A hydrogen barrier coating for hydrogen storage and transportation and its preparation method

Abstract

This invention belongs to the field of coating materials technology. This invention provides a hydrogen barrier coating for hydrogen storage and transportation and its preparation method. The preparation method includes the following steps: S1, adding 5g of nanocomposite matrix material to 400-500mL of ethanol solution, ultrasonicating, and stirring to obtain a nanocomposite matrix solution; S2, grinding 4-5g of metal-organic framework and adding it to the nanocomposite matrix solution obtained in S1, continuing stirring to obtain a dispersion solution; S3, dissolving 7.5-10g of binder and 0.5g of nano-titanium dioxide in 150-200mL of dichloromethane, stirring evenly, and adding it to the dispersion solution obtained in S2, accelerating stirring to obtain a coating precursor solution; S4, after pretreatment of steel, depositing an initial carbon source coating, then spraying the coating precursor solution obtained in S3, drying, and heat treating to obtain the final product. This invention can effectively inhibit hydrogen permeation, reduce the risk of hydrogen embrittlement, and significantly improve the hydrogen barrier performance and durability of the coating.

Description

Technical Field

[0001] This invention belongs to the field of coating materials technology, specifically relating to a hydrogen barrier coating for hydrogen storage and transportation and its preparation method. Background Technology

[0002] In the field of hydrogen storage and transportation, hydrogen embrittlement caused by hydrogen atom permeation seriously affects the service life and safety of equipment and pipelines. Currently, traditional hydrogen barrier coatings mainly use single physical barrier materials, such as metal plating and ceramic coatings.

[0003] However, these coatings have many limitations. For example, metal coatings are prone to corrosion, and ceramic coatings are brittle and prone to cracking during use, allowing hydrogen atoms to still penetrate the coating and failing to effectively suppress the risk of hydrogen embrittlement.

[0004] Therefore, there is an urgent need to develop a novel hydrogen barrier coating technology to meet the protection requirements of equipment and pipelines in the field of hydrogen storage and transportation. Summary of the Invention

[0005] To address the problems existing in the background art, the present invention provides a hydrogen barrier coating for hydrogen storage and transportation and its preparation method, which can effectively inhibit hydrogen permeation, reduce the risk of hydrogen embrittlement, and significantly improve the hydrogen barrier performance and durability of the coating.

[0006] To achieve the above objectives, in a first aspect, the present invention provides a method for preparing a hydrogen barrier coating for hydrogen storage and transportation, comprising the following steps: S1. Add 5g of nanocomposite matrix material to 400-500mL of ethanol solution, sonicate, and stir to obtain nanocomposite matrix solution; S2. Grind 4-5g of metal-organic framework and add it to the nanocomposite matrix solution obtained in S1. Continue stirring to obtain a dispersion solution. S3. Dissolve 7.5-10g of binder and 0.5g of nano titanium dioxide in 150-200mL of dichloromethane, stir evenly, and then add it to the dispersion solution obtained in S2. Accelerate stirring to obtain the coating precursor solution. S4. After pretreatment, the steel is coated with an initial carbon source coating, then sprayed with the coating precursor solution obtained in S3, dried, and heat-treated to obtain the hydrogen barrier coating used in the field of hydrogen storage and transportation.

[0007] Furthermore, in S1, the nanocomposite matrix material includes boron nitride nanotubes (BNNTs) and graphene oxide (GO).

[0008] Furthermore, the mass ratio of boron nitride nanotubes (BNNTs) to graphene oxide (GO) is 3:2.

[0009] Furthermore, in S1, the stirring speed is 300 r / min and the stirring time is 1 h.

[0010] Furthermore, in S2, the metal-organic framework is HKUST-1.

[0011] Furthermore, in S2, it is ground to 50-100nm.

[0012] Furthermore, in S3, the adhesive is polytetrafluoroethylene.

[0013] Furthermore, in S3, the accelerated stirring speed is 500 r / min, and the accelerated stirring time is 3 h.

[0014] Furthermore, in S4, the heat treatment temperature is 150-180℃, and the heat treatment time is 2.5-3h.

[0015] Secondly, the present invention provides a hydrogen barrier coating for hydrogen storage and transportation, which is prepared by the above-described preparation method.

[0016] This application has the following beneficial effects: In this invention, the nanocomposite matrix material is composed of boron nitride nanotubes (BNNTs) and graphene oxide (GO). Boron nitride nanotubes possess excellent chemical stability and mechanical strength, and their unique hollow structure acts as a physical barrier to hydrogen atom diffusion. Graphene oxide has a large specific surface area and good film-forming properties. The two are combined at a mass ratio of 3:2 to form a three-dimensional network structure with gradient pores, controlling the coating porosity to 5%-10% and the pore size distribution to 1-10 nanometers. This significantly increases the diffusion path of hydrogen atoms within the coating and slows down the hydrogen atom penetration rate. (Smart Response Material) The metal-organic framework (MOF) material is HKUST-1 (copper-based MOF). HKUST-1 possesses abundant metal sites and an ultra-large specific surface area. During diffusion, hydrogen atoms undergo a reversible adsorption reaction with the metal sites in the MOF material, temporarily immobilizing themselves within the MOF's porous structure. When the hydrogen concentration outside the coating decreases, hydrogen atoms desorb, achieving dynamic control over hydrogen atoms, while simultaneously enhancing the coating's flexibility and reducing the risk of hydrogen embrittlement cracking. Using polytetrafluoroethylene (PTFE) as a binder, its excellent chemical stability and corrosion resistance can firmly bond the nanocomposite matrix material with the smart responsive material, forming a continuous and dense coating. Nano-titanium dioxide (TiO2) is used as an additive to fill the micropores of the coating, improving its density. Furthermore, the photocatalytic properties of TiO2 can promote the adsorption and desorption reactions of hydrogen atoms in MOF materials under specific light irradiation, enhancing their hydrogen barrier properties.

[0017] The hydrogen-barrier coating of this invention utilizes a synergistic effect of a "nanoscale composite structure + smart responsive material (metal-organic framework)," which reduces hydrogen permeability by more than 80% compared to traditional coatings, significantly improving the hydrogen barrier effect. The smart responsive material enables dynamic control of hydrogen atoms, effectively reducing the risk of hydrogen embrittlement and extending the service life of equipment and pipelines. The coating exhibits good flexibility and weather resistance, adapting to the hydrogen storage and transportation needs under different temperature, pressure, and environmental conditions. The preparation process and materials are highly feasible in existing industrial production, facilitating large-scale production and application. Detailed Implementation

[0018] The present application will be further described in detail below with reference to the embodiments.

[0019] Unless otherwise specified, the raw materials used in the embodiments and comparative examples of this application are all commercially available.

[0020] Example 1 1.1 Material Preparation L415Q pipeline steel, commonly used in domestic hydrogen transportation, was selected as the base material. A 1m long section of pipe with a diameter of 406mm was cut. The L415Q pipeline steel was first coarsely ground and then finely ground with sandpaper. It was then ultrasonically cleaned with acetone for 15 minutes to remove surface oil and impurities. After rinsing with deionized water, it was dried in a 100℃ drying oven for 2 hours. Take 3g of boron nitride nanotubes and 2g of graphene oxide and add them to 500mL of ethanol solution. Disperse them in an ultrasonic cleaner for 30 minutes to ensure uniform dispersion. Place 5g of HKUST-1 into a grinder and grind it until the particle size reaches 50-100 nanometers.

[0021] Weigh 10g of polytetrafluoroethylene and 0.5g of nano titanium dioxide, dissolve them in 200mL of dichloromethane, and stir until a solution is formed. 1.2 Preparation of coating precursor solution The dispersed boron nitride nanotubes and graphene oxide solution were poured into a stirring container and stirred at 300 r / min for 1 hour to obtain a nanocomposite matrix solution. Add the ground HKUST-1 to the nanocomposite matrix solution and continue stirring for 2 hours to ensure that HKUST-1 is uniformly dispersed in the solution. A mixed solution of polytetrafluoroethylene and nano-titanium dioxide was slowly added, and the stirring speed was increased to 500 r / min. The mixture was stirred for 3 hours to obtain a uniform coating precursor solution. 1.3 Coating Application and Post-treatment The treated L415Q pipeline steel was placed in a chemical vapor deposition (CVD) apparatus and deposited with an initial coating 0.5 micrometers thick using methane as the carbon source at 700°C under an argon protective atmosphere. Using a high-pressure airless spraying device, the coating precursor solution is sprayed onto the pipe surface at a pressure of 0.3 MPa, and the coating thickness is controlled to be 150 micrometers. The coated pipes are placed in a vacuum drying oven and heat-treated at 180°C for 2.5 hours to cure and densify the coating. Example 2 2.1 Material Preparation The base material was selected from Q345R steel plates commonly used in domestic hydrogen storage containers, which were cut into plates with dimensions of 500mm×500mm×10mm. First, the surface of the steel plates was sandblasted to remove oxide scale and impurities, then wiped with acetone to remove oil stains, and finally rinsed with deionized water and allowed to air dry. Weigh 3g of boron nitride nanotubes and 2g of graphene oxide, add them to 400mL of ethanol solution, and ultrasonically disperse for 30 minutes. Grind 4g of HKUST-1 to a particle size of 50-100 nanometers. Measure 7.5g of polytetrafluoroethylene and 0.5g of nano-titanium dioxide and dissolve them in 150mL of dichloromethane.

[0022] 2.2 Preparation of coating precursor solution First, stir the mixed solution of boron nitride nanotubes and graphene oxide for 1 hour to form a nanocomposite matrix solution. Add the ground HKUST-1 and stir for 2 hours, then add the mixed solution of polytetrafluoroethylene and nano titanium dioxide and stir for 3 hours to obtain the coating precursor solution. 2.3 Coating Application and Post-treatment The treated Q345R steel plate was placed in a chemical vapor deposition apparatus and a 0.5-micron initial coating was deposited at 700°C under argon protection. Using a high-pressure airless spraying device, the coating precursor solution is sprayed onto the steel plate surface at a pressure of 0.3 MPa, with the thickness controlled at 200 micrometers. The coated steel plate was placed in a vacuum environment and heat-treated at 150°C for 3 hours to complete the coating preparation. Test case 3.1 Hydrogen permeability test The test used the electrochemical hydrogen permeation method (refer to ASTM G148-2017) to simulate typical hydrogen storage and transportation conditions (temperature 30℃, hydrogen pressure 1MPa), monitor the steady-state permeation flux of hydrogen atoms through the coating-substrate system, and calculate the permeability.

[0023] Table 1. Hydrogen permeability test results 3.2 Hydrogen embrittlement suppression effect test Slow strain rate tensile test (SSRT) (refer to GB / T15970.6-2007) was used to tensile the sample in a hydrogen environment (1 MPa, 30℃), and the fracture morphology was observed by scanning electron microscopy (SEM) to assess the risk of hydrogen embrittlement.

[0024] The test results (data) are shown in Table 2.

[0025] Table 2. Test results of hydrogen embrittlement suppression effect 3.3 Corrosion Resistance Test Test standard: GB / T10125-2021 "Artificial Atmosphere Corrosion Test - Salt Spray Test"; Test conditions: 5% NaCl solution, temperature 35℃, salt spray deposition rate 1-2 mL / (h) (dm²), lasting 500 hours.

[0026] The test results (data) are shown in Table 3.

[0027] Table 3. Corrosion resistance test results 3.4 Thermal cycling resistance test Test standard: GB / T2423.22-2012 Environmental testing - Part 2: Test methods Test N: Temperature change; Test conditions: Temperature cycling range -40℃ (low temperature held for 2 hours) → 80℃ (high temperature held for 2 hours), 50 cycles, heating / cooling rate of 5℃ / min per cycle.

[0028] The test results are shown in Table 4.

[0029] Table 4. Results of thermal cycling resistance test 3.5 Mechanical property testing Test items: flexibility and Vickers hardness.

[0030] The test results are shown in Table 5.

[0031] Table 5. Mechanical property test results It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.

[0032] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.

Claims

1. A method for preparing a hydrogen-barrier coating for hydrogen storage and transportation, characterized in that, Includes the following steps: S1. Add 5g of nanocomposite matrix material to 400-500mL of ethanol solution, sonicate, and stir to obtain nanocomposite matrix solution; S2. Grind 4-5g of metal-organic framework and add it to the nanocomposite matrix solution obtained in S1. Continue stirring to obtain a dispersion solution. S3. Dissolve 7.5-10g of binder and 0.5g of nano titanium dioxide in 150-200mL of dichloromethane, stir evenly, and then add it to the dispersion solution obtained in S2. Accelerate stirring to obtain the coating precursor solution. S4. After pretreatment, the steel is coated with an initial carbon source coating, then sprayed with the coating precursor solution obtained in S3, dried, and heat-treated to obtain the hydrogen barrier coating used in the field of hydrogen storage and transportation.

2. The method for preparing a hydrogen-barrier coating for hydrogen storage and transportation according to claim 1, characterized in that, In S1, the nanocomposite matrix material includes boron nitride nanotubes and graphene oxide.

3. The method for preparing a hydrogen-barrier coating for hydrogen storage and transportation according to claim 2, characterized in that, The mass ratio of boron nitride nanotubes to graphene oxide is 3:

2.

4. The method for preparing a hydrogen-barrier coating for hydrogen storage and transportation according to claim 1, characterized in that, In S1, the stirring speed is 300 r / min and the stirring time is 1 h.

5. The method for preparing a hydrogen-barrier coating for hydrogen storage and transportation according to claim 1, characterized in that, In S2, the metal-organic framework is HKUST-1.

6. The method for preparing a hydrogen-barrier coating for hydrogen storage and transportation according to claim 1 or 5, characterized in that, In S2, grind to 50-100nm.

7. The method for preparing a hydrogen-barrier coating for hydrogen storage and transportation according to claim 1, characterized in that, In S3, the adhesive is polytetrafluoroethylene.

8. The method for preparing a hydrogen-barrier coating for hydrogen storage and transportation according to claim 1, characterized in that, In S3, the accelerated stirring speed is 500 r / min, and the accelerated stirring time is 3 h.

9. The method for preparing a hydrogen-barrier coating for hydrogen storage and transportation according to claim 1, characterized in that, In S4, the heat treatment temperature is 150-180℃ and the heat treatment time is 2.5-3h.

10. A hydrogen-barrier coating for use in hydrogen storage and transportation, characterized in that, It is prepared by the preparation method described in any one of claims 1-9.

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