Adsorbent material for purification of electronic grade octafluorocyclobutane, preparation method and application

Abstract

The present application relates to a kind of for electronic grade octafluorocyclobutane purification adsorbing material, preparation method and application, the preparation method includes the following steps: (1) first ligand, second ligand, transition metal salt, water and multi-walled carbon nanotube are mixed, impregnation, first drying, obtain solid material;Third ligand and organic solvent are mixed, to obtain organic solution;(2) the solid material and the organic solution are mixed, impregnation, second drying is carried out after, under the protection of inert atmosphere, to obtain the adsorbing material.The obtained adsorbing material can remove fluorocarbon impurities in industrial grade 3N purity octafluorocyclobutane raw gas, so that it can be more simply purified into 6N grade product, reaches the requirement of electronic grade.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of purification, and relates to an adsorption material, in particular to an adsorption material for purifying electronic-grade octafluorocyclobutane, a preparation method and application. BACKGROUND

[0002] Octafluorocyclobutane, also known as perfluorocyclobutane, is a kind of special gas with stable chemical properties, good insulation, no toxicity and zero ODP value. The application range of octafluorocyclobutane is very wide. In recent years, it has been widely used as a refrigerant. In addition, it is also commonly used as a gas insulation medium, a solvent, a spray, a foaming agent, a large-scale circuit etchant, a heat pump working fluid and a raw material for producing C2F4 and C3F6 monomers. High-purity octafluorocyclobutane is used for ultra-large-scale integrated circuit etchant and cleaning agent. With the rapid development of chemical and electronic industries, the demand for octafluorocyclobutane is increasing year by year, and its preparation process and purification process have attracted more attention, and the application prospect is very broad.

[0003] There are various preparation methods for octafluorocyclobutane, such as tetrafluorocyclobutane electrochemical fluorination method, tetrafluoroethylene cracking method, fluorochlorocarbon cracking or co-cracking method. Among them, the tetrafluoroethylene cracking method is the main method used at present. However, when producing hexafluoropropane by the tetrafluoroethylene cracking method, octafluorocyclobutane is collected as a by-product. The main impurities include N2, O2, CO2, CO, H2O and fluorocarbon compounds (CF2=CF2, CF3CF=CFCF3, CF3CF=CF2). The purity of the obtained octafluorocyclobutane is only 99.9%, which cannot meet the requirements of the semiconductor industry for the purity of octafluorocyclobutane. SUMMARY

[0004] In view of the deficiencies of the prior art, the purpose of the present application is to provide an adsorption material for purifying electronic-grade octafluorocyclobutane, a preparation method and application. The adsorption material can remove fluorocarbon impurities in industrial-grade 3N-purity octafluorocyclobutane raw gas, so that it can be more simply purified into 6N-grade product, meeting the requirements of electronic grade.

[0005] To achieve the purpose of the present application, the following technical solutions are adopted:

[0006] In a first aspect, the present application provides a preparation method of an adsorption material for purifying electronic-grade octafluorocyclobutane, which comprises the following steps:

[0007] (1) mixing a first ligand, a second ligand, a transition metal salt, water and a multi-walled carbon nanotube, impregnating and first drying to obtain a solid material; mixing a third ligand with an organic solvent to obtain an organic solution;

[0008] (2) The solid material is mixed with the organic solution, impregnated, dried a second time, and then calcined under an inert atmosphere to obtain the adsorbent material;

[0009] The first ligand includes any one or a combination of at least two of ammonium carbonate, urea, ammonium sulfate, or ammonium nitrate;

[0010] The second ligand includes any one or a combination of at least two of the following: ammonium molybdate, ammonium chloride, ammonium phosphate, ammonium purpurate, ammonium manganese sulfate, ammonium chromate, or ammonium fluorotitanate;

[0011] The third ligand includes any one or a combination of at least two of phthalic anhydride, succinic anhydride, maleic anhydride, tetrahydrofuran-2,5-dione, 1,3-dihydrobenzofuran-1,3-dione, or 1,3-dihydroisobenzofuran-1,3-dione.

[0012] The adsorbent obtained by the preparation method of this invention can be used as an adsorbent for purifying industrial-grade 3N purity octafluorocyclobutane feed gas. The removal rate of fluorocarbon impurities in it can reach more than 98%, and the fluorocarbon impurities in the adsorbed octafluorocyclobutane are less than 100 ppm, which greatly reduces the difficulty of subsequent purification.

[0013] In some embodiments, the first ligand comprises urea and / or ammonium carbonate.

[0014] In some embodiments, the second ligand comprises a combination of ammonium molybdate and ammonium chloride.

[0015] In some embodiments, the third ligand comprises phthalic acid glycoside and / or maleic anhydride.

[0016] In some embodiments, the transition metal salt includes any one or a combination of at least two of ferrous sulfate, ferric sulfate, ferric chloride, ferric nitrate, copper sulfate, copper chloride, copper nitrate, nickel sulfate, nickel nitrate, nickel chloride, zinc sulfate, zinc nitrate, or zinc chloride.

[0017] In some embodiments, the transition metal salt includes ferric chloride and / or zinc chloride.

[0018] In some embodiments, the mass ratio of the first ligand to the second ligand is 1:0.1 to 1:10, preferably 1:0.1 to 1:0.3.

[0019] In some embodiments, the mass ratio of the first ligand to the transition metal salt is 1:0.1 to 1:10, preferably 1:0.1 to 1:0.3.

[0020] In some embodiments, the mass ratio of the first ligand to the water is 1:2 to 1:100, preferably 1:10 to 1:50.

[0021] In some embodiments, the mass ratio of the multi-walled carbon nanotubes to the water is 1:1 to 1:50, preferably 1:2 to 1:10.

[0022] In some embodiments, the mixing method in step (1) includes: dissolving the first ligand, the second ligand, and the transition metal salt in the water, then stirring and impregnating them with the multi-walled carbon nanotubes, followed by a first drying process to obtain a solid material.

[0023] In some embodiments, the temperature of the first drying is 20°C to 250°C, preferably 80°C to 150°C.

[0024] In some embodiments, the organic solvent includes any one or a combination of at least two of methanol, ethanol, propanol, isopropanol, acetone, tetrahydrofuran, or N,N-dimethylformamide.

[0025] In some embodiments, the mass ratio of the third ligand to the organic solvent is 1:1 to 1:100, preferably 1:5 to 1:10.

[0026] In some embodiments, the temperature of the second drying is 20°C to 250°C, preferably 100°C to 120°C.

[0027] In some embodiments, the calcination temperature is 100℃~1000℃, preferably 200℃~400℃.

[0028] In a second aspect, the present invention provides an adsorbent material for the purification of electronic-grade octafluorocyclobutane, wherein the adsorbent material is prepared by the preparation method described in the first aspect.

[0029] Thirdly, the present invention provides an application of the adsorbent material described in the second aspect for the purification of electronic-grade octafluorocyclobutane, the application comprising:

[0030] The adsorption material is packed into the adsorption column, and octafluorocyclobutane feed gas is introduced to adsorb fluorocarbon impurities in the octafluorocyclobutane feed gas.

[0031] In some embodiments, the space velocity of the octafluorocyclobutane feed gas is 0.01 s. -1 ~100s -1 Preferably 1s -1 ~20s -1 .

[0032] In some embodiments, the inlet temperature of the octafluorocyclobutane feed gas is -50°C to 150°C, preferably -30°C to 30°C.

[0033] In some embodiments, the inlet pressure of the octafluorocyclobutane feed gas is 0 MPa to 2 MPa, preferably 0 MPa to 0.5 MPa.

[0034] The numerical range described in this invention includes not only the point values ​​listed above, but also any point values ​​within the numerical ranges not listed above. Due to space limitations and for the sake of brevity, this invention will not exhaustively list all the specific point values ​​included in the range.

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] The adsorption material provided by this invention can be used as an adsorption material for purifying industrial-grade 3N purity octafluorocyclobutane feed gas. It can remove fluorocarbon impurities in the gas at a rate of over 98%. The fluorocarbon impurities in the adsorbed octafluorocyclobutane are less than 100 ppm, which greatly reduces the difficulty of subsequent purification. Detailed Implementation

[0037] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0038] The "range" disclosed in this invention can be defined in the form of a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, which define the boundaries of the specific range. This type of range definition can include or exclude endpoints; any endpoint can be independently included or excluded, and they can be arbitrarily combined, meaning any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60~120 and 80~110 are listed for specific parameters, it is understood that ranges of 60~110 and 80~120 are also expected. Furthermore, if minimum range values ​​1 and 2 are listed, and maximum range values ​​3, 4, and 5 are also listed, then the following ranges are all expected: 1~3, 1~4, 1~5, 2~3, 2~4, and 2~5. In this invention, unless otherwise stated, the numerical range "a~b" represents a shortened representation of any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "0~5" indicates that all real numbers between "0" and "5" have been listed in this article; "0~5" is simply a shortened representation of these numerical combinations. Furthermore, when a parameter is described as an integer ≥2, it is equivalent to listing integers such as 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc. For instance, when a parameter is described as an integer selected from "2~10", it is equivalent to listing the integers 2, 3, 4, 5, 6, 7, 8, 9, and 10.

[0039] In this invention, "a combination of at least two" refers to a quantity greater than or equal to two, unless otherwise specified. For example, "any combination of one or at least two" means one or more or more items. It can be understood that when referring to "a combination of at least two," it refers to any suitable combination of multiple items, that is, a combination of "at least two" items carried out in a manner that does not conflict with and enables the implementation of this invention.

[0040] Unless otherwise specified, all embodiments and optional embodiments of the present invention can be combined with each other to form new technical solutions.

[0041] The term "embodiment" as used in this invention means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment or implementation of the invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this invention can be combined with other embodiments.

[0042] Those skilled in the art will understand that the order in which the steps are written in the methods of the various embodiments does not imply a strict execution order. The detailed execution order of each step should be determined by its function and possible internal logic. Unless otherwise specified, all steps of the present invention may be performed sequentially or randomly, but are preferably performed sequentially. For example, if the method includes steps (a) and (b), it means that the method may include steps (a) and (b) performed sequentially, or it may include steps (b) and (a) performed sequentially. For example, the method may also include step (c), meaning that step (c) can be added to the method in any order. For example, the method may include steps (a), (b), and (c), or it may include steps (a), (c), and (b), or it may include steps (c), (a), and (b), etc.

[0043] In this invention, open-ended technical features or solutions described using terms such as "comprising" do not exclude additional members beyond those listed unless otherwise specified. They can be considered as providing both closed-ended features or solutions comprised of the listed members and open-ended features or solutions that include additional members beyond the listed members. For example, A includes a1, a2, and a3. Unless otherwise specified, it may also include other members or exclude additional members. This can be considered as providing both technical features or solutions where "A is composed of a1, a2, and a3" or "A is selected from a1, a2, and a3," and technical features or solutions where "A includes not only a1, a2, and a3, but also other members."

[0044] In this invention, unless otherwise specified, the features or solutions corresponding to "and / or" include any one of two or more of the related listed items, as well as any and all combinations of the related listed items. These arbitrary and all combinations include any two related listed items, any more related listed items, or a combination of all related listed items. For example, "A and / or B" represents a group consisting of A, B, and "a combination of A and B". "Containing A and / or B" can mean "containing A, containing B, and containing A and B", or "containing A, containing B, or containing A and B", and can be appropriately understood according to the context.

[0045] In this invention, the terms "first aspect," "second aspect," "third aspect," "fourth aspect," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or quantity, nor should they be construed as implicitly indicating the importance or quantity of the indicated technical features. Moreover, "first," "second," "third," "fourth," etc., serve only as a non-exhaustive enumeration and should be understood not to constitute a closed limitation on the quantity.

[0046] In this invention, "optional" means that something is optional, that is, it refers to any one of the two parallel solutions of "having" or "not having". If there are multiple "optional" options in a technical solution, unless otherwise specified, and there are no contradictions or mutual constraints, then each "optional" option is independent.

[0047] In this invention, "room temperature" generally refers to 4℃~35℃, and can refer to 20℃±5℃. In some embodiments of this invention, room temperature refers to 20℃~30℃.

[0048] During the preparation of octafluorocyclobutane, the breaking of carbon-carbon bonds leads to the generation of a large number of fragments. Therefore, the crude octafluorocyclobutane gas contains fluorocarbons containing elements such as C, F, Cl, and H. These impurities can lead to high defect rates in integrated circuits during etching and cleaning, affecting the performance and yield of electronic products. At present, the purification methods for octafluorocyclobutane include distillation, adsorption separation, chemical conversion, and membrane separation.

[0049] Distillation is a separation method that utilizes the differences in boiling points of components in a gas mixture to purify them through temperature changes. It can separate most organofluorocarbon compounds, yielding high-purity octafluorocyclobutane. However, octafluorocyclobutane is a low-pressure liquefied gas with a saturated vapor pressure of only 0.2 MPa at room temperature and a relatively high liquefaction temperature, making it difficult to obtain octafluorocyclobutane with a purity reaching 6N and meeting electronic grade requirements. Therefore, in actual industrial production, a combination of several distillation methods, such as azeotropic distillation and extractive distillation, is often used.

[0050] Adsorption separation utilizes the difference in binding forces between adsorbate and adsorbent surface molecules to achieve separation and purification. Compared to distillation, adsorption separation can selectively adsorb fluorocarbon impurities in octafluorocyclobutane. Furthermore, adsorption separation is inexpensive, easy to operate, and operates under mild conditions, making it a widely used separation and purification method. Common adsorbents used in adsorption separation include activated carbon, metal oxides, and molecular sieves. However, octafluorocyclobutane contains a wide variety of azeotropic impurities, requiring the development of multiple types of adsorbents to meet the requirements for different impurities, which significantly increases the difficulty of purification.

[0051] Chemical conversion mainly involves using chemical reactions to transform difficult-to-separate impurities in octafluorocyclobutane into easily separable impurities. However, it can only remove one or a few specific impurities, the process is complex, and it may cause octafluorocyclobutane to react, thus reducing its yield.

[0052] Current membrane separation methods can only separate impurities with a diameter significantly different from that of octafluorocyclobutane molecules, and cannot remove impurities down to 10⁻⁶. -6 level.

[0053] An embodiment of the present invention provides a method for preparing an adsorbent material for the purification of electronic-grade octafluorocyclobutane, the preparation method comprising the following steps:

[0054] (1) Mix the first ligand, the second ligand, the transition metal salt, water and multi-walled carbon nanotubes, impregnate and dry to obtain a solid material; mix the third ligand with an organic solvent to obtain an organic solution;

[0055] (2) The solid material is mixed with the organic solution, impregnated, dried a second time, and then calcined under an inert atmosphere to obtain the adsorbent material;

[0056] The first ligand includes any one or a combination of at least two of ammonium carbonate, urea, ammonium sulfate, or ammonium nitrate;

[0057] The second ligand includes any one or a combination of at least two of the following: ammonium molybdate, ammonium chloride, ammonium phosphate, ammonium purpurate, ammonium manganese sulfate, ammonium chromate, or ammonium fluorotitanate;

[0058] The third ligand includes any one or a combination of at least two of phthalic anhydride, succinic anhydride, maleic anhydride, tetrahydrofuran-2,5-dione, 1,3-dihydrobenzofuran-1,3-dione, or 1,3-dihydroisobenzofuran-1,3-dione.

[0059] The adsorbent obtained by the preparation method of this invention can be used as an adsorbent for purifying industrial-grade 3N purity octafluorocyclobutane feed gas. The removal rate of fluorocarbon impurities in it can reach more than 98%, and the fluorocarbon impurities in the adsorbed octafluorocyclobutane are less than 100 ppm, which greatly reduces the difficulty of subsequent purification.

[0060] Specifically, the first and second ligands form multi-coordinated salts with the transition metal salt during preparation, resulting in stronger binding forces with multi-walled carbon nanotubes during impregnation. The presence of the ligands also ensures a more uniform distribution of transition metal ions on the multi-walled carbon nanotubes, reducing the likelihood of clusters or large particles. The third ligand exhibits even stronger interactions with the metal ions, further enhancing the interaction between the transition metal ions and the multi-walled carbon nanotubes and improving the dispersion of metal ions on the support surface. During calcination, the first and second ligands leave the transition metal ions due to temperature variations, exposing sufficient coordination space on the transition metal ion surface, thus allowing the adsorbent material to effectively perform its adsorption function. The transition metal in the adsorbent material, acting as the main active site, forms coordination bonds with fluorine atoms in fluorocarbon molecules, not only enhancing adsorption strength but also activating the CF bonds in the fluorocarbon molecules, reducing the desorption probability, and achieving deep removal of fluorocarbon impurities. Multi-walled carbon nanotubes (MWCNTs) serve as a carrier, enabling π-π conjugation with the double bonds of fluorocarbon molecules. This promotes the transfer of electrons from fluorocarbon molecules to the carbon nanotubes, forming a charge-transfer complex. This electron transfer polarizes the fluorocarbon molecules, enhancing their coordination ability with MOF metal nodes. Therefore, the preparation method provided by this invention achieves highly efficient and specific adsorption of fluorocarbon impurities through the synergistic effect of the first ligand, second ligand, third ligand, transition metal salt, and carbon nanotubes.

[0061] Multi-walled carbon nanotubes (MWCNTs) are typically composed of multiple nested concentric cylindrical graphene layers, bonded together by van der Waals forces to form a rigid framework structure. During calcination, the multilayered structure of MWCNTs effectively disperses stress, preventing structural collapse and thus maintaining structural integrity.

[0062] In some embodiments, the first ligand comprises urea and / or ammonium carbonate.

[0063] In some embodiments, the second ligand comprises a combination of ammonium molybdate and ammonium chloride.

[0064] In some embodiments, the third ligand comprises phthalic acid glycoside and / or maleic anhydride.

[0065] In some embodiments, the transition metal salt includes any one or a combination of at least two of ferrous sulfate, ferric sulfate, ferric chloride, ferric nitrate, copper sulfate, copper chloride, copper nitrate, nickel sulfate, nickel nitrate, nickel chloride, zinc sulfate, zinc nitrate, or zinc chloride, preferably ferric chloride and / or zinc chloride.

[0066] In some embodiments, the mass ratio of the first ligand to the second ligand is 1:0.1 to 1:10, for example, it can be 1:0.1, 1:0.2, 1:0.3, 1:0.5, 1:1, 1:2, 1:3, 1:5, 1:6, 1:8 or 1:10, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable, preferably 1:0.1 to 1:0.3.

[0067] In some embodiments, the mass ratio of the first ligand to the transition metal salt is 1:0.1 to 1:10, for example, it can be 1:0.1, 1:0.2, 1:0.3, 1:0.5, 1:1, 1:2, 1:3, 1:5, 1:6, 1:8 or 1:10, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable, preferably 1:0.1 to 1:0.3.

[0068] In some embodiments, the mass ratio of the first ligand to the water is 1:2 to 1:100, for example, it can be 1:2, 1:5, 1:10, 1:20, 1:30, 1:40, 1:50, 1:60, 1:80 or 1:100, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable, preferably 1:10 to 1:50.

[0069] In some embodiments, the mass ratio of the multi-walled carbon nanotubes to the water is 1:1 to 1:50, for example, it can be 1:1, 1:2, 1:5, 1:10, 1:15, 1:20, 1:30, 1:40 or 1:50, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable, preferably 1:2 to 1:10.

[0070] In some embodiments, the mixing method in step (1) includes: dissolving the first ligand, the second ligand, and the transition metal salt in the water, then stirring and mixing with the multi-walled carbon nanotubes for impregnation, followed by a first drying to obtain a solid material.

[0071] In some embodiments, the temperature of the first drying is 20°C to 250°C, for example, it can be 20°C, 50°C, 80°C, 100°C, 120°C, 150°C, 180°C, 200°C, 240°C or 250°C, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable, preferably 80°C to 150°C.

[0072] In some embodiments, the organic solvent includes any one or a combination of at least two of methanol, ethanol, propanol, isopropanol, acetone, tetrahydrofuran, or N,N-dimethylformamide (DMF). Typical but non-limiting combinations include combinations of methanol and ethanol, propanol and isopropanol, acetone, tetrahydrofuran, and DMF, methanol, ethanol, propanol, and isopropanol, or methanol, ethanol, propanol, isopropanol, acetone, tetrahydrofuran, and DMF.

[0073] In some embodiments, the mass ratio of the third ligand to the organic solvent is 1:1 to 1:100, for example, it can be 1:1, 1:5, 1:8, 1:10, 1:20, 1:30, 1:50, 1:60, 1:80 or 1:100, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable, preferably 1:5 to 1:10.

[0074] In some embodiments, the temperature of the second drying is 20°C to 250°C, for example, it can be 20°C, 50°C, 80°C, 100°C, 110°C, 120°C, 150°C, 200°C or 250°C, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable, preferably 100°C to 120°C.

[0075] In some embodiments, the roasting temperature is 100℃~1000℃, for example, it can be 100℃, 200℃, 300℃, 400℃, 500℃, 600℃, 800℃ or 1000℃, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable, preferably 200℃~400℃.

[0076] An embodiment of the present invention provides an adsorbent material for the purification of electronic-grade octafluorocyclobutane, wherein the adsorbent material is prepared by the preparation method described in any embodiment.

[0077] An embodiment of the present invention provides an application of the adsorbent material described in any embodiment for the purification of electronic-grade octafluorocyclobutane, the application including:

[0078] The adsorption material is packed into the adsorption column, and octafluorocyclobutane feed gas is introduced to adsorb fluorocarbon impurities in the octafluorocyclobutane feed gas.

[0079] In some embodiments, the space velocity of the octafluorocyclobutane feed gas is 0.01 s. -1 ~100s -1 For example, it could be 0.01s -1 0.1s -1 1s -1 3s -1 5s -1 10s-1 15s -1 20s -1 40s -1 50s -1 60s -1 80s -1 Or 100s -1 However, it is not limited to the listed values; other unlisted values ​​within the range are also applicable, with 1s being the preferred value. -1 ~20s -1 .

[0080] In some embodiments, the inlet temperature of the octafluorocyclobutane feed gas is -50°C to 150°C, for example, it can be -50°C, -30°C, 0°C, 10°C, 20°C, 30°C, 50°C, 80°C, 100°C, 120°C or 150°C, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable, preferably -30°C to 30°C.

[0081] In some embodiments, the inlet pressure of the octafluorocyclobutane feed gas is 0 MPa to 2 MPa, for example, it can be 0 MPa, 0.1 MPa, 0.2 MPa, 0.3 MPa, 0.4 MPa, 0.5 MPa, 1 MPa, 1.5 MPa or 2 MPa, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable, preferably 0 MPa to 0.5 MPa.

[0082] Example 1

[0083] This embodiment provides a method for preparing an adsorbent material, the method comprising the following steps:

[0084] (1) The first ligand (ammonium carbonate), the second ligand (ammonium molybdate and ammonium chloride in a molar ratio of 1:1), and the transition metal salt (ferric chloride) are dissolved in the deionized water, and then mixed and impregnated with multi-walled carbon nanotubes. The mixture is then dried at 100°C to obtain a solid material.

[0085] The mass ratio of the first ligand to the second ligand is 1:0.2, the mass ratio of the first ligand to the transition metal salt is 1:0.2, the mass ratio of the first ligand to deionized water is 1:30, and the mass ratio of multi-walled carbon nanotubes to deionized water is 1:5.

[0086] (2) The third ligand (phthalic anhydride) is mixed with an organic solvent (DMF) to obtain an organic solution;

[0087] The mass ratio of the third ligand to the organic solvent is 1:8;

[0088] (3) Mix the solid material with the organic solution, impregnate, perform a second drying at 110°C, and calcine at 300°C in a nitrogen atmosphere to obtain the adsorbent material.

[0089] Example 2

[0090] This embodiment provides a method for preparing an adsorbent material, the method comprising the following steps:

[0091] (1) The first ligand (urea), the second ligand (ammonium molybdate and ammonium chloride in a molar ratio of 1:1), and the transition metal salt (zinc chloride) are dissolved in the deionized water, and then mixed and impregnated with multi-walled carbon nanotubes. The mixture is then dried at 80°C to obtain a solid material.

[0092] The mass ratio of the first ligand to the second ligand is 1:0.1, the mass ratio of the first ligand to the transition metal salt is 1:0.1, the mass ratio of the first ligand to deionized water is 1:10, and the mass ratio of multi-walled carbon nanotubes to deionized water is 1:2.

[0093] (2) The third ligand (maleic anhydride) is mixed with an organic solvent (DMF) to obtain an organic solution;

[0094] The mass ratio of the third ligand to the organic solvent is 1:5;

[0095] (3) Mix the solid material with the organic solution, impregnate, perform a second drying at 100°C, and calcine at 200°C in a nitrogen atmosphere to obtain the adsorbent material.

[0096] Example 3

[0097] This embodiment provides a method for preparing an adsorbent material, the method comprising the following steps:

[0098] (1) The first ligand (ammonium carbonate), the second ligand (ammonium molybdate and ammonium chloride in a molar ratio of 1:1), and the transition metal salt (zinc chloride) are dissolved in the deionized water, and then mixed and impregnated with multi-walled carbon nanotubes. The mixture is then dried at 150°C to obtain a solid material.

[0099] The mass ratio of the first ligand to the second ligand is 1:0.3, the mass ratio of the first ligand to the transition metal salt is 1:0.3, the mass ratio of the first ligand to deionized water is 1:50, and the mass ratio of multi-walled carbon nanotubes to deionized water is 1:10.

[0100] (2) The third ligand (phthalic anhydride) is mixed with an organic solvent (DMF) to obtain an organic solution;

[0101] The mass ratio of the third ligand to the organic solvent is 1:10.

[0102] (3) Mix the solid material with the organic solution, impregnate, perform a second drying at 120°C, and calcine at 400°C in a nitrogen atmosphere to obtain the adsorbent material.

[0103] Example 4

[0104] This embodiment provides a method for preparing an adsorbent material, which is the same as in Example 1 except that the mass ratio of the first ligand to the second ligand is 1:10.

[0105] Example 5

[0106] This embodiment provides a method for preparing an adsorbent material, which is the same as in Example 1 except that the mass ratio of the first ligand to the transition metal salt is 1:10.

[0107] Example 6

[0108] This embodiment provides a method for preparing an adsorbent material, which is the same as in Example 1 except that the mass ratio of the first ligand to deionized water is 1:2.

[0109] Example 7

[0110] This embodiment provides a method for preparing an adsorbent material, which is the same as in Example 1 except that the mass ratio of the first ligand to deionized water is 1:100.

[0111] Example 8

[0112] This embodiment provides a method for preparing an adsorbent material, which is the same as in Example 1 except that the first drying temperature is 20°C.

[0113] Example 9

[0114] This embodiment provides a method for preparing an adsorbent material, which is the same as in Example 1 except that the first drying temperature is 250°C.

[0115] Example 10

[0116] This embodiment provides a method for preparing an adsorbent material, which is the same as in Example 1 except that the mass ratio of the third ligand to the organic solvent is 1:1.

[0117] Example 11

[0118] This embodiment provides a method for preparing an adsorbent material, which is the same as in Example 1 except that the mass ratio of the third ligand to the organic solvent is 1:100.

[0119] Example 12

[0120] This embodiment provides a method for preparing an adsorbent material, which is the same as in Example 1 except that the second drying temperature is 20°C.

[0121] Example 13

[0122] This embodiment provides a method for preparing an adsorbent material, which is the same as in Example 1 except that the second drying temperature is 250°C.

[0123] Example 14

[0124] This embodiment provides a method for preparing an adsorbent material, which is the same as in Example 1 except that the calcination temperature is 100°C.

[0125] Example 15

[0126] This embodiment provides a method for preparing an adsorbent material, which is the same as in Example 1 except that the calcination temperature is 1000℃.

[0127] Performance Characterization

[0128] The adsorbent material obtained in the above embodiments was packed into an adsorption column, and octafluorocyclobutane feed gas was introduced to adsorb fluorocarbon impurities in the octafluorocyclobutane feed gas. The space velocity of the octafluorocyclobutane feed gas was 10 s⁻¹. -1 The intake air temperature is 10℃ and the intake air pressure is 0.3MPa.

[0129] The removal rate of fluorocarbon impurities and the content of fluorocarbon impurities in the resulting gas were determined, and the results are shown in Table 1.

[0130] The purity of the octafluorocyclobutane feed gas is 99.9%.

[0131] Table 1

[0132]

[0133] In summary, the adsorption material provided by this invention can be used as an adsorption material for purifying industrial-grade 3N purity octafluorocyclobutane feed gas, and the removal rate of fluorocarbon impurities in it can reach more than 98%. The fluorocarbon impurities in the adsorbed octafluorocyclobutane are less than 100 ppm, which greatly reduces the difficulty of subsequent purification.

[0134] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A method for preparing an adsorbent material for the purification of electronic-grade octafluorocyclobutane, characterized in that, The preparation method includes the following steps: (1) Mix the first ligand, the second ligand, the transition metal salt, water and multi-walled carbon nanotubes, impregnate and dry to obtain a solid material; mix the third ligand with an organic solvent to obtain an organic solution; The transition metal salts include any one or a combination of at least two of the following: ferrous sulfate, ferric sulfate, ferric chloride, ferric nitrate, copper sulfate, copper chloride, copper nitrate, nickel sulfate, nickel nitrate, nickel chloride, zinc sulfate, zinc nitrate, or zinc chloride. The mass ratio of the first ligand to the second ligand is 1:0.1 to 1:10; the mass ratio of the first ligand to the transition metal salt is 1:0.1 to 1:10; the mass ratio of the first ligand to the water is 1:2 to 1:100; and the mass ratio of the multi-walled carbon nanotube to the water is 1:1 to 1:

50. (2) The solid material is mixed with the organic solution, impregnated, dried a second time, and then calcined under an inert atmosphere to obtain the adsorbent material; The first ligand includes any one or a combination of at least two of ammonium carbonate, urea, ammonium sulfate, or ammonium nitrate; The second ligand includes any one or a combination of at least two of the following: ammonium molybdate, ammonium chloride, ammonium phosphate, ammonium purpurate, ammonium manganese sulfate, ammonium chromate, or ammonium fluorotitanate; The third ligand includes any one or a combination of at least two of phthalic anhydride, succinic anhydride, maleic anhydride, tetrahydrofuran-2,5-dione, 1,3-dihydrobenzofuran-1,3-dione, or 1,3-dihydroisobenzofuran-1,3-dione.

2. The preparation method according to claim 1, characterized in that, The first ligand includes urea and / or ammonium carbonate; And / or, the second ligand comprises a combination of ammonium molybdate and ammonium chloride; And / or, the third ligand comprises phthalic anhydride and / or maleic anhydride.

3. The preparation method according to claim 1, characterized in that, The mixing method in step (1) includes: dissolving the first ligand, the second ligand, and the transition metal salt in the water, and then mixing and impregnating them with the multi-walled carbon nanotubes, followed by drying to obtain a solid material.

4. The preparation method according to claim 1, characterized in that, The temperature for the first drying process is 20℃~250℃.

5. The preparation method according to claim 1, characterized in that, The organic solvent includes any one or a combination of at least two of methanol, ethanol, propanol, isopropanol, acetone, tetrahydrofuran, or N,N-dimethylformamide.

6. The preparation method according to claim 1, characterized in that, The mass ratio of the third ligand to the organic solvent is 1:1 to 1:

100.

7. The preparation method according to any one of claims 1 to 6, characterized in that, The second drying temperature is 20℃~250℃; And / or, the calcination temperature is 100℃~1000℃.

8. An adsorbent material for the purification of electronic-grade octafluorocyclobutane, characterized in that, The adsorbent material is prepared by the preparation method according to any one of claims 1 to 7.

9. The application of the adsorbent material of claim 8 for the purification of electronic-grade octafluorocyclobutane, characterized in that, The applications include: The adsorption material is packed into the adsorption column, and octafluorocyclobutane feed gas is introduced to adsorb fluorocarbon impurities in the octafluorocyclobutane feed gas.

10. The application according to claim 9, characterized in that, The space velocity of the octafluorocyclobutane feed gas is 0.01 s. -1 ~100s -1 ; And / or, the inlet temperature of the octafluorocyclobutane feed gas is -50℃ to 150℃; And / or, the inlet pressure of the octafluorocyclobutane feed gas is 0MPa~2MPa.

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