Hybrid hydrogen separation membrane filled with organic polymer by using metal foam titanium as framework and preparation method and application thereof

Abstract

This invention discloses a hybrid hydrogen separation membrane with a titanium foam framework and an organic polymer filling, along with its preparation method and applications. It relates to the field of hydrogen separation membrane preparation technology and specifically includes the following steps: S1: pretreatment of the titanium foam material; S2: preparation of a homogeneous polybenzimidazole solution as the filling material; S3: preparation of titanium foam internally filled with polybenzimidazole; S4: preparation of a titanium foam hybrid membrane internally filled with polybenzimidazole and phosphoric acid crosslinked; S5: loading Pt particle catalysts onto both sides of the titanium foam hybrid membrane internally filled with polybenzimidazole and phosphoric acid crosslinked by ion sputtering. The titanium foam-organic polymer hybrid membrane of this invention exhibits high hydrogen selectivity, significantly improving the hydrogen permeation flux.

Description

Technical Field

[0001] This invention relates to the field of hydrogen separation membrane preparation technology, specifically to a hybrid hydrogen separation membrane with a titanium foam framework filled with organic polymers, its preparation method, and its application. Background Technology

[0002] Currently, hydrogen energy, as a highly promising clean energy source, is receiving increasing attention worldwide. It is regarded as a key link in achieving global energy transition, addressing climate change, and reaching carbon neutrality goals, but its large-scale commercialization still faces many challenges.

[0003] Hydrogen production includes methods such as fossil fuel reforming, water electrolysis, and industrial byproduct production. Fossil fuel reforming is the primary source of hydrogen, but this method generates impurities. Therefore, separating high-purity hydrogen has become crucial for enhancing market competitiveness. Compared to methods like pressure swing adsorption, cryogenic condensation, and cryogenic separation, membrane separation offers advantages such as lower investment costs, lower energy consumption, and ease of scalability. Among various hydrogen separation membranes, organic polymer membranes typically struggle to simultaneously possess high permeability and selectivity.

[0004] Therefore, it is of great significance to provide a hybrid membrane with high H2 permeation flux. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a hybrid hydrogen separation membrane with a titanium foam framework filled with organic polymers, along with its preparation method and applications. The hybrid hydrogen separation membrane prepared by this invention, with a titanium foam framework filled with organic polymers, exhibits high hydrogen permeation flux at lower temperatures, thus solving the problem of poor H2 permeability of traditional organic membranes.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: This invention provides a method for preparing a hybrid hydrogen separation membrane with a titanium foam framework filled with an organic polymer, specifically comprising the following steps: S1: Pretreatment of titanium foam material; S2: Dissolve the dried polybenzimidazole (OPBI) powder by heating and stirring with N,N-dimethylacetamide (DMAC) to obtain a homogeneous polybenzimidazole solution as a filler material; S3: The pretreated titanium foam is immersed in a homogeneous polybenzimidazole solution and dried under vacuum to obtain titanium foam filled with polybenzimidazole. S4: Immerse the foamed titanium filled with polybenzimidazole in a phosphoric acid (PA) solution at room temperature for a period of time and then dry it to obtain a foamed titanium hybrid film filled with polybenzimidazole and phosphoric acid crosslinked, namely Ti-OPBI-PA. S5: Pt particle catalysts are loaded on both sides of a foam titanium hybrid membrane filled with crosslinked polybenzimidazole and phosphoric acid by ion sputtering, thus forming a hybrid hydrogen separation membrane with metal foam titanium as the framework and organic polymers as the filling.

[0007] Further, in step S1, the pretreatment is as follows: cut the foamed titanium into round pieces, place them in acetone, add hydrochloric acid in a deionized water solution, and ethanol for ultrasonic cleaning, and then dry them to complete the pretreatment.

[0008] Furthermore, the pretreatment specifically involves: cutting 0.6 mm thick titanium foam into 1.5 cm diameter discs, first ultrasonically cleaning them in acetone solution for 30 min, then ultrasonically cleaning them in a deionized water solution with added hydrochloric acid at pH 5 for 20 min, and finally ultrasonically cleaning them alternately in ethanol, deionized water, ethanol, deionized water, and ethanol, each time for 20 min, and drying them to complete the pretreatment; the ultrasonic power is 50 Hz.

[0009] Further, in step S2, the ratio of N,N-dimethylacetamide to polybenzimidazole powder is 10 mL: 0.9 g; the temperature for heating and stirring is 50 °C, the stirring speed is 300 r / min, and the stirring time is 12 h.

[0010] Further, in step S3, step S3 specifically includes: S31: Immerse the pretreated titanium foam material in a homogeneous polybenzimidazole solution and vacuum dry it for a period of time; S32: Transfer the foamed titanium to a drying oven and heat it to dry; S33: Remove the foamed titanium and gently wipe the surface with filter paper to remove excess solution; S34: Place the lightly wiped foam titanium into a drying oven and heat it to dry; S35: Repeat steps S32-S34 two to three times to obtain foam titanium filled with polybenzimidazole.

[0011] Furthermore, in step S31, the vacuum degree is 13.0 kPa, and the vacuum drying is carried out at 30°C for 2 hours; in step S32, the temperature drying is carried out at 60°C for 2 hours; and in step S34, the temperature drying is carried out at 80°C for 2 hours.

[0012] Further, step S4 specifically involves immersing the foamed titanium filled with polybenzimidazole in an 85% phosphoric acid solution at room temperature for 12 hours. After immersion, the foamed titanium is removed and placed in an oven at 80°C for 2 hours to dry, thereby obtaining a foamed titanium hybrid film filled with polybenzimidazole and phosphoric acid crosslinked together.

[0013] Further, step S5 specifically involves placing a foam titanium hybrid membrane filled with crosslinked polybenzimidazole and phosphoric acid on the operating stage of an ion sputtering instrument and performing a platinum sputtering operation to load Pt catalysts on both surfaces of the membrane, thus forming a hybrid hydrogen separation membrane with metal foam titanium as the framework and filled with organic polymers.

[0014] The present invention also provides a hybrid hydrogen separation membrane with an organic polymer filled in a titanium foam framework, prepared by the above preparation method.

[0015] The present invention also provides the application of a hybrid hydrogen separation membrane with a titanium foam framework filled with an organic polymer, the hybrid hydrogen separation membrane being used for H2 separation.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: In this invention, a hybrid membrane of organic polymer-filled titanium foam with high hydrogen permeation flux and selectivity is ingeniously designed by combining traditional organic polymer membranes and inorganic membranes. Firstly, the organic polymer polybenzimidazole used in this invention can fully fill the interior of the titanium foam with its micropores under capillary action, making full use of organic matter to achieve H… + and e - The internal dual-channel structure enables high selectivity for H2. Secondly, the foamed titanium exhibits good acid and alkali resistance, ensuring that the internal polybenzimidazole and phosphoric acid crosslinking is not corroded by phosphoric acid, thereby achieving high H2 permeation flux. Finally, the metal foamed titanium of this invention, after being loaded with a Pt catalyst, further improves the hydrogen permeation flux. Attached Figure Description

[0017] Figure 1 These are scanning electron microscope (SEM) images of the surfaces of pure titanium foam, titanium foam filled with polybenzimidazole, and titanium foam hybrid film filled with polybenzimidazole and phosphoric acid crosslinked. Among them, (a)-(c) are SEM images of pure titanium foam at 200 μm, 100 μm and 30 μm, respectively; (d)-(f) are SEM images of titanium foam filled with polybenzimidazole at 200 μm, 100 μm and 30 μm, respectively; and (g)-(i) are SEM images of titanium foam hybrid film filled with polybenzimidazole and phosphoric acid crosslinked at 200 μm, 100 μm and 30 μm, respectively. Figure 2 This is a schematic diagram of the principle of H2 separation using a hybrid hydrogen separation membrane with a titanium foam framework filled with organic polymers. Figure 3 This is a diagram of a device for separating H2 using a hybrid hydrogen separation membrane with a titanium foam framework filled with organic polymers. Detailed Implementation

[0018] To make the objectives and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are only for explaining the invention and are not intended to limit the invention.

[0019] Unless otherwise specified, the instruments, reagents, and materials used in the following embodiments are all conventional instruments, reagents, and materials already available in the prior art and can be obtained through legitimate commercial channels. Unless otherwise specified, the experimental methods and detection methods used in the following embodiments are all conventional experimental methods and detection methods already available in the prior art.

[0020] Example 1 This embodiment provides a hybrid hydrogen separation membrane with a titanium foam framework filled with an organic polymer, which is prepared by the following method: S1: Cut 30% porosity and 0.6mm thickness foamed titanium into 1.5cm diameter discs; add the foamed titanium discs to a beaker containing acetone solution, place the beaker in an ultrasonic cleaner, and ultrasonically clean for 30 minutes at 50Hz; replace the acetone solution in the beaker with deionized water, and add hydrochloric acid solution to adjust the pH to 5, and ultrasonically clean for 20 minutes; change the solution in sequence to ethanol, deionized water, ethanol, deionized water, and ethanol, ultrasonically clean for 20 minutes each time, and the pretreatment of foamed titanium is completed; S2: Weigh 0.9g of oven-dried polybenzimidazole powder (OPBI), add it to a beaker containing 10mL of N,N-dimethylacetamide (DMAC) solvent, place the beaker in an oil bath and heat it to 50℃, stir at 300r / min for 12h until fully dissolved, and obtain a homogeneous polybenzimidazole solution. S3: Immerse the pretreated titanium foam in a homogeneous polybenzimidazole solution, and after vacuum drying, obtain titanium foam filled with polybenzimidazole. The specific operation is as follows: S31: Immerse the foamed titanium in a beaker containing a homogenized polybenzimidazole solution, place it in a vacuum drying oven, adjust the vacuum degree to 13.0 kPa, set the temperature to 30℃, and dry for 2 hours; S32: Transfer the foamed titanium immersed in the polybenzimidazole homogenized solution to a drying oven and heat it to 60℃ for 2 hours; S33: Remove the foamed titanium from the polybenzimidazole solution and gently wipe off any excess solution from the surface with filter paper; S34: Place the lightly wiped foamed titanium into a drying oven and heat it to 80℃ for 2 hours to dry; S35: Repeat steps S32, S33, and S34 two to three times to obtain foamed titanium filled with polybenzimidazole.

[0021] S4: Immerse the foam titanium filled with polybenzimidazole in an 85% phosphoric acid (PA) solution at room temperature for 12 hours. After immersion, remove it and place it in an oven at 80°C for 2 hours to dry. This will give you a foam titanium hybrid film (Ti-OPBI-PA) filled with polybenzimidazole and phosphoric acid crosslinking.

[0022] S5: Place the foam titanium hybrid membrane filled with polybenzimidazole and phosphoric acid crosslinked inside on the sample stage of the ion sputtering instrument. Sputtering time is 3 min, current is 20 mA, vacuum degree is 3.5 Pa. Platinum particle catalyst loading treatment is applied to both sides of the foam titanium hybrid membrane filled with polybenzimidazole and phosphoric acid crosslinked inside, so that platinum particle catalyst is loaded on both surfaces of the membrane, that is, a hybrid hydrogen separation membrane with metal foam titanium as the framework and organic polymer filled in.

[0023] The surface scanning electron microscope (SEM) images of the above-mentioned foamed titanium, foamed titanium filled with OPBI, and Ti-OPBI-PA are attached. Figure 1 .Depend on Figure 1 As can be seen, (a) to (c) are magnified views of the foamed titanium without OPBI immersion, and obvious pores can be observed. (d) to (f) are magnified views of the foamed titanium with OPBI immersion, and the internal pores have been filled with OPBI. (g) to (i) are magnified views of Ti-OPBI-PA, and it can be clearly seen that the foamed titanium is fully filled after the phosphoric acid crosslinks with OPBI.

[0024] The schematic diagram of the hybrid hydrogen separation membrane for separating H2, which uses titanium foam as a framework and is filled with organic polymer, in this embodiment is attached. Figure 2 The principle behind its hydrogen separation is as follows: A hybrid hydrogen separation membrane, with a titanium foam framework and organic polymer filling, is loaded with a Pt catalyst to dissociate hydrogen into protons and electrons. Due to the concentration difference across the membrane, protons are conducted via a hydrogen bond network formed by the crosslinking of polybenzimidazole and phosphoric acid, while electrons are conducted via metallic titanium. Finally, the protons and electrons recombine into hydrogen under the action of the Pt catalyst on the membrane purge side, thus achieving hydrogen separation.

[0025] Experimental Example 1 A diagram of an apparatus for separating H2 using a hybrid hydrogen separation membrane with a titanium foam framework and filled with organic polymers is attached. Figure 3 The device consists of a self-made testing apparatus, a gas chromatograph, a horizontal tube furnace, a gas supply line, a hydrogen separation membrane, a mass flow meter, and a tail gas treatment system.

[0026] The homemade testing device consists of four vent pipes, two annular platforms (including a lower annular platform and an upper annular platform), a circular base, two symmetrically grooved pressure plates (including a lower pressure plate and an upper pressure plate, with screws installed on the surface of the pressure plates for fixing), a fixing disc, and two springs. Two vent pipes are symmetrically arranged at the center of the circular base. The lower annular platform is installed at the center and is used to place the hydrogen separation membrane. Above the lower annular platform is the upper annular platform, which has two more vent pipes. The four vent pipes pass through the two pressure plates. The lower pressure plate is pressed against the fixing disc (only penetrated by the two inner vent pipes) and then secured by tightening the two screws in the middle.

[0027] During testing, lift the lower pressure plate and place the hydrogen separation membrane on the lower annular platform. Press the lower pressure plate down until it is pressed against the fixing disc, ensuring the upper and lower annular platforms are in contact and thus compressing the hydrogen separation membrane. Tighten the screws to secure the lower pressure plate. Next, install springs in the two grooves of the lower pressure plate. Align the grooves of the upper pressure plate with the springs and press them down to half their original length. Tighten the two outer screws to secure the upper pressure plate. After securing, use sealant to achieve a tight seal.

[0028] In use, the testing device is placed in a horizontal tube furnace. Two vent pipes on the circular base are connected to the feed vent pipe on one side and the exhaust vent pipe on the other. Two vent pipes on the upper annular platform are connected to the purge gas on one side and the gas chromatograph on the other. After the gas is introduced, the H2 and N2 gases from the feed sample come into contact with the membrane. The hydrogen gas passes through the membrane for separation and is then blown into the gas chromatograph by the purge gas for detection. The gas that does not pass through the membrane for separation is discharged as waste gas.

[0029] The hydrogen separation membrane prepared in Example 1 was placed in a self-made test apparatus and sealed with sealing grease to completely enclose the membrane within the reactor. The test apparatus was placed in a horizontal tube furnace without heating (room temperature). In this experiment, nitrogen was used as the mixed gas, and 50% H2-50% N2 was introduced into the feed gas of the membrane. Inert argon was used as the purge gas in the purge gas. The purge gas tail gas was connected to a gas chromatograph for detection and analysis. The flow rates of H2 and N2 were 25 mL / min. -1 Ar flow rate is 50 mL / min -1 The flow rate of each gas is controlled by a mass flow meter.

[0030] Experiment Example 2 Using the hybrid hydrogen separation membrane with a foamed titanium framework and filled with organic polymer prepared in Example 1, the reaction temperature was controlled in a horizontal tube furnace and raised to 200°C. Under the same conditions as in Example 1, the hydrogen separation membrane was tested for its H2 permeability separation performance.

[0031] Experimental Example 3 Using the hybrid hydrogen separation membrane with a titanium foam framework filled with organic polymer prepared in Example 1, the reaction temperature was controlled in a horizontal tube furnace and raised to 250°C. Under the same conditions as in Example 1, the hydrogen separation membrane was tested for its H2 permeation separation performance.

[0032] Experiment Example 4 Using the hybrid hydrogen separation membrane with a foamed titanium framework and filled with organic polymer prepared in Example 1, the reaction temperature was controlled in a horizontal tube furnace and raised to 260°C. Under the same conditions as in Experiment 1, the hydrogen separation membrane was tested for H2 permeation separation performance.

[0033] Experimental Example 5 Using the hybrid hydrogen separation membrane with a titanium foam framework filled with organic polymer prepared in Example 1, the reaction temperature was controlled in a horizontal tube furnace and raised to 280°C. Under the same conditions as in Example 1, the hydrogen separation membrane was tested for its H2 permeability separation performance.

[0034] Table 1 H2 permeation flux of Experiments 1-5

[0035] The hybrid hydrogen separation membrane with a titanium foam framework and filled with organic polymers, prepared in this embodiment, was applied to the separation of high-purity hydrogen. Table 1 shows the results from Experiment 1, indicating that no hydrogen passed through the hybrid hydrogen separation membrane with a titanium foam framework and filled with organic polymers at room temperature. This demonstrates that the polybenzimidazole was fully incorporated into the pores of the titanium foam, and also proves that the hydrogen separation conforms to the principle mentioned in Example 1. At 200°C, the hydrogen separation membrane exhibited good hydrogen permeation flux, indicating that protons can be hopping and conducted through the hydrogen bond network of polybenzimidazole and phosphate crosslinked within the titanium foam, while electrons can be conducted through metallic titanium. Table 1 shows that the hydrogen permeation flux increases with increasing temperature, indicating that hydrogen conduction is a thermally activated process. In summary, the hybrid hydrogen separation membrane with a titanium foam framework and filled with organic polymers exhibits high hydrogen permeation flux.

[0036] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing a hybrid hydrogen separation membrane with a titanium foam framework filled with an organic polymer, characterized in that: Specifically, it includes the following steps: S1: Pretreatment of titanium foam material; S2: Dissolve the dried polybenzimidazole powder by heating and stirring with N,N-dimethylacetamide to obtain a homogeneous polybenzimidazole solution as a filler material; S3: The pretreated titanium foam is immersed in a homogeneous polybenzimidazole solution and dried under vacuum to obtain titanium foam filled with polybenzimidazole. S4: Immerse the foamed titanium filled with polybenzimidazole in a phosphoric acid solution at room temperature for a period of time and then dry it to obtain a foamed titanium hybrid film filled with polybenzimidazole and phosphoric acid crosslinked. S5: Pt particle catalysts are loaded on both sides of a foam titanium hybrid membrane filled with crosslinked polybenzimidazole and phosphoric acid by ion sputtering, thus forming a hybrid hydrogen separation membrane with metal foam titanium as the framework and organic polymers as the filling.

2. The preparation method according to claim 1, characterized in that: In step S1, the pretreatment is as follows: cut the foamed titanium into round pieces, place them in acetone, add hydrochloric acid in a deionized water solution, and ethanol for ultrasonic cleaning, and then dry them to complete the pretreatment.

3. The preparation method according to claim 2, characterized in that: The pretreatment specifically involves cutting 0.6 mm thick titanium foam into 1.5 cm diameter discs, first immersing them in acetone solution for ultrasonic cleaning for 30 min, then immersing them in a deionized water solution with added hydrochloric acid at pH 5 for ultrasonic cleaning for 20 min, and finally immersing them in alternating ultrasonic cleaning solutions of ethanol, deionized water, ethanol, deionized water, and ethanol, each for 20 min, and drying to complete the pretreatment; the ultrasonic power is 50 Hz.

4. The preparation method according to claim 1, characterized in that: In step S2, the ratio of N,N-dimethylacetamide to polybenzimidazole powder is 10 mL: 0.9 g; the temperature for heating and stirring is 50 °C, the stirring speed is 300 r / min, and the stirring time is 12 h.

5. The preparation method according to claim 1, characterized in that: In step S3, step S3 specifically includes: S31: Immerse the pretreated titanium foam material in a homogeneous polybenzimidazole solution and vacuum dry it for a period of time; S32: Transfer the foamed titanium to a drying oven and heat it to dry; S33: Remove the foamed titanium and gently wipe the surface with filter paper to remove excess solution; S34: Place the lightly wiped foam titanium into a drying oven and heat it to dry; S35: Repeat steps S32-S34 two to three times to obtain foam titanium filled with polybenzimidazole.

6. The preparation method according to claim 5, characterized in that: In step S31, the vacuum degree is 13.0 kPa, and the vacuum drying is carried out at 30°C for 2 hours; in step S32, the temperature drying is carried out at 60°C for 2 hours; in step S34, the temperature drying is carried out at 80°C for 2 hours.

7. The preparation method according to claim 1, characterized in that: Step S4 specifically involves immersing a foam titanium filled with polybenzimidazole in an 85% phosphoric acid solution at room temperature for 12 hours. After immersion, the foam titanium is removed and placed in an oven at 80°C for 2 hours to dry, thereby obtaining a foam titanium hybrid film filled with polybenzimidazole and phosphoric acid crosslinked together.

8. The preparation method according to claim 1, characterized in that: Step S5 specifically involves placing a foamed titanium hybrid membrane filled with crosslinked polybenzimidazole and phosphoric acid on the operating table of an ion sputtering instrument and performing a platinum sputtering operation to load Pt catalysts on both surfaces of the membrane, thus creating a hybrid hydrogen separation membrane with metal foamed titanium as the framework and filled with organic polymers.

9. A hybrid hydrogen separation membrane with a titanium foam framework filled with organic polymer, prepared by any one of the preparation methods described in claims 1-8.

10. The application of the hybrid hydrogen separation membrane with a titanium foam framework filled with organic polymer as described in claim 9, characterized in that: The hybrid hydrogen separation membrane is used for H2 separation.

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