A cermet composite structure film and a preparation method and application thereof

Abstract

The application discloses a cermet composite structure film and a preparation method and application thereof, and belongs to the technical field of composite film preparation. First, the foam metal net is cut to a target size, ultrasonic cleaning and drying are performed; then, the foam metal net is immersed in a slurry containing metal oxides, and is dried to obtain a porous metal net covered with metal oxides; ceramic powder, a solvent and an adhesive are mixed to prepare a ceramic powder slurry; the ceramic powder slurry is filled in the pores of the porous metal net through a vacuum suction method, and is dried and dry-pressed to form a film, and the film is sintered in an inert atmosphere containing hydrogen to obtain the cermet composite structure film. The prepared cermet composite structure film maximally reduces the volume proportion of the metal phase (<10%) under the premise of keeping the metal phase connected, thereby enhancing the function (such as conducting oxygen ions, protons and the like) of the ceramic phase, and meanwhile, the cermet composite structure has high mechanical strength, and has a good application prospect in a mixed conductor film reactor.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of composite film preparation, and particularly relates to a cermet composite structure film and a preparation method and application thereof. BACKGROUND

[0002] The catalytic membrane reactor can realize reaction-separation coupling, can simplify the operation process, reduce production cost, and promote the reaction process, and has the advantages of continuous operation and low energy consumption. According to the difference in the phase composition of the membrane material, the catalytic membrane reactor can be roughly divided into a single-phase membrane reactor and a dual-phase membrane reactor, and the dual-phase membrane reactor has higher mechanical strength and chemical stability.

[0003] At present, the dual-phase membrane material is mainly prepared by mechanically mixing powders of two phases, and then dry pressing, flow casting and sintering. Taking the mixed oxygen ion-electronic conductor oxygen permeation membrane reactor as an example, since the electronic conductivity of the membrane material is generally much higher than the oxygen ion conductivity, in order to improve the permeation performance of the oxygen permeation membrane, the volume ratio of the electronic conductor phase needs to be reduced as much as possible. In order to enable the oxygen permeation membrane to work normally, a continuous electronic conductor phase needs to be formed in the membrane body phase to balance the charge in the oxygen ion transmission process, so the electronic conductor phase and the oxygen ion conductor phase need to form a continuous conductive phase. Studies have shown that the dual-phase membrane formed by mechanical mixing needs the volume ratio of each phase to be greater than or equal to 30% to form a continuous conductive phase. Therefore, the volume ratio of the low-conductivity phase (such as the oxygen ion conductor phase) in the dual-phase membrane is at most 70%, and when the volume ratio of one phase is small, a closed area is easily formed in the membrane body phase, thereby losing part of the electrical conductivity of the dual-phase membrane material. SUMMARY

[0004] In view of this, the purpose of the present application is to provide a cermet composite structure film and a preparation method and application thereof. The present application fills ceramic powder in the pores of the foam metal directly, and then dry-presses and sinteres to obtain a dense dual-phase membrane. Since the electronic conductivity of the metal material is more than 10,000 times the oxygen ion conductivity of the ceramic material, in order to improve the permeation performance of the dual-phase membrane, the volume ratio of the ceramic phase in the cermet composite structure film of the present application can be significantly higher than the highest volume ratio of 70% of the ceramic phase in the traditional dual-phase membrane preparation method.

[0005] In order to achieve the above-mentioned purpose, the present application provides the following technical scheme:

[0006] The present application provides a preparation method of a cermet composite structure film, comprising the following steps:

[0007] (1) cutting a foam metal mesh into a porous metal mesh of a target size, ultrasonic cleaning and drying;

[0008] (2) immerse the porous metal mesh in step (1) in a slurry containing metal oxide for 5-60s, dry, to obtain a porous metal mesh covered with metal oxide on the surface;

[0009] (3) mix the ceramic powder with a solvent and a binder, heat to 40-80℃, stir for 1-4h, to obtain a ceramic powder slurry;

[0010] (4) fill the ceramic powder slurry in step (3) into the pores of the porous metal mesh in step (2) by vacuum filtration, dry to obtain a green body;

[0011] (5) dry-press the green body obtained in step (4), then sinter in an inert atmosphere containing hydrogen at 1000-1500℃, to obtain a dense cermet composite structure film.

[0012] Based on the above technical solution, further, the metal mesh in step (1) is a nickel mesh, a copper mesh or a stainless steel mesh.

[0013] Based on the above technical solution, further, the metal oxide in step (2) is nickel oxide, copper oxide or manganese oxide, and the mass ratio of metal oxide, polyvinyl butyral and solvent in the slurry containing metal oxide is 1:0.5-2:10-100.

[0014] Based on the above technical solution, further, the solvent in step (2) is methanol or ethanol.

[0015] Based on the above technical solution, further, the ceramic powder in step (3) is yttria-stabilized zirconia or samarium-doped ceria.

[0016] Based on the above technical solution, further, the solvent in step (3) is deionized water.

[0017] Based on the above technical solution, further, the binder in step (3) is gum arabic.

[0018] Based on the above technical solution, further, the mass ratio of the ceramic powder slurry, the solvent and the binder in step (3) is 1:0.005-0.1:1-10.

[0019] Based on the above technical solution, further, the dry-pressing pressure in step (5) is 100-300MPa.

[0020] Based on the above technical solution, further, the volume percentage of hydrogen in the inert atmosphere containing hydrogen in step (5) is 4-10%.

[0021] Based on the above technical solution, further, the sintering time in step (5) is 2-10h.

[0022] Another aspect of the present application provides the cermet composite structure film prepared by the above method.

[0023] The present application also provides the use of the above cermet composite structure film in a mixed conductor membrane reactor.

[0024] Compared with the prior art, the present application has the following advantages:

[0025] 1) The volume fraction of the metal phase in the cermet composite structure film of the present application can be reduced to within 5%, thereby greatly increasing the volume fraction of the ceramic phase and enhancing the overall performance of the mixed conductor membrane reactor.

[0026] 2) The mechanical strength of the cermet composite structure film of the present application is higher than that of the ceramic-ceramic two-phase structure film. BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced as follows:

[0028] Figure 1 : Schematic diagram of the traditional two-phase mixed conductor membrane body phase structure;

[0029] Figure 2 : Schematic diagram of the cermet composite structure film of the present application;

[0030] Figure 3 : Cross-sectional micro-morphology of the cermet composite structure film prepared in Example 1;

[0031] Figure 4 : Surface micro-morphology of the cermet composite structure film prepared in Example 1. DETAILED DESCRIPTION

[0032] The present application will be further described in detail below in conjunction with specific embodiments, and the embodiments given are only for the purpose of illustrating the present application, but not for limiting the scope of the present application.

[0033] Without departing from the design idea of the present application, various modifications and changes can be made to the specific embodiments of the present application, which will be apparent to those skilled in the art.

[0034] Example 1

[0035] The present embodiment provides a preparation method of a cermet composite structure film, comprising the following steps:

[0036] (1) Cut 1.5 mm thick foamed nickel into a circular sheet with a diameter of 18 mm, and then clean it with deionized water and anhydrous ethanol under ultrasonic wave, and dry it for use;

[0037] (2) Put 3.01 g of manganese dioxide powder, 2.41 g of polyvinyl butyral, and 54.5 g of ethanol into a magnetic stirrer and stir for 2 h to obtain a manganese dioxide slurry; immerse the dried nickel foam in the manganese dioxide slurry for 10 s, and dry after taking out;

[0038] (3) Put 6.01 g of YSZ (yttria-stabilized zirconia) powder, 0.10 g of gum arabic, and 14.01 g of deionized water into a magnetic stirrer, heat the magnetic stirrer to 60°C, and stir for 2 h to obtain a YSZ slurry;

[0039] (4) Put the nickel foam immersed with manganese dioxide and the YSZ slurry after drying into a Buchner funnel, vacuum filter, and dry after taking out to obtain a green body of nickel foam-YSZ material;

[0040] (5) Put the obtained green body of nickel foam-YSZ material into a mold under a pressure of 200 MPa, then put it into a tube furnace, heat to 1400°C in a 5 vol.% H2-Ar mixed gas at a flow rate of 60 mL / min, and keep for 6 h, and obtain the final nickel foam-YSZ cermet composite structure film after cooling.

[0041] Brush nickel-based catalyst on both sides of the obtained cermet composite structure film, supply a mixed gas of helium and water (10% He, 90% H2O) at a flow rate of 200 mL / min -1 on the supply side and a mixed gas of argon and hydrogen (50% Ar-50% H2) at a flow rate of 100 mL / min -1 on the permeation side, and the hydrogen generation rate measured on the supply side is 1.02 mL cm -2 min -1 .

[0042] Example 2

[0043] The embodiment provides a preparation method of a cermet composite structure film, comprising the following steps:

[0044] (1) Cut 1.5 mm thick nickel foam into a circular piece with a diameter of 18 mm, ultrasonically clean with deionized water and anhydrous ethanol, and dry for use.

[0045] (2) Put 1.51 g of manganese dioxide powder, 2.41 g of polyvinyl butyral, and 54.5 g of ethanol into a magnetic stirrer and stir for 2 h to obtain a manganese dioxide slurry; immerse the dried nickel foam in the manganese dioxide slurry for 10 s, and dry after taking out;

[0046] (3) Put 6.01 g of YSZ powder, 0.05 g of gum arabic, and 14.01 g of deionized water into a magnetic stirrer, heat the magnetic stirrer to 60°C, and stir for 2 h to obtain a YSZ slurry;

[0047] (4) Place the dried nickel foam impregnated with manganese dioxide and YSZ slurry into a Buchner funnel, vacuum filter, remove and dry to obtain nickel foam-YSZ material green blank.

[0048] (5) The obtained nickel-YSZ foam material blank was formed under a pressure of 200MPa, and then placed in a tube furnace. It was heated to 1400℃ in a 5vol.% H2-Ar mixed gas at a rate of 60mL / min and held for 6h. After cooling, the final nickel-YSZ metal-ceramic composite structure membrane was obtained.

[0049] Nickel-based catalyst was brush-coated onto both sides of the obtained metal-ceramic composite membrane, and 200 mL of catalyst was introduced into the feed side at 900 °C. -1 A mixture of helium and water (10% He, 90% H2O) is introduced into the permeate side at a rate of 100 mL / min. -1 A mixture of argon and hydrogen (50% Ar - 50% H2) was used, and the hydrogen production rate, measured on the supply side, was 0.79 mL / cm². -2 min -1 .

[0050] Example 3

[0051] This embodiment provides a method for preparing a metal-ceramic composite structure membrane, including the following steps:

[0052] (1) Cut 1.5mm thick nickel foam into round pieces with a diameter of 18mm, clean them ultrasonically with deionized water and anhydrous ethanol, and then dry them for later use.

[0053] (2) 3.01g of nickel oxide powder, 2.41g of polyvinyl butyral and 54.5g of ethanol were placed in a magnetic stirrer and stirred for 2 hours to obtain nickel oxide slurry; the dried nickel foam was immersed in the nickel oxide slurry for 10 seconds, and then removed and dried.

[0054] (3) Place 6.01g of SDC (samarium-doped cerium oxide) powder, 0.10g of gum arabic and 14.01g of deionized water into a magnetic stirrer, heat the magnetic stirrer to 60°C and stir for 2 hours to obtain SDC slurry;

[0055] (4) Place the dried nickel foam impregnated with manganese dioxide and SDC slurry into a Buchner funnel, vacuum filter, remove and dry to obtain nickel foam-SDC material green blank.

[0056] (5) The green body of the obtained nickel-SDC foam material was shaped under a pressure of 200 MPa, and then was placed in a tube furnace and heated to 1400°C in 5 vol.% H2-Ar mixed gas at a flow rate of 60 mL / min, and was kept for 6 h. After cooling, the final nickel-SDC cermet composite structure film was obtained.

[0057] A nickel-based catalyst was brushed on both sides of the obtained cermet composite structure film. At 900°C, a mixed gas of helium and water (10% He, 90% H2O) was supplied to the supply side at a flow rate of 200 mL / min -1 , and a mixed gas of argon and hydrogen (50% Ar-50% H2) was supplied to the permeation side at a flow rate of 100 mL / min -1 . The hydrogen generation rate measured on the supply side was 0.92 mL cm -2 min -1 .

Claims

1. A method for producing a cermet composite structure film, characterized by, The method comprises the following steps: (1) cutting the foamed metal mesh into a porous metal mesh of a target size, ultrasonic cleaning, and drying; (2) immersing the porous metal mesh in step (1) in a slurry containing metal oxides for 5-60 s, and drying to obtain a porous metal mesh covered with metal oxides on the surface; (3) mixing ceramic powder, a solvent, and an adhesive, heating to 40-80 ℃, and stirring for 1-4 h to prepare a ceramic powder slurry; (4) filling the ceramic powder slurry in step (3) into the pores of the porous metal mesh in step (2) by vacuum filtration, and drying to obtain a green body; (5) dry pressing the green body obtained in step (4), and then sintering in an inert atmosphere containing hydrogen at 1000-1500 ℃ to obtain a dense cermet composite structure film; The metal oxide in step (2) is nickel oxide, copper oxide, or manganese oxide. The ceramic powder in step (3) is yttrium-stabilized zirconia or samarium-doped ceria.

2. The production method according to claim 1, characterized by, The metal mesh in step (1) is a nickel mesh, a copper mesh, or a stainless steel mesh.

3. The production method according to claim 1, characterized by, The mass ratio of the metal oxide, polyvinyl butyral, and the solvent in the slurry containing metal oxides in step (2) is 1:0.5-2:10-100.

4. The method of claim 1, wherein, The solvent in step (3) is deionized water; and the adhesive is gum arabic.

5. The preparation method according to claim 4, characterized in that, The mass ratio of the ceramic powder slurry, the solvent, and the adhesive in step (3) is 1:0.005-0.1:1-10.

6. The method of claim 1, wherein, The dry pressing pressure in step (5) is 100-300 MPa.

7. The preparation method according to claim 1, characterized in that, The volume percentage of hydrogen in the inert atmosphere containing hydrogen in step (5) is 4-10%.

8. The method of claim 1, wherein, The sintering time in step (5) is 2-10 h.

9. The cermet composite structure film prepared by the preparation method in any one of claims 1-8.

10. The cermet composite structure film in claim 9 for use in a mixed conductor membrane reactor.

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