A high-temperature resistant filter material capable of removing harmful gases, its preparation method and application

Abstract

This invention provides a high-temperature resistant filter material capable of removing harmful gases, its preparation method, and its application, relating to the field of high-temperature filter material technology. The high-temperature resistant filter material comprises a filter layer, an adsorption layer, a corrosion-resistant layer, a reinforcing layer, and a base fabric layer stacked sequentially; the adsorption layer is a blown-spun modified activated carbon / polyetheretherketone composite fiber membrane. This invention effectively improves the thermal and chemical stability of the filter material. While ensuring filtration efficiency, the modified activated carbon used in the adsorption layer has a strong removal capacity for harmful gases, enabling efficient filtration of high-temperature flue gas. By combining the micro-nano structure formed by the PTFE microporous membrane of the filter layer and the blown-spun fiber membrane of the adsorption layer, gradient filtration is achieved, effectively improving the filtration accuracy of the filter material. Its tensile strength is also unaffected by high-temperature environments, making it suitable for treating high-temperature flue gas.

Description

Technical Field

[0001] This invention relates to the field of high-temperature filtration materials technology, and in particular to a high-temperature resistant filtration material capable of removing harmful gases, its preparation method, and its application. Background Technology

[0002] With the accelerating pace of industrialization, environmental pollution caused by high-temperature exhaust emissions and waste combustion is increasingly attracting attention. These high-temperature flue gases typically contain harmful components such as nitrogen oxides and sulfur oxides, as well as fine particulate dust. Direct emission of these gases will inevitably cause serious air pollution and threaten public health. Therefore, the development of high-temperature filtration and dust removal technology is urgently needed. As its core component, high-temperature filter materials are particularly important. Traditional filter materials mainly target solid dust particles and cannot effectively remove toxic and harmful components. High-temperature resistant filter materials that can synergistically control both dust particles and harmful gases will be an important direction for future development. Activated carbon, with its large specific surface area, strong adsorption capacity, good thermal stability, and low price, has been widely used in the removal of odors, organic / inorganic pollutants, and flue gas desulfurization. Therefore, a high-temperature resistant filter material based on activated carbon adsorption of harmful gases is proposed. Summary of the Invention

[0003] The purpose of this invention is to provide a high-temperature resistant filter material that can remove harmful gases, its preparation method and application, so as to solve the problem that existing high-temperature resistant filter materials cannot simultaneously treat dust particles and harmful gases in waste.

[0004] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0005] This invention provides a high-temperature resistant filter material that can remove harmful gases, comprising a filter layer, an adsorption layer, a corrosion-resistant layer, a reinforcing layer, and a base fabric layer stacked sequentially.

[0006] The adsorption layer is a blown modified activated carbon / polyetheretherketone composite fiber membrane.

[0007] Preferably, the preparation method of the blown-spun modified activated carbon / polyetheretherketone composite fiber membrane includes the following steps:

[0008] 1) The activated carbon is mixed with a strong oxidant for preliminary modification. Then, the preliminarily modified activated carbon is mixed with a mixed solution containing melamine, urea and ammonia for impregnation treatment. The impregnated activated carbon is then calcined at high temperature to obtain modified activated carbon with alkaline functional groups on the surface.

[0009] 2) Mix polyetheretherketone, organic solvent and modified activated carbon to obtain modified activated carbon / polyetheretherketone spinning solution, and spin to obtain blow-spun modified activated carbon / polyetheretherketone composite fiber membrane.

[0010] Preferably, the initial modification temperature in step 1) is 25–40°C, and the initial modification time is 12–24 hours;

[0011] The mass-to-volume ratio of the preliminarily modified activated carbon to the mixed solution containing melamine, urea, and ammonia is 1 g: 1.5–2.5 mL;

[0012] The mass ratio of melamine, urea and ammonia is 2:1:1 to 2.

[0013] The concentration of the ammonia solution is 25 wt%.

[0014] The soaking time is 12–18 hours;

[0015] The high-temperature calcination temperature is 830-880℃, the high-temperature calcination time is 2-3 hours, and the high-temperature calcination atmosphere is a mixture of ammonia and nitrogen.

[0016] The volume ratio of ammonia to nitrogen is 1:1 to 1.5.

[0017] Preferably, the concentration of polyetheretherketone in the modified activated carbon / polyetheretherketone spinning solution in step 2) is 3-15 wt%.

[0018] The mass ratio of modified activated carbon to polyetheretherketone is 10-30:70-90.

[0019] Preferably, in step 2), the spinning temperature is 20-30°C, the spinning humidity is 10-20%, the spinning voltage is 15-20kV, the spinning flow rate is 0.3-1mL / h, the spinning distance is 13-20cm, and the spinning airflow velocity is 40-60m / s.

[0020] Preferably, the filter layer is prepared by mixing polytetrafluoroethylene, nonionic surfactant, foaming agent and water to obtain a foaming coating finishing liquid, foaming it and scraping the foam onto the upper surface of the adsorption layer with a scraper, and then hot-pressing a layer of polytetrafluoroethylene microporous membrane on the surface to obtain the filter layer.

[0021] The mass ratio of polytetrafluoroethylene, nonionic surfactant, foaming agent and water is 40-60:5-7:2-3:30-53.

[0022] Preferably, the corrosion-resistant layer is prepared by mixing basalt fiber, aramid fiber and glass fiber, and sequentially performing opening, carding, web laying and needle punching to obtain the corrosion-resistant layer;

[0023] The mass ratio of basalt fiber, aramid fiber and glass fiber is 1:3:2-3;

[0024] The method for preparing the reinforcing layer is to mix aramid fibers with polymer fibers and then sequentially perform opening, carding, web laying, and needle punching to obtain the reinforcing layer.

[0025] The polymer fiber is one of polyimide fiber, nylon 66 and polyetheretherketone fiber;

[0026] The mass ratio of aramid to polymer fiber is 35-50:50-65;

[0027] The base fabric layer is polytetrafluoroethylene nonwoven fabric.

[0028] Preferably, the mass ratio of the corrosion-resistant layer, the reinforcing layer, and the base fabric layer is 35-60:65-40:40-60.

[0029] The present invention also provides a method for preparing the above-mentioned filter material, comprising the following steps:

[0030] 1) The corrosion-resistant layer and the base fabric layer are stacked on the upper and lower surfaces of the reinforcing layer, respectively, and needle-punched to obtain a three-dimensional felt-like material;

[0031] 2) Using a three-dimensional felt-like material as a substrate, spinning is performed directly on the surface of the corrosion-resistant layer to obtain an adsorption layer, and a filter layer is prepared on the surface of the adsorption layer.

[0032] The basis weight of the three-dimensional felt-like material is 200–800 g / m³. 2 ;

[0033] The basis weight of the adsorption layer is 2.5–4 g / m³. 2 ;

[0034] The weight of the filter layer is 3-4 g / m³. 2 .

[0035] The present invention also provides the application of the above-mentioned filter material in the removal of harmful gases.

[0036] The present invention has at least the following beneficial effects:

[0037] 1. The high-temperature resistant filter material of the present invention is composed of a filter layer, an adsorption layer, a corrosion-resistant layer, a reinforcing layer and a base fabric layer, which effectively improves the thermal and chemical stability of the filter material. While ensuring filtration efficiency, the adsorption layer modified activated carbon enhances the removal capacity of harmful gases, thereby achieving high-efficiency filtration of high-temperature flue gas.

[0038] 2. This invention achieves gradient filtration through a micro-nano structure composite formed by a PTFE microporous membrane filter layer and a blown fiber membrane adsorption layer, effectively improving the filtration accuracy of the filter material. The PTFE filter layer has an extremely low coefficient of friction, ensuring effective filtration while preventing dust adhesion, thus facilitating easy dust removal and extending the service life of the filter media. Attached Figure Description

[0039] Figure 1 This is a structural diagram of the high-temperature resistant filter material, wherein 1-base fabric layer, 2-reinforcing layer, 3-corrosion resistant layer, 4-adsorption layer, and 5-filter layer;

[0040] Figure 2 This is a flowchart illustrating the preparation process of the high-temperature resistant filter material. Detailed Implementation

[0041] This invention provides a high-temperature resistant filter material capable of removing harmful gases, comprising a filter layer, an adsorption layer, a corrosion-resistant layer, a reinforcing layer, and a base fabric layer stacked sequentially, as shown in the schematic diagram below. Figure 1 As shown, 1-base fabric layer, 2-reinforcing layer, 3-corrosion resistant layer, 4-adsorption layer, 5-filter layer;

[0042] The adsorption layer is a blown modified activated carbon / polyetheretherketone composite fiber membrane.

[0043] In this invention, the preparation method of the blown carbon / polyether ether ketone composite fiber membrane includes the following steps:

[0044] 1) The activated carbon is mixed with a strong oxidant for preliminary modification. Then, the preliminarily modified activated carbon is mixed with a mixed solution containing melamine, urea and ammonia for impregnation treatment. The impregnated activated carbon is then calcined at high temperature to obtain modified activated carbon with alkaline functional groups on the surface.

[0045] 2) Mix polyetheretherketone, organic solvent and modified activated carbon to obtain modified activated carbon / polyetheretherketone spinning solution, and spin to obtain blow-spun modified activated carbon / polyetheretherketone composite fiber membrane.

[0046] In this invention, the spinning is airflow-assisted electrospinning.

[0047] In this invention, the initial modification temperature in step 1) is 25-40°C, preferably 28-38°C, more preferably 30-35°C, and even more preferably 32°C; the initial modification time is 12-24h, preferably 14-22h, more preferably 15-20h, and even more preferably 17-18h.

[0048] The strong oxidant is a hydrogen peroxide solution, and the concentration of the hydrogen peroxide solution is 10-40%, preferably 15-35 wt%, more preferably 20-30 wt%, and even more preferably 25 wt%.

[0049] The mass ratio of activated carbon to strong oxidant is 1:2 to 3.

[0050] In this invention, the mass-to-volume ratio of the preliminarily modified activated carbon to the mixed solution containing melamine, urea and ammonia is 1g:1.5-2.5mL, preferably 1g:1.6-2.4mL, more preferably 1g:1.7-2.3mL, even more preferably 1g:1.8-2.2mL, and even more preferably 1g:1.9-2.0mL.

[0051] In this invention, the mass ratio of melamine, urea and ammonia is 2:1:1 to 2, preferably 2:1:1.2 to 1.8, more preferably 2:1:1.4 to 1.6, and even more preferably 2:1:1.5.

[0052] In this invention, the concentration of the ammonia water is 25 wt%.

[0053] In this invention, the soaking time is 12-18 hours, preferably 13-17 hours, more preferably 14-16 hours, and even more preferably 15 hours.

[0054] In this invention, the high-temperature calcination temperature is 830-880℃, preferably 835-875℃, more preferably 840-870℃, even more preferably 845-865℃, and even more preferably 850-860℃; the high-temperature calcination time is 2-3h, preferably 2.25-2.75h, and even more preferably 2.5h.

[0055] In this invention, the atmosphere for high-temperature calcination is a mixture of ammonia and nitrogen.

[0056] In this invention, the volume ratio of ammonia to nitrogen is 1:1 to 1.5, preferably 1:1.1 to 1.4, and more preferably 1:1.2 to 1.3.

[0057] Ammonia reacts with the surface of activated carbon under a nitrogen atmosphere to generate basic functional groups, thereby modifying the activated carbon to enhance its adsorption of specific acidic harmful gases, increasing the accuracy of harmful gas adsorption, and thus improving adsorption efficiency.

[0058] In this invention, the concentration of polyether ether ketone in the modified activated carbon / polyether ether ketone spinning solution in step 2) is 3-15 wt%, preferably 5-13 wt%, more preferably 7-10 wt%, and even more preferably 8-9 wt%.

[0059] In this invention, the mass ratio of the modified activated carbon to polyetheretherketone is 10-30:70-90, preferably 15-25:75-85, more preferably 18-22:78-83, and even more preferably 20:80.

[0060] In this invention, the spinning temperature in step 2) is 20–30°C, preferably 22–28°C, more preferably 24–26°C, and even more preferably 25°C; the spinning humidity is 10–20%, preferably 12–19%, more preferably 14–18%, and even more preferably 15–17%; the spinning voltage is 15–20 kV, preferably 16–19 kV, and even more preferably 17–18 kV; the spinning flow rate is 0.3–1 mL / h, preferably 0. The flow rate is 0.4–0.9 mL / h, more preferably 0.5–0.8 mL / h, and even more preferably 0.6–0.7 mL / h; the spinning distance is 13–20 cm, preferably 14–19 cm, more preferably 15–18 cm, and even more preferably 16–17 cm; the spinning airflow velocity is 40–60 m / s, preferably 43–58 m / s, more preferably 45–55 m / s, even more preferably 48–52 m / s, and even more preferably 50 m / s.

[0061] In this invention, the filter layer is prepared by mixing polytetrafluoroethylene, nonionic surfactant, foaming agent and water to obtain a foaming coating finishing liquid, foaming it and scraping the foam onto the upper surface of the adsorption layer with a scraper, and then hot-pressing a layer of polytetrafluoroethylene microporous membrane on the surface to obtain the filter layer. The polytetrafluoroethylene microporous membrane plays the main filtration role and has the characteristics of low resistance and high efficiency, which can improve the filtration accuracy.

[0062] In this invention, the amount of foam coated onto the upper surface of the adsorption layer is 0.6–1.0 g / m³. 2 0.7~0.9g / m 2 More preferably 0.8 g / m 2 .

[0063] In this invention, the mass ratio of polytetrafluoroethylene, nonionic surfactant, foaming agent and water is 40-60:5-7:2-3:30-53, preferably 43-58:5-7:2-3:35-50, more preferably 45-55:5-7:2-3:38-45, and even more preferably 48-50:6:2:40-42.

[0064] In this invention, the basis weight of the polytetrafluoroethylene microporous membrane is 3-4 g / m³. 2 Thickness 10–15 μm, pore size 1–3 μm, air permeability 45–60 L / m 2 •s, tensile breaking strength is ≥2.5MPa in the longitudinal direction and ≥2.5MPa in the transverse direction, and elongation at break is ≥70% in the longitudinal direction and ≥70% in the transverse direction.

[0065] In this invention, the corrosion-resistant layer is prepared by mixing basalt fiber, aramid fiber and glass fiber, and then sequentially opening, carding, web laying and needle punching to obtain the corrosion-resistant layer.

[0066] In this invention, the mass ratio of basalt fiber, aramid fiber and glass fiber is 1:3:2 to 3, preferably 1:3:2.2 to 2.8, more preferably 1:3:2.4 to 2.6, and even more preferably 1:3:2.5; wherein the basalt fiber, aramid fiber and glass fiber all have acid and alkali resistance, high temperature resistance and chemical stability, which can ensure the stable operation of the filter material in high temperature environment and improve the service life of the filter material.

[0067] In this invention, the reinforcing layer is prepared by mixing aramid fibers with polymer fibers and then sequentially opening, carding, web laying, and needle punching to obtain the reinforcing layer.

[0068] In this invention, the polymer fiber is one of polyimide fiber, nylon 66 and polyetheretherketone fiber.

[0069] In this invention, the mass ratio of aramid to polymer fiber is 35-50:50-65, preferably 38-48:53-62, more preferably 40-45:55-60, and even more preferably 43:58.

[0070] In this invention, the reinforcing layer can improve the tensile strength of the filter material, reduce wear and tear, and extend the service life of the filter material.

[0071] In this invention, the base fabric layer is polytetrafluoroethylene nonwoven fabric.

[0072] In this invention, the mass ratio of the corrosion-resistant layer, the reinforcing layer and the base fabric layer is 35-60:40-65:40-60, preferably 38-58:43-62:43-58, more preferably 40-55:45-60:45-55, and even more preferably 45-50:50-55:48-50.

[0073] The aramid fibers in the corrosion-resistant layer and the reinforcing layer have a fineness of 1.5–3 dtex, a crimp of 10–15%, and a crimp count of 12–16 per 25 mm.

[0074] The present invention also provides a method for preparing the above-mentioned filter material, comprising the following steps:

[0075] 1) The corrosion-resistant layer and the base fabric layer are stacked on the upper and lower surfaces of the reinforcing layer, respectively, and needle-punched to obtain a three-dimensional felt-like material;

[0076] 2) Using a three-dimensional felt-like material as a substrate, spinning is performed directly on the surface of the corrosion-resistant layer to obtain an adsorption layer, and a filter layer is prepared on the surface of the adsorption layer.

[0077] Preparation process such as Figure 2 As shown.

[0078] The needle-punching process includes two steps: pre-needling and main needle-punching. The depth of pre-needling is 10–14 mm, and the density of pre-needling is 70–140 needles / cm². 2 The depth of the main needle insertion is 6–12 mm, and the needle density is 1000–1500 needles / cm². 2 .

[0079] In this invention, the basis weight of the three-dimensional felt-like material is 200–800 g / m³. 2 Preferably, it is 300–700 g / m³ 2 More preferably 400–600 g / m 2 More preferably 500g / m 2 .

[0080] In this invention, the basis weight of the adsorption layer is 2.5–4 g / m³. 2 Preferably, it is 2.8–3.8 g / m³. 2 More preferably 3-3.5 g / m 2 More preferably 3.2 g / m 2 .

[0081] In this invention, the basis weight of the filter layer is 3-4 g / m³. 2 Preferably, it is 3.2–3.8 g / m³. 2 More preferably, it is 3.4–3.6 g / m³. 2 More preferably 3.5g / m 2 .

[0082] The present invention also provides the application of the above-mentioned filter material in the removal of harmful gases.

[0083] In this invention, the filter material can be made into filter bags or filter cartridges, and used as a dust removal device in the fields of coal combustion, thermal power generation, asphalt, steel and waste incineration.

[0084] When the filter material is prepared into a filter cartridge, the preferred basis weight of the three-dimensional felt-like material is 200–350 g / m³. 2 More preferably 250–300 g / m 2 .

[0085] In this invention, the applicable temperature of the filter material is 0 to 280°C, preferably 230 to 260°C.

[0086] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0087] Example 1

[0088] (1) Preparation of corrosion-resistant layer: Basalt fiber, aramid (fineness of 1.5dtex, crimp of 10%, crimp number of 12 / 25mm) and glass fiber in a mass ratio of 1:3:2 are mixed and then opened, combed, laid into a web and needle punched in sequence to form corrosion-resistant layer.

[0089] (2) Preparation of the reinforcing layer: Aramid (fineness of 1.5dtex, crimp of 10%, crimp number of 12 / 25mm) with a mass ratio of 40:60 was mixed with nylon 66 and then opened, combed, laid web and needle punched in sequence to obtain the reinforcing layer.

[0090] (3) The corrosion-resistant layer and the base fabric layer (polytetrafluoroethylene nonwoven fabric) are stacked on the upper and lower surfaces of the reinforcing layer, and the needle punching depth is 10 mm and the needle punching density is 80 needles / cm. 2 Under certain conditions, pre-needling is performed to form a preliminary embryo mat. Then, the embryo mat is subjected to main acupuncture using upper and lower main acupuncture machines. The depth of the main acupuncture is 6 mm, and the density of the main acupuncture is 1000 needles / cm. 2 The total weight is 350g / m³. 2 A three-dimensional felt-like material; wherein the mass ratio of the corrosion-resistant layer to the reinforcing layer is 35:65, and the mass ratio of the base fabric layer to the reinforcing layer is 45:55.

[0091] (4) Preparation of the adsorption layer:

[0092] Activated carbon with a mass ratio of 1:2 was mixed with 10 wt% hydrogen peroxide solution and oxidized at 30°C for 12 h. After treatment, the mixture was filtered and washed with deionized water until the filtrate was neutral. The filtrate was then dried under vacuum to obtain preliminarily modified activated carbon. Melamine, urea, and 25 wt% ammonia were mixed in a mass ratio of 2:1:1 to obtain a mixed solution. The preliminarily modified activated carbon was then mixed with the above mixed solution at a ratio of 1 g:1.6 mL, impregnated for 12 h, and dried. The mixture was then placed in an activation furnace and a mixture of ammonia and nitrogen in a volume ratio of 1:1 was introduced. The temperature was raised to 850°C and treated at high temperature for 2 h. After the heat treatment was completed, the mixture was naturally cooled to obtain modified activated carbon with alkaline functional groups on the surface.

[0093] Polyetheretherketone (PEEK) was dissolved in hexafluoroisopropanol to prepare a 5 wt% PEEK solution. Modified activated carbon was added, with a mass ratio of 20:80 between the modified activated carbon and PEEK. The mixture was stirred at room temperature for 8 hours to obtain a modified activated carbon / PEEK spinning solution. This solution was then added to a syringe. The three-dimensional felt-like material prepared in step (3) was used as the receiving substrate. The spinning conditions were adjusted as follows: temperature 25°C, humidity 10%, spinning voltage 18 kV, spinning flow rate 0.3 mL / h, spinning distance 15 cm, and airflow velocity 40 m / s. Airflow-assisted electrospinning was performed on the corrosion-resistant layer surface of the three-dimensional felt-like material to obtain an adsorption layer with a basis weight of 3 g / m³. 2 .

[0094] (5) Preparation of the filter layer: A PTFE aqueous dispersion containing 45 wt% polytetrafluoroethylene (PTFE, Zhejiang Gertes Environmental Protection Special Materials Co., Ltd.), 6 wt% nonionic surfactant (polyoxyethylene ether), and 2 wt% foaming agent (sodium dodecyl sulfate) was prepared. The PTFE dispersion was used to prepare a foaming coating finishing liquid. The collected foam was then coated onto the upper surface of the above adsorption layer using a doctor blade, with a coating amount of 0.8 g / m². 2 Then, a layer of PTFE microporous membrane is hot-pressed onto the surface (hot-pressing temperature: 220℃, time: 8s, pressure: 1.5Mpa) to obtain a high-temperature resistant filter material containing a filter layer. The production standard for the above PTFE microporous membrane is T / ZZB 0067-2016, with a basis weight of 3g / m³. 2 Thickness: 15μm; Pore size: 2.5μm; Air permeability: 50L / m³ 2 • The tensile breaking strength is 2.7 MPa in the longitudinal direction and 2.5 MPa in the transverse direction, and the elongation at break is 70% in the longitudinal direction and 70% in the transverse direction.

[0095] The adsorption, filtration, and mechanical properties of the high-temperature resistant filter material prepared in this embodiment were tested, and the test results are as follows:

[0096] Adsorption performance test: A certain amount of the modified activated carbon prepared in step (4) was placed in an alumina pot, and then the alumina pot was placed in a thermogravimetric analyzer. First, high-purity N2 was introduced for purging, and the adsorption was measured at 5℃·min. -1 The temperature is increased to the adsorption temperature, and then H2S gas is switched. Once the mass of activated carbon remains constant, adsorption saturation is achieved. The adsorption capacity is calculated based on the mass difference of activated carbon before and after adsorption. At high temperatures, the maximum saturated adsorption capacity of activated carbon for H2S can reach 70.56 mg / g.

[0097] Filtration performance testing: The filtration performance of the samples was tested using the LZC-K1 filter media comprehensive performance testing system. The test conditions were based on European standard EN1822-3, with a test flow rate range of 10–100 L / min, a measured resistance range of 0–1000 Pa, and a test area of ​​100 cm².2 The dust source tested was NaCl aerosol. The material's filtration efficiency can reach up to 99.88%.

[0098] Mechanical property testing at high temperatures: Tensile testing at high temperatures follows the standard for room temperature tensile testing. The test samples are placed in a testing machine equipped with a high-temperature oven. When the oven reaches 250°C, the sample is held at this temperature for 10 minutes before the tensile test is performed, obtaining the high-temperature tensile data. After continuous high-temperature aging at 250°C, the material's strength retention rate is >90%.

[0099] Example 2

[0100] (1) Preparation of corrosion-resistant layer: Basalt fiber, aramid (fineness of 1.5dtex, crimp of 10%, crimp number of 12 / 25mm) and glass fiber in a mass ratio of 1:3:2 are mixed and then opened, combed, laid into a web and needle punched in sequence to form corrosion-resistant layer.

[0101] (2) Preparation of the reinforcing layer: Aramid (fineness of 1.5dtex, crimp of 10%, crimp number of 12 / 25mm) with a mass ratio of 40:60 was mixed with nylon 66 and then opened, combed, laid web and needle punched in sequence to obtain the reinforcing layer.

[0102] (3) The corrosion-resistant layer and the base fabric layer (polytetrafluoroethylene nonwoven fabric) are stacked on the upper and lower surfaces of the reinforcing layer, and the needle punching depth is 10 mm and the needle punching density is 80 needles / cm. 2 Under certain conditions, pre-needling is performed to form a preliminary embryo mat. Then, the embryo mat is subjected to main acupuncture using upper and lower main acupuncture machines. The depth of the main acupuncture is 6 mm, and the density of the main acupuncture is 1000 needles / cm. 2 The total weight is 380g / m³. 2 A three-dimensional felt-like material; wherein the mass ratio of the corrosion-resistant layer to the reinforcing layer is 35:65, and the mass ratio of the base fabric layer to the reinforcing layer is 45:55.

[0103] (4) Preparation of the adsorption layer:

[0104] Activated carbon with a mass ratio of 1:2 was mixed with 10wt% hydrogen peroxide solution and oxidized at 30℃ for 12h. After treatment, the mixture was filtered and washed with deionized water until the filtrate was neutral. The filtrate was then dried under vacuum to obtain preliminarily modified activated carbon. Melamine, urea and 25wt% ammonia were mixed in a mass ratio of 2:1:1 to obtain a mixed solution. The preliminarily modified activated carbon in the above mixed solution was then mixed and impregnated at a ratio of 1g:1.6mL for 12h and dried. The mixture was then placed in an activation furnace and a mixture of ammonia and nitrogen in a volume ratio of 1:1.2 was introduced. The temperature was raised to 850℃ and treated at high temperature for 2h. After the heat treatment was completed, the mixture was naturally cooled to obtain modified activated carbon with alkaline functional groups on the surface.

[0105] Polyetheretherketone (PEEK) was dissolved in hexafluoroisopropanol to prepare a 5 wt% PEEK solution. Modified activated carbon was added, with a mass ratio of 20:80 between the modified activated carbon and PEEK. The mixture was stirred at room temperature for 8 hours to obtain a modified activated carbon / PEEK spinning solution. This solution was then added to a syringe. The three-dimensional felt-like material prepared in step (3) was used as the receiving substrate. The spinning conditions were adjusted as follows: temperature 25°C, humidity 10%, spinning voltage 18 kV, spinning flow rate 0.3 mL / h, spinning distance 15 cm, and airflow velocity 40 m / s. Airflow-assisted electrospinning was performed on the corrosion-resistant layer surface of the three-dimensional felt-like material to obtain an adsorption layer with a basis weight of 3 g / m³. 2 .

[0106] (5) Preparation of the filter layer: A PTFE aqueous dispersion containing 45 wt% polytetrafluoroethylene (PTFE, Zhejiang Gertes Environmental Protection Special Materials Co., Ltd.), 6 wt% nonionic surfactant (polyoxyethylene ether), and 2 wt% foaming agent (sodium dodecyl sulfate) was prepared. The PTFE dispersion was used to prepare a foaming coating finishing liquid. The collected foam was then coated onto the upper surface of the above adsorption layer using a doctor blade, with a coating amount of 0.8 g / m². 2 Then, a layer of PTFE microporous membrane is hot-pressed onto the surface (hot-pressing temperature: 220℃, time: 8s, pressure: 1.5Mpa) to obtain a high-temperature resistant filter material containing a filter layer. The production standard for the above PTFE microporous membrane is T / ZZB 0067-2016, with a basis weight of 3g / m³. 2 Thickness: 15μm; Pore size: 2.5μm; Air permeability: 50L / m³ 2 • The tensile breaking strength is 2.7 MPa in the longitudinal direction and 2.5 MPa in the transverse direction, and the elongation at break is 70% in the longitudinal direction and 70% in the transverse direction.

[0107] The adsorption, filtration, and mechanical properties of the high-temperature resistant filter material prepared in this embodiment were tested, and the test results are as follows:

[0108] Adsorption performance test: A certain amount of the modified activated carbon prepared in step (4) was placed in an alumina pot, and then the alumina pot was placed in a thermogravimetric analyzer. First, high-purity N2 was introduced for purging, and the adsorption was measured at 5℃·min. -1 The temperature is increased to the adsorption temperature, and then H2S gas is switched. Once the mass of activated carbon remains constant, adsorption saturation is achieved. The adsorption capacity is calculated based on the mass difference of activated carbon before and after adsorption. At high temperatures, the maximum saturated adsorption capacity of activated carbon for H2S can reach 69.28 mg / g.

[0109] Filtration performance testing: The filtration performance of the samples was tested using the LZC-K1 filter media comprehensive performance testing system. The test conditions were based on European standard EN1822-3, with a test flow rate range of 10–100 L / min, a measured resistance range of 0–1000 Pa, and a test area of ​​100 cm². 2 The dust source tested was NaCl aerosol. The material's filtration efficiency can reach up to 99.86%.

[0110] Mechanical property testing at high temperatures: Tensile testing at high temperatures follows the standard for room temperature tensile testing. The test samples are placed in a testing machine equipped with a high-temperature oven. When the oven reaches 250°C, the sample is held at this temperature for 10 minutes before the tensile test is performed, obtaining the high-temperature tensile data. After continuous high-temperature aging at 250°C, the material's strength retention rate is >90%.

[0111] Example 3

[0112] (1) Preparation of corrosion-resistant layer: Basalt fiber, aramid (fineness of 1.5dtex, crimp of 10%, crimp number of 12 / 25mm) and glass fiber in a mass ratio of 1:3:2 are mixed and then opened, combed, laid into a web and needle punched in sequence to form corrosion-resistant layer.

[0113] (2) Preparation of the reinforcing layer: Aramid (fineness of 1.5dtex, crimp of 10%, crimp number of 12 / 25mm) with a mass ratio of 40:60 was mixed with nylon 66 and then opened, combed, laid web and needle punched in sequence to obtain the reinforcing layer.

[0114] (3) The corrosion-resistant layer and the base fabric layer (polytetrafluoroethylene nonwoven fabric) are stacked on the upper and lower surfaces of the reinforcing layer, and the needle punching depth is 12 mm and the needle punching density is 100 needles / cm. 2 Under certain conditions, pre-needling is performed to form a preliminary embryo mat. Then, the embryo mat is subjected to main acupuncture using upper and lower main acupuncture machines. The depth of the main acupuncture is 6 mm, and the density of the main acupuncture is 1000 needles / cm. 2 The total weight is 350g / m³. 2 A three-dimensional felt-like material; wherein the mass ratio of the corrosion-resistant layer to the reinforcing layer is 35:65, and the mass ratio of the base fabric layer to the reinforcing layer is 45:55.

[0115] (4) Preparation of the adsorption layer:

[0116] Activated carbon with a mass ratio of 1:3 was mixed with 20wt% hydrogen peroxide solution and oxidized at 30℃ for 12h. After treatment, the mixture was filtered and washed with deionized water until the filtrate was neutral. The filtrate was then dried under vacuum to obtain preliminarily modified activated carbon. Melamine, urea and 25wt% ammonia were mixed in a mass ratio of 2:1:2 to obtain a mixed solution. The preliminarily modified activated carbon in the above mixed solution was then mixed and impregnated at a ratio of 1g:1.8mL for 12h and dried. The mixture was then placed in an activation furnace and a mixture of ammonia and nitrogen gas with a volume ratio of 1:1.5 was introduced. The temperature was raised to 850℃ and treated at high temperature for 3h. After the heat treatment was completed, the mixture was naturally cooled to obtain modified activated carbon with alkaline functional groups on the surface.

[0117] Polyetheretherketone (PEEK) was dissolved in hexafluoroisopropanol to prepare a 5 wt% PEEK solution. Modified activated carbon was added, with a mass ratio of 20:80 between the modified activated carbon and PEEK. The mixture was stirred at room temperature for 8 hours to obtain a modified activated carbon / PEEK spinning solution. This solution was then added to a syringe. The three-dimensional felt-like material prepared in step (3) was used as the receiving substrate. The spinning conditions were adjusted as follows: temperature 25°C, humidity 10%, spinning voltage 18 kV, spinning flow rate 0.3 mL / h, spinning distance 15 cm, and airflow velocity 40 m / s. Airflow-assisted electrospinning was performed on the corrosion-resistant layer surface of the three-dimensional felt-like material to obtain an adsorption layer with a basis weight of 3 g / m³. 2 .

[0118] (5) Preparation of the filter layer: Prepare a PTFE aqueous dispersion containing 45wt% polytetrafluoroethylene (PTFE, Zhejiang Gertes Environmental Protection Special Materials Co., Ltd.), 6wt% nonionic surfactant (polyoxyethylene ether), and 2wt% foaming agent (sodium dodecyl sulfate). Apply the collected foam to the upper surface of the above adsorption layer using a scraper, with a coating amount of 0.8g / m³. 2 Then, a layer of PTFE microporous membrane is hot-pressed onto the surface (hot-pressing temperature: 220℃, time: 8s, pressure: 1.5Mpa) to obtain a high-temperature resistant filter material containing a filter layer. The production standard for the above PTFE microporous membrane is T / ZZB 0067-2016, with a basis weight of 3g / m³. 2 Thickness: 15μm; Pore size: 2.5μm; Air permeability: 50L / m³ 2 • The tensile breaking strength is 2.7 MPa in the longitudinal direction and 2.5 MPa in the transverse direction, and the elongation at break is 70% in the longitudinal direction and 70% in the transverse direction.

[0119] The adsorption, filtration, and mechanical properties of the high-temperature resistant filter material prepared in this embodiment were tested, and the test results are as follows:

[0120] Adsorption performance test: A certain amount of the modified activated carbon prepared in step (4) was placed in an alumina pot, and then the alumina pot was placed in a thermogravimetric analyzer. First, high-purity N2 was introduced for purging, and the adsorption was measured at 5℃·min. -1 The temperature is increased to the adsorption temperature, and then H2S gas is switched. Once the mass of activated carbon is constant, adsorption saturation is reached. The adsorption capacity is calculated by the mass difference of activated carbon before and after adsorption. At high temperatures, the maximum saturated adsorption capacity of activated carbon for H2S can reach 71.23 mg / g.

[0121] Filtration performance testing: The filtration performance of the samples was tested using the LZC-K1 filter media comprehensive performance testing system. The test conditions were based on European standard EN1822-3, with a test flow rate range of 10–100 L / min, a measured resistance range of 0–1000 Pa, and a test area of ​​100 cm². 2 The dust source tested was NaCl aerosol. The material's filtration efficiency can reach up to 99.87%.

[0122] Mechanical property testing at high temperatures: Tensile testing at high temperatures follows the standard for room temperature tensile testing. The test samples are placed in a testing machine equipped with a high-temperature oven. When the oven reaches 250°C, the sample is held at this temperature for 10 minutes before the tensile test is performed, obtaining the high-temperature tensile data. After continuous high-temperature aging at 250°C, the material's strength retention rate is >90%.

[0123] Example 4

[0124] (1) Preparation of corrosion-resistant layer: Basalt fiber, aramid (fineness of 2.5dtex, crimp of 12%, crimp number of 14 / 25mm) and glass fiber in a mass ratio of 1:3:3 are mixed and then opened, carded, laid into a web and needle punched in sequence to form corrosion-resistant layer.

[0125] (2) Preparation of the reinforcing layer: Aramid (fineness of 1.5dtex, crimp of 10%, crimp number of 12 / 25mm) with a mass ratio of 40:60 was mixed with nylon 66 and then opened, combed, laid web and needle punched in sequence to obtain the reinforcing layer.

[0126] (3) The corrosion-resistant layer and the base fabric layer (polytetrafluoroethylene nonwoven fabric) are stacked on the upper and lower surfaces of the reinforcing layer, and the needle punching depth is 12 mm and the needle punching density is 100 needles / cm. 2 Under certain conditions, pre-needling is performed to form a preliminary embryo mat. Then, the embryo mat is subjected to main acupuncture using upper and lower main acupuncture machines. The depth of the main acupuncture is 6 mm, and the density of the main acupuncture is 1000 needles / cm. 2 The total weight is 350g / m³. 2 A three-dimensional felt-like material; wherein the mass ratio of the corrosion-resistant layer to the reinforcing layer is 35:65, and the mass ratio of the base fabric layer to the reinforcing layer is 45:55.

[0127] (4) Preparation of the adsorption layer:

[0128] Activated carbon with a mass ratio of 1:3 was mixed with 20wt% hydrogen peroxide solution and oxidized at 30℃ for 12h. After treatment, the mixture was filtered and washed with deionized water until the filtrate was neutral. The filtrate was then dried under vacuum to obtain preliminarily modified activated carbon. Melamine, urea and 25wt% ammonia were mixed in a mass ratio of 2:1:2 to obtain a mixed solution. The preliminarily modified activated carbon in the above mixed solution was then mixed and impregnated at a ratio of 1g:1.8mL for 12h and dried. The mixture was then placed in an activation furnace and a mixture of ammonia and nitrogen gas with a volume ratio of 1:1.5 was introduced. The temperature was raised to 850℃ and treated at high temperature for 3h. After the heat treatment was completed, the mixture was naturally cooled to obtain modified activated carbon with alkaline functional groups on the surface.

[0129] Polyetheretherketone (PEEK) was dissolved in hexafluoroisopropanol to prepare a 5 wt% PEEK solution. Modified activated carbon was added, with a mass ratio of 15:85 between the modified activated carbon and PEEK. The mixture was stirred at room temperature for 8 hours to obtain a modified activated carbon / PEEK spinning solution. This solution was then added to a syringe. The three-dimensional felt-like material prepared in step (3) was used as the receiving substrate. The spinning conditions were adjusted as follows: temperature 25°C, humidity 10%, spinning voltage 18 kV, spinning flow rate 0.3 mL / h, spinning distance 15 cm, and airflow velocity 40 m / s. Airflow-assisted electrospinning was performed on the corrosion-resistant layer surface of the three-dimensional felt-like material to obtain an adsorption layer with a basis weight of 3 g / m³. 2 .

[0130] (5) Preparation of the filter layer: Prepare a PTFE aqueous dispersion containing 45wt% polytetrafluoroethylene (PTFE, Zhejiang Gertes Environmental Protection Special Materials Co., Ltd.), 6wt% nonionic surfactant (polyoxyethylene ether), and 2wt% foaming agent (sodium dodecyl sulfate). Apply the collected foam to the upper surface of the above adsorption layer using a scraper, with a coating amount of 0.8g / m³. 2 Then, a layer of PTFE microporous membrane is hot-pressed onto the surface (hot-pressing temperature: 220℃, time: 8s, pressure: 1.5Mpa) to obtain a high-temperature resistant filter material containing a filter layer. The production standard for the above PTFE microporous membrane is T / ZZB 0067-2016, with a basis weight of 3g / m³. 2 Thickness: 15μm; Pore size: 2.5μm; Air permeability: 50L / m³ 2 • The tensile breaking strength is 2.7 MPa in the longitudinal direction and 2.5 MPa in the transverse direction, and the elongation at break is 70% in the longitudinal direction and 70% in the transverse direction.

[0131] The adsorption, filtration, and mechanical properties of the high-temperature resistant filter material prepared in this embodiment were tested, and the test results are as follows:

[0132] Adsorption performance test: A certain amount of the modified activated carbon prepared in step (4) was placed in an alumina pot, and then the alumina pot was placed in a thermogravimetric analyzer. First, high-purity N2 was introduced for purging, and the adsorption was measured at 5℃·min. -1 The temperature is increased to the adsorption temperature, and then H2S gas is switched. Once the mass of activated carbon remains constant, adsorption saturation is achieved. The adsorption capacity is calculated based on the mass difference of activated carbon before and after adsorption. At high temperatures, the maximum saturated adsorption capacity of activated carbon for H2S can reach 71.35 mg / g.

[0133] Filtration performance testing: The filtration performance of the samples was tested using the LZC-K1 filter media comprehensive performance testing system. The test conditions were based on European standard EN1822-3, with a test flow rate range of 10–100 L / min, a measured resistance range of 0–1000 Pa, and a test area of ​​100 cm². 2 The dust source tested was NaCl aerosol. The material's filtration efficiency can reach up to 99.87%.

[0134] Mechanical property testing at high temperatures: Tensile testing at high temperatures follows the standard for room temperature tensile testing. The test samples are placed in a testing machine equipped with a high-temperature oven. When the oven reaches 250°C, the sample is held at this temperature for 10 minutes before the tensile test is performed, obtaining the high-temperature tensile data. After continuous high-temperature aging at 250°C, the material's strength retention rate is >90%.

[0135] Example 5

[0136] (1) Preparation of corrosion-resistant layer: Basalt fiber, aramid (fineness of 1.5dtex, crimp of 10%, crimp number of 12 / 25mm) and glass fiber in a mass ratio of 1:3:2 are mixed and then opened, combed, laid into a web and needle punched in sequence to form corrosion-resistant layer.

[0137] (2) Preparation of the reinforcing layer: Aramid (fineness of 1.8 dtex, crimp of 14%, crimp number of 15 / 25mm) with a mass ratio of 40:60 was mixed with nylon 66 and then opened, combed, laid web and needle punched in sequence to obtain the reinforcing layer.

[0138] (3) The corrosion-resistant layer and the base fabric layer (polytetrafluoroethylene nonwoven fabric) are stacked on the upper and lower surfaces of the reinforcing layer, and the needle punching depth is 12 mm and the needle punching density is 100 needles / cm. 2 Under certain conditions, pre-needling is performed to form a preliminary embryo mat. Then, the embryo mat is subjected to main acupuncture using upper and lower main acupuncture machines. The depth of the main acupuncture is 6 mm, and the density of the main acupuncture is 1000 needles / cm. 2 The total weight is 350g / m³. 2 A three-dimensional felt-like material; wherein the mass ratio of the corrosion-resistant layer to the reinforcing layer is 35:65, and the mass ratio of the base fabric layer to the reinforcing layer is 45:55.

[0139] (4) Preparation of the adsorption layer:

[0140] Activated carbon with a mass ratio of 1:3 was mixed with 20wt% hydrogen peroxide solution and oxidized at 30℃ for 12h. After treatment, the mixture was filtered and washed with deionized water until the filtrate was neutral. The filtrate was then dried under vacuum to obtain preliminarily modified activated carbon. Melamine, urea, and 25wt% ammonia were mixed in a mass ratio of 2:1:2 to obtain a mixed solution. The preliminarily modified activated carbon in the above mixed solution was then mixed and impregnated at a ratio of 1g:1.6mL for 12h and dried. The mixture was then placed in an activation furnace and a mixture of ammonia and nitrogen in a volume ratio of 1:1.2 was introduced. The temperature was raised to 850℃ and treated at high temperature for 3h. After the heat treatment was completed, the mixture was naturally cooled to obtain modified activated carbon with alkaline functional groups on the surface.

[0141] Polyetheretherketone (PEEK) was dissolved in hexafluoroisopropanol to prepare a 5 wt% PEEK solution. Modified activated carbon was added, with a mass ratio of 15:85 between the modified activated carbon and PEEK. The mixture was stirred at room temperature for 8 hours to obtain a modified activated carbon / PEEK spinning solution. This solution was then added to a syringe. The three-dimensional felt-like material prepared in step (3) was used as the receiving substrate. The spinning conditions were adjusted as follows: temperature 25°C, humidity 10%, spinning voltage 18 kV, spinning flow rate 0.3 mL / h, spinning distance 15 cm, and airflow velocity 40 m / s. Airflow-assisted electrospinning was performed on the corrosion-resistant layer surface of the three-dimensional felt-like material to obtain an adsorption layer with a basis weight of 3 g / m³. 2 .

[0142] (5) Preparation of the filter layer: Prepare a PTFE aqueous dispersion containing 45wt% polytetrafluoroethylene (PTFE, Zhejiang Gertes Environmental Protection Special Materials Co., Ltd.), 6wt% nonionic surfactant (polyoxyethylene ether), and 2wt% foaming agent (sodium dodecyl sulfate). Apply the collected foam to the upper surface of the above adsorption layer using a scraper, with a coating amount of 0.8g / m³. 2 Then, a layer of PTFE microporous membrane is hot-pressed onto the surface (hot-pressing temperature: 220℃, time: 8s, pressure: 1.5Mpa) to obtain a high-temperature resistant filter material containing a filter layer. The production standard for the above PTFE microporous membrane is T / ZZB 0067-2016, with a basis weight of 3g / m³. 2 Thickness: 15μm; Pore size: 2.5μm; Air permeability: 50L / m³ 2 • The tensile breaking strength is 2.7 MPa in the longitudinal direction and 2.5 MPa in the transverse direction, and the elongation at break is 70% in the longitudinal direction and 70% in the transverse direction.

[0143] The adsorption, filtration, and mechanical properties of the high-temperature resistant filter material prepared in this embodiment were tested, and the test results are as follows:

[0144] Adsorption performance test: A certain amount of the modified activated carbon prepared in step (4) was placed in an alumina pot, and then the alumina pot was placed in a thermogravimetric analyzer. First, high-purity N2 was introduced for purging, and the adsorption was measured at 5℃·min. -1 The temperature is increased to the adsorption temperature, and then H2S gas is switched. Once the mass of activated carbon remains constant, adsorption saturation is achieved. The adsorption capacity is calculated based on the mass difference of activated carbon before and after adsorption. At high temperatures, the maximum saturated adsorption capacity of activated carbon for H2S can reach 70.47 mg / g.

[0145] Filtration performance testing: The filtration performance of the samples was tested using the LZC-K1 filter media comprehensive performance testing system. The test conditions were based on European standard EN1822-3, with a test flow rate range of 10–100 L / min, a measured resistance range of 0–1000 Pa, and a test area of ​​100 cm². 2 The dust source tested was NaCl aerosol. The material's filtration efficiency can reach up to 99.87%.

[0146] Mechanical property testing at high temperatures: Tensile testing at high temperatures follows the standard for room temperature tensile testing. The test samples are placed in a testing machine equipped with a high-temperature oven. When the oven reaches 250°C, the sample is held at this temperature for 10 minutes before the tensile test is performed, obtaining the high-temperature tensile data. After continuous high-temperature aging at 250°C, the material's strength retention rate is >90%.

[0147] Example 6

[0148] (1) Preparation of corrosion-resistant layer: Basalt fiber, aramid (fineness of 1.5dtex, crimp of 10%, crimp number of 12 / 25mm) and glass fiber in a mass ratio of 1:3:2 are mixed and then opened, combed, laid into a web and needle punched in sequence to form corrosion-resistant layer.

[0149] (2) Preparation of the reinforcing layer: Aramid (fineness of 1.5dtex, crimp of 10%, crimp number of 12 / 25mm) with a mass ratio of 40:60 was mixed with nylon 66 and then opened, combed, laid web and needle punched in sequence to obtain the reinforcing layer.

[0150] (3) The corrosion-resistant layer and the base fabric layer (polytetrafluoroethylene nonwoven fabric) are stacked on the upper and lower surfaces of the reinforcing layer, and the needle punching depth is 12 mm and the needle punching density is 100 needles / cm. 2 Under certain conditions, pre-needling is performed to form a preliminary felt, followed by main needling using upper and lower main needling machines. The depth of main needling is 8 mm, and the main needling density is 1200 needles / cm². 2 The total weight is 350g / m³. 2A three-dimensional felt-like material; wherein the mass ratio of the corrosion-resistant layer to the reinforcing layer is 35:65, and the mass ratio of the base fabric layer to the reinforcing layer is 55:45.

[0151] (4) Preparation of the adsorption layer:

[0152] Activated carbon with a mass ratio of 1:3 was mixed with 20wt% hydrogen peroxide solution and oxidized at 30℃ for 12h. After treatment, the mixture was filtered and washed with deionized water until the filtrate was neutral. The filtrate was then dried under vacuum to obtain preliminarily modified activated carbon. Melamine, urea and 25wt% ammonia were mixed in a mass ratio of 2:1:2 to obtain a mixed solution. The preliminarily modified activated carbon in the above mixed solution was then mixed and impregnated at a ratio of 1g:1.6mL for 12h and dried. The mixture was then placed in an activation furnace and a mixture of ammonia and nitrogen in a volume ratio of 1:1.3 was introduced. The temperature was raised to 880℃ and treated at high temperature for 3h. After the heat treatment was completed, the mixture was naturally cooled to obtain modified activated carbon with alkaline functional groups on the surface.

[0153] Polyetheretherketone (PEEK) was dissolved in hexafluoroisopropanol to prepare a 5 wt% PEEK solution. Modified activated carbon was added, with a mass ratio of 15:85 between the modified activated carbon and PEEK. The mixture was stirred at room temperature for 8 hours to obtain a modified activated carbon / PEEK spinning solution. This solution was then added to a syringe. The three-dimensional felt-like material prepared in step (3) was used as the receiving substrate. The spinning conditions were adjusted as follows: temperature 25°C, humidity 10%, spinning voltage 18 kV, spinning flow rate 0.3 mL / h, spinning distance 15 cm, and airflow velocity 40 m / s. Airflow-assisted electrospinning was performed on the corrosion-resistant layer surface of the three-dimensional felt-like material to obtain an adsorption layer with a basis weight of 3 g / m³. 2 .

[0154] (5) Preparation of the filter layer: Prepare a PTFE aqueous dispersion containing 45wt% polytetrafluoroethylene (PTFE, Zhejiang Gertes Environmental Protection Special Materials Co., Ltd.), 6wt% nonionic surfactant (polyoxyethylene ether), and 2wt% foaming agent (sodium dodecyl sulfate). Apply the collected foam to the upper surface of the above adsorption layer using a scraper, with a coating amount of 0.8g / m³. 2 Then, a layer of PTFE microporous membrane is hot-pressed onto the surface (hot-pressing temperature: 220℃, time: 8s, pressure: 1.5Mpa) to obtain a high-temperature resistant filter material containing a filter layer. The production standard for the above PTFE microporous membrane is T / ZZB 0067-2016, with a basis weight of 3g / m³. 2 Thickness: 15μm; Pore size: 2.5μm; Air permeability: 50L / m³ 2 • The tensile breaking strength is 2.7 MPa in the longitudinal direction and 2.5 MPa in the transverse direction, and the elongation at break is 70% in the longitudinal direction and 70% in the transverse direction.

[0155] The adsorption, filtration, and mechanical properties of the high-temperature resistant filter material prepared in this embodiment were tested, and the test results are as follows:

[0156] Adsorption performance test: A certain amount of the modified activated carbon prepared in step (4) was placed in an alumina pot, and then the alumina pot was placed in a thermogravimetric analyzer. First, high-purity N2 was introduced for purging, and the adsorption was measured at 5℃·min. -1 The temperature is increased to the adsorption temperature, and then H2S gas is switched. Once the mass of activated carbon is constant, adsorption saturation is reached. The adsorption capacity is calculated by the mass difference of activated carbon before and after adsorption. At high temperatures, the saturated adsorption capacity of activated carbon for H2S can reach up to 70.93 mg / g.

[0157] Filtration performance testing: The filtration performance of the samples was tested using the LZC-K1 filter media comprehensive performance testing system. The test conditions were based on European standard EN1822-3, with a test flow rate range of 10–100 L / min, a measured resistance range of 0–1000 Pa, and a test area of ​​100 cm². 2 The dust source tested was NaCl aerosol. The material's filtration efficiency can reach up to 99.87%.

[0158] Mechanical property testing at high temperatures: Tensile testing at high temperatures follows the standard for room temperature tensile testing. The test samples are placed in a testing machine equipped with a high-temperature oven. When the oven reaches 250°C, the sample is held at this temperature for 10 minutes before the tensile test is performed, obtaining the high-temperature tensile data. After continuous high-temperature aging at 250°C, the material's strength retention rate is >90%.

[0159] Comparative Example 1

[0160] (1) Preparation of corrosion-resistant layer: Basalt fiber, aramid (fineness of 1.5dtex, crimp of 10%, crimp number of 12 / 25mm) and glass fiber in a mass ratio of 1:3:2 are mixed and then opened, combed, laid into a web and needle punched in sequence to form corrosion-resistant layer.

[0161] (2) Preparation of the reinforcing layer: Aramid (fineness of 1.5dtex, crimp of 10%, crimp number of 12 / 25mm) with a mass ratio of 40:60 was mixed with nylon 66 and then opened, combed, laid web and needle punched in sequence to obtain the reinforcing layer.

[0162] (3) The corrosion-resistant layer and the base fabric layer (polytetrafluoroethylene nonwoven fabric) are stacked on the upper and lower surfaces of the reinforcing layer, and the needle punching depth is 12 mm and the needle punching density is 100 needles / cm. 2 Under certain conditions, pre-needling is performed to form a preliminary embryo mat. Then, the embryo mat is subjected to main acupuncture using upper and lower main acupuncture machines. The depth of the main acupuncture is 6 mm, and the density of the main acupuncture is 1000 needles / cm. 2 The total weight is 350g / m³.2 A three-dimensional felt-like material; wherein the mass ratio of the corrosion-resistant layer to the reinforcing layer is 35:65, and the mass ratio of the base fabric layer to the reinforcing layer is 45:55.

[0163] (4) Preparation of the adsorption layer:

[0164] Polyetheretherketone (PEEK) was dissolved in hexafluoroisopropanol to prepare a 5 wt% PEEK solution. Unmodified activated carbon was added, with a mass ratio of activated carbon to PEEK of 20:80. The mixture was stirred at room temperature for 8 hours to obtain an activated carbon / PEEK spinning solution. This solution was then added to a syringe. The three-dimensional felt-like material prepared in step (3) was used as the receiving substrate. The spinning conditions were adjusted as follows: temperature 25°C, humidity 10%, spinning voltage 18 kV, spinning flow rate 0.3 mL / h, spinning distance 15 cm, and airflow velocity 40 m / s. Airflow-assisted electrospinning was performed on the corrosion-resistant layer surface of the three-dimensional felt-like material to obtain an adsorption layer with a basis weight of 3 g / m³. 2 .

[0165] (5) Preparation of the filter layer: Prepare a PTFE aqueous dispersion containing 45wt% polytetrafluoroethylene (PTFE, Zhejiang Gertes Environmental Protection Special Materials Co., Ltd.), 6wt% nonionic surfactant (polyoxyethylene ether), and 2wt% foaming agent (sodium dodecyl sulfate). Apply the collected foam to the upper surface of the above adsorption layer using a scraper, with a coating amount of 0.8g / m³. 2 Then, a layer of PTFE microporous membrane is hot-pressed onto the surface (hot-pressing temperature: 220℃, time: 8s, pressure: 1.5Mpa) to obtain a high-temperature resistant filter material containing a filter layer. The production standard for the above PTFE microporous membrane is T / ZZB 0067-2016, with a basis weight of 3g / m³. 2 Thickness: 15μm; Pore size: 2.5μm; Air permeability: 50L / m³ 2 • The tensile breaking strength is 2.7 MPa in the longitudinal direction and 2.5 MPa in the transverse direction, and the elongation at break is 70% in the longitudinal direction and 70% in the transverse direction.

[0166] The adsorption, filtration, and mechanical properties of the high-temperature resistant filter material prepared in this embodiment were tested, and the test results are as follows:

[0167] Adsorption performance test: A certain amount of unmodified activated carbon was placed in a corundum pot, and then the corundum pot was placed in a thermogravimetric analyzer. First, high-purity N2 was passed through for purging, and the adsorption rate was 5℃·min. -1 The temperature is increased to the adsorption temperature, and then H2S gas is switched. Once the mass of activated carbon remains constant, adsorption saturation is achieved. The adsorption capacity is calculated based on the mass difference of activated carbon before and after adsorption. At high temperatures, the maximum saturated adsorption capacity of activated carbon for H2S can reach 46.87 mg / g.

[0168] Filtration performance testing: The filtration performance of the samples was tested using the LZC-K1 filter media comprehensive performance testing system. The test conditions were based on European standard EN1822-3, with a test flow rate range of 10–100 L / min, a measured resistance range of 0–1000 Pa, and a test area of ​​100 cm². 2 The dust source tested was NaCl aerosol. The material's filtration efficiency can reach up to 99.87%.

[0169] Mechanical property testing at high temperatures: Tensile testing at high temperatures follows the standard for room temperature tensile testing. The test samples are placed in a testing machine equipped with a high-temperature oven. When the oven reaches 250°C, the sample is held at this temperature for 10 minutes before the tensile test is performed, obtaining the high-temperature tensile data. After continuous high-temperature aging at 250°C, the material's strength retention rate is >90%.

[0170] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A high temperature resistant filter material capable of removing harmful gases, characterized in that, The filter layer, the adsorption layer, the corrosion-resistant layer, the reinforcing layer and the base cloth layer are sequentially stacked. The adsorption layer is a blown modified activated carbon / polyether ether ketone composite fiber membrane; The preparation method of the blown modified activated carbon / polyether ether ketone composite fiber membrane comprises the following steps: 1) The activated carbon is mixed with a strong oxidant for preliminary modification, then the preliminary modified activated carbon is mixed with a mixed solution containing melamine, urea and ammonia water for impregnation treatment, and the impregnated activated carbon is calcined at high temperature to obtain modified activated carbon with alkaline functional groups on the surface; 2) The polyether ether ketone, organic solvent and modified activated carbon are mixed to obtain a modified activated carbon / polyether ether ketone spinning solution, and spinning is performed to obtain a blown modified activated carbon / polyether ether ketone composite fiber membrane.

2. The high temperature resistant filter material capable of removing harmful gases according to claim 1, characterized in that, The preliminary modification temperature in step 1) is 25-40℃, and the preliminary modification time is 12-24h; The mass-volume ratio of the preliminary modified activated carbon to the mixed solution containing melamine, urea and ammonia water is 1g:1.5-2.5mL; The mass ratio of melamine, urea and ammonia water is 2:1:1-2; The concentration of the ammonia water is 25wt%; The impregnation time is 12-18h; The high-temperature calcination temperature is 830-880℃, the high-temperature calcination time is 2-3h, and the high-temperature calcination atmosphere is a mixed atmosphere of ammonia and nitrogen; The volume ratio of ammonia to nitrogen is 1:1-1.

5.

3. The high temperature resistant filter material capable of removing harmful gases according to claim 2, characterized in that, The concentration of polyether ether ketone in the modified activated carbon / polyether ether ketone spinning solution in step 2) is 3-15wt%; The mass ratio of modified activated carbon to polyether ether ketone is 10-30:70-90.

4. The high-temperature resistant filter material capable of removing harmful gases according to any one of claims 1-3, characterized in that, The spinning temperature in step 2) is 20-30℃, the spinning humidity is 10-20%, the spinning voltage is 15-20kV, the spinning flow rate is 0.3-1mL / h, the spinning distance is 13-20cm, and the spinning airflow speed is 40-60m / s.

5. The high temperature resistant filter material capable of removing harmful gases according to claim 4, characterized in that, The preparation method of the filter layer is as follows: polytetrafluoroethylene, non-ionic surfactant, foaming agent and water are mixed to obtain a foaming coating finishing liquid, foaming treatment is performed, and the foam is scraped onto the upper surface of the adsorption layer by a doctor blade, and then a layer of polytetrafluoroethylene microporous membrane is hot pressed on the surface to obtain the filter layer; The mass ratio of polytetrafluoroethylene, non-ionic surfactant, foaming agent and water is 40-60:5-7:2-3:30-53.

6. The high temperature resistant filter material capable of removing harmful gases according to claim 5, characterized in that, The preparation method of the corrosion-resistant layer is as follows: basalt fibers, aramid fibers and glass fibers are mixed, and then opening, carding, laying and needling are sequentially performed to obtain the corrosion-resistant layer; The mass ratio of basalt fibers, aramid fibers and glass fibers is 1:3:2-3; The preparation method of the reinforcing layer is as follows: aramid fibers and high molecular fibers are mixed, and then opening, carding, laying and needling are sequentially performed to obtain the reinforcing layer; The high molecular fiber is one of polyimide fiber, nylon 66 and polyether ether ketone fiber; The mass ratio of aramid fibers to high molecular fibers is 35-50:50-65; The base cloth layer is polytetrafluoroethylene non-woven fabric.

7. The high temperature resistant filter material capable of removing harmful gases according to claim 6, characterized in that, The mass ratio of the corrosion-resistant layer, the reinforcing layer and the base cloth layer is 35-60:65-40:40-60.

8. The method for preparing the high-temperature-resistant filter material capable of removing harmful gases according to any one of claims 1-7, characterized in that, The preparation method comprises the following steps: 1) The corrosion-resistant layer and the base cloth layer are respectively stacked on the upper and lower surfaces of the reinforcing layer, and needling is formed to obtain a three-dimensional felt material; 2) Spinning is directly performed on the surface of the corrosion-resistant layer with the three-dimensional felt material as a substrate to obtain an adsorption layer, and a filter layer is prepared on the surface of the adsorption layer; The three-dimensional felt material has a grammage of 200-800 g / m 2 ; The gram weight of the adsorbing layer is 2.5~4g / m 2 ; The filter layer has a grammage of 3-4 g / m 2 .

9. The application of the high-temperature-resistant filter material capable of removing harmful gases according to any one of claims 1-7 in removing harmful gases.

Images