Multifunctional PTFE (Polytetrafluoroethylene) film with carbon dioxide gas adsorption function as well as preparation method and application of multifunctional PTFE film

Abstract

The invention discloses a multifunctional PTFE membrane capable of adsorbing carbon dioxide gas as well as a preparation method and application of the multifunctional PTFE membrane, and belongs to the technical field of PTFE membranes. The invention discloses a preparation method. The preparation method comprises the following steps: mixing 3, 3, 5, 5-tetramethyl-1H, 1H-4, 4-bipyrazole with NiSiF6. 6H2O, reacting under the catalysis of Pd to obtain SiFSiX-18-Ni-alpha, and then heating the SiFSiX-18-Ni-alpha in vacuum to obtain an ultra-microporous material; the preparation method comprises the following steps: uniformly mixing PTFE resin, an extrusion aid, a cross-linking agent and an ultra-microporous material, standing in a drying room, and then pre-pressing and calendering to obtain a PTFE blank film; degreasing and longitudinally stretching the PTFE blank film to obtain a blank film sample material; placing the blank film sample material in a drying room for standing, and then transversely stretching to obtain the PTFE film. Wherein the ultra-microporous material has strong adsorption capacity on gaseous carbon dioxide, and the adsorption capacity of CO2 cannot be influenced by a humid environment.

Description

Technical Field

[0001] The invention belongs to the technical field of PTFE membranes, and in particular relates to a multifunctional PTFE membrane capable of absorbing carbon dioxide gas and a preparation method and application thereof. Background Art

[0002] For the strict industrial flue gas treatment standards, the coated filter material in the bag dust removal system has an excellent capture effect on fine dust and is an effective means to control industrial flue gas pollution. At the same time, compared with ordinary filter materials, it has the advantages of higher filtration efficiency, easier cleaning, and longer cleaning cycle, and is favored by the majority of users.

[0003] However, ordinary coated filter materials can basically meet the dust emission requirements, but lack the ability to absorb gases such as carbon dioxide in industrial flue gas. Under the general trend, the coordinated control of multiple pollutants is an inevitable result of the development of the industrial flue gas treatment industry. Summary of the invention

[0004] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a multifunctional PTFE membrane capable of adsorbing carbon dioxide gas and a preparation method and application thereof, thereby solving the problems in the prior art.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] The method for preparing a multifunctional PTFE membrane capable of adsorbing carbon dioxide gas comprises the following steps:

[0007] 3,3,5,5-tetramethyl-1H,1H-4,4-bipyrazole and NiSiF 6 6H 2 O is mixed and reacted under Pd catalysis to obtain SiFSiX-18-Ni-α, and then SiFSiX-18-Ni-α is heated under vacuum to obtain ultra-microporous materials;

[0008] After the PTFE resin, extrusion aid, cross-linking agent and ultra-microporous material are uniformly mixed, the mixture is placed in a drying room for standing, and then pre-pressed and calendered to obtain a PTFE blank film;

[0009] Degreasing and longitudinally stretching the PTFE blank film to obtain a blank film sample;

[0010] The green film sample is placed in a drying room to stand, and then stretched transversely to obtain a PTFE film.

[0011] Furthermore, 3,3,5,5-tetramethyl-1H,1H-4,4-bipyrazole and NiSiF 6 6H 2 The molar ratio of O is (3.5-4):1.

[0012] Furthermore, the heating temperature of SiFSiX-18-Ni-α is 85°C.

[0013] Furthermore, the mass ratio of PTFE resin, extrusion aid, cross-linking agent and ultra-microporous material is 100:32:(4-5):(5-7).

[0014] Furthermore, the degreasing temperature is 190°C and the longitudinal drawing temperature is 220°C.

[0015] Furthermore, the temperatures of the stretching zones 1 to 3 of the transverse stretching are 300-320°C, 310-330°C, and 320-340°C, respectively, the temperature of the sintering zone is 340-350°C, and the stretching ratio is 20.

[0016] Furthermore, after the PTFE resin, extrusion aid, cross-linking agent and ultra-microporous material are uniformly mixed, they are placed in a drying room at a temperature of 55-60° C. for more than 24 hours;

[0017] The temperature of the drying room where the blank film sample is placed is 120° C. for 2-4 hours.

[0018] The multifunctional PTFE membrane capable of adsorbing carbon dioxide gas is prepared by using the above-mentioned method for preparing the multifunctional PTFE membrane capable of adsorbing carbon dioxide gas.

[0019] The multifunctional PTFE membrane capable of adsorbing carbon dioxide gas is used in the preparation of membrane filter material.

[0020] A filter bag comprises a membrane-coated filter material, on which the above-mentioned multifunctional PTFE film capable of absorbing carbon dioxide gas is attached.

[0021] Beneficial effects of the present invention:

[0022] 1. The ultra-microporous material (MOFs-Ni metal-organic framework) obtained by the present invention through a specific reaction has a strong adsorption capacity for gaseous carbon dioxide (the micropores have binding sites for CO2), and the adsorption capacity of CO2 will not be affected by a humid environment.

[0023] 2. This ultra-microporous material belongs to the MOFs series of substances (with multi-porous paths). When it is added to the PTFE resin, it will not block the pores of the PTFE membrane and cause the overall air permeability to decrease, and other properties of the membrane will not be invalidated.

[0024] 3. The obtained PTFE membrane is attached to the base filter material by heat coating and applied to the fields of steel / cement / waste incineration, which can effectively remove CO in the flue gas. 2 , which has a promoting effect on greenhouse gas emissions. DETAILED DESCRIPTION

[0025] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solution of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] The method for preparing a multifunctional PTFE membrane capable of adsorbing carbon dioxide gas comprises the following steps:

[0027] S1, Preparation of ultra-microporous materials: 3,3,5,5-tetramethyl-1H,1H-4,4-bipyrazole (purity 98%) was mixed with NiSiF 6 6H 2 O in a hydrothermal reactor at a molar ratio of 3.5-4:1 and react under Pd catalysis to obtain [Ni(L) 2 (SiF 6 )]n and SiFSiX-18-Ni-α metal-organic framework; then, under vacuum, SiFSiX-18-Ni-α is heated to 85°C to cause a phase transformation, increasing the number of micropores, and obtaining an ultra-microporous material.

[0028] S2, preparation of PTFE blank film; after the PTFE resin, extrusion aid, cross-linking agent and ultra-microporous material are uniformly mixed, the mixture is placed in a drying room at a temperature of 55-60° C. for more than 24 hours, and then a pre-pressing and calendering process is performed to obtain a PTFE blank film;

[0029] S3, degreasing and longitudinal stretching of the PTFE blank film: degreasing the PTFE blank film obtained in S2 to remove the extrusion aid in the mixture; and longitudinally stretching it at a longitudinal stretching ratio of 7 times;

[0030] S4, transverse stretching: placing the green film sample obtained in S3 in a drying room at a temperature of 120° C. for 2-4 hours, and then stretching it through a transverse stretching machine to obtain a finished PTFE film;

[0031] The technical scheme of the present invention is described in detail below through the following examples and comparative examples; wherein the raw materials in the examples and comparative examples are as follows:

[0032] 3,3,5,5-Tetramethyl-1H,1H-4,4-bipyrazole (Shanghai Tengzhun Biotechnology Co., Ltd.);

[0033] NeA 6 6H 2 O (Shanghai Tengzhun Biotechnology Co., Ltd.) PTFE resin, manufacturer model is Daikin 104;

[0034] The extrusion aid was aviation kerosene purchased from Jinan Xinke Chemical Co., Ltd.

[0035] The cross-linking agent is acrylic acid ion exchange resin cross-linking agent purchased from Anhui Xiangyun Plastic Co., Ltd.

[0036] Example 1

[0037] S1, Preparation of ultra-microporous materials:

[0038] 3,3,5,5-tetramethyl-1H,1H-4,4-bipyrazole and NiSiF 6 6H 2 O is reacted in a hydrothermal reactor at a molar ratio of 3.5:1 and under the catalysis of Pd to obtain a SiFSiX-18-Ni-α metal-organic framework; then, the SiFSiX-18-Ni-α is heated to 85°C under vacuum to cause a phase transformation of the material, increase the number of micropores, and obtain an ultra-microporous material;

[0039] S2, Preparation of PTFE blank membrane:

[0040] After PTFE resin, extrusion aid, cross-linking agent and ultra-microporous material (mass ratio of 100:32:4:5) are mixed evenly, placed in a drying room at a temperature of 58°C for 24 hours, and then the mixture is pre-pressed by a pre-pressing machine to obtain a rod-shaped blank, and then calendered by a calendering machine to obtain a PTFE blank film with a thickness of 270 μm and a width of 13 cm;

[0041] S3, PTFE film degreasing and longitudinal stretching:

[0042] The PTFE blank film obtained in S2 is degreased and longitudinally stretched in an oven to obtain a blank film sample; wherein the degreasing temperature is 190°C, the longitudinal stretching temperature is 220°C, the longitudinal stretching ratio is 7 times, and the blank film feeding speed is 20m / min;

[0043] S4, transverse stretch:

[0044] The green film sample obtained in S3 was placed in a drying room at a temperature of 120°C for 3 hours, and then stretched transversely by a transverse stretching machine. The temperatures of stretching zones 1 to 3 were 300°C, 310°C, and 320°C, respectively, the temperature of the sintering zone was 340°C, and the stretching ratio was 20, to obtain a finished PTFE film;

[0045] Lamination application:

[0046] The finished PTFE membrane obtained in S4 is laminated on the required filter material by hot pressing to obtain a coated filter material with oleophobic effect.

[0047] Example 2

[0048] S1, Preparation of ultra-microporous materials:

[0049] 3,3,5,5-tetramethyl-1H,1H-4,4-bipyrazole and NiSiF 6 6H 2 O is reacted in a hydrothermal reactor at a molar ratio of 3.75:1 and under the catalysis of Pd to obtain a SiFSiX-18-Ni-α metal-organic framework; then, the SiFSiX-18-Ni-α is heated to 85°C under vacuum to cause a phase transformation of the material, increase the number of micropores, and obtain an ultra-microporous material;

[0050] S2, Preparation of PTFE blank membrane:

[0051] After PTFE resin, extrusion aid, cross-linking agent and ultra-microporous material (mass ratio of 100:32:5:7) are mixed evenly, placed in a drying room at a temperature of 58°C for 24 hours, and then the mixture is pre-pressed by a pre-pressing machine to obtain a rod-shaped blank, and then calendered by a calendering machine to obtain a PTFE blank film with a thickness of 270 μm and a width of 13 cm;

[0052] S3, PTFE film degreasing and longitudinal stretching:

[0053] The PTFE blank film obtained in S2 is degreased and longitudinally stretched in an oven to obtain a blank film sample; wherein the degreasing temperature is 190°C, the longitudinal stretching temperature is 220°C, the longitudinal stretching ratio is 7, and the blank film feeding speed is 20m / min;

[0054] S4, transverse stretch:

[0055] The green film sample obtained in S3 was placed in a drying room at a temperature of 120°C for 3 hours, and then stretched transversely by a transverse stretching machine. The temperatures of stretching zones 1 to 3 were 310°C, 320°C, and 330°C, respectively, the temperature of the sintering zone was 345°C, and the stretching ratio was 20, to obtain a finished PTFE film;

[0056] Lamination application:

[0057] The finished PTFE membrane obtained in S4 is laminated on the required filter material by hot pressing to obtain a coated filter material with oleophobic effect.

[0058] Example 3

[0059] S1, Preparation of ultra-microporous materials:

[0060] 3,3,5,5-tetramethyl-1H,1H-4,4-bipyrazole and NiSiF 6 6H 2O is reacted in a hydrothermal reactor at a molar ratio of 4:1 and under the catalysis of Pd to obtain a SiFSiX-18-Ni-α metal-organic framework; then, the SiFSiX-18-Ni-α is heated to 85°C under vacuum to cause a phase transformation of the material, increase the number of micropores, and obtain an ultra-microporous material;

[0061] S2, Preparation of PTFE blank membrane:

[0062] After PTFE resin, extrusion aid, cross-linking agent and ultra-microporous material (mass ratio of 100:32:5:7) are mixed evenly, placed in a drying room at a temperature of 58°C for 24 hours, and then the mixture is pre-pressed by a pre-pressing machine to obtain a rod-shaped blank, and then calendered by a calendering machine to obtain a PTFE blank film with a thickness of 270 μm and a width of 13 cm;

[0063] S3, PTFE film degreasing and longitudinal stretching:

[0064] The PTFE blank film obtained in S2 is degreased and longitudinally stretched in an oven to obtain a blank film sample; wherein the degreasing temperature is 190°C, the longitudinal stretching temperature is 220°C, the longitudinal stretching ratio is 7 times, and the blank film feeding speed is 20m / min;

[0065] S4, transverse stretch:

[0066] The green film sample obtained in S3 was placed in a drying room at a temperature of 120°C for 3 hours, and then stretched transversely by a transverse stretching machine. The temperatures of stretching zones 1 to 3 were 320°C, 330°C, and 340°C, respectively, the temperature of the sintering zone was 350°C, and the stretching ratio was 20, to obtain a finished PTFE film;

[0067] Lamination application:

[0068] The finished PTFE membrane obtained in S4 is laminated on the required filter material by hot pressing to obtain a coated filter material with oleophobic effect.

[0069] Comparative Example 1

[0070] S1, mix the PTFE and extrusion aid in a mass ratio of 100:32 through a mixer, and then place them in a drying room at a temperature of 58°C for 24 hours;

[0071] S2, degreasing and longitudinal stretching of PTFE blank film: the PTFE blank film obtained in S1 is degreased and longitudinally stretched in an oven to obtain a blank film sample, and the degreasing temperature is 190°C;

[0072] S3, placing the green film sample in a drying room at a temperature of 120°C for 3 hours, and then stretching it transversely through a transverse stretching machine. The temperatures of stretching zones 1 to 3 are 310°C, 320°C, and 330°C respectively, the temperature of the sintering zone is 345°C, and the stretching ratio is 20, to obtain a finished PTFE film.

[0073] Lamination application:

[0074] The obtained finished PTFE membrane is laminated on the required filter material by hot pressing to obtain a coated filter material with oleophobic effect.

[0075] Experimental testing

[0076] The coated filter materials prepared in each embodiment and comparative example were made into filter bags and applied to waste incineration power plants. The carbon dioxide concentration in the flue gas and the dust emission concentration were monitored and recorded in real time through the online detection system (CEMS) of the power plant. The test results are shown in Table 1:

[0077] Table 1 Filter bag performance test results

[0078]

[0079] It can be seen from Table 1 that the carbon dioxide adsorption effect of the filter bag obtained in the embodiment is higher than that of the comparative example, and the effect of the filter bag obtained by the process of embodiment 2 is the best. This is mainly because the microporous material in the PTFE microporous membrane (obtained by heating SiFSiX-18-Ni-α) will not block the pores in the PTFE microporous membrane on the one hand, and can remove / absorb carbon dioxide in the flue gas through catalytic reaction on the other hand.

[0080] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0081] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements all fall within the scope of the present invention to be protected.

Claims

1. A method for preparing a multifunctional PTFE membrane capable of adsorbing carbon dioxide gas, characterized in that: The following steps are involved: 3,3,5,5-tetramethyl-1H,1H-4,4-bipyrazole was mixed with NiSiF6·6H2O and reacted under Pd catalysis to obtain SiFSiX-18-Ni-α, and then SiFSiX-18-Ni-α was heated under vacuum to obtain an ultra-microporous material; After the PTFE resin, extrusion aid, cross-linking agent and ultra-microporous material are uniformly mixed, the mixture is placed in a drying room for standing, and then pre-pressed and calendered to obtain a PTFE blank film; Degreasing and longitudinally stretching the PTFE blank film to obtain a blank film sample; The green film sample is placed in a drying room to stand, and then stretched transversely to obtain a PTFE film.

2. The method for preparing a multifunctional PTFE membrane capable of adsorbing carbon dioxide gas according to claim 1, characterized in that: The molar ratio of 3,3,5,5-tetramethyl-1H,1H-4,4-bipyrazole to NiSiF6·6H2O is (3.5-4):

1.

3. The method for preparing a multifunctional PTFE membrane capable of adsorbing carbon dioxide gas according to claim 1, characterized in that: The heating temperature of SiFSiX-18-Ni-α is 85℃.

4. The method for preparing a multifunctional PTFE membrane capable of adsorbing carbon dioxide gas according to claim 1, characterized in that: The mass ratio of PTFE resin, extrusion aid, cross-linking agent and ultra-microporous material is 100:32:(4-5):(5-7).

5. The method for preparing a multifunctional PTFE membrane capable of adsorbing carbon dioxide gas according to claim 1, characterized in that: The degreasing temperature is 190°C and the longitudinal drawing temperature is 220°C.

6. The method for preparing a multifunctional PTFE membrane capable of adsorbing carbon dioxide gas according to claim 1, characterized in that: The temperatures of the stretching zones 1 to 3 of the transverse stretching are 300-320°C, 310-330°C, and 320-34°C respectively, the temperature of the sintering zone is 340-350°C, and the stretching ratio is 20.

7. The method for preparing a multifunctional PTFE membrane capable of adsorbing carbon dioxide gas according to claim 1, characterized in that: After the PTFE resin, extrusion aid, cross-linking agent and ultra-microporous material are evenly mixed, they are placed in a drying room at a temperature of 55-60°C for more than 24 hours; The temperature of the drying room where the blank film sample is placed is 120° C. for 2-4 hours.

8. A multifunctional PTFE membrane capable of adsorbing carbon dioxide gas, characterized in that: The multifunctional PTFE membrane capable of adsorbing carbon dioxide gas is prepared using the method for preparing the membrane according to any one of claims 1 to 7.

9. Use of the multifunctional PTFE membrane capable of adsorbing carbon dioxide gas as claimed in claim 8 in the preparation of membrane filter material.

10. A filter bag comprising a membrane-coated filter material, characterized in that: The multifunctional PTFE membrane capable of adsorbing carbon dioxide gas as claimed in claim 8 is adhered to the membrane filter material.

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