results of bromate based pollutants concentration during single ozonation;Fig.7

[0021] presents results of bromate based pollutants concentration during a catalytic ozonation in the presence of monolith prepared by the washcoating process;Fig.8

[0022] presents results of BrO3-concentration during a catalytic ozonation step and during an integrated oxidation-reduction treatment.

[0023] The present invention refers, in a first aspect, to an oxidation-reduction system configured for water or wastewater treatment by removal of organic and inorganic pollutants comprising:

[0024] a catalytic oxidation multiphase reactor (1) including a catalytic oxidation bed (2); and

[0025] a water or wastewater feed line (3); and

[0026] an ozone feed line (4); and

[0027] an oxidation products line (5); and

[0028] a catalytic reduction multiphase reactor (6) including a catalytic reduction bed (7); and

[0029] a hydrogen feed line (8); and

[0030] a reduction products line (9); and

[0031] wherein

[0032] at least one of the group consisting of said catalytic oxidation bed (2) or said catalytic reduction bed (7) comprises a macrostructured catalyst comprising:

[0033] at least one active component selected from a group consisting of a metal, a metal oxide, or a carbon-based material; and a macrostructured supporter; and wherein

[0034] said catalytic oxidation multiphase reactor (1) is arranged in series with said catalytic reduction multiphase reactor (6); and wherein

[0035] said water or wastewater feed line (3) is connected to a water inlet arranged at said catalytic oxidation multiphase reactor (1); and wherein

[0036] said ozone feed line (4) is connected to an ozone inlet arranged at a bottom section of said catalytic oxidation multiphase reactor (1); and wherein

[0037] said oxidation products line (5) is connected to an oxidation products outlet arranged at said catalytic oxidation multiphase reactor (1), and to an oxidation products inlet arranged at said catalytic reduction multiphase reactor (6); and wherein

[0038] said hydrogen feed line (8) is connected to a hydrogen inlet arranged at a bottom section of said catalytic reduction multiphase reactor (6); and wherein

[0039] said reduction products line (9) is connected to a reduction products outlet arranged at said catalytic reduction multiphase reactor (6); and wherein

[0040] at least one of the group consisting of said catalytic oxidation multiphase reactor (1) or said catalytic reduction multiphase reactor (6) is a bubble column reactor.

[0041]

[0042] The present invention refers, in a second aspect, to a method for water or wastewater treatment by removal of organic and inorganic pollutants using the oxidation-reduction system, as defined in the first aspect, and comprising the following steps:

[0043] a) contacting a water feed or a wastewater feed with an ozone feed in a catalytic oxidation bed (2) of a catalytic oxidation multiphase reactor (1), wherein a catalytic oxidation of oxidizable pollutants is conducted, obtaining an oxidation products stream; and

[0044] b) contacting the oxidation products stream with a hydrogen feed in a catalytic reduction bed (7) of a catalytic reduction multiphase reactor (6), wherein a catalytic reduction of reducible pollutants is conducted, obtaining a reduction products stream.

[0045]

[0046] A macrostructured catalyst is a type of catalyst that possesses a well-defined macroscopic structure, often in the form of a particular shape, pattern, or arrangement of catalytically active materials. Unlike traditional catalysts that are typically in powder or granular form, macrostructured catalysts are engineered to have larger and more defined structures. These structures can be tailored to enhance the performance and efficiency of catalytic reactions. A macrostructured catalyst according to the invention can be a monolith, a foam, a film or a coating, an ordered structure, or a hollow structure.

[0047] Monoliths are often structured catalysts with a honeycomb-like structure, wherein the channels within the monolith provide a large surface area for catalytic reactions. Metal or ceramic foams can be used as catalyst supports, and the open-cell structure of foams offers a large surface area and good fluid flow characteristics. Macrostructured catalysts can also be in the form of films or coatings, allowing precise control over the active surface area.

[0048] A macrostructured catalyst monolith is a type of structured catalyst characterized by its honeycomb-like structure, which resembles a monolith. This structure consists of a solid piece of material with a regular arrangement of open channels or passages running through it. These channels provide a significant surface area for catalytic reactions to occur, namely in the range of 200 to 1200 m2g-1.

[0049] The monolithic structure of these catalysts is often made from materials like ceramics, metals, or polymers. The channels within the monolith can vary in size, shape, and arrangement, depending on the specific application and catalytic reaction being targeted. The design of the monolith structure can be customized to optimize reactant flow, heat transfer, and mass transport, all of which contribute to efficient catalytic performance. The open channels allow reactants to flow through the monolith, facilitating efficient mass transport to the catalytic sites. This helps overcome diffusion limitations that can occur in traditional catalyst forms.

[0050] Preferably, in the oxidation-reduction system illustrated in Figures 1 or 2, said catalytic oxidation multiphase reactor (1) and said catalytic reduction multiphase reactor (6) are bubble column reactors. Preferably, the catalytic oxidation bed (2) and the catalytic reduction bed (7) comprise a macrostructured catalyst.

[0051] In a first preferred embodiment, as illustrated in, the water or wastewater feed line (3) is connected to a water inlet arranged at a bottom section of said catalytic oxidation multiphase reactor (1); and the oxidation products line (5) is connected to an oxidation products outlet arranged at a top section of said catalytic oxidation multiphase reactor (1), and to an oxidation products inlet arranged at a bottom section of said catalytic reduction multiphase reactor (6); and the reduction products line (9) is connected to a reduction products outlet arranged at a top section of said catalytic reduction multiphase reactor (6).

[0052] In the first preferred embodiment, step a) of the method for water or wastewater treatment by removal of organic and inorganic pollutants, according to the second aspect, comprises the following stages:

[0053] i. the water feed or the wastewater feed and the ozone are fed at a bottom section of the catalytic oxidation multiphase reactor (1), wherein the catalytic oxidation multiphase reactor (1) is a first bubble column reactor, and the water feed or the wastewater feed and the ozone flow from the bottom of the first bubble column reactor to its top, passing through the catalytic oxidation bed (2); and

[0054] ii. the oxidation products stream flows from a top section of the catalytic oxidation multiphase reactor (1);

[0055] and step b) comprises the following stages:

[0056] iii. the oxidation products stream and the hydrogen are fed at a bottom section of the catalytic reduction multiphase reactor (6), wherein the catalytic reduction multiphase reactor (6) is a second bubble column reactor, and the oxidation products stream and the hydrogen flow from the bottom of the second bubble column reactor to its top, passing through the catalytic reduction bed (7); and

[0057] iv. the reduction products stream flows from a top section of the catalytic reduction multiphase reactor (6).

[0058]

[0059] In the first preferred embodiments, the integrated oxidation-reduction system comprises two bubble columns installed in series in a single unit. The water feed with the organic and inorganic pollutants is pumped into the catalytic oxidation multiphase reactor (1) where it is contacted with the ozone feed, which acts as an oxidizing agent, wherein the ozone is bubbled from the bottom of the column through a porous ceramic plate. The water feed and the ozone flow from the bottom of the first bubble column reactor to its top, passing through the catalytic oxidation bed (2). The oxidation products stream comprising inorganic pollutants is then pumped into a catalytic reduction multiphase reactor (6) having a similar operation, wherein hydrogen is used as a reducing agent. The oxidation products stream feed and the hydrogen flow from the bottom of the second bubble column reactor to its top, passing through the catalytic reduction bed (7). The reduction products stream, which is the final effluent is then directed to further treatment or directly to the water distribution network, depending on the whole plant design and other water quality requirements.

[0060] The liquid (water) and gas (ozone) phases flow simultaneously through the catalytic oxidation bed (2) comprising the solid catalyst supported on a macrostructured supporter, for example a ceramic macrostructure, where a favourable hydrodynamic regime (Taylor flow or bubble train) promotes the mixing and contact of the phases by the generation of vortices on the liquid slugs flowing in between the gas bubbles.illustrates a diagram with Taylor flow hydrodynamic regime showing vortices formation in liquid slugs. The ozone contacts with the catalyst to form highly reactive oxygenated radicals, namely hydroxyl radicals, that non-selectively degrade the organic pollutants either on the catalyst surface or in the liquid bulk.

[0061] In the first preferred embodiment, the oxidation-reduction system further comprises a first recirculation line (14), which is connected to a recirculation outlet arranged at an upper section of said catalytic oxidation multiphase reactor (1) and to a recirculation inlet arranged at a lower section of said catalytic oxidation multiphase reactor (1), and wherein said catalytic oxidation bed (2) is arranged between said recirculation outlet and said recirculation inlet. Therefore, the water phase can be recirculated downstream to upstream of the catalytic oxidation bed (2), at a flow about ten times that of the water for treatment, to increase contact time and to approach the residence time distribution of the reactor to a series of continuous stirred tank reactors (CSTR).

[0062] Therefore, in the first preferred embodiment, the method for water or wastewater treatment by removal of organic and inorganic pollutants, according to the second aspect, comprises recirculation of the products streams of each one of multiphase reactors, wherein a portion of the oxidation products stream is recirculated along a first recirculation line (14) from an upper section of said catalytic oxidation multiphase reactor (1) to a lower section of said catalytic oxidation multiphase reactor (1), and wherein said catalytic oxidation bed (2) is arranged between said upper section and said lower section of the catalytic oxidation multiphase reactor (1); and wherein a portion of the reduction products stream is recirculated along a second recirculation line (15) from an upper section of said catalytic reduction multiphase reactor (6) to a lower section of said catalytic reduction multiphase reactor (6), and wherein said catalytic reduction bed (7) is arranged between said upper section and said lower section of the catalytic reduction multiphase reactor (1).

[0063] In the preferred embodiments of the invention, the oxidation-reduction system is operated in a counter-current mode but said system also can be operated in a co-current mode.

[0064] In a second preferred embodiment, as illustrated in, the water or wastewater feed line (3) is connected to a water inlet arranged at a top section of said catalytic oxidation multiphase reactor (1); and the oxidation products line (5) is connected to an oxidation products outlet arranged at a bottom section of said catalytic oxidation multiphase reactor (1), and to an oxidation products inlet arranged at a top section of said catalytic reduction multiphase reactor (6); and the reduction products line (9) is connected to a reduction products outlet arranged at a bottom section of said catalytic reduction multiphase reactor (6).

[0065] In the second preferred embodiment, step a) of the method for water or wastewater treatment by removal of organic and inorganic pollutants, according to the second aspect, comprises the following stages:

[0066] i. the water feed or the wastewater feed is fed at a top section of the catalytic oxidation multiphase reactor (1) and the ozone is fed at a bottom section of the catalytic oxidation multiphase reactor (1), and the water feed or the wastewater feed and the ozone flow counter current, passing through the catalytic oxidation bed (2); and

[0067] ii. the oxidation products stream flows from a bottom section of the catalytic oxidation multiphase reactor (1);

[0068] and wherein step b) comprises the following stages:

[0069] iii. the oxidation products stream is fed at a top section of the catalytic reduction multiphase reactor (6) and the hydrogen is fed at a bottom section of the catalytic reduction multiphase reactor (6), and the oxidation products stream and the hydrogen flow counter current, passing through the catalytic reduction bed (7); and

[0070] the reduction products stream flows from a bottom section of the catalytic reduction multiphase reactor (6).

[0071]

[0072] In the second preferred embodiment, as illustrated in, said oxidation-reduction system further comprises a first recirculation line (14), which is connected to a recirculation outlet arranged at a lower section of said catalytic oxidation multiphase reactor (1) and to a recirculation inlet arranged at an upper section of said catalytic oxidation multiphase reactor (1), and wherein said catalytic oxidation bed (2) is arranged between said recirculation outlet and said recirculation inlet. Furthermore, said oxidation-reduction system further comprises a second recirculation line (15), which is connected to a recirculation outlet arranged at a lower section of said catalytic reduction multiphase reactor (6) and to a recirculation inlet arranged at an upper section of said catalytic reduction multiphase reactor (6), and wherein said catalytic reduction bed (7) is arranged between said recirculation outlet and said recirculation inlet.

[0073] Therefore, in the second preferred embodiment, the method for water or wastewater treatment by removal of organic and inorganic pollutants, according to the second aspect, comprises recirculation of the products streams of each one of multiphase reactors, wherein a portion of the oxidation products stream is recirculated along a first recirculation line (14) from a lower section of said catalytic oxidation multiphase reactor (1) to an upper section of said catalytic oxidation multiphase reactor (1), and wherein said catalytic oxidation bed (2) is arranged between said upper section and said lower section of the catalytic oxidation multiphase reactor (1); and wherein a portion of the reduction products stream is recirculated along a second recirculation line (15) from a lower section of said catalytic reduction multiphase reactor (6) to an upper section of said catalytic reduction multiphase reactor (6), and wherein said catalytic reduction bed (7) is arranged between said upper section and said lower section of the catalytic reduction multiphase reactor (1).

[0074] Preferably, as illustrated in Figures 1 or 2, the oxidation-reduction system further comprises an ozone production unit (10) for producing ozone in situ, wherein said ozone feed line (4) is connected to an ozone outlet of said ozone production unit (10), and an oxygen feed line (12) is connected to an oxygen inlet of said ozone production unit (10). As it will be understood by a person skilled in the art, the ozone production unit (10) can be a Corona Discharge generator, an Ultraviolet Radiation generator, a Cold Plasma generator, or an Electrolytic Ozone Generator.

[0075] Preferably, as illustrated in Figures 1 or 2, the oxidation-reduction system further comprises an oxygen production unit (11), wherein said oxygen feed line (12) is connected to an oxygen outlet of said oxygen production unit (11). As it will be understood by a person skilled in the art, the oxygen production unit (11) can be a Fractional Distillation of Air unit, a Pressure Swing Adsorption device, or a device configured for the electrolysis of water.

[0076] Preferably, as illustrated in Figures 1 or 2, the oxidation-reduction system further comprises a hydrogen production unit (13), wherein said hydrogen feed line (8) is connected to a hydrogen outlet of said hydrogen production unit (13). As it will be understood by a person skilled in the art, the hydrogen production unit (13) can be a Steam Methane Reforming unit, a device configured for the electrolysis of water, a biomass gasifier, or a coal gasifier.

[0077] In the preferred embodiments, the oxidation-reduction system further comprises a second recirculation line (15), which is connected to a recirculation outlet arranged at an upper section of said catalytic reduction multiphase reactor (6) and to a recirculation inlet arranged at a lower section of said catalytic reduction multiphase reactor (6), and wherein said catalytic reduction bed (7) is arranged between said recirculation outlet and said recirculation inlet.

[0078] In the preferred embodiments, the catalytic oxidation-reduction system can further comprise exhaustion outlets for unconverted gases, namely an ozone outlet line (16), which is connected to a top outlet arranged at a top section of the catalytic oxidation multiphase reactor (1), and a hydrogen outlet line (17), which is connected to a top outlet arranged at a top section of the catalytic reduction multiphase reactor (6). Each one of the ozone outlet line (16) and the hydrogen outlet line (17) can comprise a derivation line for collecting samples of the exhaustion gases.

[0079] The bottom section of the catalytic oxidation multiphase reactor (1) is provided with a first gas distribution arrangement, which can comprise a grid provided with nozzles, through which ozone is introduced into the catalytic oxidation multiphase reactor (1) for process purposes. Similarly, the bottom section of the catalytic reduction multiphase reactor (6) is provided with a second gas distribution arrangement, which can comprise a grid provided with nozzles, through which hydrogen is introduced into the catalytic reduction multiphase reactor (6) for process purposes.

[0080] As used in this description, the expression “bottom section” refers to a zone comprising the first one-third of the height of said catalytic oxidation multiphase reactor (1) or said catalytic reduction multiphase reactor (6), preferably the first one-quarter of the height.

[0081] As used in this description, the expression “top section” refers to a zone comprising the last one-third of the height of said catalytic oxidation multiphase reactor (1) or said catalytic reduction multiphase reactor (6), preferably the last one-quarter of the height.

[0082] As used in this description, the expression “lower section” refers to a zone comprising the first half of the height of said catalytic oxidation multiphase reactor (1) or said catalytic reduction multiphase reactor (6), preferably the first one-third of the height.

[0083] As used in this description, the expression “upper section” refers to a zone comprising the last half of the height of said catalytic oxidation multiphase reactor (1) or said catalytic reduction multiphase reactor (6), preferably the last one-third of the height.

[0084] The present invention refers, in a third aspect, to a catalyst for heterogeneous catalytic ozonation and / or for heterogeneous catalytic reduction comprising:

[0085] at least one active component selected from a group consisting of a metal, a metal oxide, or a carbon-based material; and a macrostructured supporter.

[0086] In the preferred embodiments, the catalytic oxidation bed (2) comprises a preferred macrostructured catalyst for heterogeneous catalytic ozonation, which comprises a metal active component selected from a group consisting of platinum, palladium, iron, manganese, titanium, cerium, copper, silver, cobalt, or mixtures thereof.

[0087] In other preferred embodiments, the catalytic oxidation bed (2) comprises a preferred macrostructured catalyst for heterogeneous catalytic ozonation, which comprises a metal oxide active component selected from a group consisting of aluminum oxide, aluminum oxyhydroxide, titanium dioxide, manganese oxide MnxOy, manganese dioxide, calcium manganese oxide, zinc oxide, zirconium dioxide, and titanium dioxide, iron oxide FexOy, iron oxyhydroxide, copper oxide, cerium oxide, magnesium oxide, stannic oxide, cobalt oxide, nickel(III) oxide, chromium(III) oxide, or mixtures thereof, and wherein x is an integer from 1 to 3, y is an integer from 1 to 4.

[0088] In other preferred embodiments, the catalytic oxidation bed (2) comprises a macrostructured catalyst for heterogeneous catalytic ozonation, which comprises a carbon-based material active component selected from a group consisting of activated carbon, carbon nanotubes, graphene oxide, carbon nitride, or composites thereof.

[0089] In other preferred embodiments, the catalytic reduction bed (7) comprises a macrostructured catalyst for heterogeneous catalytic reduction, which comprises a metal active component selected from a group consisting of platinum, palladium, ruthenium, rhodium, nickel, cobalt, copper, iron, molybdenum, silver, or mixtures thereof, wherein said catalyst is optionally supported in a supporter selected from a group consisting of activated carbon, alumina, silica, zeolites, or combinations thereof.

[0090] In the preferred embodiments, the macrostructured supporter is at least one of the group consisting of a metal fiber, a carbon felt, a honeycomb ceramic monolith, a silicon-carbide foam, a mulite, an alumina, or composites thereof. Preferably, the macrostructured supporter is a honeycomb ceramic monolith, namely cordierite.

[0091] Cordierite is a magnesium iron aluminium cyclosilicate having the general formula:

[0092] (Mg,Fe)2Al3(AlSi5O18).

[0093] The cordierite acts as a macrostructured ceramic supporter material comprising a honeycomb structure, which allows the flow-through its structure.

[0094] illustrates a macrostructured catalyst for heterogeneous catalytic ozonation and / or for heterogeneous catalytic reduction comprising a ceramic cordierite honeycomb supporter coated with a carbon-based component. When the macrostructured catalyst is designed for heterogeneous catalytic ozonation, said carbon-based component is the active component. In other embodiments of the invention, when the macrostructured catalyst is designed for heterogeneous catalytic reduction, said carbon-based component can be a support layer decorated with active metallic nanoparticles. The upper left part ofshows the carbon-based active component, and the upper right part ofpresents a micrograph of the carbon component, viewed in grey, and the covered cordierite, viewed in pink. Transmission electron microscopy (TEM) images of carbon nanotubes and carbon nanotubes decorated with metals are also shown in the lower part of.

[0095] In the preferred embodiments of the present invention, the catalyst according to the first aspect is for heterogeneous catalytic ozonation, and the metal active component is selected from a group consisting of platinum, palladium, iron, manganese, titanium, cerium, copper, silver, cobalt, or mixtures thereof.

[0096] In other embodiments, the catalyst according to the first aspect is for heterogeneous catalytic ozonation, and the metal oxide active component is selected from a group consisting of aluminum oxide, aluminum oxyhydroxide, titanium dioxide, manganese oxide MnxOy, manganese dioxide, calcium manganese oxide, zinc oxide, zirconium dioxide, and titanium dioxide, iron oxide FexOy, iron oxyhydroxide, copper oxide, cerium oxide, magnesium oxide, stannic oxide, cobalt oxide, nickel(III) oxide, chromium(III) oxide, or mixtures thereof, and wherein x is an integer from 1 to 3, y is an integer from 1 to 4.

[0097] In the preferred embodiments, the catalyst according to the first aspect is for heterogeneous catalytic ozonation, and the carbon-based material active component is selected from a group consisting of activated carbon, carbon nanotubes, graphene oxide, carbon nitride, or composites thereof.

[0098] The best-performing catalysts for ozonation comprise carbon-base materials tailored to specific targeted organic pollutants, wherein said catalysts have high specific surface areas (>200 m2g-1), mesoporous porosity (median pore diameter of 16 to 20 nm), and a basic surface pH.

[0099] In the preferred embodiments, the catalyst according to the first aspect is for heterogeneous catalytic reduction, and said metal active component is selected from a group consisting of platinum, palladium, ruthenium, rhodium, nickel, cobalt, copper, iron, molybdenum, silver, or mixtures thereof. In the most preferred embodiments, said heterogeneous catalytic reduction comprises the metal active supported in a first supporter selected from a group consisting of activated carbon, alumina, silica, zeolites, or combinations thereof, and the first supporter is supported in said macrostructured supporter.

[0100] Moreover, in the most preferred embodiments, the catalysts for the reduction step can also comprise tailored carbon-based materials, which are used as a supporter, or carbon-based materials can be used in combination, in an optimized ratio, with a transition metallic oxide, namely in a range of 20:80 to 80:20. In other embodiments, the metallic active phase comprises a combination of a noble metal (platinum group metals) and a transition metal, namely palladium and copper, at a total loading of 1 to 5% for each active metal(mass percentage in relation to the overall mass of the catalyst), and the ratio between the noble metal and the transition metal is in the range of 20:80 to 80:20.

[0101] In other preferred embodiments, the catalyst for heterogeneous catalytic ozonation can be doped with heteroatoms, such as nitrogen, or decorated with transition metallic particles selected for the target pollutants.

[0102] Preferably, the catalyst for heterogeneous catalytic ozonation or the catalyst for heterogeneous catalytic reduction comprises said active component in a mass percentage of 2 % to 25 % in relation to the overall mass of said catalyst. In these preferred embodiments, said macrostructured supporter is in a mass percentage of 75 % to 98 % in relation to the overall mass of said catalyst. Besides the active component and the macrostructured supporter, the catalyst can comprise at least one component selected from the group consisting of a binder, a stabilizer, or a modifier.

[0103] The present invention refers, in a fourth aspect, to a method for preparing the catalyst for heterogeneous catalytic ozonation and / or for heterogeneous catalytic reduction, as defined in the third aspect, wherein said method comprises the following steps:

[0104] a) performing particle size reduction of the active component, obtaining milled particles of the active component; and

[0105] b) mixing the milled particles of the active component with a liquid vehicle, obtaining a suspension or a slurry of the active component; and

[0106] c) adsorbing the active component of the suspension or a slurry of the active component in a macrostructured supporter, obtaining a macrostructured supporter coated by an active component; and

[0107] d) calcinating the macrostructured supporter coated by an active component, obtaining the catalyst for heterogeneous catalytic ozonation and / or for heterogeneous catalytic reduction.

[0108]

[0109] Preferably, at least one of a surfactant or a binder is mixed withthe milled particles of the active component and the liquid vehicle in step b). In the most preferred embodiments, a non-ionic surfactant can be used, namely Triton X-100, Triton X-114, Tween surfactants, such as Tween 20 (polysorbate 20) and Tween 80 (polysorbate 80), Sodium dodecyl sulfate (SDS), Sodium alginate / alginic acid, polyvinyl acetate, aerosol OS surfactant (sodium diisopropylnaphthalene sulfonate), dodecyl-benzene sodium sulfonate (NaDDBS), Polyethylene Glycol Alkyl Ethers, Octylphenol Ethoxylates, Pluronic surfactants (triblock copolymers composed of polyethylene oxide (PEO) and polypropylene oxide (PPO) blocks), Sorbitan Fatty Acid Esters, Alkylphenol Ethoxylates, or ethoxylated alkylphenols.

[0110] In the preferred embodiments, the adsorbing in step c) is executed by dip coating the macrostructured supporter in the suspension or in the slurry of the active component vehicle.

[0111] Even more preferably, a drying step of the macrostructured supporter coated by the active component is executed before said step d).

[0112] The present invention refers, in a fifth aspect, to a method for preparing the catalyst for heterogeneous catalytic ozonation and / or for heterogeneous catalytic reduction, as defined in the third aspect, wherein said method comprises the following steps:

[0113] a) preparing a liquid solution of a precursor of the active component; and

[0114] b) contacting the liquid solution of the previous step with a macrostructured supporter, and adsorbing the precursor of the active component in the macrostructured supporter, obtaining a macrostructured supporter coated by a precursor of the active component; and

[0115] c) executing a thermal treatment of the macrostructured supporter coated by the precursor of the active component, obtaining the catalyst for heterogeneous catalytic ozonation and / or for heterogeneous catalytic reduction.

[0116]

[0117] In the preferred embodiments, the thermal treatment of step d) comprises at least one of the group consisting of a calcination and a reduction thermal treatment. Even more preferably, a drying step of the macrostructured supporter coated by the precursor of the active component is executed before said step d).

[0118] In other preferred embodiments, the macrostructured catalyst monolith can be doped with nitrogen, wherein said doping can offer several advantages, particularly in heterogeneous catalytic processes. Nitrogen doping can introduce additional active sites on the catalyst surface, which can enhance the catalytic activity of the monolith. Nitrogen-containing groups can participate in reaction mechanisms, leading to increased rates of target reactions. Nitrogen functionalities can influence the reaction pathways and selectivity of catalytic processes. Doping with nitrogen can promote specific reaction pathways and suppress undesired side reactions, leading to higher selectivity for the desired products. Nitrogen-containing groups can improve the adsorption of reactant molecules onto the catalyst surface, facilitating their interaction with active sites. This can lead to more efficient utilization of reactants and improved catalytic performance. Nitrogen doping can enhance the stability and durability of the catalyst by strengthening the catalyst-support interactions, reducing metal particle sintering, and inhibiting catalyst deactivation mechanisms. Nitrogen-doped catalysts may show improved resistance to poisoning by contaminants or inhibitors present in the reaction feed. The nitrogen functionalities can mitigate the negative effects of certain species that might otherwise block active sites.

[0119] Common nitrogen-doping molecules include ammonia, amines, amides, nitriles, nitrogen oxides, such as nitric oxide (NO) or nitrogen dioxide (NO2), urea, melamine, polymers with nitrogen-containing functional groups, such as polyvinylpyrrolidone (PVP) or polyethyleneimine (PEI), or nitrogen gas.

[0120] In addition to nitrogen-doping molecules, various other doping molecules can be used to modify the properties and enhance the performance of a macrostructured catalyst monolith. These doping molecules can introduce different functionalities, surface characteristics, and catalytic behavior to the monolith. Phosphorus-containing molecules, such as phosphoric acid, phosphates, or phosphine derivatives, can be used to introduce phosphorus into the monolith. Phosphorus doping can affect the acid-base properties of the catalyst and enhance its activity in certain reactions. Sulfur-containing molecules, including thiols, sulfides, and sulfates, can be used to introduce sulfur functionalities to the monolith. Sulfur doping can modify the redox behavior and surface chemistry of the catalyst. Oxides of various metals, such as ceria (CeO2), zirconia (ZrO2), or titania (TiO2), can be used as doping materials to improve the catalyst's catalytic properties, redox behavior, and thermal stability. Certain transition metal compounds, such as oxides, sulfides, or salts of metals like iron, cobalt, or nickel, can be used as dopants to enhance catalytic activity and selectivity in specific reactions. Rare earth elements and their compounds, such as lanthanum (La), cerium (Ce), and yttrium (Y), can be used for doping to modify the surface properties and catalytic behavior of the monolith. Compounds like acids (e.g., sulfuric acid) or bases (e.g., sodium hydroxide) can be used to introduce acid-base sites on the monolith surface, which can influence catalytic activity and reaction mechanisms. Carbon-containing molecules, such as activated carbon or carbon nanotubes, can be used to modify the monolith's surface properties and enhance adsorption and reactivity. Ionic liquids can be used as doping agents to introduce unique properties to the catalyst surface, such as improved solubility, enhanced mass transfer, and altered interactions with reactants. Halogens like fluorine, chlorine, bromine, and iodine can be used as dopants to introduce specific surface functionalities and alter the electronic properties of the monolith.

[0121] In other preferred embodiments, the step c) referred to the adsorbing of the active component in the honeycomb ceramic cordierite can be achieved by dipping the macrostructured honeycomb ceramic cordierite in a suspension comprising the desired active component, and subsequent mixture with a composition to promote adherence of the active component to the cordierite, and subsequent calcination under nitrogen. Preferably, the composition to promote adherence comprises a suspension of a carbon-based material and a surfactant. More preferably, the composition to promote adherence comprises carbon-based material in the range of 1 wt.% to 4 wt.%, preferably about 2 wt.%. Preferably, the composition to promote adherence is prepared by mixing said suspension of a carbon-based material and a surfactant with water, wherein the mass ratio between said carbon-based material and the surfactant is in the range of 0.8:1 to 1.2:1, preferably 1:1. Triton X-100 is an example of a suitable surfactant. In these embodiments, the calcinating step is carried out under flowing nitrogen at a temperature of 450 to 650 ºC, preferably at about 550ºC, for 1 to 2 hours, to remove the surfactant.Examples

[0122] Sample preparation

[0123] Multi-walled carbon nanotubes (MWCNTs) were used as carbon-based material active component, Triton X-100 was used as a dispersant, and cordierite was used as a macrostructured supporter.

[0124] The multi-walled carbon nanotubes (MWCNTs) and selected dispersant were added to water as a solvent and kept under stirring for 1h. The solutions were sonicated for 1 h (Hielsher UP400S; 50% amplitude and 5 s–1frequency) to promote deagglomeration of the MWCNTs bundles aided by action of the dispersant. The resulting homogeneous slurries were then used for the dip-coating (Bungard RDC21K coater; 30 mm min–1dipping speed and 1 min of immersion) of the cordierite monoliths (previously calcined in air at 900 °C to remove impurities) after pH adjustment with HCl or NaOH. The amount of dispersant used were adjusted to maintain a 1:1 weight ratio with the MWCNTs in the slurries. The supporter was dipped five times in the homogeneous slurries, with a 1 h drying step at 100 °C in static air intercalated. After the final drying step, the samples were calcined in a 100 cm3min–1N2flow at 550 °C for 1 h to fully remove the dispersant left in the catalyst. Pre- and postcoating steps were applied to control the morphology and the chemical and textural surface properties of the MWCNTs.

[0125] Precoating Modification of the MWCNTs

[0126] Precoating modification of MWCNTs was carried out before they are added to the slurry described above. Precoating steps include oxidation with boiling 7 M HNO3carried out for 3 h, doping with nitrogen using melamine as a precursor milled together with MWCNTs in a ball mill (Retsch MM200; 4 h at 15 s–1frequency), and ball milling at varying times with no added precursors to the MWCNTs.

[0127] PostcoatingTreatment

[0128] Postcoating steps are based in the thermal treatment of the coated samples under flowing N2(1 h dwell, 100 cm3min–1) at varying temperatures to stabilize the coating and selectively remove surface groups. 550 °C is used to stabilize the coating, 600 °C is used for the samples containing melamine to complete the heteroatom doping procedure, and 900 °C is used to remove most oxygen-containing surface groups.

[0129] Incorporation of Ce / MWCNTs composites

[0130] Macrostructured catalysts were prepared using a dip-coating (Bungard RDC21 K dip-coater) technique. In brief, the powder composite of cerium oxide and multi-walled carbon nanotubes (MWCNTs) catalysts were dispersed in water using a non-ionic surfactant (Triton X-100™) and an ultrasonic probe (Hielscher UP400S) prior to dip-coating on a cordierite honeycomb monolith (60 × 22 mm). The coating process was repeated 5x on each end of the monolith. The dipping conditions (3 mm / min dipping speed, 1 min submersion in coating solution) were previously optimized to obtain high catalyst loading without compromising stability. After coating the resulting structured catalysts were dried overnight and calcined at 550 ◦C in nitrogen.

[0131] Incorporation of Pd and Pd-Cu on carbon coated cordierite macrostructures

[0132] The incorporation of Pd or Pd-Cu on the macrostructured support was achieved through two different techniques. The first one was applied to the previously carbon-coated supports (whose preparation was previously described) and consisted of an adsorption procedure for the incorporation of the metallic phase into the catalyst; an aqueous solution (5 % HCl) with the dissolved precursor (PdCl2in the case of monometallic catalysts or a mixture of PdCl2and Cu(NO3)2·3H2O DOR Pd-Cu catalysts) was prepared and the monoliths were placed in contact with the solution during 8 h in a shaking water bath to promote the flowing of the liquid through the monolith channels and promote the palladium adsorption. Then, the monolith was dried and a calcination / reduction thermal treatment, similar to the one applied to the carbon powder materials, was applied using different temperatures: 200 ºC, 350 ºC, and 550 ºC. These temperatures were chosen considering the calcination / reduction temperature selected for the preparation of monometallic powder materials (200 ºC), and higher calcination / reduction temperatures (350 and 550 ºC) were studied to perform the metal reduction, and the TX100 calcination step in one thermal treatment.

[0133] In the second approach, the washcoating procedure (WCP) was used for the synthesis of Pd / WCP and Pd-Cu / WCP macrostructured catalysts using the respective monometallic powder catalysts, 1% or 5% Pd on multi-walled carbon nanotubes (MWCNTs), and 5% Pd-2.5% Cu for the bimetallic catalysts, with and without the reductive thermal treatment applied on the powder material to prepare the coating solution involved in this procedure. The methodology used an organic binder, such as TX100, in order to achieve the appropriate dispersion of MWCNTs powders in the coating solutions. Because TX100 forms a hydrophilic layer around the MWCNTs, the access of reactants to the catalytic MWCNT surface (or surface Pd nanoparticles) is hindered or completely blocked, and thus an extra-step is required to remove the TX100 formed around the MWCNTs. This is readily achieved by thermal treating the coated macrostructures at 550 ºC. A washing methodology of the mono / bimetallic macrostructured catalyst was assessed using a solution of isopropanol:acetone to promote TX100 degradation while preserving metal nanoparticles structure and catalyst activation.

[0134] Experimental results obtained at the laboratory scale show the effect of the catalytic ozonation reaction on the degradation of a model organic pollutant and the effect of the catalytic reduction reaction to mineralize bromate formed during the ozonation process.

[0135] To validate the integrated water treatment by the oxidation-reduction system, firstly, a simulated water doped with bromide in a concentration around 20 mg / L was fed to the system, passed through the ozonation treatment sub-system (forming BrO3-), and then was forwarded to the hydrogenation sub-system, where it was intended to convert BrO3-back into bromide.

[0136] These experiments were conducted under different conditions, mainly varying the presence of catalysts in the two reactors: a blank experiment with no catalyst in any reactor, an experiment only with a bimetallic catalyst (2:1 palladium:copper) at 13 wt.% in relation to the overall mass of the catalyst present in the catalytic reduction multiphase reactor (6), and an experiment with specific catalysts in both reaction systems (carbon nanotubes based supported on cordierite catalyst in the catalytic oxidation multiphase reactor (1) and a bimetallic catalyst in the catalytic reduction multiphase reactor (6). Experiments were conducted at 10 cm3min-1water phase flow, 150 cm3min-1gas phase, and with a 100 g m-3ozone concentration in pure oxygen flow for the oxidation phase. Catalysts with approximately 10 g were used for each of the oxidation and reduction steps, wherein the active component of said catalyst for heterogeneous catalytic ozonation has about 0.6 g, and wherein the active component of said catalyst for heterogeneous catalytic reduction has about 2.9 g.

[0137] The obtained results showed that a single ozonation would lead to a higher formation of BrO3-than in the case of catalytic ozonation. However, in any of the cases, BrO3-could only be converted back into Br-when a bimetallic catalyst was present in the catalytic reduction multiphase reactor (6). In either case, a conversion value of 90 % was achieved for BrO3-conversion back into Br-.

[0138] Secondly, a simulated effluent consisting of about 1 mg / L of each model brominated compounds (bromophenol blue, tetrabromobisphenol A, and 2,4,6-tribromophenol) was submitted to the integrated treatment system (in the three different approaches of the catalysts present in the reaction previously mentioned), as illustrated in. The obtained results showed that single ozonation was capable of fully degrading the three organic pollutants and a concentration of around 410 µg / L of BrO3-would be formed. However, when forwarded to the catalytic hydrogenation reactor, BrO3-conversion into Br-was about 92 %. When using a catalyst during the ozonation reactor, the formed BrO3-formation was decreased by half (around 120 µg / L) and, that way, with the combination of both catalytic systems, it was possible to decay BrO3-concentration to values a little below 10 µg / L (advised legal limit) by the end of the integrated treatment.

[0139] presents the concentrations of each model brominated compounds (bromophenol blue, tetrabromobisphenol A, and 2,4,6-tribromophenol) in the simulated effluent, which if the feed to a single ozonation step, and post-treatment concentrations thereof.

[0140] presents the concentrations of each model brominated compounds (bromophenol blue, tetrabromobisphenol A, and 2,4,6-tribromophenol) in the simulated effluent, which if the feed to a single ozonation step executed in a bubble column reactor, wherein said reactor comprises a catalytic oxidation bed with a monolith prepared by the washcoating process, and post-treatment concentrations thereof.

[0141] presents the concentration of BrO3-after a single ozonation step, and after an integrated oxidation-reduction treatment using a system according to the invention.

[0142] The results of Figures 6 to 8 were obtained by running the experiments with a catalyst for heterogeneous catalytic ozonation comprising milled carbon nanotubes as the active component, which was prepared by washcoating, and with a catalyst for heterogeneous reduction comprising the composite MWCNT:TiO2(1:1), prepared by washcoating, and Pd-Cu (2:1) incorporation through a staged adsorption methodology with calcination / reduction thermal treatment between each phase.

[0143] As used in this description, the expressions “about” and “approximately” refer to a range in values of roughly 10% of the specified number.

[0144] As used in this description, the expression. “substantially” means that the real value is within an interval of about 10% of the desired value, variable or related limit, particularly within about 5% of the desired value, variable or related limit or particularly within about 1% of the desired value, variable or related limit.

[0145] Moreover, the term “or” is intended to mean an inclusive “or” rather than an exclusive “or.” That is unless specified otherwise, or clear from the context, the phrase “X employs A or B” is intended to mean any of the natural inclusive permutations. That is, the phrase “X employs A or B” is satisfied by any of the following instances: X employs A; X employs B; or X employs both A and B.

[0146] In addition, the articles “a” and “an” as used in this application and the appended claims should generally be construed to mean “one or more” unless specified otherwise or clear from the context to be directed to a singular form.

[0147] Further, as used herein, the term “exemplary” is intended to mean serving as an illustration or example of something and is not intended to indicate a preference.

[0148] The subject matter described above is provided as an illustration of the present invention and must not be interpreted to limit it. The terminology used with the purpose of describing specific embodiments, according to the present invention, must not be interpreted to limit the invention. As used in this description, the definite and indefinite articles, in their singular form, aim to include in the interpretation the plural forms, unless the context of the description explicitly indicates the contrary. It will be understood that the expressions “comprise” and “include”, when used in this description, specify the presence of the characteristics, the elements, the components, the steps, and the related operations, but do not exclude the possibility of other characteristics, elements, components, steps, and operations from being also contemplated.

[0149] All modifications, providing that they do not modify the essential features of the following claims, must be considered within the scope of protection of the present invention.

[0150] 1. A catalytic oxidation multiphase reactor;

[0151] 2. A catalytic oxidation bed;

[0152] 3. A water or wastewater feed line;

[0153] 4. An ozone feed line;

[0154] 5. An oxidation products line;

[0155] 6. A catalytic reduction multiphase reactor;

[0156] 7. A catalytic reduction bed;

[0157] 8. A hydrogen feed line;

[0158] 9. A reduction products line;

[0159] 10. An ozone production unit;

[0160] 11. An oxygen production unit;

[0161] 12. An oxygen feed line;

[0162] 13. A hydrogen production unit;

[0163] 14. A first recirculation line;

[0164] 15. A second recirculation line;

[0165] 16. An ozone outlet line;

[0166] 17. A hydrogen outlet line;

Claims

An oxidation-reduction system configured for water or wastewater treatment by removal of organic and inorganic pollutants comprising:a catalytic oxidation multiphase reactor (1) including a catalytic oxidation bed (2); anda water or wastewater feed line (3); andan ozone feed line (4); andan oxidation products line (5); anda catalytic reduction multiphase reactor (6) including a catalytic reduction bed (7); anda hydrogen feed line (8); anda reduction products line (9); andcharacterized in thatat least one of the group consisting of said catalytic oxidation bed (2) or said catalytic reduction bed (7) comprises a macrostructured catalyst comprising:at least one active component selected from a group consisting of a metal, a metal oxide, or a carbon-based material; and a macrostructured supporter; and whereinsaid catalytic oxidation multiphase reactor (1) is arranged in series with said catalytic reduction multiphase reactor (6); and whereinsaid water or wastewater feed line (3) is connected to a water inlet arranged at said catalytic oxidation multiphase reactor (1); and whereinsaid ozone feed line (4) is connected to an ozone inlet arranged at a bottom section of said catalytic oxidation multiphase reactor (1); and whereinsaid oxidation products line (5) is connected to an oxidation products outlet arranged at said catalytic oxidation multiphase reactor (1), and to an oxidation products inlet arranged at said catalytic reduction multiphase reactor (6); and whereinsaid hydrogen feed line (8) is connected to a hydrogen inlet arranged at a bottom section of said catalytic reduction multiphase reactor (6); and whereinsaid reduction products line (9) is connected to a reduction products outlet arranged at said catalytic reduction multiphase reactor (6); and whereinat least one of the group consisting of said catalytic oxidation multiphase reactor (1) or said catalytic reduction multiphase reactor (6) is a bubble column reactor.The oxidation-reduction system, according to the previous claim,whereinsaid oxidation-reduction system further comprises an ozone production unit (10), and wherein said ozone feed line (4) is connected to an ozone outlet of said ozone production unit (10), and wherein an oxygen feed line (12) is connected to an oxygen inlet of said ozone production unit (10).The oxidation-reduction system, according to the previous claim, wherein said oxidation-reduction system further comprises an oxygen production unit (11), and wherein said oxygen feed line (12) is connected to an oxygen outlet of said oxygen production unit (11).The oxidation-reduction system, according to any one of the previous claims, wherein said oxidation-reduction system further comprises a hydrogen production unit (13), and wherein said hydrogen feed line (8) is connected to a hydrogen outlet of said hydrogen production unit (13).The oxidation-reduction system, according to any one of the previous claims, wherein said water or wastewater feed line (3) is connected to a water inlet arranged at a bottom section of said catalytic oxidation multiphase reactor (1); and wherein said oxidation products line (5) is connected to an oxidation products outlet arranged at a top section of said catalytic oxidation multiphase reactor (1), and to an oxidation products inlet arranged at a bottom section of said catalytic reduction multiphase reactor (6); and wherein said reduction products line (9) is connected to a reduction products outlet arranged at a top section of said catalytic reduction multiphase reactor (6).The oxidation-reduction system, according to the previous claim, wherein said oxidation-reduction system further comprises a first recirculation line (14), which is connected to a recirculation outlet arranged at an upper section of said catalytic oxidation multiphase reactor (1) and to a recirculation inlet arranged at a lower section of said catalytic oxidation multiphase reactor (1), and wherein said catalytic oxidation bed (2) is arranged between said recirculation outlet and said recirculation inlet.The oxidation-reduction system, according to any one of the claims 5 or 6, wherein said oxidation-reduction system further comprises a second recirculation line (15), which is connected to a recirculation outlet arranged at an upper section of said catalytic reduction multiphase reactor (6) and to a recirculation inlet arranged at a lower section of said catalytic reduction multiphase reactor (6), and wherein said catalytic reduction bed (7) is arranged between said recirculation outlet and said recirculation inlet.The oxidation-reduction system, according to any one of claims 1 to 4, wherein said water or wastewater feed line (3) is connected to a water inlet arranged at a top section of said catalytic oxidation multiphase reactor (1); and wherein said oxidation products line (5) is connected to an oxidation products outlet arranged at a bottom section of said catalytic oxidation multiphase reactor (1), and to an oxidation products inlet arranged at a top section of said catalytic reduction multiphase reactor (6); and wherein said reduction products line (9) is connected to a reduction products outlet arranged at a bottom section of said catalytic reduction multiphase reactor (6).The oxidation-reduction system, according to the previous claim, wherein said oxidation-reduction system further comprises a first recirculation line (14), which is connected to a recirculation outlet arranged at a lower section of said catalytic oxidation multiphase reactor (1) and to a recirculation inlet arranged at an upper section of said catalytic oxidation multiphase reactor (1), and wherein said catalytic oxidation bed (2) is arranged between said recirculation outlet and said recirculation inlet.The oxidation-reduction system, according to any one of the claims 8 or 9, wherein said oxidation-reduction system further comprises a second recirculation line (15), which is connected to a recirculation outlet arranged at a lower section of said catalytic reduction multiphase reactor (6) and to a recirculation inlet arranged at an upper section of said catalytic reduction multiphase reactor (6), and wherein said catalytic reduction bed (7) is arranged between said recirculation outlet and said recirculation inlet.The oxidation-reduction system, according to any one of the previous claims, wherein said catalytic oxidation multiphase reactor (1) and said catalytic reduction multiphase reactor (6) are bubble column reactors.The oxidation-reduction system, according to any one of the previous claims, wherein said catalytic oxidation bed (2) comprises a macrostructured catalyst for heterogeneous catalytic ozonation, and said metal active component is selected from a group consisting of platinum, palladium, iron, manganese, titanium, cerium, copper, silver, cobalt, or mixtures thereof.The oxidation-reduction system, according to any one of the previous claims, wherein said catalytic oxidation bed (2) comprises a macrostructured catalyst for heterogeneous catalytic ozonation, and said metal oxide active component is selected from a group consisting of aluminum oxide, aluminum oxyhydroxide, titanium dioxide, manganese oxide MnxOy, manganese dioxide, calcium manganese oxide, zinc oxide, zirconium dioxide, and titanium dioxide, iron oxide FexOy, iron oxyhydroxide, copper oxide, cerium oxide, magnesium oxide, stannic oxide, cobalt oxide, nickel(III) oxide, chromium(III) oxide, or mixtures thereof, and wherein x is an integer from 1 to 3, y is an integer from 1 to 4.The oxidation-reduction system, according to any one of the previous claims, wherein said catalytic oxidation bed (2) comprises a macrostructured catalyst for heterogeneous catalytic ozonation, and said carbon-based material active component is selected from a group consisting of activated carbon, carbon nanotubes, graphene oxide, carbon nitride, or composites thereof.The oxidation-reduction system, according to any one of the previous claims, wherein said catalytic reduction bed (7) comprises a macrostructured catalyst for heterogeneous catalytic reduction, and said metal active component is selected from a group consisting of platinum, palladium, ruthenium, rhodium, nickel, cobalt, copper, iron, molybdenum, silver, or mixtures thereof.The oxidation-reduction system, according to any one of the previous claims, wherein said macrostructured supporter is at least one of the group consisting of a metal fiber, a carbon felt, a honeycomb ceramic monolith, a silicon-carbide foam, a mulite, an alumina, or composites thereof.A method for water or wastewater treatment by removal of organic and inorganic pollutantscharacterized byusing the oxidation-reduction system, as defined in any one of the previous claims, and comprising the following steps:contacting a water feed or a wastewater feed with an ozone feed in a catalytic oxidation bed (2) of a catalytic oxidation multiphase reactor (1), wherein a catalytic oxidation of oxidizable pollutants is conducted, obtaining an oxidation products stream; andcontacting the oxidation products stream with a hydrogen feed in a catalytic reduction bed (7) of a catalytic reduction multiphase reactor (6), wherein a catalytic reduction of reducible pollutants is conducted, obtaining a reduction products stream.The method for water or wastewater treatment by removal of organic and inorganic pollutants, according to the previous claim, wherein step a) comprises the following stages:i. the water feed or the wastewater feed and the ozone are fed at a bottom section of the catalytic oxidation multiphase reactor (1), wherein the catalytic oxidation multiphase reactor (1) is a first bubble column reactor, and the water feed or the wastewater feed and the ozone flow from the bottom of the first bubble column reactor to its top, passing through the catalytic oxidation bed (2); andii. the oxidation products stream flows from a top section of the catalytic oxidation multiphase reactor (1);and wherein step b) comprises the following stages:iii. the oxidation products stream and the hydrogen are fed at a bottom section of the catalytic reduction multiphase reactor (6), wherein the catalytic reduction multiphase reactor (6) is a second bubble column reactor, and the oxidation products stream and the hydrogen flow from the bottom of the second bubble column reactor to its top, passing through the catalytic reduction bed (7); andiv. the reduction products stream flows from a top section of the catalytic reduction multiphase reactor (6).The method for water or wastewater treatment by removal of organic and inorganic pollutants, according to the previous claim, wherein a portion of the oxidation products stream is recirculated along a first recirculation line (14) from an upper section of said catalytic oxidation multiphase reactor (1) to a lower section of said catalytic oxidation multiphase reactor (1), and wherein said catalytic oxidation bed (2) is arranged between said upper section and said lower section of the catalytic oxidation multiphase reactor (1); and wherein a portion of the reduction products stream is recirculated along a second recirculation line (15) from an upper section of said catalytic reduction multiphase reactor (6) to a lower section of said catalytic reduction multiphase reactor (6), and wherein said catalytic reduction bed (7) is arranged between said upper section and said lower section of the catalytic reduction multiphase reactor (1).The method for water or wastewater treatment by removal of organic and inorganic pollutants, according to claim 17, wherein step a) comprises the following stages:i. the water feed or the wastewater feed is fed at a top section of the catalytic oxidation multiphase reactor (1) and the ozone is fed at a bottom section of the catalytic oxidation multiphase reactor (1), and the water feed or the wastewater feed and the ozone flow counter current, passing through the catalytic oxidation bed (2); andii. the oxidation products stream flows from a bottom section of the catalytic oxidation multiphase reactor (1);and wherein step b) comprises the following stages:iii. the oxidation products stream is fed at a top section of the catalytic reduction multiphase reactor (6) and the hydrogen is fed at a bottom section of the catalytic reduction multiphase reactor (6), and the oxidation products stream and the hydrogen flow counter current, passing through the catalytic reduction bed (7); andiv. the reduction products stream flows from a bottom section of the catalytic reduction multiphase reactor (6).The method for water or wastewater treatment by removal of organic and inorganic pollutants, according to the previous claim, wherein a portion of the oxidation products stream is recirculated along a first recirculation line (14) from a lower section of said catalytic oxidation multiphase reactor (1) to an upper section of said catalytic oxidation multiphase reactor (1), and wherein said catalytic oxidation bed (2) is arranged between said upper section and said lower section of the catalytic oxidation multiphase reactor (1); and wherein a portion of the reduction products stream is recirculated along a second recirculation line (15) from a lower section of said catalytic reduction multiphase reactor (6) to an upper section of said catalytic reduction multiphase reactor (6), and wherein said catalytic reduction bed (7) is arranged between said upper section and said lower section of the catalytic reduction multiphase reactor (1).A catalyst for heterogeneous catalytic ozonation and / or for heterogeneous catalytic reduction comprising:at least one active component selected from a group consisting of a metal, a metal oxide, or a carbon-based material; and a macrostructured supporter.The catalyst, according to the previous claim,whereinthe catalyst is for heterogeneous catalytic ozonation, andsaid metal active component is selected from a group consisting of platinum, palladium, iron, manganese, titanium, cerium, copper, silver, cobalt, or mixtures thereof.The catalyst, according to any one of claims 22 to 23,whereinthe catalyst is for heterogeneous catalytic ozonation, and said metal oxide active component is selected from a group consisting of aluminum oxide, aluminum oxyhydroxide, titanium dioxide, manganese oxide MnxOy, manganese dioxide, calcium manganese oxide, zinc oxide, zirconium dioxide, and titanium dioxide, iron oxide FexOy, iron oxyhydroxide, copper oxide, cerium oxide, magnesium oxide, stannic oxide, cobalt oxide, nickel(III) oxide, chromium(III) oxide, or mixtures thereof, and wherein x is an integer from 1 to 3, y is an integer from 1 to 4.The catalyst, according to any one of claims 22 to 24,whereinthe catalyst is for heterogeneous catalytic ozonation, and said carbon-based material active component is selected from a group consisting of activated carbon, carbon nanotubes, graphene oxide, carbon nitride, or composites thereof.The catalyst, according to claim 22,whereinthe catalyst is for heterogeneous catalytic reduction, and said metal active component is selected from a group consisting of platinum, palladium, ruthenium, rhodium, nickel, cobalt, copper, iron, molybdenum, silver, or mixtures thereof.The catalyst, according to any one of claims 22 to 26,whereinsaid macrostructured supporter is at least one of the group consisting of a metal fiber, a carbon felt, a honeycomb ceramic monolith, a silicon-carbide foam, a mulite, an alumina, or composites thereof.The catalyst, according to any one of claims 22 to 27, wherein said active component is in a mass percentage of 2 % to 25 % in relation to the overall mass of said catalyst.The catalyst, according to any one of claims 22 to 29, wherein said macrostructured supporter is in a mass percentage of 75 % to 98 % in relation to the overall mass of said catalyst.A method for preparing the catalyst for heterogeneous catalytic ozonation and / or for heterogeneous catalytic reduction, as defined in any one of claims 22 to 29,characterized in thatsaid method comprises the following steps:a) performing particle size reduction of the active component, obtaining milled particles of the active component; andb) mixing the milled particles of the active component with a liquid vehicle, obtaining a suspension or a slurry of the active component; andc) adsorbing the active component of the suspension or a slurry of the active component in a macrostructured supporter, obtaining a macrostructured supporter coated by an active component; andd) calcinating the macrostructured supporter coated by an active component, obtaining the catalyst for heterogeneous catalytic ozonation and / or for heterogeneous catalytic reduction.The method for preparing the catalyst for heterogeneous catalytic ozonation, according to the previous claim,whereinat least one of a surfactant or a binder is mixed withthe milled particles of the active component and the liquid vehicle in step b).The method for preparing the catalyst for heterogeneous catalytic ozonation, according to any one of claims 30 to 31,whereinthe adsorbing in step c) is executed by dip coating the macrostructured supporter in the suspension or in the slurry of the active component vehicle.A method for preparing the catalyst for heterogeneous catalytic ozonation and / or for heterogeneous catalytic reduction, as defined in any one of claims 22 to 29, characterized in that said method comprises the following steps:a) preparing a liquid solution of a precursor of the active component; andb) contacting the liquid solution of the previous step with a macrostructured supporter, and adsorbing the precursor of the active component in the macrostructured supporter, obtaining a macrostructured supporter coated by a precursor of the active component; andc) executing a thermal treatment of the macrostructured supporter coated by the precursor of the active component, obtaining the catalyst for heterogeneous catalytic ozonation and / or for heterogeneous catalytic reduction.

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