Preparation method of high-temperature chlorine salt corrosion resistant high-entropy glass ceramic based on industrial solid waste

Abstract

The invention relates to a method for preparing high-entropy glass ceramic resistant to high-temperature chlorine salt corrosion based on industrial waste. According to the method, industrial waste, an additive, a transition metal oxide and a rare earth oxide are utilized, and the high-entropy glass ceramic is prepared through melt pouring. The obtained high-entropy glass ceramic has excellent molten chlorine salt corrosion resistance at high temperature, the glass ceramic can effectively recycle industrial waste, save resources and alleviate environmental pollution, no special process exists in the processing process, the preparation method is simple and convenient, and industrial production can be further realized.

Description

Technical Field

[0001] The present invention relates to the technical field of high-temperature molten salt corrosion-resistant heat storage materials, and specifically relates to a preparation method of a corrosion-resistant high-entropy glass-ceramic based on industrial solid waste and applicable to high-temperature chloride salts. Background Art

[0002] With the large-scale application of the third-generation concentrated solar power (CSP) technology, the molten chloride salt heat storage system has become the mainstream choice due to its excellent thermal stability and economy. However, its strong corrosiveness to metal components in high-temperature service environments severely restricts the safe operation and lifespan of equipment. Although certain progress has been made in existing coating protection and molten salt purification technologies, the high costs and limited performance improvement space urgently require innovative breakthroughs in the materials field.

[0003] The resource utilization of industrial solid waste has opened up a new path for the research and development of corrosion protection materials. Steel slag generated from steel smelting is rich in calcium, silicon, and iron oxides. Long-term accumulation not only occupies land resources but also causes environmental pollution. Research shows that preparing glass-ceramics using industrial solid waste such as steel slag can not only significantly reduce material costs but also achieve the dual benefits of resource recycling and environmental protection. However, the initial steel slag-based materials have defects such as insufficient densification and weak chloride ion penetration resistance, making it difficult to meet the stringent requirements of the high-temperature chloride salt environment in solar thermal power generation systems. There is an urgent need to optimize their service performance through material design.

[0004] The high-entropy material system provides a theoretical support for breaking through the performance bottleneck of traditional materials. Different from single-principal-element materials, high-entropy ceramics form a unique lattice distortion effect through the design of equimolar ratios of multiple elements, significantly improving high-temperature stability and corrosion resistance. For example, studies such as TU et al. found that high-entropy rare earth zirconate ceramics exhibit excellent resistance to CMAS corrosion at 1300 °C, significantly exceeding traditional single-element rare earth ceramics; Wang et al. successfully prepared dense composite ceramics with extremely high CMAS corrosion resistance by compounding high-entropy glass phases. However, current high-entropy ceramics rely on high-purity raw materials, resulting in high preparation costs and limiting their engineering applications.

[0005] To address the above problems, this patent innovatively integrates the design of high-entropy materials and the concept of industrial solid waste resource utilization. Using industrial solid waste such as steel slag as the matrix raw material, the element ratio and microstructure are regulated by adding transition metal oxides or rare earth oxides to construct a multiphase symbiotic high-entropy glass-ceramic system. This material effectively blocks the chloride ion diffusion channels through the lattice distortion effect, synchronously optimizing densification and thermal stability, providing an innovative solution that combines economy, environmental protection, and reliability for the high-temperature chloride salt corrosion protection of key equipment in fields such as solar thermal power generation and thermochemical energy storage, and promoting the transformation of high-temperature protection technology to an active design paradigm. Summary of the Invention

[0006] The purpose of the present invention is to provide a high-entropy glass-ceramic resistant to high-temperature chloride corrosion prepared from industrial solid waste, to provide a new direction for the recycling and reuse of industrial waste, and to promote resource conservation and environmental pollution prevention and control.

[0007] The present invention provides a method for preparing high-entropy glass ceramics based on industrial solid waste and resistant to high-temperature chloride corrosion, comprising the following steps:

[0008] S1, using a crushing device to crush the blocky industrial solid waste, using a screening device to screen the crushed waste, and continuing to crush the remaining larger particle size powder after screening, and repeatedly screening to obtain a sample powder that meets the particle size requirements;

[0009] S2, adding additives, transition metal oxides and rare earth oxides to the industrial solid waste sample powder obtained in S1 and drying them;

[0010] S3, mixing and grinding the dried sample powder obtained in S2, the additive, the transition metal oxide and the rare earth oxide according to mass percentage until they are uniform to obtain a mixed powder;

[0011] S4, placing the mixed powder obtained in S3 into a muffle furnace for heating and melting to form a molten liquid, and keeping the mixture warm in a molten state;

[0012] S5, pouring the molten liquid obtained in S4 into a mold for pressing and forming, placing the formed sample in a muffle furnace for annealing, and keeping the sample in the muffle furnace for nucleation and crystallization after annealing to obtain a final sample.

[0013] The particle size of the sample powder in S1 is required to be ≤200 mesh.

[0014] The drying temperature in S2 is 100° C.-150° C., and the drying time is 24 h-48 h.

[0015] The heating rate in S4 is 5°C / min-10°C / min, the insulation temperature is 1400°C-1600°C, and the insulation time is 1h-3h.

[0016] The annealing temperature in S5 is 500°C-700°C, the annealing time is 1h-5h, the insulation nucleation temperature is 600°C-800°C, the nucleation time is 1h-6h, the crystallization temperature is 800°C-1000°C, and the crystallization time is 5h-24h.

[0017] The industrial solid waste is one or more of steel slag, coal gangue, and fly ash;

[0018] The additives include Al2O3, SiO2 and one or more other substances capable of forming glass;

[0019] The transition metal oxides include Cr2O3, TiO2 and one or more substances that can improve the hardness and corrosion resistance of the material;

[0020] The rare earth oxides include Lu2O3 and one or more substances that can improve the high-temperature resistance and refine the grains.

[0021] The mass percentages in S3 are as follows: the industrial solid waste sample powder accounts for 40%-80%, and the additive accounts for 5%-20%. The transition metal oxides and rare earth oxides can be used both or only one of them, and they together account for 5%-40%.

[0022] The high-entropy glass-ceramic resistant to high-temperature chloride salt corrosion of the present invention has the following advantages:

[0023] 1. The high-entropy glass-ceramic resistant to high-temperature chloride salt corrosion is prepared from industrial waste, providing a new direction for the recycling of industrial waste, solving the environmental pollution problem caused by the accumulation of industrial waste, and reducing the cost of preparing anti-corrosion materials.

[0024] 2. The corrosion resistance of the high-entropy glass-ceramic in the high-temperature chloride salt molten salt environment at 800°C is far better than that of ordinary glass-ceramics and alloys, and the service life is greatly increased.

[0025] 3. The related preparation process is simple and has no special requirements, which is conducive to the industrial application of the coating. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a flow chart of the preparation method of the high-entropy glass-ceramic resistant to high-temperature chloride salt corrosion prepared by the present invention based on industrial solid waste. DETAILED DESCRIPTION OF THE INVENTION

[0027] The following further describes the present invention in detail in conjunction with the embodiments and the attached Figure 1 drawings.

[0028] Example 1

[0029] Through the following steps, a high-entropy glass-ceramic resistant to high-temperature chloride salt corrosion and its preparation method are prepared from industrial solid waste:

[0030] (1) Use a crusher to crush the steel slag. The crushing time is 150 s. Screen the crushed steel slag to obtain steel slag powder with a particle size ≤ 200 mesh. The remaining large-particle steel slag continues to be crushed and screened until powder with a particle size ≤ 200 mesh is obtained. Then put the powder into a drying oven and dry it at 110°C for 24 h;

[0031] (2) Dry the steel slag, A1203, Si02, Cr203, Ti02, Lu203, etc.

[0032] (3) Mix and grind the above-mentioned dried substances by mass percentage until uniform to obtain a mixed powder.

[0033] (4) Put the mixed powder into a muffle furnace. The furnace is heated to 1400 °C at a rate of 10 °C / min, and the powder is kept at the molten state for 2 h.

[0034] (5) Pour the molten liquid into a mold and press it into shape. Put the formed sample into a muffle furnace. The sample is annealed at 600 °C for 3 h, kept for nucleation at 710 °C for 4 h, and kept for crystallization at 920 °C for 10 h to obtain a high-entropy glass ceramic resistant to chloride salt corrosion.

[0035] Example 2

[0036] A high-entropy glass ceramic resistant to high-temperature chloride salt corrosion and its preparation method were prepared from industrial solid waste through the following steps:

[0037] (1) Use a crusher to crush the steel slag for 150 s. Screen the crushed steel slag to obtain steel slag powder with a particle size ≤ 200 mesh. The remaining large-particle steel slag is continuously crushed and screened until powder with a particle size ≤ 200 mesh is obtained. Then put the powder into a drying oven and dry it at 110 °C for 24 h.

[0038] (2) Dry the steel slag, A12O3, SiO2, NiO, MoO2, Nb2O5, etc.

[0039] (3) Mix and grind the above-mentioned dried substances by mass percentage until uniform to obtain a mixed powder.

[0040] (4) Put the mixed powder into a muffle furnace. The furnace is heated to 1400 °C at a rate of 10 °C / min, and the powder is kept at the molten state for 2 h.

[0041] (5) Pour the molten liquid into a mold and press it into shape. Put the formed sample into a muffle furnace. The sample is annealed at 600 °C for 3 h, kept for nucleation at 710 °C for 4 h, and kept for crystallization at 920 °C for 10 h to obtain a high-entropy glass ceramic resistant to chloride salt corrosion.

[0042] Test:

[0043] Test the performance of the high-entropy glass ceramic. Immerse the high-entropy glass ceramic in a high-temperature NaCl-KCl molten salt at 800 °C, take it out after 35 days, and at the same time immerse 347H (high-alloy austenitic stainless steel) and ordinary glass ceramic for testing under the same conditions. Observe the surface conditions of the samples for comparison, and the results are shown in the table.

[0044]

[0045] As shown in the above table, the high-entropy glass-ceramics prepared in the present invention have excellent resistance to molten chloride corrosion.

[0046] The above embodiments are only used to illustrate the present invention and are not intended to limit the present invention. Those of ordinary skill in the relevant technical field can also make various changes and modifications without departing from the essence and scope of the present invention. Therefore, all equivalent technical solutions also fall within the protection scope of the present invention.

[0047] The content not detailed in this specification belongs to the well-known prior art of those skilled in the art.

Claims

1. A preparation method of a high-temperature-resistant chloride salt-corrosion-resistant high-entropy glass-ceramic based on industrial solid waste, characterized in that, It includes the following steps: S1. Use a crushing device to crush the bulk industrial solid waste, and use a screening device to screen the crushed waste. The larger particle size powder remaining after screening is continuously crushed, and screening is repeated to obtain sample powder that meets the particle size requirements. S2. Add additives, transition metal oxides, and rare earth oxides to the industrial solid waste sample powder obtained in S1 and dry it. S3. Mix and grind the dried sample powder, additives, transition metal oxides, and rare earth oxides obtained in S2 according to mass percentages until uniform to obtain a mixed powder. S4. Put the mixed powder obtained in S3 into a muffle furnace for heating and melting to form a molten liquid, and keep it at the molten state for heat preservation. S5. Pour the molten liquid obtained in S4 into a mold for pressing and forming, put the formed sample into a muffle furnace for annealing, and keep the sample in the muffle furnace for nucleation and crystallization after annealing to obtain the final sample.

2. The preparation method according to claim 1, characterized in that: The particle size requirement of the sample powder in S1 is ≤200 mesh.

3. The preparation method according to claim 1, characterized in that: The drying temperature in S2 is 100°C - 150°C, and the drying time is 24h - 48h.

4. The preparation method according to claim 1, wherein: The heating rate in S4 is 5°C / min - 10°C / min, the heat preservation temperature is 1400°C - 1600°C, and the heat preservation time is 1h - 3h.

5. The preparation method according to claim 1, characterized in that: The annealing temperature in S5 is 500°C - 700°C, the annealing time is 1h - 5h, the nucleation temperature for heat preservation is 600°C - 800°C, the nucleation time is 1h - 6h, the crystallization temperature is 800°C - 1000°C, and the crystallization time is 5h - 24h.

6. The preparation method according to claim 1, wherein: The industrial solid waste is one or more of steel slag, coal gangue, and fly ash; The additives include Al2O3, SiO2, and one or more substances that can play a role in forming glass; The transition metal oxides include Cr2O3, TiO2, and one or more substances that can play a role in improving the hardness and corrosion resistance of materials; The rare earth oxides include Lu2O3 and one or more substances that can play a role in improving high-temperature resistance and refining grains.

7. The preparation method according to claim 1, characterized in that: The mass percentages in S3 are as follows: the proportion of the industrial solid waste sample powder is 40% - 80%, the proportion of the additives is 5% - 20%, and the total proportion of the transition metal oxides and rare earth oxides is 5% - 40%.

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