Ceramic membrane catalyst, preparation method of ceramic membrane catalyst, ceramic membrane catalytic reactor and application of ceramic membrane catalytic reactor

Abstract

The invention relates to the technical field of wastewater treatment, and discloses a ceramic membrane catalyst and a preparation method thereof as well as a ceramic membrane catalytic reactor and application thereof, the ceramic membrane catalyst comprises a ceramic membrane and bismuth oxide loaded on the ceramic membrane, and the loading capacity of the bismuth oxide is 1-100g / m < 2 >. By adopting the loaded ceramic membrane catalyst, the dissolution of ozone can be enhanced, the utilization rate of ozone is improved, the operation cost of an ozone process is reduced, and the treatment effect of the ozone process is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of wastewater treatment, and particularly relates to a ceramic membrane catalyst, a preparation method thereof, a ceramic membrane catalytic reactor and an application thereof. Background Art

[0002] Acrylic acid is the main raw material for synthesizing acrylate. Acrylic acid and its esters are widely used in industries such as coatings, adhesives, plastics, textiles, papermaking, rubber, petroleum, water treatment, chemical fibers, leather making, etc. The annual production capacity of the acrylic acid industry is as high as millions of tons, and the corresponding wastewater discharge is large. The acrylic acid wastewater has complex components, high concentration, strong acidity, certain corrosiveness, and contains various organic substances such as organic acids, esters, benzene, aldehydes, etc., most of which are toxic and harmful organic substances. In particular, the high content of acrylic acid in the wastewater is highly toxic, and it is difficult to treat by conventional biological methods.

[0003] Currently, for refractory organic wastewater such as acrylic acid wastewater, advanced oxidation methods are often used for treatment, including Fenton oxidation, electro-oxidation, ozone oxidation, etc. Among them, ozone oxidation has been widely concerned because of its stable process, no by-products, and low operating cost.

[0004] CN111530506A discloses an ozone catalytic oxidation ceramic membrane catalyst, a preparation method thereof, a ceramic membrane catalytic reactor and a wastewater treatment process, including a plurality of channels formed by ceramic membranes. The channels include adjacent wastewater channels and ozone channels. The wastewater channel has a wastewater inlet and a wastewater outlet, and the ozone gas channel has an ozone inlet; the pore size of the ceramic membrane is 0.01-10 μm; a catalyst is loaded on the ceramic membrane; the catalyst is metal and / or metal oxide. In this invention, ozone gas enters the wastewater through the ceramic membrane wall between gas and liquid. The ceramic membrane wall has a developed microporous structure. When the ozone gas passes through the ceramic membrane wall, it is dispersed into tiny bubbles and enters the wastewater system to be treated in the adjacent channel, playing a role in micro-porous dispersion of ozone, which can greatly improve the solubility of ozone in the wastewater to be treated and improve the utilization rate of ozone. This invention also provides a preparation method of an ozone catalytic oxidation ceramic membrane catalyst, a ceramic membrane catalytic reactor and a wastewater treatment process.

[0005] CN107915309B discloses a method for efficient separation and automatic recycling of powder catalyst during wastewater treatment by catalytic oxidation. The method includes four steps: influent mixing, catalytic oxidation reaction, catalyst separation and automatic recycling, clean water storage and pulse backwashing. Among them, the catalytic oxidation reaction uses a powder catalyst with a particle size range of 18 - 200 mesh. This method realizes the efficient separation of the powder catalyst by using a centrifugal hydraulic interception pulse separator. By coupling the tangential scouring of the filter cartridge surface inside the centrifugal hydraulic interception pulse separator by pressure water flow, the centrifugal force generated by the rotation of the filter cartridge, and pulse backwashing, the pressure difference caused by the accumulation of the powder catalyst on the filter cartridge surface is greatly reduced, thus ensuring the long-term, stable and efficient separation operation of the centrifugal hydraulic interception pulse separator. By using the ultraviolet lamp installed inside the centrifugal hydraulic interception pulse separator, the effect of photocatalytic oxidation for degrading organic pollutants is further enhanced.

[0006] In addition, in the prior art, either a diffuser is used for ozone distribution, resulting in easy collision and aggregation of the generated bubbles, low ozone utilization rate, ozone waste, and increased operating costs; or multiple dynamic devices are used, increasing the operating costs; or a static diaphragm is used, causing fouling of the ceramic diaphragm.

[0007] Therefore, it is of great significance to research and develop a wastewater treatment method. Summary of the Invention

[0008] The object of the present invention is to overcome the problems of low ozone utilization rate and fouling of ceramic membranes existing in the prior art, and provide a ceramic membrane catalyst and its preparation method, a ceramic membrane catalytic reactor and its application. By using the loaded ceramic membrane catalyst, the dissolution of ozone can be enhanced, the ozone utilization rate can be improved, the operating cost of the ozone process can be reduced, and the treatment effect of the ozone process can be improved.

[0009] To achieve the above object, in the first aspect of the present invention, a ceramic membrane catalyst is provided, wherein the ceramic membrane catalyst includes a ceramic membrane sheet and bismuth oxide loaded on the ceramic membrane sheet, and the loading amount of the bismuth oxide is 1 - 100 g / m 2 .

[0010] In the second aspect of the present invention, a preparation method of a ceramic membrane catalyst is provided, wherein the preparation method includes:

[0011] (1) Contacting bismuth nitrate, a structure-directing agent and dilute nitric acid to obtain a mixed solution;

[0012] (2) Immersing the ceramic membrane sheet in the mixed solution;

[0013] (3) Subjecting the ceramic membrane sheet after step (2) to pulling, drying and calcination treatments to obtain a ceramic membrane catalyst.

[0014] The third aspect of the present invention provides a ceramic membrane catalyst prepared by the aforementioned preparation method.

[0015] The fourth aspect of the present invention provides a ceramic membrane catalytic reactor, wherein the ceramic membrane catalytic reactor includes a membrane module, and the membrane module includes the aforementioned ceramic membrane catalyst.

[0016] The fifth aspect of the present invention provides an application of the aforementioned ceramic membrane catalytic reactor in acrylic acid wastewater.

[0017] Through the above technical solutions, the technical solutions of the present invention have the following beneficial effects:

[0018] (1) By screening specific catalytic components to prepare the ceramic membrane catalyst, the present invention increases the contact area between the catalyst and the wastewater, and has a higher catalytic efficiency compared with other catalytic components;

[0019] (2) The present invention uses a rotating membrane form to disperse ozone in water in the form of micro-nano bubbles, strengthening the mass transfer of ozone and improving the utilization rate of ozone;

[0020] (3) The rotating form of the membrane module of the present invention can prevent suspended solids in the sewage from depositing on the membrane surface easily. The deposited substances are easy to fall off due to friction with solids in the water under the rotating action, which can effectively reduce the fouling of the membrane sheets. Description of the Drawings

[0021] Figure 1 is a schematic diagram of the ceramic membrane catalytic reactor of the present invention;

[0022] Figure 2 is a schematic diagram of the ceramic membrane catalyst of the present invention.

[0023] Description of the Reference Numerals

[0024] In Figure 1 :

[0025] A - water inlet pump; B - pulsed water inlet pipe; C - ozone generator; D - rotating motor; E - ceramic membrane sheet; F - hollow screw; G - suction pump; H - tail gas destructor; I - separation membrane module; J - intake air membrane module;

[0026] In Figure 2 :

[0027] K - surface of the ceramic membrane catalyst; L - central circular pore channel of the ceramic membrane. Detailed Embodiments

[0028] The endpoints and any values disclosed herein in ranges are not limited to the exact ranges or values, and these ranges or values should be understood to include values close to these ranges or values. For numerical ranges, the endpoint values of each range, between the endpoint values of each range and individual point values, and between individual point values can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be regarded as specifically disclosed herein.

[0029] As described above, the first aspect of the present invention provides a ceramic membrane catalyst, wherein the ceramic membrane catalyst includes a ceramic membrane sheet and bismuth oxide supported on the ceramic membrane sheet, and the loading amount of bismuth oxide is 1-100 g / m 2 .

[0030] According to the present invention, preferably, the loading amount of bismuth oxide is 42-96 g / m 2 ; more preferably, the loading amount of bismuth oxide is 60-80 g / m 2 .

[0031] The inventors of the present invention have found that: the ceramic membrane catalyst prepared with bismuth oxide has higher catalytic efficiency for ozone catalysis; further, the use of a rotating membrane can better disperse ozone, improve the utilization rate of ozone, and reduce fouling on the surface of the membrane sheet by using the friction between the membrane sheet and the liquid during the rotation process.

[0032] According to the present invention, Figure 2 is a schematic diagram of the ceramic membrane catalyst of the present invention. It can be seen from Figure 2 that: the ceramic membrane sheet is annular, the surface K of the ceramic membrane catalyst is annular, and a circular channel - the central circular channel L of the ceramic membrane is provided in the middle of the ceramic membrane sheet; preferably, the diameter of the circular channel is 0.1-1 cm; gas and liquid can be distributed to the inside of the membrane sheet through the channel.

[0033] According to the present invention, the surface pores of the ceramic membrane sheet are 0.1-5 μm.

[0034] The second aspect of the present invention provides a preparation method of a ceramic membrane catalyst, wherein the preparation method includes:

[0035] (1) Contacting bismuth nitrate, a structure-directing agent and dilute nitric acid to obtain a mixed solution;

[0036] (2) Immersing the ceramic membrane sheet in the mixed solution;

[0037] (3) Subjecting the ceramic membrane sheet after step (2) to pulling, drying and calcination treatments to obtain a ceramic membrane catalyst.

[0038] According to the present invention, the structure-directing agent is selected from one or more of hexamethyleneimine, dehydroabietylamine, 1,8-octanediamine, and 1-butyl-3-methylimidazolium bromide.

[0039] According to the present invention, the mass ratio of the dosage of bismuth nitrate to that of the structure-directing agent is 1:(1 - 5), preferably 1:(2 - 4).

[0040] According to the present invention, the mass ratio of the dosage of bismuth nitrate to that of dilute nitric acid is 1:(5 - 20).

[0041] According to the present invention, the impregnation time is 1 - 12 h, preferably 6 - 8 h.

[0042] According to the present invention, the pulling speed is 0.5 - 5 mm / s, preferably 1 - 3 mm / s.

[0043] According to the present invention, the calcination conditions include: the calcination temperature is 500 - 800 °C, preferably 550 - 750 °C; the calcination time is 4 - 12 h, preferably 8 - 10 h.

[0044] The third aspect of the present invention provides a ceramic membrane catalyst prepared by the aforementioned preparation method.

[0045] The fourth aspect of the present invention provides a ceramic membrane catalytic reactor, wherein the ceramic membrane catalytic reactor includes a membrane module, and the membrane module includes the aforementioned ceramic membrane catalyst.

[0046] According to the present invention, Figure 1 is a schematic diagram of the ceramic membrane catalytic reactor of the present invention, as Figure 1 shown:

[0047] According to the present invention, the water inlet pump A is connected to the pulsed water inlet pipe B through a pipeline, and the water is distributed through the pulsed water inlet pipe B under the action of the water inlet pump A.

[0048] According to the present invention, the ozone generator C is connected to the air inlet membrane module J through a pipeline, ozone is generated in the ozone generator C, and is distributed in the reactor through the air inlet membrane module J.

[0049] According to the present invention, the membrane module includes an air inlet membrane module J and a separation membrane module I.

[0050] According to the present invention, the membrane module is composed of the ceramic membrane sheet E prepared above, a rotating motor D, a hollow screw F, and a screw connecting piece.

[0051] According to the present invention, the hollow screw F of the air inlet membrane module is connected to the gas pipeline, and the hollow screw of the separation membrane module I is connected to the water outlet pipeline; preferably, the hollow screw is connected to the rotating electrode D through a screw connecting piece.

[0052] The hollow screw F is provided with a circular opening for the passage of gas and liquid; the circular pore L of the ceramic diaphragm E is aligned with the opening of the hollow screw and is connected by a seal.

[0053] According to the present invention, a ceramic diaphragm E is sleeved on the hollow screw F.

[0054] According to the present invention, the hollow screw of the separation membrane assembly I is connected to the suction pump G through a water outlet pipe.

[0055] According to the present invention, the tail gas of the reactor is post-treated and discharged through a tail gas destroyer H.

[0056] According to the present invention, the rotational speeds of the intake air membrane assembly and the separation membrane assembly are each 200 - 500 r / min, preferably 300 - 450 r / min.

[0057] The fifth aspect of the present invention provides an application of the aforementioned ceramic membrane catalytic reactor in acrylic acid wastewater.

[0058] In the present invention, the application of the ceramic membrane catalytic reactor in acrylic acid wastewater includes:

[0059] (S1) The acrylic acid production wastewater enters each branch pipe through the main inlet pipe. Each branch pipe is provided with a valve. When water enters, the first valve is opened for 5 - 10 minutes first, and then the first valve is closed and the second valve is opened, and so on for pulsed water distribution.

[0060] (S2) After the wastewater enters the reactor, it is mixed under the action of pulsed water distribution; ozone enters the intake air membrane assembly through the intake pipe. The intake air membrane assembly is driven by a motor to rotate. Ozone enters the water body through the pores on the ceramic diaphragm, and ozone dissolves or exists in the form of micro - nano bubbles. Part of the pollutants in the water body are adsorbed on the ceramic membrane catalyst.

[0061] (S3) Under the action of the ceramic membrane catalyst, the organic pollutants in the water body undergo an oxidation reaction with ozone and the hydroxyl radicals generated by its decomposition, and the sewage is purified.

[0062] (S4) The treated wastewater enters the water outlet pipe through the pores on the surface of the separation membrane assembly under the action of the suction pump, and the suspended solids in the water are intercepted by the separation membrane assembly in the reactor.

[0063] According to the present invention, the components of the acrylic acid production wastewater include acrylic acid, acrolein, acetic acid, maleic acid, allyl alcohol, formaldehyde, hydroquinone, etc. The COD of the wastewater is 500 - 3000 mg / L.

[0064] The present invention will be described in detail below through examples.

[0065] In the following examples and comparative examples:

[0066] The COD parameter was measured by the method of "Determination of Chemical Oxygen Demand in Water - Dichromate Method" (HJ 828 - 2017).

[0067] The bismuth nitrate raw material was a commercially available product of bismuth nitrate pentahydrate (CAS No. 10035 - 06 - 0) from Xilong Scientific Co., Ltd.

[0068] The hexamethyleneimine raw material was a commercially available product with the product number H157403 from Shanghai Aladdin Biochemical Technology Co., Ltd.

[0069] The dehydroabietylamine was a commercially available product from Wuhan Jixin Yibang Biotechnology Co., Ltd.

[0070] The ceramic membrane was a commercially available product from Shanghai Keyu Water Treatment Technology Co., Ltd.

[0071] Example 1

[0072] (1) Using a ring - shaped ceramic membrane with a pore size of 2 μm (the diameter of the circular pore is 0.5 cm) as the catalyst carrier, and hexamethyleneimine as the structure - guiding agent, where the mass ratio of bismuth nitrate to hexamethyleneimine is 1:3, and the mass ratio of bismuth nitrate to dilute nitric acid is 1:15, to obtain a mixed solution;

[0073] (2) Immersing the ceramic membrane in the mixed solution; the immersion time is 7 h;

[0074] (3) After the ceramic membrane in step (2) is lifted at a speed of 2 mm / s, it is dried at a drying temperature of 30 °C, and then calcined in air for 8 h at a calcination temperature of 650 °C to prepare a bismuth oxide ceramic membrane catalyst.

[0075] Among them, the ceramic membrane catalyst includes a ceramic membrane and bismuth oxide loaded on the ceramic membrane, and the loading amount of bismuth oxide is 74 g / m 2 .

[0076] Using the above - mentioned ceramic membrane catalyst to make a ceramic membrane catalytic reactor, which is a rotating ceramic membrane catalytic reactor, for treating acrylic acid production wastewater (acrylic acid content is 0.05%, formaldehyde content is 0.015). Before treatment, the COD of the acrylic acid production wastewater is 2839 mg / L. Under the conditions of a treatment water volume of 5 L, an ozone concentration of 130 mg / L, and an ozone gas flow rate of 1.5 L / min, the treatment effect of the rotating ceramic membrane catalytic reactor is shown in Table 1.

[0077] Comparative Example 1

[0078] The acrylic acid production wastewater was treated in the same manner as in Example 1, except that the "rotating ceramic membrane catalytic reactor" was replaced with a "stationary ceramic membrane catalytic reactor". The stationary ceramic membrane catalytic reactor has no other differences from the rotating ceramic membrane catalytic reactor except that the ceramic membrane sheets are stationary.

[0079] The treatment effect of the stationary ceramic membrane catalytic reactor is shown in Table 1.

[0080] Comparative Example 2

[0081] The acrylic acid production wastewater was treated in the same manner as in Example 1, except that the "rotating ceramic membrane catalytic reactor" was replaced with a "rotating ceramic membrane reactor. The ceramic membrane sheets of this rotating ceramic membrane reactor are the same as those in Example 1 and do not carry a catalyst.

[0082] The treatment effect of the rotating ceramic membrane reactor is shown in Table 1.

[0083] Comparative Example 3

[0084] The acrylic acid production wastewater was treated in the same manner as in Example 1, except that the "rotating ceramic membrane catalytic reactor" was replaced with a "stationary ceramic membrane reactor. The ceramic membrane sheets of this stationary ceramic membrane reactor are the same as those in Example 1, do not carry a catalyst, do not rotate, and remain stationary.

[0085] The treatment effect of the stationary ceramic membrane catalytic reactor is shown in Table 1.

[0086] Example 2

[0087] (1) An annular ceramic membrane sheet with a pore size of 2 μm (the diameter of the circular pore channel is 0.5 cm) was used as a catalyst carrier, and dehydroabietylamine was used as a structure-directing agent. Among them, the mass ratio of bismuth nitrate to dehydroabietylamine was 1:3, and the mass ratio of bismuth nitrate to dilute nitric acid was 1:10 to obtain a mixed solution;

[0088] (2) The ceramic membrane sheet was immersed in the mixed solution; among them, the immersion time was 7 h;

[0089] (3) After the ceramic membrane sheet in step (2) was lifted at a speed of 2.5 mm / s, it was dried at a drying temperature of 30 °C and then calcined in air for 8 h at a calcination temperature of 650 °C to prepare a bismuth oxide ceramic membrane catalyst.

[0090] Among them, the ceramic membrane catalyst includes a ceramic membrane sheet and bismuth oxide loaded on the ceramic membrane sheet, and the loading amount of bismuth oxide is 42 g / m 2 .

[0091] Using the above-mentioned ceramic membrane catalyst to fabricate a ceramic membrane catalytic reactor, which is a rotating ceramic membrane catalytic reactor. For a certain acrylic acid production wastewater (with an acrylic acid content of 0.1%), the COD of the acrylic acid production wastewater before treatment is 2839 mg / L. Under the conditions of a treatment water volume of 5 L, an ozone concentration of 150 mg / L, and an ozone gas flow rate of 2 L / min, the treatment effect of the rotating ceramic membrane catalytic reactor is shown in Table 1.

[0092] Example 3

[0093] (1) Using an annular ceramic membrane sheet with a pore size of 2 μm (the diameter of the circular pore is 0.5 cm) as the catalyst carrier, and using dehydroabietylamine as the structure-directing agent. Among them, the mass ratio of bismuth nitrate to dehydroabietylamine is 1:3, and the mass ratio of bismuth nitrate to dilute nitric acid is 1:20 to obtain a mixed solution;

[0094] (2) Immerse the ceramic membrane sheet in the mixed solution; among them, the immersion time is 7 h;

[0095] (3) After the ceramic membrane sheet in step (2) is lifted at a speed of 2.5 mm / s, it is dried at a drying temperature of 30 °C, and then calcined in air for 8 h at a calcination temperature of 650 °C to prepare a bismuth oxide ceramic membrane catalyst.

[0096] Among them, the ceramic membrane catalyst includes a ceramic membrane sheet and bismuth oxide supported on the ceramic membrane sheet, and the loading amount of bismuth oxide is 96 g / m 2 .

[0097] Using the above-mentioned ceramic membrane catalyst to fabricate a ceramic membrane catalytic reactor, which is a rotating ceramic membrane catalytic reactor. For a certain acrylic acid production wastewater (with an acrylic acid content of 0.1%), the COD of the acrylic acid production wastewater before treatment is 2839 mg / L. Under the conditions of a treatment water volume of 5 L, an ozone concentration of 150 mg / L, and an ozone gas flow rate of 2 L / min, the treatment effect of the rotating ceramic membrane catalytic reactor is shown in Table 1.

[0098] Comparative Example 4

[0099] (1) Using an annular ceramic membrane sheet with a pore size of 2 μm (the diameter of the circular pore is 0.5 cm) as the catalyst carrier, and using dehydroabietylamine as the structure-directing agent. Among them, the mass ratio of bismuth nitrate to dehydroabietylamine is 1:3, and the mass ratio of bismuth nitrate to dilute nitric acid is 1:25 to obtain a mixed solution;

[0100] (2) Immerse the ceramic membrane sheet in the mixed solution; among them, the immersion time is 7 h;

[0101] (3) After the ceramic membrane sheet obtained in step (2) is lifted at a speed of 2.5 mm / s, it is dried at a drying temperature of 30 °C, and then calcined in air for 8 h at a calcination temperature of 650 °C to prepare a bismuth oxide ceramic membrane catalyst.

[0102] Among them, the ceramic membrane catalyst includes a ceramic membrane sheet and bismuth oxide supported on the ceramic membrane sheet, and the loading amount of bismuth oxide is 112 g / m 2 .

[0103] Using the above ceramic membrane catalyst to fabricate a ceramic membrane catalytic reactor, which is a rotating ceramic membrane catalytic reactor. For a certain acrylic acid production wastewater (acrylic acid content is 0.1%), the COD of the acrylic acid production wastewater before treatment is 2839 mg / L. Under the conditions of a treatment water volume of 5 L, an ozone concentration of 150 mg / L, and an ozone gas flow rate of 2 L / min, the treatment effect of the rotating ceramic membrane catalytic reactor is shown in Table 1.

[0104] Comparative Example 5

[0105] (1) Using an annular ceramic membrane sheet with pores of 2 μm (the diameter of the circular pores is 0.5 cm) as the catalyst carrier, dehydroabietylamine as the structure-directing agent, and manganese oxide as the catalyst. Among them, the mass ratio of manganese nitrate to dehydroabietylamine is 1:3, and the mass ratio of manganese nitrate to dilute nitric acid is 1:15 to obtain a mixed solution;

[0106] (2) Immerse the ceramic membrane sheet in the mixed solution; among them, the immersion time is 7 h;

[0107] (3) After the ceramic membrane sheet obtained in step (2) is lifted at a speed of 2.5 mm / s, it is dried at a drying temperature of 30 °C, and then calcined in air for 8 h at a calcination temperature of 650 °C to prepare a manganese oxide ceramic membrane catalyst.

[0108] Among them, the ceramic membrane catalyst includes a ceramic membrane sheet and manganese oxide supported on the ceramic membrane sheet, and the loading amount of manganese oxide is 68 g / m 2 .

[0109] Using the above ceramic membrane catalyst to fabricate a ceramic membrane catalytic reactor, which is a rotating ceramic membrane catalytic reactor. For a certain acrylic acid production wastewater (acrylic acid content is 0.1%), the COD of the acrylic acid production wastewater before treatment is 2839 mg / L. Under the conditions of a treatment water volume of 5 L, an ozone concentration of 150 mg / L, and an ozone gas flow rate of 2 L / min, the treatment effect of the rotating ceramic membrane catalytic reactor is shown in Table 1.

[0110] Table 1

[0111]

[0112]

[0113] As can be seen from the results in Table 1, the present invention uses a supported ceramic membrane catalyst to enhance the dissolution of ozone, improve the utilization rate of ozone, reduce the operating cost of the ozone process, and improve the treatment effect of the ozone process.

[0114] In Comparative Example 1, since the ceramic membrane in the static ceramic membrane catalytic reactor is stationary, the dissolution rate and effect of ozone in water are not as good as those in Example 1, and the utilization rate of ozone is not as good as that in Example 1. Therefore, the overall treatment effect is not good.

[0115] In Comparative Example 2, since the rotating ceramic membrane reactor is not loaded with a catalyst, although the dissolution rate and effect of ozone are the same as those in Example 1, due to the absence of a catalyst, the oxidation efficiency of ozone is not as good as that in Example 1. Therefore, the overall treatment effect is not good.

[0116] In Comparative Example 3, since the ceramic membrane in the static ceramic membrane reactor does not rotate, the dissolution rate and effect of ozone are not as good as those in Example 1. At the same time, due to the absence of a catalyst on the ceramic membrane, the oxidation efficiency of ozone is not as good as that in Example 1. Therefore, the overall treatment effect is not good.

[0117] In Comparative Example 4, since there is too much catalyst loaded on the ceramic membrane, the adsorption pores on the ceramic membrane are occupied, resulting in a decrease in the adsorption amount of pollutants on the membrane and a reduction in the contact probability with ozone. Therefore, the overall treatment effect is not good.

[0118] In Comparative Example 5, since the supported catalyst is manganese oxide, its catalytic effect is not as good as that of bismuth oxide. Therefore, the overall treatment effect is not good.

[0119] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited thereto. Within the technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention, including any other suitable combination of each technical feature. These simple modifications and combinations should also be regarded as the content disclosed by the present invention and fall within the protection scope of the present invention.

Claims

1. A ceramic membrane catalyst, characterized in that, The ceramic membrane catalyst includes a ceramic membrane sheet and bismuth oxide supported on the ceramic membrane sheet, and the loading amount of the bismuth oxide is 1-100 g / m 2 .

2. The ceramic membrane catalyst according to claim 1, wherein, The loading amount of the bismuth oxide is 60 - 80 g / m 2 .

3. The ceramic membrane catalyst according to claim 1 or 2, wherein The ceramic diaphragm is annular, and a circular channel is provided in the middle of the ceramic diaphragm; Preferably, the diameter of the circular channel is 0.1 - 1 cm; And / or, the surface pores of the ceramic diaphragm are 0.1 - 5 μm.

4. A preparation method of a ceramic membrane catalyst, characterized in that, The preparation method includes: (1) Contacting bismuth nitrate, a structure-directing agent, and dilute nitric acid to obtain a mixed solution; (2) Immersing the ceramic diaphragm in the mixed solution; (3) Subjecting the ceramic diaphragm after step (2) to pulling, drying, and calcination treatments to obtain a ceramic membrane catalyst.

5. The preparation method according to claim 4, wherein, The structure-directing agent is selected from one or more of hexamethyleneimine, dehydroabietylamine, 1,8-octanediamine, and 1-butyl-3-methylimidazolium bromide.

6. The preparation method according to claim 4, wherein, The mass ratio of the amounts of bismuth nitrate and the structure-directing agent is 1:(1 - 5), preferably 1:(2 - 4); And / or, the mass ratio of the amounts of bismuth nitrate and the dilute nitric acid is 1:(5 - 20).

7. The preparation method according to claim 4, wherein, The immersion time is 1 - 12 h, preferably 6 - 8 h; And / or, the pulling speed is 0.5 - 5 mm / s, preferably 1 - 3 mm / s; And / or, the calcination conditions include: the calcination temperature is 500 - 800 °C, preferably 550 - 750 °C; the calcination time is 4 - 12 h, preferably 8 - 10 h.

8. A ceramic membrane catalyst prepared by the preparation method according to any one of claims 4 - 7.

9. A ceramic membrane catalytic reactor, characterized in that, The ceramic membrane catalytic reactor includes a membrane module, and the membrane module includes the ceramic membrane catalyst according to any one of claims 1 - 3 and 8.

10. The ceramic membrane catalytic reactor according to claim 9, wherein, The membrane module includes an intake air membrane module and a separation membrane module.

11. The ceramic membrane catalytic reactor according to claim 9 or 10, wherein, The hollow screw of the intake air membrane module is connected to a gas pipeline, and the hollow screw of the separation membrane module is connected to a water outlet pipeline; Preferably, the hollow screw is connected to a rotating electrode through a screw connector; And / or, a circular opening is provided on the hollow screw for the passage of gas and liquid; the circular channel of the ceramic diaphragm is aligned with the opening of the hollow screw and is connected through a seal; And / or, a ceramic diaphragm is sleeved on the hollow screw; And / or, the hollow screw of the separation membrane module is connected to a suction pump through a water outlet pipeline; And / or, the rotational speeds of the intake air membrane module and the separation membrane module are each 200 - 500 r / min, preferably 300 - 450 r / min.

12. Use of the ceramic membrane catalytic reactor according to any one of claims 9 - 11 in acrylic acid wastewater.

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