A catalytic ceramic membrane and its preparation method and application

Abstract

The present invention discloses a catalytic ceramic membrane and a preparation method and application thereof. The catalytic ceramic membrane of the present invention comprises a ceramic base membrane and a catalyst loaded on the ceramic membrane, wherein the catalyst comprises metal elements Ti, Mn and Fe, and the ceramic base membrane comprises at least one of metal elements Zr, Ti or Al. The catalytic ceramic membrane of the present invention, when applied to the preparation of H2O2, has a high ability to be activated by oxygen in the air, and realizes the production of hydrogen peroxide by air aeration without the input of external energy (such as light or electricity), and the generation efficiency of H2O2 is high.

Description

Technical Field

[0001] The invention belongs to the technical field of hydrogen peroxide preparation, and specifically 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 industry, energy and environmental applications. Its traditional preparation method is usually produced by 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. The in-situ activation of O2 to produce H2O2 by electro- and photocatalytic technology has gradually replaced the anthraquinone process, but it still consumes a lot of electricity and light energy. At present, the method of heterogeneous catalysts is used to activate O2 by charge transfer to generate H2O2. However, at present, the production efficiency of H2O2 using conventional heterogeneous catalysts is low, which has affected the development of hydrogen peroxide preparation to a certain extent. Summary of the invention

[0003] The present invention aims to solve at least one of the technical problems existing in the above-mentioned prior art. To this end, the present invention proposes a catalytic ceramic membrane, which is applied to the preparation of H2O2, has a high activation ability, can better utilize oxygen in the air for activation, and realizes the production of hydrogen peroxide by air aeration without the input of external energy (such as light and electricity), and the production efficiency of H2O2 is high.

[0004] The invention also provides a method for preparing the catalytic ceramic membrane.

[0005] The invention also provides a ceramic membrane component.

[0006] The invention also provides a reaction device.

[0007] The present invention also proposes the application of the above-mentioned catalytic ceramic membrane, ceramic membrane assembly or reaction device.

[0008] The present invention also proposes that the catalytic ceramic membrane is used for the preparation of H2O2.

[0009] The invention also provides a method for treating water containing pollutants.

[0010] 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.

[0011] The catalytic ceramic membrane according to the embodiment of the present invention has at least the following beneficial effects:

[0012] The present invention uses multiple catalysts such as manganese, iron, and titanium to load 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.

[0013] The catalytic ceramic membrane of the present invention is applied to the preparation of H2O2. Since the catalytic ceramic membrane containing zirconium, titanium, manganese and iron of the present invention has high oxygen affinity, especially can be activated by oxygen in the air, the catalytic sites in the membrane pores are evenly distributed, and the mass transfer efficiency between oxygen and catalytic sites in the membrane pores can be enhanced, so that H2O2 can be produced by oxygen or even air aeration without the input of external energy (such as light and electricity), and the production efficiency of H2O2 is high. The catalytic ceramic membrane can also activate the produced hydrogen peroxide to generate active species, degrade organic pollutants in water, purify water quality and alleviate membrane pollution.

[0014] In addition, the catalytic ceramic membrane of the present invention is a ceramic-based membrane (such as a zirconium-titanium-based ceramic membrane) that contains catalysts such as titanium, iron, and manganese, which is easy to recycle. In some embodiments of the present invention, the ceramic-based membrane is a nanoporous ceramic membrane, and the catalyst is loaded on the surface of the ceramic-based membrane and / or in the membrane pores of the ceramic-based membrane.

[0015] The present invention is based on membrane-based nanotechnology, and the O2 molecules and catalysts can be locally confined in a nanoreactor (such as catalytic ceramic membrane pores, membrane surface) 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 ceramic membrane catalyzes O2 molecules to produce H2O2, which can be used for environmental water treatment and degradation of 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 the conventional H2O2 production process and the difficulty of recycling and reusing conventional powder catalysts during application, the present invention loads a high-efficiency catalyst in 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.

[0016] In some embodiments of the present invention, the catalytically active components in the catalytic ceramic membrane include the elements zirconium, titanium, iron and manganese.

[0017] The present invention proposes to use a catalytic ceramic membrane containing zirconium, titanium, manganese and iron with high oxygen affinity, wherein the combination of a catalyst containing a transition metal element and a ceramic-based 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.

[0018] 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.

[0019] 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, and the raw materials are widely available, with low preparation cost and low cost for producing hydrogen peroxide.

[0020] In the present invention, the catalyst is loaded into a ceramic-based membrane (such as a zirconium-titanium-based ceramic membrane and an aluminum-based ceramic membrane), and its active components also include metal elements contained in the ceramic-based membrane (such as Zr, Ti and Al elements). Processes such as multi-metal electron transfer occur between the catalyst, and a large number of effective active sites are obtained by inducing charge redistribution and adjusting the electronic structure, thereby solving the problems of single catalytic site and poor redox ability, and enhancing the ability of the catalytic ceramic membrane to activate oxygen.

[0021] In some embodiments of the present invention, in the catalyst, the molar ratio of the elements Ti, Mn and Fe is (0.1-1):(1-3):(1-3).

[0022] In some embodiments of the present invention, the catalyst comprises Ti, Mn3O4 and Fe3O4.

[0023] 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).

[0024] In some embodiments of the present invention, oxygen vacancy structures are distributed in the catalyst.

[0025] 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.

[0026] 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.

[0027] In some embodiments of the present invention, the components of the ceramic-based membrane include ZrO2 and TiO2.

[0028] In some embodiments of the present invention, the thickness of the ceramic-based membrane is 1.5-5 mm, and can be 2.5 mm.

[0029] 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.

[0030] The second aspect of the present invention proposes a method for preparing a catalytic ceramic membrane, comprising 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 obtaining the catalytic ceramic membrane through a hydrothermal reaction.

[0031] In some embodiments of the present invention, the preparation method comprises the following steps:

[0032] S1, using a ceramic-based membrane as a filter membrane, vacuum-filtering a catalyst precursor liquid to obtain a filtrate and a ceramic-based membrane after filtration;

[0033] 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.

[0034] 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.

[0035] In some embodiments of the present invention, in step S1, the vacuum degree of vacuum filtration is 0.05-0.15 MPa.

[0036] In some embodiments of the present invention, in step S1, the vacuum degree of vacuum filtration is 0.01-0.08 MPa.

[0037] In some embodiments of the present invention, in step S1, the vacuum degree of vacuum filtration is 0.02-0.1 MPa.

[0038] 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.

[0039] 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 h.

[0040] In some embodiments of the present invention, in step S2, the catalytic ceramic membrane precursor is dried and then calcined.

[0041] 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.

[0042] In some embodiments of the present invention, the calcination temperature is 200-1000°C, and can be 300-1000°C.

[0043] In some embodiments of the present invention, the calcination time is 2-10 hours, and can be 2-6 hours.

[0044] 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 for continuous 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.

[0045] 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 a precursor liquid of the catalyst under alkaline conditions.

[0046] In some embodiments of the present invention, the titanium source includes at least one of a titanium salt or tetrabutyl titanate.

[0047] In some embodiments of the present invention, the titanium salt comprises titanium sulfate.

[0048] In some embodiments of the invention, the manganese source comprises a manganese salt.

[0049] In some embodiments of the present invention, the manganese salt comprises at least one of manganese nitrate or potassium permanganate.

[0050] In some embodiments of the invention, the iron source comprises an iron salt.

[0051] In some embodiments of the present invention, the iron salt includes at least one of ferric nitrate, ferric sulfate and hydrates thereof.

[0052] 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).

[0053] In some embodiments of the present invention, the precursor liquid of the catalyst is prepared, specifically comprising 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 precursor liquid of the catalyst.

[0054] In some embodiments of the present invention, preparing the precursor liquid of the catalyst specifically comprises the following operations:

[0055] S0-1, mixing a titanium source, a manganese source, an iron source and water to obtain the first solution;

[0056] mixing an alkaline substance with water to obtain the second solution;

[0057] S0-2, mixing the first solution and the second solution, stirring, to obtain a precursor solution of the catalyst.

[0058] 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.

[0059] 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%.

[0060] In some embodiments of the present invention, in step S0-1, the first solution also includes a coprecipitant.

[0061] In some embodiments of the present invention, the coprecipitating agent comprises at least one of polyvinyl pyrrolidone or polyethylene glycol.

[0062] In some embodiments of the present invention, in step S0-2, the stirring time is 1-6 hours.

[0063] The preparation method of the catalytic ceramic membrane of the present invention has a wide source of raw materials, low cost, no need for complex operation control in the production process, mild reaction conditions, no need for expensive equipment, and is conducive to realizing industrial large-scale production.

[0064] The third aspect of the present invention provides a ceramic membrane assembly, comprising the above-mentioned catalytic ceramic membrane.

[0065] In some embodiments of the present invention, the ceramic membrane assembly further includes a shell and a reaction chamber formed in the shell, and the catalytic ceramic membrane is located in the reaction chamber.

[0066] In some embodiments of the present invention, the ceramic membrane assembly includes an air inlet pipeline, a liquid inlet pipeline, and a material outlet pipeline, all of which are connected to the reaction chamber.

[0067] 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.

[0068] 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.

[0069] 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.

[0070] 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.

[0071] Optionally, when the housing includes a top cover, a connecting wall and a bottom cover, the liquid inlet pipeline and the air inlet pipeline can be connected to the connecting wall or the bottom cover, and the discharge pipeline can 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.

[0072] 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.

[0073] In some embodiments of the present invention, a flow meter is provided on the air intake pipeline.

[0074] In some embodiments of the present invention, a pressure gauge is installed on the discharge pipeline.

[0075] In some embodiments of the present invention, the reactor further comprises a liquid inlet reservoir and a material outlet reservoir, the liquid inlet reservoir is communicated with the liquid inlet pipeline, and the material outlet reservoir is communicated with the material outlet pipeline.

[0076] 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.

[0077] 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.

[0078] The catalytic ceramic membrane of the present invention has a high ability to be activated by oxygen in the air, and the catalytic sites in the membrane pores are evenly distributed, which can enhance the mass transfer efficiency between the oxygen in the membrane pores and the catalytic sites, and realize the production of hydrogen peroxide by air aeration without the input of external energy (such as light or electricity). The catalytic ceramic membrane can also activate the produced hydrogen peroxide to generate active species, degrade organic pollutants in water, purify water quality and alleviate membrane pollution. In addition, since the catalyst in the catalytic ceramic membrane of the present invention is fixed on the surface of the ceramic base membrane, the problem of the difficulty in recycling the catalyst is solved, and an environmentally friendly method for preparing hydrogen peroxide is provided.

[0079] The sixth aspect of the present invention proposes placing the above-mentioned catalytic ceramic membrane in a system containing water and oxygen to prepare H2O2.

[0080] 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 above-mentioned catalytic ceramic membrane.

[0081] The preparation of H2O2 according to the embodiment of the present invention has at least the following beneficial effects:

[0082] The catalytic ceramic membrane of the present invention has high oxygen affinity and a high ability to be activated by oxygen in the air. The catalytic sites in the membrane pores are evenly distributed, 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 by using oxygen or even air aeration without the need for external energy (such as light or electricity) input.

[0083] In some embodiments of the present invention, the concentration of hydrogen peroxide in the effluent of the H2O2 production equipment is monitored to determine and calculate the production efficiency of hydrogen peroxide.

[0084] In some embodiments of the present invention, the reaction gas is oxygen or air, preferably air.

[0085] In some embodiments of the present invention, the aqueous solution is water.

[0086] 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.

[0087] In some embodiments of the present invention, the treatment method comprises 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.

[0088] The water treatment method according to the embodiment of the present invention has at least the following beneficial effects:

[0089] When the catalytic ceramic membrane of the present invention is used for treating water bodies containing pollutants, since 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.

[0090] 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.

[0091] In some embodiments of the present invention, the reaction gas is oxygen or air, preferably air.

[0092] 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.

[0093] In some embodiments of the present invention, the water body is wastewater, which can be medical wastewater.

[0094] 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 strongly 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.

[0095] 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.

[0096] 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.

[0097] In some embodiments of the present invention, when not treated by the treatment method, the total concentration of pollutants in the wastewater is 300-1000 μg / L.

[0098] 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.

[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 5-150 μg / L.

[0100] 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-butyl pyridine, DEET, oxytetracycline, roxithromycin, crotamiton, clarithromycin, carbamazepine, azithromycin or ifenprodil.

[0101] In some embodiments of the present invention, the treatment method further comprises the step of cleaning the catalytic ceramic membrane.

[0102] 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.

[0103] In some embodiments of the present invention, the processing method comprises the following steps:

[0104] Sa-1, pumping wastewater into the membrane module, exposing it to air or oxygen, and treating pollutants in the wastewater through the action of the catalytic ceramic membrane for a treatment time of t1;

[0105] Sa-2, water is used instead of medical wastewater to be pumped into the membrane assembly, and air or oxygen is exposed to it. H2O2 is generated through the action of the catalytic ceramic membrane to clean the catalytic ceramic membrane. The cleaning time is t2.

[0106] In some embodiments of the present invention, t1 is 20-40 min, and / or t2 is 5-15 min.

[0107] 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.

[0108] 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.

[0109] Through the above implementation, the self-cleaning effect of the catalytic ceramic membrane is judged by monitoring the change of the membrane flux of the catalytic ceramic membrane during the membrane filtration process. Specifically, in the process of filtering actual 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 hydrogen peroxide to produce strongly oxidizing free radicals and non-free radical species, which have the function of degrading organic pollutants trapped on the membrane surface when filtering pharmaceutical wastewater, as well as various emerging pollutants in pharmaceutical wastewater, so that the membrane flux remains constant and the self-cleaning function is achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0110] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein:

[0111] Figure 1 This is a surface scanning electron microscope image of the catalytic ceramic membrane in Example 1 of the present invention;

[0112] Figure 2 This is a scanning electron microscope image of a cross section of the catalytic ceramic membrane in Example 1 of the present invention;

[0113] Figure 3 This is a photo of the catalytic ceramic membrane in Example 1 of the present invention;

[0114] Figure 4 This is a schematic diagram of the structure of the reaction device in Example 2 of the present invention;

[0115] Figure 5 This is a test result diagram of hydrogen peroxide production at different membrane fluxes in Example 2 of the present invention;

[0116] Figure 6 This is a test result diagram of hydrogen peroxide generation at different air flow rates in Example 3 of the present invention;

[0117] Figure 7 The test result diagram of H2O2 produced by the system under different catalyst amounts in Comparative Example 1;

[0118] Figure 8 This is a test result diagram of hydrogen peroxide generation by air aeration in Example 2, Comparative Example 2, Comparative Example 8, Comparative Example 10 and Comparative Example 12 of the present invention;

[0119] Fig. 9 This is a test result diagram of the degradation of ofloxacin in wastewater at different air flow rates in Example 4 of the present invention;

[0120] Fig.10 This is a test result diagram of catalytic degradation of emerging pollutants in pharmaceutical wastewater using air aeration in Example 5 of the present invention and Comparative Example 3;

[0121] Fig.11 This is a test result diagram of catalytic degradation of emerging pollutants in pharmaceutical wastewater using pure oxygen aeration in Example 6 of the present invention and Comparative Example 4;

[0122] Fig.12 This is a graph showing the change in membrane flux of medical wastewater filtered by air aeration in Example 7 of the present invention and Comparative Example 5;

[0123] Fig.13 This is a graph showing the membrane flux change results of filtering medical wastewater using pure oxygen aeration in Example 8 of the present invention and Comparative Example 6. DETAILED DESCRIPTION

[0124] The following will be combined with the embodiments to clearly and completely describe the concept of the present invention and the technical effects produced, so as to fully understand the purpose, characteristics and effects of the present invention. Obviously, the described embodiments 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.

[0125] The experimental methods in the following examples without specifying specific conditions are generally carried out according to conventional conditions in the art or conditions recommended by the manufacturers; the raw materials and reagents used, unless otherwise specified, are all raw materials and reagents that can be obtained from commercial channels such as conventional markets.

[0126] 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;

[0127] Example 1

[0128] This embodiment discloses a catalytic ceramic membrane with a thickness of about 2.5 mm, including a ceramic base membrane and a catalyst loaded 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 about 1:999, and the particle size of the catalyst particles is about 10-50 nm. The preparation reaction process of the catalytic ceramic membrane includes the following steps:

[0129] (I) Weigh appropriate amounts of 50% manganese nitrate solution, ferrous sulfate heptahydrate, and titanium sulfate and dissolve them in 30 mL of pure water to form a first solution, and weigh 200 mg of sodium hydroxide and dissolve them in 10 mL of pure water to form a second solution. The molar ratio of the element titanium in the titanium sulfate, the element manganese in the manganese nitrate, and the element iron in the ferric sulfate is 0.5:1:1.

[0130] (II) The first solution and the second solution were stirred at room temperature for 1 hour to form a mixed suspension liquid.

[0131] (III) The zirconium-titanium ceramic membrane is used as a filter membrane. The mixed suspension liquid is vacuum filtered in the zirconium-titanium ceramic membrane at a filtration pressure of 0.08 MPa.

[0132] (IV) The ceramic membrane obtained after the above filtration and the filtrate after filtration were then transferred to a polytetrafluoroethylene liner, which was then sealed in a reactor and mixed and hydrothermally heated in an oven at 100° C. for 24 h.

[0133] (V) After the reaction is completed and 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.

[0134] This embodiment also discloses a ceramic membrane assembly, including the catalytic ceramic membrane prepared in this embodiment, a shell and a reaction chamber formed in the shell, the catalytic ceramic membrane is located in the reaction chamber, and the ceramic membrane assembly is provided with an air inlet pipeline, a liquid inlet pipeline and a discharge pipeline connected to the reaction chamber. Among them, 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, and the liquid inlet pipeline and the discharge pipeline are arranged on both sides of the catalytic ceramic membrane respectively, the liquid inlet pipeline and the air inlet pipeline are located on the same side of the catalytic ceramic membrane, and the catalytic ceramic membrane is located above the liquid inlet pipeline. The catalytic ceramic membrane is fixed in the membrane assembly.

[0135] 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.

[0136] This embodiment also discloses a reaction device, and its structural schematic diagram is as follows: Figure 4 As shown, it includes 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 through the liquid inlet pipeline by a peristaltic pump. The material in the reactor can be optionally transported to the discharge reservoir through 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).

[0137] Example 2

[0138] This embodiment discloses a method for preparing hydrogen peroxide, which uses the reaction device and / or ceramic membrane assembly in Example 1 and air aeration to produce hydrogen peroxide at different membrane fluxes, including the following steps:

[0139] 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 water is measured.

[0140] Example 3

[0141] This embodiment discloses a method for preparing hydrogen peroxide, which uses the reaction device and / or ceramic membrane assembly in Example 1 and air aeration at different air flow rates to produce hydrogen peroxide, including the following steps:

[0142] 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 water is measured.

[0143] Example 4

[0144] This embodiment discloses a wastewater treatment method, which uses the reaction device and / or ceramic membrane assembly in Example 1 to perform an experiment of degrading the emerging pollutant ofloxacin by air aeration at different air flow rates, comprising the following steps:

[0145] 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.

[0146] Example 5

[0147] This embodiment discloses a wastewater treatment method, which uses the reaction device and / or ceramic membrane assembly in Example 1 and air aeration to catalytically remove various emerging pollutants in pharmaceutical wastewater, including the following steps:

[0148] The pharmaceutical wastewater was pumped into the ceramic membrane module, and air was exposed to it at a flow rate of 150 mL / min, and the water flux was adjusted to 40 L / m 2 / h, catalytically degrade emerging pollutants in pharmaceutical wastewater in the reaction system, and measure the concentration changes of various emerging pollutants during membrane filtration.

[0149] Example 6

[0150] This embodiment discloses a wastewater treatment method, which uses the reaction device and / or ceramic membrane assembly in Example 1 and pure oxygen aeration to catalytically remove various emerging pollutants in pharmaceutical wastewater, including the following steps:

[0151] The pharmaceutical wastewater was pumped into the ceramic membrane module, and oxygen was introduced into it at a flow rate of 150 mL / min, and the water flux was adjusted to 40 L / m 2 / h, catalytically degrade emerging pollutants in pharmaceutical wastewater in the reaction system, and measure the concentration changes of various emerging pollutants during membrane filtration.

[0152] Example 7

[0153] This embodiment discloses a wastewater treatment method, which uses the reaction device and / or ceramic membrane assembly in Example 1 and air aeration to perform catalytic filtration of various emerging pollutants in pharmaceutical wastewater, including the following steps:

[0154] The pharmaceutical wastewater was pumped into the ceramic membrane module, and air was exposed to it at a flow rate of 150 mL / min, and the water flux was adjusted to 40 L / m 2 / h, catalytically filtering pharmaceutical wastewater in the reaction system. Including:

[0155] 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;

[0156] Cleaning step: After the pollutant treatment step, deionized water was used to replace the medical wastewater. The water inlet pump pumped deionized water into the membrane module and exposed it to air for 10 minutes, that is, the cleaning time was 10 minutes. The pollutant treatment step-cleaning step (30 minutes of filtration-10 minutes of cleaning condition) was cycled for 5 times, and the change of membrane flux during the membrane filtration process was measured.

[0157] Example 8

[0158] This embodiment discloses a wastewater treatment method, which uses the reaction device and / or ceramic membrane assembly in Example 1 and pure oxygen aeration to conduct catalytic filtration experiments on various emerging pollutants in medical wastewater. The difference between this embodiment and Example 7 is that oxygen is used in this embodiment instead of the air in Example 7, the gas aeration flow rate is 150 mL / min, and other conditions are the same as Example 7.

[0159] Comparative Example 1

[0160] 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:

[0161] Pour 100mL of deionized water into a beaker, add an appropriate amount of ternary catalyst 0.5Ti-Mn3O4 / Fe3O4 (catalyst addition amount: 200mg / L, 400mg / L, 600mg / L, 800mg / L, 1000mg / L) into the beaker, and expose air at a flow rate of 100mL / min to generate hydrogen peroxide in the reaction system. Measure the production of hydrogen peroxide in water at a certain time.

[0162] Comparative Example 2

[0163] This comparative example discloses a method for preparing hydrogen peroxide, which differs from Example 2 in 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, and the zirconium-titanium-manganese-iron catalytic ceramic membrane in Example 2 is replaced by a zirconium-titanium-manganese-iron catalytic 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.

[0164] Comparative Example 3

[0165] This comparative example discloses a wastewater treatment method, which differs from Example 5 in that: the ceramic membrane in the reaction device and / or ceramic membrane assembly used in this comparative example is different from that in Example 5, and the zirconium-titanium-manganese-iron catalytic ceramic membrane in Example 5 is replaced by a zirconium-titanium-manganese-iron catalytic ceramic membrane in this comparative example. The rest is the same as Example 5.

[0166] Comparative Example 4

[0167] This comparative example discloses a wastewater treatment method, which differs from Example 6 in that: the ceramic membrane in the reaction device and / or ceramic membrane assembly used in this comparative example is different from that in Example 6, and the zirconium-titanium-manganese-iron catalytic ceramic membrane in Example 6 is replaced by a zirconium-titanium-manganese-iron catalytic ceramic membrane in this comparative example. The rest is the same as Example 6.

[0168] Comparative Example 5

[0169] This comparative example discloses a wastewater treatment method, which differs from Example 7 in that: the ceramic membrane in the reaction device and / or ceramic membrane assembly used in this comparative example is different from that in Example 7, and the zirconium-titanium-manganese-iron catalytic ceramic membrane in Example 7 is replaced by a zirconium-titanium-manganese-iron catalytic ceramic membrane in this comparative example. The rest is the same as Example 7.

[0170] Comparative Example 6

[0171] This comparative example discloses a wastewater treatment method, which differs from Example 8 in that: the ceramic membrane in the reaction device and / or ceramic membrane assembly used in this comparative example is different from that in Example 8, and the zirconium-titanium-manganese-iron catalytic ceramic membrane in Example 8 is replaced by a zirconium-titanium-manganese-iron catalytic ceramic membrane in this comparative example. The rest is the same as Example 8.

[0172] Comparative Example 7

[0173] This comparative example discloses an iron-based ceramic membrane, which is different from Example 1 in that: Step (I) in this comparative example is: 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 in Example 1.

[0174] This comparative example also discloses a ceramic membrane assembly, which is different from Example 1 in that an iron-based ceramic membrane is used to replace the catalytic ceramic membrane in Example 1 in this comparative example.

[0175] 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.

[0176] Comparative Example 8

[0177] This comparative example discloses a method for preparing hydrogen peroxide, which differs from Example 2 in 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 40L / m 2 / h, and the rest is the same as in Example 2.

[0178] Comparative Example 9

[0179] This comparative example discloses a manganese-iron-based ceramic membrane, which is different from Example 1 in that: Step (I) in this comparative example is: weighing an appropriate amount of 50% manganese nitrate solution and ferrous 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 ferrous sulfate is 1:1. The remaining steps are the same as in Example 1.

[0180] This comparative example also discloses a ceramic membrane assembly, which is different 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.

[0181] 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.

[0182] Comparative Example 10

[0183] This comparative example discloses a method for preparing hydrogen peroxide, which differs from Example 2 in 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 manganese-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 40L / m 2 / h, and the rest is the same as in Example 2.

[0184] Comparative Example 11

[0185] This comparative example discloses a ferrocerium-based ceramic membrane, which is different from Example 1 in that: Step (I) in this comparative example is: 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.

[0186] This comparative example also discloses a ceramic membrane assembly, which is different 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.

[0187] 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.

[0188] Comparative Example 12

[0189] This comparative example discloses a method for preparing hydrogen peroxide, which differs from Example 2 in 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.

[0190] Test example

[0191] This test example tests the catalyst ceramic membrane obtained in the examples and comparative examples, the results of preparing hydrogen peroxide, and the results of wastewater treatment. Specifically, it includes:

[0192] (1) Microstructure test of the zirconium-titanium-manganese-iron catalytic ceramic membrane prepared in Example 1:

[0193] The scanning electron microscope image of the catalytic ceramic membrane surface is as follows: Figure 1 As shown by Figure 1 It can be seen that the surface of the catalytic ceramic membrane prepared by the present invention is relatively uniform and flat, dense and porous.

[0194] The scanning electron microscope image of the cross section of the catalytic ceramic membrane is as follows: Figure 2 As shown by Figure 2 It can be seen that the catalytic ceramic membrane prepared by the present invention includes a dense film 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 film layer is composed of smaller particles, the support layer particles are larger, and the thickness of the dense film layer is about 10μm.

[0195] (2) Figure 5 The results of the catalytic ceramic membrane described in Example 2 producing hydrogen peroxide using air aeration at different membrane fluxes are shown in the figure. 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.

[0196] (3) Figure 6The result diagram of the catalytic ceramic membrane in Example 3 using air aeration to produce hydrogen peroxide at different air flow rates. It can be seen from the figure that 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 of 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 the ionized water at normal temperature and pressure, which is about 8.0-8.1 mg / L).

[0197] (4) Figure 7 This is a test result chart of H2O2 produced by each system under different catalyst amounts in Example 1. By comparing with the test results of Examples 2-3 of the present invention, it can be seen that compared with only using a three-way catalyst for catalytic production of H2O2, the efficiency of using a catalytic ceramic membrane for catalytic production of H2O2 in the present invention is significantly higher and the catalytic effect is better.

[0198] (5) Figure 8 The results 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 using air aeration to produce hydrogen peroxide. It can be seen from the figure that when the air flow rate is 100 mL / min and the membrane flux is 40 L / m 2 / h, the concentration of H2O2 generated by activating air with the catalytic ceramic membrane in Example 2 was maintained at about 30.5 μmol / L. In addition, hydrogen peroxide was not 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 did not have the ability to produce hydrogen peroxide by air aeration.

[0199] (6) Fig. 9 The figure is a result diagram of the degradation of ofloxacin by air aeration at different air flow rates using the catalytic ceramic membrane described in Example 4. It can be seen from the figure that as the air flow rate increases from 0, 100, 200, 300, 400 to 500 mL / min, the removal rate of ofloxacin by activated air of the catalytic ceramic membrane 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 content is the saturated dissolved oxygen concentration of the ofloxacin aqueous solution at room temperature and pressure, which is about 8.0-8.1 mg / L).

[0200] (7) Fig.10 The results of the catalytic ceramic membrane prepared in Example 5 and the unmodified ceramic membrane in Comparative Example 3 using air aeration to catalytically degrade emerging pollutants in actual pharmaceutical wastewater. As can be seen from the figure, the total removal rates of emerging pollutants in actual pharmaceutical wastewater by activated air of the catalytic ceramic membrane and the unmodified ceramic membrane are 57.3% and 8.8%, respectively. The results show that the catalytic ceramic membrane prepared in the present invention has a good effect of removing various emerging pollutants in actual pharmaceutical wastewater by activated air.

[0201] (8) Fig.11 The results of the catalytic ceramic membrane prepared in Example 6 and the unmodified ceramic membrane in Comparative Example 4 using pure oxygen aeration to catalytically degrade emerging pollutants in actual pharmaceutical wastewater. As can be seen from the figure, the total removal rates of emerging pollutants in actual pharmaceutical wastewater by activated oxygen of the catalytic ceramic membrane and the unmodified ceramic membrane are 94.2% and 10.2%, respectively. The results show that the catalytic ceramic membrane prepared in the present invention has excellent effects of activated oxygen to remove various emerging pollutants in actual pharmaceutical wastewater.

[0202] (9) Fig.12 The catalytic ceramic membrane prepared in Example 7 and the unmodified ceramic membrane in Comparative Example 5 are respectively subjected to air aeration to filter actual pharmaceutical wastewater. As can be seen from the figure, under the cleaning conditions of 30 minutes of membrane filtration and 10 minutes of air washing, the membrane permeability of the catalytic ceramic membrane only increased from 100.3L / m 2 / h / bar drops to 82.6L / m 2 / h / bar; the membrane permeability of the unmodified ceramic membrane is 100.1L / m 2 / h / bar drops 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.

[0203] (10) Fig.13 The following is a graph showing the membrane flux change results of the catalytic ceramic membrane prepared in Example 8 and the unmodified ceramic membrane in Comparative Example 6 respectively using pure oxygen aeration to filter actual pharmaceutical wastewater. As can be seen from the figure, the membrane permeability of the catalytic ceramic membrane remained almost unchanged under the cleaning conditions of 30 minutes of membrane filtration and 10 minutes of pure oxygen cleaning, while the membrane permeability of the unmodified ceramic membrane increased from 99.5L / m 2 / h / bar drops 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.

[0204] like Figure 10-11 As shown, the pollutants in the treatment of traditional Chinese medicine wastewater in Examples 5-6 and Comparative Examples 3-4 are shown in Table 1:

[0205] Table 1 Pollutant information table of pharmaceutical wastewater treatment

[0206]

[0207] In summary, the present invention provides a catalytic ceramic membrane, which solves the problem of low utilization of catalytic sites and difficulty in recycling catalysts. The multi-component catalytic membrane has a strong oxygen activation ability and can use oxygen in water to prepare hydrogen peroxide without energy input, providing a potential alternative method for the traditional high-pollution, high-energy consumption, and high-cost hydrogen peroxide preparation, and is applied to the efficient degradation of emerging pollutants in water and the self-cleaning of separation membranes.

[0208] The combination of transition metal oxides and ceramic membranes has the characteristic of improving the utilization efficiency of catalytic sites. The present invention uses 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 abundant 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 using oxygen in the air without the input of external energy (such as light and electricity).

[0209] The present invention is based on membrane-based nanotechnology, and locally confines O2 molecules and catalysts in a nanoreactor (such as catalytic ceramic membrane pores) 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 O2 molecules to produce H2O2, which can be used in 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 the conventional H2O2 production process and the difficulty of recycling and reusing conventional powder catalysts during application, the present invention loads a high-efficiency catalyst (catalyst) in 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.

[0210] It should be noted that the “room temperature” or “normal temperature” in this article, unless otherwise specified, is approximately 25°C; the “approximately” for numerical values ​​in this article means an error of ±5%.

[0211] The embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments. Various changes can be made within the knowledge of ordinary technicians in the relevant technical field without departing from the purpose of the present invention. In addition, the embodiments of the present invention and the features in the embodiments can be combined with each other without 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, wherein the components of the ceramic base membrane include ZrO 2 and TiO 2 The mass ratio of the catalyst to the ceramic base membrane is 1: (700-1200); the catalyst includes Ti, Mn 3 O 4 and Fe 3 O 4 In the catalyst, the molar ratio of elements Ti, Mn and Fe is (0.1-1):(1-3):(1-3).

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. A method for preparing the catalytic ceramic membrane according to claim 1, It is characterized in that The method comprises the following steps: using a ceramic base membrane as a filter membrane, filtering a catalyst precursor liquid to obtain a filtrate and a filtered ceramic base membrane, and performing a hydrothermal reaction to obtain the catalytic ceramic membrane.

4. The method for preparing a catalytic ceramic membrane according to claim 3, It is characterized in that The preparation method comprises the following steps: S1, using a ceramic-based membrane as a filter membrane, vacuum-filtering a 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 It comprises the catalytic ceramic membrane as described in any one of claims 1-2.

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 2, the ceramic membrane assembly according to claim 5, or the reaction device according to claim 6 in the preparation of H 2 O 2 Application in.

8. The use according to claim 7, It is characterized in that The catalytic ceramic membrane was placed in a system containing water and oxygen to prepare H 2 O 2 .

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 .

10. The use according to claim 9, It is characterized in that The reaction gas is oxygen or air.

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