Catalytic ceramic membrane, and preparation method therefor and use thereof

Abstract

Provided are a catalytic ceramic membrane, and a preparation method therefor and the use thereof. The catalytic ceramic membrane comprises a ceramic base membrane and a catalyst loaded on the ceramic membrane, wherein the catalyst comprises metal elements of Ti, Mn and Fe, and the ceramic base membrane comprises at least one of metal elements of Zr, Ti and Al. The catalytic ceramic membrane is used for the preparation of H2O2, has relatively high capability of utilizing oxygen in the air for activation, and generates hydrogen peroxide by means of air aeration without the need for inputting an additional energy (such as light and electricity), such that the generation efficiency of H2O2 is high.

Description

A catalytic ceramic membrane and its preparation method and application Technical Field

[0001] The present invention belongs to the technical field of hydrogen peroxide preparation, and in particular relates to a catalytic ceramic membrane and a preparation method and application thereof. Background Art

[0002] Hydrogen peroxide (H2O2) is one of the most important basic chemicals in modern chemical engineering, energy, and environmental applications. Its traditional preparation method is usually produced through the anthraquinone process, which is energy-intensive and waste-intensive. This traditional anthraquinone process produces a large amount of harmful substances and requires very high transportation and storage costs. While electro- and photocatalytic technologies for in-situ activation of O2 to produce H2O2 have gradually replaced the anthraquinone process, they still require a large amount of electrical and light energy. Currently, heterogeneous catalysts are used to activate O2 to produce H2O2 through charge transfer. However, the current method using conventional heterogeneous catalysts has low H2O2 production efficiency, which has to some extent hindered the development of hydrogen peroxide preparation.

[0003] Summary of the Invention

[0004] The present invention aims to address at least one of the technical problems existing in the aforementioned prior art. To this end, the present invention proposes a catalytic ceramic membrane for use in the production of H2O2. The membrane exhibits high activation capacity and can effectively utilize oxygen in the air for activation. This membrane enables the production of hydrogen peroxide through air aeration without the need for external energy input (such as light or electricity), resulting in high H2O2 production efficiency.

[0005] The invention also provides a method for preparing the catalytic ceramic membrane.

[0006] The present invention also provides a ceramic membrane component.

[0007] The invention also provides a reaction device.

[0008] The present invention also proposes the application of the above-mentioned catalytic ceramic membrane, ceramic membrane assembly or reaction device.

[0009] The present invention also proposes the use of the above-mentioned catalytic ceramic membrane for the preparation of H2O2.

[0010] The invention also provides a method for treating water containing pollutants.

[0011] In a first aspect of the present invention, a catalytic ceramic membrane is proposed, comprising a ceramic base membrane and a catalyst supported on the ceramic membrane, wherein the catalyst comprises metal elements Ti, Mn and Fe, and the ceramic base membrane comprises at least one of the metal elements Zr, Ti or Al.

[0012] The catalytic ceramic membrane according to the embodiment of the present invention has at least the following beneficial effects:

[0013] In the present invention, multi-catalysts such as manganese, iron, and titanium are loaded into a ceramic membrane containing metal elements. By inducing charge redistribution and adjusting the electronic structure, a large number of effective active sites are obtained, thereby solving the problems of single catalytic sites and poor redox ability, and enhancing the ability of the ceramic membrane to activate oxygen.

[0014] The catalytic ceramic membrane of the present invention is used in the production of H2O2. Because the zirconium, titanium, manganese, and iron-containing catalytic ceramic membrane has a high affinity for oxygen, it can be effectively activated by oxygen in the air. The uniform distribution of catalytic sites within the membrane pores enhances the mass transfer efficiency between oxygen and the catalytic sites. This allows for the production of H2O2 using oxygen, or even air aeration, without the need for external energy input (such as light or electricity), resulting in high H2O2 production efficiency. The catalytic ceramic membrane can also activate the generated hydrogen peroxide to generate active species, degrading organic pollutants in water, purifying the water while mitigating membrane fouling.

[0015] Furthermore, the catalytic ceramic membrane of the present invention incorporates catalysts containing titanium, iron, manganese, and the like onto a ceramic-based membrane (e.g., a zirconium-titanium-based ceramic membrane) for easy recycling. In some embodiments of the present invention, the ceramic-based membrane is a nanoporous ceramic membrane, and the catalyst is loaded onto the surface of the ceramic-based membrane and / or within the membrane pores.

[0016] The present invention is based on membrane-based nanotechnology, and the O2 molecules and catalyst can be locally confined in a nanoreactor (such as catalytic ceramic membrane pores, membrane surface) to react. The reaction kinetics induced in the nanoreactor will be much faster than the reaction kinetics of the catalyst and O2 in the bulk suspension liquid, achieving efficient H2O2 production efficiency. In particular, the catalytic ceramic membrane catalyzes O2 molecules to produce H2O2, which can be applied to environmental water treatment and degradation of organic pollutants. At the same time, it can slow down membrane pollution and realize the in-situ self-cleaning function of the membrane. Therefore, in order to solve the problems of high energy consumption in conventional H2O2 production processes and the difficulty of recycling and reusing conventional powder catalysts during application, the present invention loads high-efficiency catalysts into nanoporous ceramic membranes to enhance the mass transfer of local O2 and promote the efficient generation of H2O2, thereby broadening its application in water treatment.

[0017] In some embodiments of the present invention, the catalytically active components of the catalytic ceramic membrane include the elements zirconium, titanium, iron and manganese.

[0018] The present invention proposes the use of a catalytic ceramic membrane containing zirconium, titanium, manganese and iron with high oxygen affinity, wherein the combination of a catalyst containing transition metal elements and a ceramic base membrane improves the utilization efficiency of catalytic sites, improves the ability to activate oxygen, and enhances the mass transfer efficiency between O2 and catalytic sites in the membrane pores, thereby achieving the production of hydrogen peroxide using oxygen in the air without the need for external energy (such as light or electricity) input.

[0019] In some embodiments of the present invention, the ceramic-based membrane includes but is not limited to a zirconium-titanium-based ceramic membrane, an aluminum-based ceramic membrane, a zirconium-based ceramic membrane, a titanium-based ceramic membrane, etc. Optionally, the ceramic-based membrane includes a zirconium-titanium ceramic membrane or an aluminum-based ceramic membrane.

[0020] The active components of the catalytic ceramic membrane of the present invention include elements such as Zr, Al, Mn, Fe, Ti, etc., which are abundant in the earth. The raw materials are widely available, the preparation cost is low, and the cost of producing hydrogen peroxide is low.

[0021] In the present invention, the catalyst is loaded into a ceramic-based membrane (such as a zirconium-titanium-based ceramic membrane, an aluminum-based ceramic membrane), and its active components also include the metal elements contained in the ceramic-based membrane (such as Zr, Ti and Al elements). Multi-metal electron transfer and other processes occur between the catalyst and the catalyst. By inducing charge redistribution and adjusting the electronic structure, a large number of effective active sites are obtained, thereby solving the problems of single catalytic sites and poor redox ability, and enhancing the ability of the catalytic ceramic membrane to activate oxygen.

[0022] In some embodiments of the present invention, in the catalyst, the molar ratio of elements Ti, Mn and Fe is (0.1-1):(1-3):(1-3).

[0023] In some embodiments of the present invention, the catalyst comprises Ti, Mn3O4 and Fe3O4.

[0024] In some embodiments of the present invention, in the catalyst, the molar ratio of Ti, Mn3O4 and Fe3O4 is (0.1-1):(0.3-1):(0.3-1).

[0025] In some embodiments of the present invention, oxygen vacancy structures are distributed in the catalyst.

[0026] In some embodiments of the present invention, the catalyst is in granular form, with an average particle size of 5-50 nm, optionally 10-20 nm.

[0027] In some embodiments of the present invention, the mass ratio of the catalyst to the ceramic-based membrane is 1:(700-1200), and can be optionally 1:999.

[0028] In some embodiments of the present invention, the components of the ceramic-based membrane include ZrO2 and TiO2.

[0029] In some embodiments of the present invention, the thickness of the ceramic base membrane is 1.5-5 mm, and can be 2.5 mm.

[0030] In some embodiments of the present invention, the thickness of the catalytic ceramic membrane is 1.2-4.9 mm, and can be 2.5 mm.

[0031] The second aspect of the present invention proposes a method for preparing a catalytic ceramic membrane, comprising the following steps: using a ceramic base membrane as a filter membrane, filtering the catalyst precursor liquid to obtain a filtrate and a ceramic base membrane after filtration, and obtaining the catalytic ceramic membrane through a hydrothermal reaction.

[0032] In some embodiments of the present invention, the preparation method comprises the following steps:

[0033] S1: Using a ceramic-based membrane as a filter membrane, vacuum filtration is performed on the catalyst precursor liquid to obtain a filtrate and a ceramic-based membrane after filtration;

[0034] S2: placing the filtrate obtained in step S1 and the ceramic base membrane in a reaction container, subjecting them to a hydrothermal reaction to obtain a catalytic ceramic membrane precursor, and calcining them to obtain the catalytic ceramic membrane.

[0035] In some embodiments of the present invention, in step S1, the vacuum degree of vacuum filtration is 0.01-0.2 MPa; optionally 0.01-0.15 MPa.

[0036] In some embodiments of the present invention, in step S1, the vacuum degree of vacuum filtration is 0.05-0.15 MPa.

[0037] In some embodiments of the present invention, in step S1, the vacuum degree of vacuum filtration is 0.01-0.08 MPa.

[0038] In some embodiments of the present invention, in step S1, the vacuum degree of vacuum filtration is 0.02-0.1 MPa.

[0039] In some embodiments of the present invention, in step S1, the ceramic-based membrane may be selected from a zirconium-titanium-based ceramic membrane, an aluminum-based ceramic membrane, a zirconium-based ceramic membrane, or a titanium-based ceramic membrane.

[0040] In some embodiments of the present invention, in step S2, the reaction temperature of the hydrothermal reaction is 100-200° C., and the reaction time is 6-36 hours.

[0041] In some embodiments of the present invention, in step S2, the catalytic ceramic membrane precursor is dried and then calcined.

[0042] In some embodiments of the present invention, the drying step comprises drying the catalytic ceramic membrane precursor at 80-100° C. for 8-12 hours.

[0043] In some embodiments of the present invention, the calcination temperature is 200-1000°C, optionally 300-1000°C.

[0044] In some embodiments of the present invention, the calcination time is 2-10 hours, and optionally 2-6 hours.

[0045] In some embodiments of the present invention, step S2 includes: placing the filtrate obtained in step S1 and the ceramic base membrane in an autoclave, heating to 100-200°C and continuing the reaction for 6-36 hours to obtain a catalytic ceramic membrane precursor, drying at 80-100°C for 8-12 hours, and then calcining at 300-1000°C for 2-6 hours to obtain the catalytic ceramic membrane.

[0046] In some embodiments of the present invention, the preparation method further comprises preparing a precursor liquid of the catalyst, which specifically comprises the following operations: taking a titanium source, a manganese source and an iron source, and obtaining the precursor liquid of the catalyst under alkaline conditions.

[0047] In some embodiments of the present invention, the titanium source includes at least one of a titanium salt or tetrabutyl titanate.

[0048] In some embodiments of the present invention, the titanium salt comprises titanium sulfate.

[0049] In some embodiments of the present invention, the manganese source comprises a manganese salt.

[0050] In some embodiments of the present invention, the manganese salt comprises at least one of manganese nitrate or potassium permanganate.

[0051] In some embodiments of the present invention, the iron source comprises an iron salt.

[0052] In some embodiments of the present invention, the iron salt includes at least one of ferric nitrate, ferric sulfate and hydrates thereof.

[0053] In some embodiments of the present invention, the molar ratio of the element Ti in the titanium source, the element Mn in the manganese source, and the element Fe in the iron source is (0.05-1):(1-3):(1-3).

[0054] In some embodiments of the present invention, preparing the catalyst precursor liquid specifically includes the following operations: mixing a first solution containing a titanium source, a manganese source, and an iron source with a second solution containing an alkaline substance, and stirring to obtain the catalyst precursor liquid.

[0055] In some embodiments of the present invention, preparing the catalyst precursor liquid specifically includes the following operations:

[0056] S0-1: mixing a titanium source, a manganese source, an iron source and water to obtain the first solution;

[0057] mixing an alkaline substance with water to obtain the second solution;

[0058] S0-2: The first solution and the second solution are mixed and stirred to obtain a precursor liquid of the catalyst.

[0059] In some embodiments of the present invention, in step S0-1, the alkaline substance includes at least one of ammonium hydroxide, sodium hydroxide or potassium hydroxide.

[0060] In some embodiments of the present invention, in step S0-1, the sum of the mass fractions of the titanium source, the manganese source and the iron source in the first solution is 35-65%.

[0061] In some embodiments of the present invention, in step S0-1, the first solution further includes a coprecipitant.

[0062] In some embodiments of the present invention, the coprecipitant comprises at least one of polyvinyl pyrrolidone or polyethylene glycol.

[0063] In some embodiments of the present invention, in step S0-2, the stirring time is 1-6 hours.

[0064] The preparation method of the catalytic ceramic membrane of the present invention has a wide range of raw material sources, low cost, no need for complex operation control in the production process, mild reaction conditions, and no need for expensive equipment, which is conducive to industrial large-scale production.

[0065] The third aspect of the present invention provides a ceramic membrane assembly comprising the above-mentioned catalytic ceramic membrane.

[0066] In some embodiments of the present invention, the ceramic membrane assembly further includes a shell and a reaction cavity formed in the shell, and the catalytic ceramic membrane is located in the reaction cavity.

[0067] In some embodiments of the present invention, the ceramic membrane assembly includes an air inlet pipeline, a liquid inlet pipeline, and a discharge pipeline, all of which are connected to the reaction chamber.

[0068] In some embodiments of the present invention, the housing includes a top cover, a connecting wall, and a bottom cover, and the top cover and the bottom cover are connected by the connecting wall to form the reaction chamber.

[0069] In some embodiments of the present invention, the liquid inlet pipeline and the material outlet pipeline are respectively arranged on both sides of the catalytic ceramic membrane.

[0070] In some embodiments of the present invention, the liquid inlet pipeline and the air inlet pipeline are located on the same side of the catalytic ceramic membrane.

[0071] In some embodiments of the present invention, the air inlet pipeline and the liquid inlet pipeline are arranged at the bottom of the shell, and the discharge pipeline is arranged at the top.

[0072] Optionally, when the housing includes a top cover, a connecting wall, and a bottom cover, the liquid inlet pipeline and the air inlet pipeline may be connected to the connecting wall or the bottom cover, and the discharge pipeline may be connected to the connecting wall or the top cover. The discharge pipeline is located above the liquid inlet pipeline and the air inlet pipeline.

[0073] In a fourth aspect of the present invention, a reaction device is provided, comprising a reactor, wherein the reactor is the above-mentioned ceramic membrane assembly.

[0074] In some embodiments of the present invention, a flow meter is provided on the air intake pipeline.

[0075] In some embodiments of the present invention, a pressure gauge is installed on the discharge pipeline.

[0076] In some embodiments of the present invention, the reactor further comprises a liquid inlet reservoir and a material discharge reservoir, wherein the liquid inlet reservoir is in communication with the liquid inlet pipeline, and the material discharge reservoir is in communication with the material discharge pipeline.

[0077] In some embodiments of the present invention, the material in the liquid inlet reservoir is optionally transported to the reactor via the liquid inlet pipeline by a peristaltic pump; and / or, the material in the reactor is optionally transported to the discharge reservoir via the discharge pipeline by a peristaltic pump.

[0078] The fifth aspect of the present invention proposes the use of the above-mentioned catalytic ceramic membrane, ceramic membrane assembly, and reaction device in the preparation of H2O2, degradation of organic pollutants or water treatment.

[0079] The catalytic ceramic membrane of the present invention has a high ability to be activated by oxygen in the air. The catalytic sites are evenly distributed within the membrane pores, enhancing the mass transfer efficiency between the oxygen in the membrane pores and the catalytic sites. This allows the production of hydrogen peroxide using air aeration without the need for external energy input (such as light or electricity). The catalytic ceramic membrane can also activate the generated hydrogen peroxide to generate active species, degrading organic pollutants in water, purifying the water while mitigating membrane fouling. Furthermore, because the catalyst in the catalytic ceramic membrane of the present invention is fixed to the surface of the ceramic base membrane, the problem of catalyst recycling is resolved, providing an environmentally friendly method for producing hydrogen peroxide.

[0080] The sixth aspect of the present invention proposes the use of placing the above-mentioned catalytic ceramic membrane in a system containing water and oxygen to prepare H2O2.

[0081] In some embodiments of the present invention, the preparation of H2O2 comprises the following steps: mixing a reaction gas containing oxygen with a solution containing water, and obtaining H2O2 through the catalytic action of the catalytic ceramic membrane.

[0082] The preparation of H2O2 according to the embodiment of the present invention has at least the following beneficial effects:

[0083] The catalytic ceramic membrane of the present invention has a high affinity for oxygen and a high ability to be activated by oxygen in the air. The catalytic sites are evenly distributed in the membrane pores, which can enhance the mass transfer efficiency between the oxygen in the membrane pores and the catalytic sites, thereby achieving the production of hydrogen peroxide using oxygen or even air aeration without the need for external energy (such as light or electricity) input.

[0084] In some embodiments of the present invention, the concentration of hydrogen peroxide in the outlet water of the H2O2 production equipment is monitored to determine and calculate the production efficiency of hydrogen peroxide.

[0085] In some embodiments of the present invention, the reaction gas is oxygen or air, preferably air.

[0086] In some embodiments of the present invention, the aqueous solution is water.

[0087] In a seventh aspect of the present invention, a method for treating a water body containing pollutants is proposed, comprising the following steps: placing the above-mentioned catalytic ceramic membrane in the water body.

[0088] In some embodiments of the present invention, the treatment method includes the following steps: mixing a reaction gas containing oxygen with the water body, and removing pollutants in the water body through the action of the catalytic ceramic membrane.

[0089] The water treatment method according to the embodiment of the present invention has at least the following beneficial effects:

[0090] When the catalytic ceramic membrane of the present invention is used to treat water bodies containing pollutants, the abundant catalytic sites such as zirconium, titanium, iron and manganese in the catalytic ceramic membrane react with O2 molecules in the membrane pores to generate hydrogen peroxide. These catalytic sites further catalyze the hydrogen peroxide to produce strongly oxidizing free radicals and non-free radical species, which attack the pollutant molecules in the membrane pores, thereby achieving the degradation function of pollutants (such as emerging pollutants), thereby degrading organic pollutants in the water, purifying the water quality and alleviating membrane pollution.

[0091] In some embodiments of the present invention, the concentration of pollutants in the inlet and outlet water of the water treatment is monitored to determine and calculate the removal status of pollutants in the water.

[0092] In some embodiments of the present invention, the reaction gas is oxygen or air, preferably air.

[0093] In some embodiments of the present invention, the water body containing pollutants includes but is not limited to surface water, tap water, domestic sewage, medical wastewater, etc.

[0094] In some embodiments of the present invention, the water body is wastewater, which can be medical wastewater.

[0095] In the process of removing pollutants from pharmaceutical wastewater, the catalytic ceramic membrane of the present invention reacts with O2 molecules in the membrane pores to generate hydrogen peroxide due to the abundant catalytic sites such as zirconium, titanium, iron and manganese in the catalytic ceramic membrane. These catalytic sites further catalyze the hydrogen peroxide to produce highly oxidizing free radicals and non-free radical species, which attack various pollutant molecules (such as emerging pollutants) in the membrane pores, thereby achieving the degradation function of various pollutants in actual water bodies.

[0096] In some embodiments of the present invention, the removal of emerging pollutants in pharmaceutical wastewater can be determined and calculated by monitoring the concentrations of various emerging pollutants in the inlet and outlet water of water treatment.

[0097] In some embodiments of the present invention, when not treated by the treatment method, the total concentration of pollutants in the wastewater is above 300 μg / L.

[0098] In some embodiments of the present invention, the total concentration of pollutants in the wastewater is 300-1000 μg / L before being treated by the treatment method.

[0099] In some embodiments of the present invention, after the wastewater is treated by the treatment method, the total concentration of pollutants contained in the wastewater is below 150 μg / L.

[0100] In some embodiments of the present invention, after the wastewater is treated by the treatment method, the total concentration of pollutants contained in the wastewater is 5-150 μg / L.

[0101] In some embodiments of the present invention, the pollutant includes at least one of ofloxacin, ciprofloxacin, tiamulin, paracetamol, bezafibrate, bisphenol A, octylphenol, estradiol, estrone, ethinyl estradiol, salicylic acid, diclofenac, ibuprofen, indomethacin, theophylline, caffeine, sulfapyridine, atenolol, pirenzepine, metoprolol, sulfamethoxazole, erythromycin, tetracycline, trimethoprim-pyridine, DEET, oxytetracycline, roxithromycin, crotamiton, clarithromycin, carbamazepine, azithromycin or ifenprodil.

[0102] In some embodiments of the present invention, the treatment method further comprises the step of cleaning the catalytic ceramic membrane.

[0103] In some embodiments of the present invention, the step of cleaning the catalytic ceramic membrane includes the following operations: in the process of treating wastewater, water is used instead of medical wastewater to clean the membrane assembly.

[0104] In some embodiments of the present invention, the treatment method comprises the following steps:

[0105] Sa-1: The wastewater is pumped into the membrane module and exposed to air or oxygen. The pollutants in the wastewater are treated by the catalytic ceramic membrane for a treatment time of t1.

[0106] Sa-2: Water is used instead of medical wastewater to be pumped into the membrane assembly, and air or oxygen is introduced. H2O2 is generated by the action of the catalytic ceramic membrane to clean the catalytic ceramic membrane. The cleaning time is t2.

[0107] In some embodiments of the present invention, t1 is 20-40 min, and / or t2 is 5-15 min.

[0108] In some embodiments of the present invention, the treatment method further comprises step Sa-3: alternately repeating step Sa-1 and step Sa-2 3-10 times.

[0109] In some embodiments of the present invention, in the wastewater treatment method, the cleaning effect of the catalytic ceramic membrane is determined by monitoring the change in the membrane flux of the catalytic ceramic membrane during the treatment process.

[0110] Through the above-described embodiment, the self-cleaning effect of the catalytic ceramic membrane is determined by monitoring changes in the membrane flux of the catalytic ceramic membrane during membrane filtration. Specifically, when the catalytic ceramic membrane of the present invention is used to filter actual pharmaceutical wastewater, the abundant catalytic sites such as zirconium, titanium, iron, and manganese in the catalytic ceramic membrane react with O2 molecules in the membrane pores to generate hydrogen peroxide. These catalytic sites further catalyze the hydrogen peroxide to produce highly oxidizing free radicals and non-free radical species. These sites have the function of degrading organic pollutants trapped on the membrane surface during the filtration of pharmaceutical wastewater, as well as various emerging pollutants in the pharmaceutical wastewater, thereby maintaining a constant membrane flux and achieving a self-cleaning function. BRIEF DESCRIPTION OF THE DRAWINGS

[0111] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0112] FIG1 is a surface scanning electron microscope image of the catalytic ceramic membrane in Example 1 of the present invention;

[0113] FIG2 is a scanning electron microscope image of a cross section of the catalytic ceramic membrane in Example 1 of the present invention;

[0114] FIG3 is a photograph of the catalytic ceramic membrane in Example 1 of the present invention;

[0115] FIG4 is a schematic structural diagram of the reaction apparatus in Example 2 of the present invention;

[0116] FIG5 is a graph showing the test results of hydrogen peroxide production at different membrane fluxes in Example 2 of the present invention;

[0117] FIG6 is a graph showing the test results of hydrogen peroxide generation at different air flow rates in Example 3 of the present invention;

[0118] FIG7 is a graph showing the test results of H2O2 produced by the system at different catalyst amounts in Comparative Example 1;

[0119] FIG8 is a graph showing the test results of hydrogen peroxide production using air aeration in Example 2, Comparative Example 2, Comparative Example 8, Comparative Example 10, and Comparative Example 12 of the present invention;

[0120] FIG9 is a graph showing the test results of ofloxacin degradation in wastewater at different air flow rates in Example 4 of the present invention;

[0121] FIG10 is a graph showing the test results of catalytic degradation of emerging pollutants in pharmaceutical wastewater using air aeration in Example 5 of the present invention and Comparative Example 3;

[0122] FIG11 is a graph showing the test results of catalytic degradation of emerging pollutants in pharmaceutical wastewater using pure oxygen aeration in Example 6 of the present invention and Comparative Example 4;

[0123] FIG12 is a graph showing the membrane flux variation results of filtering medical wastewater using air aeration in Example 7 of the present invention and Comparative Example 5;

[0124] FIG13 is a graph showing the membrane flux variation results of filtering pharmaceutical wastewater using pure oxygen aeration in Example 8 of the present invention and Comparative Example 6. DETAILED DESCRIPTION

[0125] The following will clearly and completely describe the concept and technical effects of the present invention in conjunction with the embodiments to fully understand the purpose, features and effects of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, other embodiments obtained by those skilled in the art without creative work are all within the scope of protection of the present invention.

[0126] The experimental methods in the following examples, for which specific conditions are not specified, are generally performed in accordance with conventional conditions in the art or conditions recommended by the manufacturers; the raw materials and reagents used, unless otherwise specified, are all commercially available from conventional markets.

[0127] Zirconium-titanium ceramic membrane, a ceramic ultrafiltration membrane; composition = ZrO2 and TiO2; thickness = 2.5 mm; diameter = 47 mm; molecular weight cutoff (MWCO) = 300 kDa, purchased from Sterlitech (USA), model 47U300.

[0128] Example 1

[0129] This embodiment discloses a catalytic ceramic membrane having a thickness of approximately 2.5 mm and comprising a ceramic base membrane and a catalyst supported on the ceramic base membrane. The catalyst is 0.5Ti-Mn3O4 / Fe3O4, wherein the mass ratio of the catalyst to the ceramic base membrane is approximately 1:999, and the particle size of the catalyst particles is approximately 10-50 nm. The preparation reaction process of the catalytic ceramic membrane includes the following steps:

[0130] (I) Appropriate amounts of 50% manganese nitrate solution, ferric sulfate heptahydrate, and titanium sulfate were weighed and dissolved in 30 mL of pure water to form a first solution. 200 mg of sodium hydroxide was weighed and dissolved in 10 mL of pure water to form a second solution. The molar ratio of elemental titanium in the titanium sulfate, elemental manganese in the manganese nitrate, and elemental iron in the ferric sulfate was 0.5:1:1.

[0131] (II) The first solution and the second solution were stirred at room temperature for 1 h to form a mixed suspension liquid.

[0132] (III) The zirconium-titanium ceramic membrane is used as a filter membrane, and the mixed suspension liquid is vacuum filtered in the zirconium-titanium ceramic membrane at a filtration pressure of 0.08 MPa.

[0133] (IV) The ceramic membrane obtained after the filtration and the filtered filtrate were then transferred to a polytetrafluoroethylene liner, sealed in a reactor, and mixed and hydrothermaled in an oven at 100° C. for 24 h.

[0134] (V) After the reaction is completed and the mixture is cooled to room temperature, the obtained ceramic membrane is dried in an oven at 80°C for 12 hours and then calcined in a muffle furnace at 300°C for 2 hours to obtain a zirconium-titanium-manganese-iron catalytic ceramic membrane.

[0135] This embodiment also discloses a ceramic membrane assembly, comprising the catalytic ceramic membrane produced in this embodiment, a housing, and a reaction chamber formed within the housing. The catalytic ceramic membrane is located within the reaction chamber, and the ceramic membrane assembly is provided with an air inlet line, a liquid inlet line, and a discharge line connected to the reaction chamber. The air inlet line and liquid inlet line are provided at the bottom of the housing, and the discharge line is provided at the top. The liquid inlet line and the discharge line are respectively provided on either side of the catalytic ceramic membrane. The liquid inlet line and the air inlet line are located on the same side of the catalytic ceramic membrane, and the catalytic ceramic membrane is located above the liquid inlet line. The catalytic ceramic membrane is fixed within the membrane assembly.

[0136] Optionally, the shell includes a top cover, a connecting wall and a bottom cover, the top cover and the bottom cover are connected by the connecting wall to form a reaction chamber, the liquid inlet pipeline is connected to the connecting wall, the top cover is provided with a discharge pipeline, the bottom cover is provided with an air inlet pipeline, and the shell is sealed tightly with an O-ring rubber band, such as sealing the top cover and the connecting wall, and the bottom cover and the connecting wall to prevent water leakage.

[0137] This embodiment also discloses a reaction device, a schematic structural diagram of which is shown in Figure 4, including a reactor, and the reactor is a ceramic membrane assembly in this embodiment. The reaction device also includes a liquid inlet reservoir and a discharge reservoir, the liquid inlet reservoir is connected to the liquid inlet pipeline, and the discharge reservoir is connected to the discharge pipeline. The material in the liquid inlet reservoir can be optionally transported to the reactor via the liquid inlet pipeline by a peristaltic pump. The material in the reactor can be optionally transported to the discharge reservoir via the discharge pipeline by a peristaltic pump. Optionally, a flow meter is provided on the air inlet pipeline, and a pressure gauge is provided on the discharge pipeline (the transmembrane pressure is recorded by the pressure gauge).

[0138] Example 2

[0139] This embodiment discloses a method for preparing hydrogen peroxide, which uses the reaction apparatus and / or ceramic membrane assembly of Example 1 and air aeration at different membrane fluxes to produce hydrogen peroxide, including the following steps:

[0140] Ionized water was pumped into the ceramic membrane assembly, and air was exposed to it at a flow rate of 100 mL / min. The water flux was adjusted to 20, 40, 60, 80 and 100 L / m 2 / h, hydrogen peroxide is produced in the reaction system, and the production of hydrogen peroxide in the membrane effluent is measured.

[0141] Example 3

[0142] This embodiment discloses a method for preparing hydrogen peroxide, which uses the reaction device and / or ceramic membrane assembly of Example 1 and air aeration at different air flow rates to produce hydrogen peroxide, including the following steps:

[0143] Ionized water was pumped into the ceramic membrane assembly, and air was exposed to it at flow rates of 0, 100, 150, 200, 300, 400 and 500 mL / min, respectively, to adjust the water flux to 40 L / m 2 / h, hydrogen peroxide is produced in the reaction system, and the production of hydrogen peroxide in the membrane effluent is measured.

[0144] Example 4

[0145] This embodiment discloses a wastewater treatment method, which uses the reaction device and / or ceramic membrane assembly of Example 1 to perform an experiment to degrade the emerging pollutant ofloxacin using air aeration at different air flow rates, including the following steps:

[0146] A 5 mg / L ofloxacin aqueous solution was pumped into the ceramic membrane assembly, and air was exposed to it at flow rates of 0, 100, 200, 300, 400 and 500 mL / min, respectively, to adjust the water flux to 40 L / m 2 / h, ofloxacin was degraded in the reaction system, and the concentration of ofloxacin in the membrane effluent was measured.

[0147] Example 5

[0148] This embodiment discloses a wastewater treatment method, which uses the reaction device and / or ceramic membrane assembly of Example 1 and air aeration to catalytically remove various emerging pollutants in pharmaceutical wastewater, including the following steps:

[0149] The pharmaceutical wastewater was pumped into the ceramic membrane assembly and air was introduced at a flow rate of 150 mL / min to adjust the water flux to 40 L / m 2 / h, catalytically degrade emerging pollutants in pharmaceutical wastewater in this reaction system, and measure the concentration changes of various emerging pollutants during membrane filtration.

[0150] Example 6

[0151] This embodiment discloses a wastewater treatment method, which uses the reaction device and / or ceramic membrane assembly of Example 1 and pure oxygen aeration to catalytically remove various emerging pollutants in pharmaceutical wastewater, including the following steps:

[0152] The pharmaceutical wastewater was pumped into the ceramic membrane assembly and oxygen was introduced at a flow rate of 150 mL / min. The water flux was adjusted to 40 L / m 2 / h, catalytically degrade emerging pollutants in pharmaceutical wastewater in this reaction system, and measure the concentration changes of various emerging pollutants during membrane filtration.

[0153] Example 7

[0154] This embodiment discloses a wastewater treatment method, which uses the reaction device and / or ceramic membrane assembly of Example 1 and air aeration to perform catalytic filtration of various emerging pollutants in pharmaceutical wastewater, including the following steps:

[0155] The pharmaceutical wastewater was pumped into the ceramic membrane assembly and air was introduced at a flow rate of 150 mL / min to adjust the water flux to 40 L / m 2 / h, catalytically filtering pharmaceutical wastewater in the reaction system. Including:

[0156] Pollutant treatment steps: The water inlet pump (installed in the liquid inlet pipeline) pumps the medical wastewater into the membrane module and exposes it to air for 30 minutes, that is, the membrane filtration time is selected to be 30 minutes;

[0157] Cleaning step: After the pollutant treatment step, deionized water was used instead of the pharmaceutical wastewater. The inlet pump pumped deionized water into the membrane module and simultaneously exposed it to air for 10 minutes, i.e., a 10-minute cleaning period. Five cycles of the pollutant treatment step followed by the cleaning step (30 minutes of filtration followed by 10 minutes of cleaning) were performed, and changes in membrane flux during the filtration process were measured.

[0158] Example 8

[0159] This embodiment discloses a wastewater treatment method. By using the reaction device and / or ceramic membrane assembly in Example 1, pure oxygen aeration is used to conduct catalytic filtration experiments on various emerging pollutants in pharmaceutical wastewater. The difference between this embodiment and Example 7 is that oxygen is used instead of air in Example 7, the gas aeration flow rate is 150 mL / min, and other conditions are the same.

[0160] Example 7.

[0161] Comparative Example 1

[0162] This comparative example discloses a method for preparing hydrogen peroxide, which uses a ternary catalyst instead of a zirconium-titanium-manganese-iron catalytic ceramic membrane and uses air aeration to produce hydrogen peroxide at different catalyst dosages, comprising the following steps:

[0163] 100 mL of deionized water was placed in a beaker. An appropriate amount of a ternary catalyst (0.5 Ti-Mn3O4 / Fe3O4) (catalyst dosage: 200 mg / L, 400 mg / L, 600 mg / L, 800 mg / L, 1000 mg / L) was added to the beaker. Air was introduced at a flow rate of 100 mL / min to generate hydrogen peroxide in the reaction system. The amount of hydrogen peroxide produced in the water was measured over a certain period of time.

[0164] Comparative Example 2

[0165] This comparative example discloses a method for preparing hydrogen peroxide. The difference between this comparative example and Example 2 is that the ceramic membrane in the reaction device and / or ceramic membrane assembly used in this comparative example is different from that in Example 2. In this comparative example, a zirconium-titanium ceramic membrane is used to replace the zirconium-titanium-manganese-iron catalytic ceramic membrane in Example 2. At the same time, the membrane flux in this comparative example is 40 L / m 2 / h, and the rest is the same as in Example 2.

[0166] Comparative Example 3

[0167] This comparative example discloses a wastewater treatment method. This method differs from Example 5 in that the reaction apparatus and / or ceramic membrane in the ceramic membrane assembly used in this comparative example are different from those in Example 5. In this comparative example, a zirconium-titanium-manganese-iron catalytic ceramic membrane is used in place of the zirconium-titanium-manganese-iron catalytic ceramic membrane in Example 5. The remaining contents are the same as in Example 5.

[0168] Comparative Example 4

[0169] This comparative example discloses a wastewater treatment method. This method differs from Example 6 in that the reaction apparatus and / or ceramic membrane in the ceramic membrane assembly used in this comparative example are different from those in Example 6. In this comparative example, a zirconium-titanium-manganese-iron catalytic ceramic membrane is used in place of the zirconium-titanium-manganese-iron catalytic ceramic membrane in Example 6. The remaining contents are the same as in Example 6.

[0170] Comparative Example 5

[0171] This comparative example discloses a wastewater treatment method. This method differs from Example 7 in that the reaction apparatus and / or ceramic membrane in the ceramic membrane assembly used in this comparative example are different from those in Example 7. In this comparative example, a zirconium-titanium-manganese-iron catalytic ceramic membrane is used in place of the zirconium-titanium-manganese-iron catalytic ceramic membrane in Example 7. The remaining contents are the same as in Example 7.

[0172] Comparative Example 6

[0173] This comparative example discloses a wastewater treatment method. This method differs from Example 8 in that the reaction apparatus and / or ceramic membrane in the ceramic membrane assembly used in this comparative example are different from those in Example 8. In this comparative example, a zirconium-titanium-manganese-iron catalytic ceramic membrane is used in place of the zirconium-titanium-manganese-iron catalytic ceramic membrane in Example 8. The remaining contents are the same as in Example 8.

[0174] Comparative Example 7

[0175] This comparative example discloses an iron-based ceramic membrane. This example differs from Example 1 in that step (I) comprises: weighing 0.15 mmol of ferric sulfate heptahydrate and dissolving it in 30 mL of pure water to form a first solution; and weighing 200 mg of sodium hydroxide and dissolving it in 10 mL of pure water to form a second solution. The remaining steps are the same as those in Example 1.

[0176] This comparative example also discloses a ceramic membrane assembly, which differs from Example 1 in that an iron-based ceramic membrane is used in this comparative example to replace the catalytic ceramic membrane in Example 1.

[0177] This comparative example also discloses a reaction device, including a reactor. The reactor is the ceramic membrane assembly in this comparative example, and the rest of the structure is the same as that of Example 1.

[0178] Comparative Example 8

[0179] This comparative example discloses a method for preparing hydrogen peroxide. The difference between this comparative example and Example 2 is that the ceramic membrane in the reaction device and / or ceramic membrane assembly used in this comparative example is the reaction device and / or ceramic membrane assembly obtained in Comparative Example 7, that is, the iron-based ceramic membrane in this comparative example replaces the zirconium-titanium-manganese-iron catalytic ceramic membrane in Example 2. At the same time, the membrane flux in this comparative example is 40 L / m 2 / h, and the rest is the same as in Example 2.

[0180] Comparative Example 9

[0181] This comparative example discloses a manganese-iron-based ceramic membrane. This example differs from Example 1 in that step (I) comprises weighing appropriate amounts of a 50% by mass manganese nitrate solution and ferric sulfate heptahydrate and dissolving them in 30 mL of pure water to form a first solution, and weighing 200 mg of sodium hydroxide and dissolving them in 10 mL of pure water to form a second solution. The molar ratio of elemental manganese in the manganese nitrate to elemental manganese in the ferric sulfate is 1:1. The remaining steps are the same as in Example 1.

[0182] This comparative example also discloses a ceramic membrane assembly, which differs from Example 1 in that a manganese-iron-based ceramic membrane is used in this comparative example to replace the catalytic ceramic membrane in Example 1.

[0183] This comparative example also discloses a reaction device, including a reactor. The reactor is the ceramic membrane assembly in this comparative example, and the rest of the structure is the same as that of Example 1.

[0184] Comparative Example 10

[0185] This comparative example discloses a method for preparing hydrogen peroxide. The difference between this comparative example and Example 2 is that the ceramic membrane in the reaction device and / or ceramic membrane assembly used in this comparative example is the reaction device and / or ceramic membrane assembly obtained in Comparative Example 9, that is, the zirconium-titanium-manganese-iron catalytic ceramic membrane in Example 2 is replaced by a manganese-iron-based ceramic membrane in this comparative example. At the same time, the membrane flux in this comparative example is 40 L / m 2 / h, and the rest is the same as in Example 2.

[0186] Comparative Example 11

[0187] This comparative example discloses a ferrocerium-based ceramic membrane. This example differs from Example 1 in that step (I) comprises weighing appropriate amounts of cerium chloride heptahydrate and ferric chloride hexahydrate and dissolving them in 30 mL of pure water to form a first solution, and weighing 200 mg of sodium hydroxide and dissolving them in 10 mL of pure water to form a second solution. The molar ratio of the metals in the cerium chloride and ferric chloride is 1:1. The remaining steps are the same as in Example 1.

[0188] This comparative example also discloses a ceramic membrane assembly, which differs from Example 1 in that a ferrocerium-based ceramic membrane is used in this comparative example to replace the catalytic ceramic membrane in Example 1.

[0189] This comparative example also discloses a reaction device, including a reactor. The reactor is the ceramic membrane assembly in this comparative example, and the rest of the structure is the same as that of Example 1.

[0190] Comparative Example 12

[0191] This comparative example discloses a method for preparing hydrogen peroxide. The difference between this comparative example and Example 2 is that the ceramic membrane in the reaction device and / or ceramic membrane assembly used in this comparative example is the reaction device and / or ceramic membrane assembly obtained in Comparative Example 11, that is, the ferrocerium-based ceramic membrane in this comparative example replaces the zirconium-titanium-manganese-iron catalytic ceramic membrane in Example 2. At the same time, the membrane flux in this comparative example is 40 L / m 2 / h, and the rest is the same as in Example 2.

[0192] Test example

[0193] This test example tests the catalyst ceramic membranes obtained in the examples and comparative examples, the results of hydrogen peroxide preparation, and the results of wastewater treatment. Specifically, it includes:

[0194] (1) Microstructure test of the zirconium-titanium-manganese-iron catalytic ceramic membrane prepared in Example 1:

[0195] A scanning electron microscope image of the surface of the catalytic ceramic membrane is shown in FIG1 . As can be seen from FIG1 , the surface of the catalytic ceramic membrane prepared by the present invention is relatively uniform and smooth, dense and porous.

[0196] A scanning electron microscope image of the cross-section of the catalytic ceramic membrane is shown in Figure 2. As can be seen from Figure 2, the catalytic ceramic membrane prepared by the present invention includes a dense membrane layer containing ZrO2 and a support layer containing TiO2. The three-way catalyst 0.5Ti-Mn3O4 / Fe3O4 is distributed in the dense layer and the support layer. The dense membrane layer is composed of smaller particles, the support layer particles are larger, and the thickness of the dense membrane layer is about 10μm.

[0197] (2) FIG5 is a graph showing the results of hydrogen peroxide production by air aeration of the catalytic ceramic membrane described in Example 2 at different membrane fluxes. As can be seen from the figure, as the water flux decreases from 100, 80, 60, 40 to 20 L / m 2 / h, the concentration of H2O2 generated in the air activated by the catalytic ceramic membrane increased from 10.4, 17.1, 21.7, 30.5 to 33.0 μmol / L.

[0198] (3) FIG6 is a graph showing the results of hydrogen peroxide production by the catalytic ceramic membrane described in Example 3 using air aeration at different air flow rates. As can be seen from the figure, as the air flow rate increases from 0, 100, 150, 200, 300, 400 to 500 mL / min, the concentration of H2O2 generated in the activated air by the catalytic ceramic membrane increases from 22.3, 30.5, 34.1, 40.2, 43.3, 49.5 to 55.1 μmol / L (wherein, when the air flow rate is 0, the catalytic ceramic membrane uses the dissolved oxygen in the ionized water to generate H2O2; the dissolved oxygen content in the ionized water is the saturated dissolved oxygen concentration of ionized water at room temperature and pressure, which is approximately 8.0-8.1 mg / L).

[0199] (4) FIG7 is a graph showing the test results of H2O2 produced by each system under different amounts of catalyst in Example 1. By comparing with the test results of Examples 2-3 of the present invention, it can be seen that compared with the use of only a three-way catalyst for catalytic production of H2O2, the use of a catalytic ceramic membrane for catalytic production of H2O2 in the present invention is significantly more efficient and has a better catalytic effect.

[0200] (5) FIG8 is a graph showing the results of hydrogen peroxide production by air aeration of the catalytic ceramic membrane prepared in Example 2, the unmodified ceramic membrane in Comparative Example 2, the iron-based ceramic membrane in Comparative Example 8, the manganese-iron-based ceramic membrane in Comparative Example 10, and the cerium-iron-based ceramic membrane in Comparative Example 12. As can be seen from the figure, when the air flow rate is 100 mL / min and the membrane flux is 40 L / m 2 Under the condition of aeration rate of 100 μg / h, the concentration of H₂O₂ generated by the catalytic ceramic membrane in Example 2 was maintained at approximately 30.5 μmol / L. Furthermore, no hydrogen peroxide was detected in the reaction systems of the unmodified ceramic membrane, the prepared iron-based ceramic membrane, the manganese-iron-based ceramic membrane, and the cerium-iron-based ceramic membrane, indicating that the unmodified ceramic membrane, the prepared iron-based ceramic membrane, the manganese-iron-based ceramic membrane, and the cerium-iron-based ceramic membrane were not capable of producing hydrogen peroxide through air aeration.

[0201] (6) FIG9 is a graph showing the results of the degradation of ofloxacin by the catalytic ceramic membrane described in Example 4 using air aeration at different air flow rates. As can be seen from the figure, as the air flow rate increases from 0, 100, 200, 300, 400 to 500 mL / min, the removal rate of ofloxacin by the catalytic ceramic membrane activated air increases from 29.0%, 45.1%, 48.3%, 52.5%, 56.7% to 62.9% (wherein when the air flow rate is 0, the catalytic ceramic membrane utilizes the dissolved oxygen in the ofloxacin aqueous solution to catalytically degrade ofloxacin; the dissolved oxygen amount is the saturated dissolved oxygen concentration of the ofloxacin aqueous solution at room temperature and pressure, which is approximately 8.0-8.1 mg / L).

[0202] (7) FIG10 shows the results of catalytic degradation of emerging pollutants in actual pharmaceutical wastewater using air aeration for the catalytic ceramic membrane prepared in Example 5 and the unmodified ceramic membrane prepared in Comparative Example 3. As can be seen from the figure, the total removal rates of emerging pollutants in actual pharmaceutical wastewater using activated air for the catalytic ceramic membrane and the unmodified ceramic membrane were 57.3% and 8.8%, respectively. These results demonstrate that the catalytic ceramic membrane prepared in accordance with the present invention is effective in removing various emerging pollutants in actual pharmaceutical wastewater using activated air.

[0203] (8) FIG11 shows the results of catalytic degradation of emerging pollutants in actual pharmaceutical wastewater using pure oxygen aeration using the catalytic ceramic membrane prepared in Example 6 and the unmodified ceramic membrane prepared in Comparative Example 4. As can be seen from the figure, the total removal rates of emerging pollutants in actual pharmaceutical wastewater using activated oxygen by the catalytic ceramic membrane and the unmodified ceramic membrane are 94.2% and 10.2%, respectively. These results demonstrate that the catalytic ceramic membrane prepared in the present invention is excellent in removing various emerging pollutants in actual pharmaceutical wastewater using activated oxygen.

[0204] (9) FIG12 is a graph showing the membrane flux variation of actual pharmaceutical wastewater filtered by the catalytic ceramic membrane prepared in Example 7 and the unmodified ceramic membrane in Comparative Example 5 using air aeration. As can be seen from the figure, the membrane permeability of the catalytic ceramic membrane increased from 10.3 L / m to 10.3 L / m under the cleaning conditions of 30 min membrane filtration and 10 min air cleaning for 5 filtration-cleaning cycles. 2 / h / bar dropped to 82.6L / m 2 / h / bar; the membrane permeability of the unmodified ceramic membrane is from 100.1L / m 2 / h / bar dropped to 44.9L / m 2 / h / bar. The results show that the catalytic ceramic membrane prepared by the present invention has good activated air self-cleaning function.

[0205] (10) FIG13 is a graph showing the membrane flux variation of actual pharmaceutical wastewater filtered by the catalytic ceramic membrane prepared in Example 8 and the unmodified ceramic membrane in Comparative Example 6 using pure oxygen aeration. As can be seen from the figure, the membrane permeation of the catalytic ceramic membrane remained almost unchanged after five filtration-cleaning cycles under the cleaning conditions of 30 minutes of membrane filtration and 10 minutes of pure oxygen cleaning; while the membrane permeation of the unmodified ceramic membrane increased from 99.5 L / m 2 / h / bar dropped to 46.8L / m 2 / h / bar. The results show that the catalytic ceramic membrane prepared by the present invention has excellent activated oxygen self-cleaning function.

[0206] As shown in Figures 10-11, the pollutants in the treatment of TCM wastewater in Examples 5-6 and Comparative Examples 3-4 are shown in Table 1:

[0207] Table 1 Pollutant information table for pharmaceutical wastewater treatment

[0208] In summary, the present invention provides a catalytic ceramic membrane that addresses the issues of low catalytic site utilization and difficulty in catalyst recovery. This multi-component catalytic membrane possesses strong oxygen activation capabilities, enabling the production of hydrogen peroxide from oxygen in water without energy input. This provides a potential alternative to traditional methods for hydrogen peroxide production, which are highly polluting, energy-intensive, and costly. It has applications in the efficient degradation of emerging pollutants in water and self-cleaning of separation membranes.

[0209] The combination of transition metal oxides and ceramic membranes has the characteristic of improving the utilization efficiency of catalytic sites. The present invention adopts multi-metal oxides such as manganese, iron and titanium to load into the ceramic membrane, and obtains a large number of effective active sites by inducing charge redistribution and adjusting the electronic structure, thereby solving the problems of single catalytic sites and poor redox ability, and enhancing the ability of the ceramic membrane to activate oxygen. When the catalytic ceramic membrane of the present invention is used to prepare hydrogen peroxide, due to the presence of rich catalytic sites such as zirconium, titanium, iron and manganese in the catalytic ceramic membrane, it has high oxygen affinity. These catalytic sites and O2 molecules are confined in the membrane pores, which can improve the mass transfer efficiency between O2 molecules and catalytic sites, accelerate the charge transfer in the catalytic system, and realize the production of hydrogen peroxide by utilizing oxygen in the air without the need for external energy (such as light or electricity) input.

[0210] The present invention is based on membrane-based nanotechnology, and the O2 molecules and the catalyst are locally confined in a nanoreactor (such as the pores of a catalytic ceramic membrane) for reaction. The reaction kinetics induced in the nanoreactor will be much faster than the reaction kinetics of the catalyst and O2 in the bulk suspension liquid, achieving efficient H2O2 production efficiency. In particular, the catalytic membrane catalyzes the production of H2O2 by O2 molecules, which can be applied to environmental water treatment to degrade organic pollutants, while also slowing down membrane pollution and achieving the in-situ self-cleaning function of the membrane. Therefore, in order to solve the problems of high energy consumption in conventional H2O2 production processes and the difficulty of recycling and reusing conventional powder catalysts during application, the present invention loads a high-efficiency catalyst (catalyst) into a nanoporous ceramic membrane to enhance the mass transfer of local O2 and promote the efficient generation of H2O2, thereby broadening its application in water treatment.

[0211] It should be noted that, unless otherwise specified, “room temperature” or “normal temperature” herein refers to approximately 25° C.; and “approximately” for numerical values ​​herein means an error of ±5%.

[0212] While the embodiments of the present invention have been described in detail above with reference to the accompanying drawings, the present invention is not limited to the embodiments described above. Various modifications may be made within the scope of knowledge possessed by a person skilled in the art without departing from the spirit of the present invention. Furthermore, the embodiments of the present invention and the features thereof may be combined with one another unless there is a conflict.

Claims

1. A catalytic ceramic membrane, It is characterized in that The invention comprises a ceramic base membrane and a catalyst supported on the ceramic membrane. The catalyst comprises metal elements Ti, Mn and Fe. The ceramic base membrane comprises at least one of the metal elements Zr, Ti or Al.

2. The catalytic ceramic membrane according to claim 1, It is characterized in that The ceramic-based membrane is a nanoporous ceramic membrane, and the catalyst is loaded on the surface of the ceramic-based membrane and / or loaded in the membrane pores of the ceramic-based membrane.

3. The catalytic ceramic membrane according to claim 1, It is characterized in that In the catalyst, the molar ratio of the elements Ti, Mn and Fe is (0.1-1):(1-3):(1-3); And / or, the catalyst comprises Ti, Mn 3 O 4 and Fe 3 O 4 .

4. A method for preparing a catalytic ceramic membrane, It is characterized in that The method comprises the following steps: using a ceramic-based membrane as a filter membrane, filtering a catalyst precursor liquid to obtain a filtrate and a ceramic-based membrane after filtration, and performing a hydrothermal reaction to obtain the catalytic ceramic membrane; Preferably, the preparation method comprises the following steps: S1: Using a ceramic-based membrane as a filter membrane, vacuum-filtering the catalyst precursor liquid to obtain a filtrate and a ceramic-based membrane after filtration; S2: placing the filtrate obtained in step S1 and the ceramic base membrane in a reaction container, subjecting the mixture to a hydrothermal reaction to obtain a catalytic ceramic membrane precursor, and calcining the precursor to obtain the catalytic ceramic membrane.

5. A ceramic membrane module, It is characterized in that Comprising the catalytic ceramic membrane described in any one of claims 1-3.

6. A reaction device, It is characterized in that It comprises a reactor, wherein the reactor is the ceramic membrane assembly as claimed in claim 5.

7. The catalytic ceramic membrane according to any one of claims 1 to 3, the ceramic membrane assembly according to claim 5, or the reaction device according to claim 6 in the preparation of H 2 O 2 , degradation of organic pollutants or application in water treatment.

8. Placing the catalytic ceramic membrane according to any one of claims 1 to 3 in a system containing water and oxygen to prepare H 2 O 2 application.

9. The use according to claim 8, It is characterized in that The H 2 O 2 The preparation comprises the following steps: mixing a reaction gas containing oxygen with a solution containing water, and obtaining H 2 O 2 ; Preferably, the reaction gas is oxygen or air.

10. A method for treating a water body containing pollutants, It is characterized in that The method comprises the following steps: placing a catalytic ceramic membrane in the water body; wherein the catalytic ceramic membrane is the catalytic ceramic membrane according to any one of claims 1 to 3; Preferably, the treatment method comprises the following steps: mixing the reaction gas containing oxygen with the water body, and removing pollutants in the water body through the action of the catalytic ceramic membrane; Preferably, the water body is pharmaceutical wastewater; preferably, the pollutants include at least one of ofloxacin, ciprofloxacin, tylosin, paracetamol, bezafibrate, bisphenol A, octylphenol, estradiol, estrone, ethinyl estradiol, salicylic acid, diclofenac, ibuprofen, indomethacin, theophylline, caffeine, sulfapyridine, atenolol, pirenzepine, metoprolol, sulfamethoxazole, erythromycin, tetracycline, trimethoprim-butyl pyridine, DEET, oxytetracycline, roxithromycin, crotamiton, clarithromycin, carbamazepine, azithromycin or ifenprodil.

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