Inactivation and regeneration method of alumina-based catalyst for catalytic decomposition of carbon tetrafluoride

Abstract

The invention provides an alumina-based catalyst inactivation and regeneration method for catalytic decomposition of carbon tetrafluoride, and relates to the technical field of catalyst inactivation and regeneration, and the method comprises the following steps: filling an alumina-based catalyst into a quartz tube, fixing the quartz tube in a reaction bin, pre-introducing carbon tetrafluoride and air into the reaction bin, heating the reaction bin after a gas path is stable, and carrying out deactivation and regeneration on the alumina-based catalyst; injecting water into the vaporizing chamber through an injection pump, heating the vaporizing chamber, and controlling the humidity of the reaction bin until the catalyst is inactivated; the method comprises the following steps: filling a quartz tube with an inactivated catalyst, fixing the quartz tube in a reaction bin, pre-introducing air into the reaction bin, heating the reaction bin after an air path is stable, injecting water into a vaporizing chamber through an injection pump, heating the vaporizing chamber, controlling the humidity of the reaction bin, and regenerating the inactivated aluminum oxide catalyst through a hydrothermal aging reaction. According to the invention, the fluorine poisoning of the alumina-based catalyst during catalytic decomposition of carbon tetrafluoride can be efficiently removed.

Description

Technical Field

[0001] The invention belongs to the technical field of catalyst deactivation and regeneration, and in particular relates to a deactivation and regeneration method for an alumina-based catalyst for catalytically decomposing carbon tetrafluoride. Background Art

[0002] Perfluorinated compounds (PFCs) are a class of highly stable and persistent organic compounds. Due to their unique chemical properties, such as heat resistance, solvent resistance, and chemical resistance, they are widely used in many industries. However, these characteristics also make PFCs difficult to degrade in the natural environment. They are a class of stable and potentially harmful chemicals to the environment. They exist in the atmosphere, water bodies, and soil for a long time, posing a potential threat to ecosystems and human health. In the context of increasing attention to environmental protection, the decomposition and treatment of perfluorinated compounds has become a difficult problem. Among them, carbon tetrafluoride (CF4) is the most common perfluorinated compound, which is often used in industries such as semiconductor manufacturing and aluminum smelting. However, it has attracted special attention due to its extremely strong greenhouse effect and a lifespan of up to 50,000 years in the atmosphere. At present, CF4 has been listed as an important greenhouse gas reduction in the Kyoto Protocol and the EU Carbon Border Act.

[0003] Thermal catalytic decomposition of CF4 is a common and effective treatment method that can convert CF4 into more environmentally friendly products. Alumina-based catalysts show good catalytic activity and stability in this process. However, as the reaction time proceeds, the catalyst is prone to adsorb impurities and reaction by-products during the catalytic process and gradually deactivates, resulting in fluorine poisoning and reduced catalytic efficiency. In order to ensure the catalytic efficiency, a large amount of catalyst is required for the catalytic decomposition of CF4, resulting in a waste of resources. Therefore, there is an urgent need for a method to regenerate and recycle the deactivated alumina-based catalyst. Summary of the invention

[0004] The purpose of the present invention is to provide a method for regenerating an alumina-based catalyst for catalytic decomposition of carbon tetrafluoride, so as to solve the problem of fluorine poisoning and deactivation of the alumina-based catalyst during long-term catalytic decomposition of CF4.

[0005] The technical solution adopted in the embodiment of the present invention is:

[0006] A method for regenerating an alumina-based catalyst for catalytically decomposing carbon tetrafluoride comprises the following steps:

[0007] S1, loading the alumina-based catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0008] S2, pre-introduce CF4 and air into the reaction chamber, and after the gas path is stable, heat the reaction chamber;

[0009] S3, injecting water into the vaporization chamber through an injection pump to heat the vaporization chamber, wherein the vaporization chamber is connected to the reaction chamber, controlling the humidity of the reaction chamber until the catalyst is deactivated, removing the deactivated catalyst and emptying the reaction chamber;

[0010] S4, loading the deactivated catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0011] S5. Pre-introduce air into the reaction chamber, and after the air path is stable, heat the reaction chamber;

[0012] S6. Inject water into the vaporization chamber through an injection pump to heat the vaporization chamber. The vaporization chamber is connected to the reaction chamber to control the humidity of the reaction chamber to hydrothermally age the inactivated alumina catalyst.

[0013] Furthermore, in step S1, the alumina-based catalyst includes one of a γ-Al2O3 catalyst, a Ni-γ-Al2O3 catalyst, a θ-Al2O3 catalyst or a Ga-θ-Al2O3 catalyst.

[0014] Furthermore, in step S2, the CF4 flow rate is 0.3-0.5 ml / min, the air flow rate is 31-33 ml / min, the reaction chamber is heated to 550-600°C, and the heating rate is 4-6°C min -1 .

[0015] Furthermore, in step S3, the vaporization chamber is heated to 150° C., and the humidity of the reaction chamber is controlled to be 5-15%.

[0016] Furthermore, in step S5, the air flow rate is 31-33 ml / min, the reaction chamber is heated to 530-620°C, and the heating rate is 4-6°C min -1 .

[0017] Furthermore, in step S6, the vaporization chamber is heated to 150° C., the humidity of the reaction chamber is controlled to be 3-19%, and the reaction time is 10-30 hours.

[0018] Furthermore, the temperature of the reaction chamber in step S5 is the same as the temperature of the reaction chamber in step S2.

[0019] Furthermore, the humidity of the reaction chamber in step S6 is the same as the humidity of the reaction chamber in step S3.

[0020] Furthermore, in step S2, the air flow rate is 32.9 ml / min, and the heating rate is 5°C min -1 .

[0021] Furthermore, in step S5, the air flow rate is 32.9 ml / min, and the heating rate is 5°C min -1 .

[0022] The beneficial effects of the embodiments of the present invention are:

[0023] (1) The present invention adopts an aging regeneration method to remove the byproducts generated by the alumina-based catalyst during the catalytic decomposition of CF4, which can achieve efficient regeneration of the activity of the alumina-based catalyst. The operation process is simple and efficient, so that the catalyst can be recycled and the waste of resources is avoided.

[0024] (2) The present invention can improve the catalytic efficiency of the catalyst by setting the temperature, humidity and aging time of the regeneration reaction, and can achieve the initial catalytic efficiency when the conditions of the catalytic decomposition of carbon tetrafluoride process and the regeneration reaction process are the same. In practical applications, a rapid catalytic-regeneration process can be achieved, which has high practical value. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0026] Figure 1 It is a schematic diagram of the structure of the reaction device of the present invention;

[0027] Figure 2 This is a schematic diagram of the process of catalytic decomposition of CF4 by the catalyst of the present invention;

[0028] Figure 3 It is a schematic diagram of the catalyst regeneration process of the present invention;

[0029] Figure 4 TEM images of the γ-Al2O3 catalyst in Example 28 of the present invention, FIG. (a) is the initial catalyst, FIG. (b) is the catalyst after deactivation and regeneration, and FIG. (c) is the element distribution on the surface of the catalyst after deactivation and regeneration;

[0030] Figure 5 This is the TEM image of the Ni-γ-Al2O3 catalyst of Example 29 of the present invention, Figure (a) is the initial catalyst, Figure (b) is the catalyst after deactivation and regeneration, and Figure (c) is the element distribution on the surface of the catalyst after deactivation and regeneration.

[0031] In the attached drawings, 1 is a vaporization chamber, 2 is a reaction chamber, 3 is an injection pump, 4 is an exhaust gas inspection device, 5 is an exhaust gas treatment device, 6 is a switch, 7 is a flow meter, 8 is a stop valve, and 9 is a quartz tube. DETAILED DESCRIPTION

[0032] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments 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.

[0033] like Figure 1 As shown, it is a schematic diagram of the structure of the reaction device of the present invention. The lower end of the vaporization chamber 1 is connected to the quartz tube 9, and the quartz tube 9 is fixed in the reaction chamber 2. The injection pump 3 is connected to the right end of the vaporization chamber 1 to pump water in. CF4 and air are each connected to the left end of the vaporization chamber 1 through a gas pipeline. A switch 6, a flow meter 7 and a stop valve 8 are provided on the gas pipeline and are connected in sequence. The lower end opening of the quartz tube 9 is connected to the exhaust gas treatment device 5, and the exhaust gas treatment device 5 is connected to the exhaust gas inspection device 4.

[0034] Example 1

[0035] A method for regenerating a deactivated γ-Al2O3 catalyst for catalytically decomposing carbon tetrafluoride comprises the following steps:

[0036] S1, filling 2g of γ-Al2O3 catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0037] S2. Pre-introduce CF4 and air into the reaction chamber, with a CF4 flow rate of 0.3 ml / min and an air flow rate of 31 ml / min. After the gas path is stable, heat the reaction chamber to 550°C at a heating rate of 4°C / min. -1 ;

[0038] S3, injecting water into the vaporization chamber through an injection pump, heating the vaporization chamber to 150° C., the vaporization chamber is connected to the reaction chamber, and the humidity of the reaction chamber is controlled to be 5% until the catalyst is deactivated, taking out the deactivated catalyst and emptying the reaction chamber;

[0039] S4, loading the deactivated catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0040] S5. Pre-introduce air into the reaction chamber at a flow rate of 31 ml / min. After the air path is stable, heat the reaction chamber to 530°C at a heating rate of 4°C / min. -1 ;

[0041] S6. Inject water into the vaporization chamber through an injection pump to heat the vaporization chamber. The vaporization chamber is connected to the reaction chamber. The humidity of the reaction chamber is controlled to be 5%. The alumina catalyst is deactivated by hydrothermal aging. The reaction time is 20 hours.

[0042] The process of catalytic decomposition of CF4 by the catalyst is as follows Figure 2 As shown;

[0043] The catalyst regeneration process is as follows: Figure 3 As shown;

[0044] Example 2

[0045] A method for regenerating a deactivated γ-Al2O3 catalyst for catalytically decomposing carbon tetrafluoride comprises the following steps:

[0046] S1, filling 2g of γ-Al2O3 catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0047] S2. Pre-introduce CF4 and air into the reaction chamber, with a CF4 flow rate of 0.4 ml / min and an air flow rate of 32 ml / min. After the gas path is stable, heat the reaction chamber to 550°C at a heating rate of 5°C / min. -1 ;

[0048] S3, injecting water into the vaporization chamber through an injection pump, heating the vaporization chamber to 150° C., the vaporization chamber is connected to the reaction chamber, and the humidity of the reaction chamber is controlled to be 5% until the catalyst is deactivated, taking out the deactivated catalyst and emptying the reaction chamber;

[0049] S4, loading the deactivated catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0050] S5. Pre-introduce air into the reaction chamber at a flow rate of 32 ml / min. After the air path is stable, heat the reaction chamber to 550°C at a heating rate of 6°C / min. -1 ;

[0051] S6. Inject water into the vaporization chamber through an injection pump to heat the vaporization chamber. The vaporization chamber is connected to the reaction chamber. The humidity of the reaction chamber is controlled to be 5%. The alumina catalyst is deactivated by hydrothermal aging. The reaction time is 20 hours.

[0052] Example 3

[0053] A method for regenerating a deactivated γ-Al2O3 catalyst for catalytically decomposing carbon tetrafluoride comprises the following steps:

[0054] S1, filling 2g of γ-Al2O3 catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0055] S2. Pre-introduce CF4 and air into the reaction chamber, with a CF4 flow rate of 0.5 ml / min and an air flow rate of 33 ml / min. After the gas path is stable, heat the reaction chamber to 550°C at a heating rate of 6°C / min. -1 ;

[0056] S3, injecting water into the vaporization chamber through an injection pump, heating the vaporization chamber to 150° C., the vaporization chamber is connected to the reaction chamber, and the humidity of the reaction chamber is controlled to be 5% until the catalyst is deactivated, taking out the deactivated catalyst and emptying the reaction chamber;

[0057] S4, loading the deactivated catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0058] S5. Pre-introduce air into the reaction chamber at a flow rate of 33 ml / min. After the air path is stable, heat the reaction chamber to 570°C at a heating rate of 6°C / min. -1 ;

[0059] S6. Inject water into the vaporization chamber through an injection pump to heat the vaporization chamber. The vaporization chamber is connected to the reaction chamber. The humidity of the reaction chamber is controlled to be 5%. The alumina catalyst is deactivated by hydrothermal aging. The reaction time is 20 hours.

[0060] Example 4

[0061] A method for regenerating a deactivated γ-Al2O3 catalyst for catalytically decomposing carbon tetrafluoride comprises the following steps:

[0062] S1, filling 2g of γ-Al2O3 catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0063] S2. Pre-introduce CF4 and air into the reaction chamber, with a CF4 flow rate of 0.4 ml / min and an air flow rate of 32.9 ml / min. After the gas path is stable, heat the reaction chamber to 575°C at a heating rate of 5°C / min. -1 ;

[0064] S3, injecting water into the vaporization chamber through an injection pump, heating the vaporization chamber to 150° C., the vaporization chamber is connected to the reaction chamber, and the humidity of the reaction chamber is controlled to be 5% until the catalyst is deactivated, taking out the deactivated catalyst and emptying the reaction chamber;

[0065] S4, loading the deactivated catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0066] S5. Pre-introduce air into the reaction chamber at an air flow rate of 32.9 ml / min. After the air path is stable, heat the reaction chamber to 555°C at a heating rate of 5°C / min. -1 ;

[0067] S6. Inject water into the vaporization chamber through an injection pump to heat the vaporization chamber. The vaporization chamber is connected to the reaction chamber. The humidity of the reaction chamber is controlled to be 5%. The alumina catalyst is deactivated by hydrothermal aging. The reaction time is 20 hours.

[0068] Example 5

[0069] A method for regenerating a deactivated γ-Al2O3 catalyst for catalytically decomposing carbon tetrafluoride comprises the following steps:

[0070] S1, filling 2g of γ-Al2O3 catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0071] S2. Pre-introduce CF4 and air into the reaction chamber, with a CF4 flow rate of 0.4 ml / min and an air flow rate of 32.9 ml / min. After the gas path is stable, heat the reaction chamber to 575°C at a heating rate of 5°C / min. -1 ;

[0072] S3, injecting water into the vaporization chamber through an injection pump, heating the vaporization chamber to 150° C., the vaporization chamber is connected to the reaction chamber, and the humidity of the reaction chamber is controlled to be 5% until the catalyst is deactivated, taking out the deactivated catalyst and emptying the reaction chamber;

[0073] S4, loading the deactivated catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0074] S5. Pre-introduce air into the reaction chamber at a flow rate of 32.9 ml / min. After the air path is stable, heat the reaction chamber to 575°C at a heating rate of 5°C / min. -1 ;

[0075] S6. Inject water into the vaporization chamber through an injection pump to heat the vaporization chamber. The vaporization chamber is connected to the reaction chamber. The humidity of the reaction chamber is controlled to be 5%. The alumina catalyst is deactivated by hydrothermal aging. The reaction time is 20 hours.

[0076] Example 6

[0077] A method for regenerating a deactivated γ-Al2O3 catalyst for catalytically decomposing carbon tetrafluoride comprises the following steps:

[0078] S1, filling 2g of γ-Al2O3 catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0079] S2. Pre-introduce CF4 and air into the reaction chamber, with a CF4 flow rate of 0.4 ml / min and an air flow rate of 32.9 ml / min. After the gas path is stable, heat the reaction chamber to 575°C at a heating rate of 5°C / min. -1 ;

[0080] S3, injecting water into the vaporization chamber through an injection pump, heating the vaporization chamber to 150° C., the vaporization chamber is connected to the reaction chamber, and the humidity of the reaction chamber is controlled to be 5% until the catalyst is deactivated, taking out the deactivated catalyst and emptying the reaction chamber;

[0081] S4, loading the deactivated catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0082] S5. Pre-introduce air into the reaction chamber at an air flow rate of 32.9 ml / min. After the air path is stable, heat the reaction chamber to 595°C at a heating rate of 5°C / min. -1 ;

[0083] S6. Inject water into the vaporization chamber through an injection pump to heat the vaporization chamber. The vaporization chamber is connected to the reaction chamber. The humidity of the reaction chamber is controlled to be 5%. The alumina catalyst is deactivated by hydrothermal aging. The reaction time is 20 hours.

[0084] Example 7

[0085] A method for regenerating a deactivated γ-Al2O3 catalyst for catalytically decomposing carbon tetrafluoride comprises the following steps:

[0086] S1, filling 2g of γ-Al2O3 catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0087] S2. Pre-introduce CF4 and air into the reaction chamber, with a CF4 flow rate of 0.4 ml / min and an air flow rate of 32.9 ml / min. After the gas path is stable, heat the reaction chamber to 600°C at a heating rate of 5°C / min. -1 ;

[0088] S3, injecting water into the vaporization chamber through an injection pump, heating the vaporization chamber to 150° C., the vaporization chamber is connected to the reaction chamber, and the humidity of the reaction chamber is controlled to be 5% until the catalyst is deactivated, taking out the deactivated catalyst and emptying the reaction chamber;

[0089] S4, loading the deactivated catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0090] S5. Pre-introduce air into the reaction chamber at a flow rate of 32.9 ml / min. After the air path is stable, heat the reaction chamber to 580°C at a heating rate of 5°C / min. -1 ;

[0091] S6. Inject water into the vaporization chamber through an injection pump to heat the vaporization chamber. The vaporization chamber is connected to the reaction chamber. The humidity of the reaction chamber is controlled to be 5%. The alumina catalyst is deactivated by hydrothermal aging. The reaction time is 20 hours.

[0092] Example 8

[0093] A method for regenerating a deactivated γ-Al2O3 catalyst for catalytically decomposing carbon tetrafluoride comprises the following steps:

[0094] S1, filling 2g of γ-Al2O3 catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0095] S2. Pre-introduce CF4 and air into the reaction chamber, with a CF4 flow rate of 0.4 ml / min and an air flow rate of 32.9 ml / min. After the gas path is stable, heat the reaction chamber to 600°C at a heating rate of 5°C / min. -1 ;

[0096] S3, injecting water into the vaporization chamber through an injection pump, heating the vaporization chamber to 150° C., the vaporization chamber is connected to the reaction chamber, and the humidity of the reaction chamber is controlled to be 5% until the catalyst is deactivated, taking out the deactivated catalyst and emptying the reaction chamber;

[0097] S4, loading the deactivated catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0098] S5. Pre-introduce air into the reaction chamber at a flow rate of 32.9 ml / min. After the air path is stable, heat the reaction chamber to 600°C at a heating rate of 5°C / min. -1 ;

[0099] S6. Inject water into the vaporization chamber through an injection pump to heat the vaporization chamber. The vaporization chamber is connected to the reaction chamber. The humidity of the reaction chamber is controlled to be 5%. The alumina catalyst is deactivated by hydrothermal aging. The reaction time is 20 hours.

[0100] Example 9

[0101] A method for regenerating a deactivated γ-Al2O3 catalyst for catalytically decomposing carbon tetrafluoride comprises the following steps:

[0102] S1, filling 2g of γ-Al2O3 catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0103] S2. Pre-introduce CF4 and air into the reaction chamber, with a CF4 flow rate of 0.4 ml / min and an air flow rate of 32.9 ml / min. After the gas path is stable, heat the reaction chamber to 600°C at a heating rate of 5°C / min. -1 ;

[0104] S3, injecting water into the vaporization chamber through an injection pump, heating the vaporization chamber to 150° C., the vaporization chamber is connected to the reaction chamber, and the humidity of the reaction chamber is controlled to be 5% until the catalyst is deactivated, taking out the deactivated catalyst and emptying the reaction chamber;

[0105] S4, loading the deactivated catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0106] S5. Pre-introduce air into the reaction chamber at an air flow rate of 32.9 ml / min. After the air path is stable, heat the reaction chamber to 620°C at a heating rate of 5°C / min. -1 ;

[0107] S6. Inject water into the vaporization chamber through an injection pump to heat the vaporization chamber. The vaporization chamber is connected to the reaction chamber. The humidity of the reaction chamber is controlled to be 5%. The alumina catalyst is deactivated by hydrothermal aging. The reaction time is 20 hours.

[0108] Example 10

[0109] A method for regenerating a deactivated γ-Al2O3 catalyst for catalytically decomposing carbon tetrafluoride comprises the following steps:

[0110] S1, filling 2g of γ-Al2O3 catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0111] S2. Pre-introduce CF4 and air into the reaction chamber, with a CF4 flow rate of 0.4 ml / min and an air flow rate of 32.9 ml / min. After the gas path is stable, heat the reaction chamber to 550°C at a heating rate of 5°C / min. -1 ;

[0112] S3, injecting water into the vaporization chamber through an injection pump, heating the vaporization chamber to 150° C., the vaporization chamber is connected to the reaction chamber, and the humidity of the reaction chamber is controlled to be 5% until the catalyst is deactivated, taking out the deactivated catalyst and emptying the reaction chamber;

[0113] S4, loading the deactivated catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0114] S5. Pre-introduce air into the reaction chamber at an air flow rate of 32.9 ml / min. After the air path is stable, heat the reaction chamber to 550°C at a heating rate of 5°C / min. -1 ;

[0115] S6. Inject water into the vaporization chamber through an injection pump to heat the vaporization chamber. The vaporization chamber is connected to the reaction chamber. The humidity of the reaction chamber is controlled to be 3%. The alumina catalyst is deactivated by hydrothermal aging. The reaction time is 20 hours.

[0116] Embodiment 11

[0117] A method for regenerating a deactivated γ-Al2O3 catalyst for catalytically decomposing carbon tetrafluoride comprises the following steps:

[0118] S1, filling 2g of γ-Al2O3 catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0119] S2. Pre-introduce CF4 and air into the reaction chamber, with a CF4 flow rate of 0.4 ml / min and an air flow rate of 32.9 ml / min. After the gas path is stable, heat the reaction chamber to 550°C at a heating rate of 5°C / min. -1 ;

[0120] S3, injecting water into the vaporization chamber through an injection pump, heating the vaporization chamber to 150° C., the vaporization chamber is connected to the reaction chamber, and the humidity of the reaction chamber is controlled to be 5% until the catalyst is deactivated, taking out the deactivated catalyst and emptying the reaction chamber;

[0121] S4, loading the deactivated catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0122] S5. Pre-introduce air into the reaction chamber at an air flow rate of 32.9 ml / min. After the air path is stable, heat the reaction chamber to 550°C at a heating rate of 5°C / min. -1 ;

[0123] S6. Inject water into the vaporization chamber through an injection pump to heat the vaporization chamber. The vaporization chamber is connected to the reaction chamber. The humidity of the reaction chamber is controlled to be 5%. The alumina catalyst is deactivated by hydrothermal aging. The reaction time is 20 hours.

[0124] Example 12

[0125] A method for regenerating a deactivated γ-Al2O3 catalyst for catalytically decomposing carbon tetrafluoride comprises the following steps:

[0126] S1, filling 2g of γ-Al2O3 catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0127] S2. Pre-introduce CF4 and air into the reaction chamber, with a CF4 flow rate of 0.4 ml / min and an air flow rate of 32.9 ml / min. After the gas path is stable, heat the reaction chamber to 550°C at a heating rate of 5°C / min. -1 ;

[0128] S3, injecting water into the vaporization chamber through an injection pump, heating the vaporization chamber to 150° C., the vaporization chamber is connected to the reaction chamber, and the humidity of the reaction chamber is controlled to be 5% until the catalyst is deactivated, taking out the deactivated catalyst and emptying the reaction chamber;

[0129] S4, loading the deactivated catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0130] S5. Pre-introduce air into the reaction chamber at an air flow rate of 32.9 ml / min. After the air path is stable, heat the reaction chamber to 550°C at a heating rate of 5°C / min. -1 ;

[0131] S6. Inject water into the vaporization chamber through an injection pump to heat the vaporization chamber. The vaporization chamber is connected to the reaction chamber. The humidity of the reaction chamber is controlled to be 7%. The alumina catalyst is deactivated by hydrothermal aging. The reaction time is 20 hours.

[0132] Embodiment 13

[0133] A method for regenerating a deactivated γ-Al2O3 catalyst for catalytically decomposing carbon tetrafluoride comprises the following steps:

[0134] S1, filling 2g of γ-Al2O3 catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0135] S2. Pre-introduce CF4 and air into the reaction chamber, with a CF4 flow rate of 0.4 ml / min and an air flow rate of 32.9 ml / min. After the gas path is stable, heat the reaction chamber to 550°C at a heating rate of 5°C / min. -1 ;

[0136] S3, injecting water into the vaporization chamber through an injection pump, heating the vaporization chamber to 150° C., the vaporization chamber is connected to the reaction chamber, and the humidity of the reaction chamber is controlled to be 5% until the catalyst is deactivated, taking out the deactivated catalyst and emptying the reaction chamber;

[0137] S4, loading the deactivated catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0138] S5. Pre-introduce air into the reaction chamber at an air flow rate of 32.9 ml / min. After the air path is stable, heat the reaction chamber to 550°C at a heating rate of 5°C / min. -1 ;

[0139] S6. Inject water into the vaporization chamber through an injection pump to heat the vaporization chamber. The vaporization chamber is connected to the reaction chamber. The humidity of the reaction chamber is controlled to be 9%. The alumina catalyst is deactivated by hydrothermal aging. The reaction time is 20 hours.

[0140] Embodiment 14

[0141] A method for regenerating a deactivated γ-Al2O3 catalyst for catalytically decomposing carbon tetrafluoride comprises the following steps:

[0142] S1, filling 2g of γ-Al2O3 catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0143] S2. Pre-introduce CF4 and air into the reaction chamber, with a CF4 flow rate of 0.4 ml / min and an air flow rate of 32.9 ml / min. After the gas path is stable, heat the reaction chamber to 550°C at a heating rate of 5°C / min. -1 ;

[0144] S3, injecting water into the vaporization chamber through an injection pump, heating the vaporization chamber to 150° C., the vaporization chamber is connected to the reaction chamber, and the humidity of the reaction chamber is controlled to be 10% until the catalyst is deactivated, taking out the deactivated catalyst and emptying the reaction chamber;

[0145] S4, loading the deactivated catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0146] S5. Pre-introduce air into the reaction chamber at an air flow rate of 32.9 ml / min. After the air path is stable, heat the reaction chamber to 550°C at a heating rate of 5°C / min. -1 ;

[0147] S6. Inject water into the vaporization chamber through an injection pump to heat the vaporization chamber. The vaporization chamber is connected to the reaction chamber. The humidity of the reaction chamber is controlled to be 8%. The alumina catalyst is deactivated by hydrothermal aging. The reaction time is 20 hours.

[0148] Embodiment 15

[0149] A method for regenerating a deactivated γ-Al2O3 catalyst for catalytically decomposing carbon tetrafluoride comprises the following steps:

[0150] S1, filling 2g of γ-Al2O3 catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0151] S2. Pre-introduce CF4 and air into the reaction chamber, with a CF4 flow rate of 0.4 ml / min and an air flow rate of 32.9 ml / min. After the gas path is stable, heat the reaction chamber to 570°C at a heating rate of 5°C / min. -1 ;

[0152] S3, injecting water into the vaporization chamber through an injection pump, heating the vaporization chamber to 150° C., the vaporization chamber is connected to the reaction chamber, and the humidity of the reaction chamber is controlled to be 10% until the catalyst is deactivated, taking out the deactivated catalyst and emptying the reaction chamber;

[0153] S4, loading the deactivated catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0154] S5. Pre-introduce air into the reaction chamber at a flow rate of 32.9 ml / min. After the air path is stable, heat the reaction chamber to 570°C at a heating rate of 5°C / min. -1 ;

[0155] S6. Inject water into the vaporization chamber through an injection pump to heat the vaporization chamber. The vaporization chamber is connected to the reaction chamber. The humidity of the reaction chamber is controlled to be 10%. The alumina catalyst is deactivated by hydrothermal aging. The reaction time is 20 hours.

[0156] Example 16

[0157] A method for regenerating a deactivated γ-Al2O3 catalyst for catalytically decomposing carbon tetrafluoride comprises the following steps:

[0158] S1, filling 2g of γ-Al2O3 catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0159] S2. Pre-introduce CF4 and air into the reaction chamber, with a CF4 flow rate of 0.4 ml / min and an air flow rate of 32.9 ml / min. After the gas path is stable, heat the reaction chamber to 570°C at a heating rate of 5°C / min. -1 ;

[0160] S3, injecting water into the vaporization chamber through an injection pump, heating the vaporization chamber to 150° C., the vaporization chamber is connected to the reaction chamber, and the humidity of the reaction chamber is controlled to be 10% until the catalyst is deactivated, taking out the deactivated catalyst and emptying the reaction chamber;

[0161] S4, loading the deactivated catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0162] S5. Pre-introduce air into the reaction chamber at a flow rate of 32.9 ml / min. After the air path is stable, heat the reaction chamber to 570°C at a heating rate of 5°C / min. -1 ;

[0163] S6. Inject water into the vaporization chamber through an injection pump to heat the vaporization chamber. The vaporization chamber is connected to the reaction chamber. The humidity of the reaction chamber is controlled to be 12%. The alumina catalyst is deactivated by hydrothermal aging. The reaction time is 20 hours.

[0164] Embodiment 17

[0165] A method for regenerating a deactivated γ-Al2O3 catalyst for catalytically decomposing carbon tetrafluoride comprises the following steps:

[0166] S1, filling 2g of γ-Al2O3 catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0167] S2. Pre-introduce CF4 and air into the reaction chamber, with a CF4 flow rate of 0.4 ml / min and an air flow rate of 32.9 ml / min. After the gas path is stable, heat the reaction chamber to 570°C at a heating rate of 5°C / min. -1 ;

[0168] S3, injecting water into the vaporization chamber through an injection pump, heating the vaporization chamber to 150° C., the vaporization chamber is connected to the reaction chamber, and the humidity of the reaction chamber is controlled to be 10% until the catalyst is deactivated, taking out the deactivated catalyst and emptying the reaction chamber;

[0169] S4, loading the deactivated catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0170] S5. Pre-introduce air into the reaction chamber at a flow rate of 32.9 ml / min. After the air path is stable, heat the reaction chamber to 570°C at a heating rate of 5°C / min. -1 ;

[0171] S6. Inject water into the vaporization chamber through an injection pump to heat the vaporization chamber. The vaporization chamber is connected to the reaction chamber. The humidity of the reaction chamber is controlled to be 14%. The alumina catalyst is deactivated by hydrothermal aging. The reaction time is 20 hours.

[0172] Embodiment 18

[0173] A method for regenerating a deactivated γ-Al2O3 catalyst for catalytically decomposing carbon tetrafluoride comprises the following steps:

[0174] S1, filling 2g of γ-Al2O3 catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0175] S2. Pre-introduce CF4 and air into the reaction chamber, with a CF4 flow rate of 0.4 ml / min and an air flow rate of 32.9 ml / min. After the gas path is stable, heat the reaction chamber to 600°C at a heating rate of 5°C / min. -1 ;

[0176] S3, injecting water into the vaporization chamber through an injection pump, heating the vaporization chamber to 150° C., the vaporization chamber is connected to the reaction chamber, and the humidity of the reaction chamber is controlled to be 15% until the catalyst is deactivated, taking out the deactivated catalyst and emptying the reaction chamber;

[0177] S4, loading the deactivated catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0178] S5. Pre-introduce air into the reaction chamber at a flow rate of 32.9 ml / min. After the air path is stable, heat the reaction chamber to 570°C at a heating rate of 5°C / min. -1 ;

[0179] S6. Inject water into the vaporization chamber through an injection pump to heat the vaporization chamber. The vaporization chamber is connected to the reaction chamber. The humidity of the reaction chamber is controlled to be 13%. The alumina catalyst is deactivated by hydrothermal aging. The reaction time is 20 hours.

[0180] Embodiment 19

[0181] A method for regenerating a deactivated γ-Al2O3 catalyst for catalytically decomposing carbon tetrafluoride comprises the following steps:

[0182] S1, filling 2g of γ-Al2O3 catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0183] S2. Pre-introduce CF4 and air into the reaction chamber, with a CF4 flow rate of 0.4 ml / min and an air flow rate of 32.9 ml / min. After the gas path is stable, heat the reaction chamber to 600°C at a heating rate of 5°C / min. -1 ;

[0184] S3, injecting water into the vaporization chamber through an injection pump, heating the vaporization chamber to 150° C., the vaporization chamber is connected to the reaction chamber, and the humidity of the reaction chamber is controlled to be 15% until the catalyst is deactivated, taking out the deactivated catalyst and emptying the reaction chamber;

[0185] S4, loading the deactivated catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0186] S5. Pre-introduce air into the reaction chamber at a flow rate of 32.9 ml / min. After the air path is stable, heat the reaction chamber to 570°C at a heating rate of 5°C / min. -1 ;

[0187] S6. Inject water into the vaporization chamber through an injection pump to heat the vaporization chamber. The vaporization chamber is connected to the reaction chamber. The humidity of the reaction chamber is controlled to be 15%. The alumina catalyst is deactivated by hydrothermal aging. The reaction time is 20 hours.

[0188] Embodiment 20

[0189] A method for regenerating a deactivated γ-Al2O3 catalyst for catalytically decomposing carbon tetrafluoride comprises the following steps:

[0190] S1, filling 2g of γ-Al2O3 catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0191] S2. Pre-introduce CF4 and air into the reaction chamber, with a CF4 flow rate of 0.4 ml / min and an air flow rate of 32.9 ml / min. After the gas path is stable, heat the reaction chamber to 575°C at a heating rate of 5°C / min. -1 ;

[0192] S3, injecting water into the vaporization chamber through an injection pump, heating the vaporization chamber to 150° C., the vaporization chamber is connected to the reaction chamber, and the humidity of the reaction chamber is controlled to be 15% until the catalyst is deactivated, taking out the deactivated catalyst and emptying the reaction chamber;

[0193] S4, loading the deactivated catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0194] S5. Pre-introduce air into the reaction chamber at a flow rate of 32.9 ml / min. After the air path is stable, heat the reaction chamber to 570°C at a heating rate of 5°C / min. -1 ;

[0195] S6. Inject water into the vaporization chamber through an injection pump to heat the vaporization chamber. The vaporization chamber is connected to the reaction chamber. The humidity of the reaction chamber is controlled to be 17%. The alumina catalyst is deactivated by hydrothermal aging. The reaction time is 20 hours.

[0196] Embodiment 21

[0197] A method for regenerating a deactivated γ-Al2O3 catalyst for catalytically decomposing carbon tetrafluoride comprises the following steps:

[0198] S1, filling 2g of γ-Al2O3 catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0199] S2. Pre-introduce CF4 and air into the reaction chamber, with a CF4 flow rate of 0.4 ml / min and an air flow rate of 32.9 ml / min. After the gas path is stable, heat the reaction chamber to 600°C at a heating rate of 5°C / min. -1 ;

[0200] S3, injecting water into the vaporization chamber through an injection pump, heating the vaporization chamber to 150° C., the vaporization chamber is connected to the reaction chamber, and the humidity of the reaction chamber is controlled to be 15% until the catalyst is deactivated, taking out the deactivated catalyst and emptying the reaction chamber;

[0201] S4, loading the deactivated catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0202] S5. Pre-introduce air into the reaction chamber at a flow rate of 32.9 ml / min. After the air path is stable, heat the reaction chamber to 570°C at a heating rate of 5°C / min. -1 ;

[0203] S6. Inject water into the vaporization chamber through an injection pump to heat the vaporization chamber. The vaporization chamber is connected to the reaction chamber. The humidity of the reaction chamber is controlled to be 19%. The alumina catalyst is deactivated by hydrothermal aging. The reaction time is 20 hours.

[0204] Embodiment 22

[0205] A method for regenerating a deactivated γ-Al2O3 catalyst for catalytically decomposing carbon tetrafluoride comprises the following steps:

[0206] S1, filling 2g of γ-Al2O3 catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0207] S2. Pre-introduce CF4 and air into the reaction chamber, with a CF4 flow rate of 0.4 ml / min and an air flow rate of 32.9 ml / min. After the gas path is stable, heat the reaction chamber to 550°C at a heating rate of 5°C / min. -1 ;

[0208] S3, injecting water into the vaporization chamber through an injection pump, heating the vaporization chamber to 150° C., the vaporization chamber is connected to the reaction chamber, and the humidity of the reaction chamber is controlled to be 5% until the catalyst is deactivated, taking out the deactivated catalyst and emptying the reaction chamber;

[0209] S4, loading the deactivated catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0210] S5. Pre-introduce air into the reaction chamber at a flow rate of 32.9 ml / min. After the air path is stable, heat the reaction chamber to 530°C at a heating rate of 5°C / min. -1 ;

[0211] S6. Inject water into the vaporization chamber through an injection pump to heat the vaporization chamber. The vaporization chamber is connected to the reaction chamber. The humidity of the reaction chamber is controlled to be 7%. The alumina catalyst is deactivated by hydrothermal aging. The reaction time is 10 hours.

[0212] Embodiment 23

[0213] A method for regenerating a deactivated γ-Al2O3 catalyst for catalytically decomposing carbon tetrafluoride comprises the following steps:

[0214] S1, filling 2g of γ-Al2O3 catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0215] S2. Pre-introduce CF4 and air into the reaction chamber, with a CF4 flow rate of 0.4 ml / min and an air flow rate of 32.9 ml / min. After the gas path is stable, heat the reaction chamber to 550°C at a heating rate of 5°C / min. -1 ;

[0216] S3, injecting water into the vaporization chamber through an injection pump, heating the vaporization chamber to 150° C., the vaporization chamber is connected to the reaction chamber, and the humidity of the reaction chamber is controlled to be 5% until the catalyst is deactivated, taking out the deactivated catalyst and emptying the reaction chamber;

[0217] S4, loading the deactivated catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0218] S5. Pre-introduce air into the reaction chamber at a flow rate of 32.9 ml / min. After the air path is stable, heat the reaction chamber to 530°C at a heating rate of 5°C / min. -1 ;

[0219] S6. Inject water into the vaporization chamber through an injection pump to heat the vaporization chamber. The vaporization chamber is connected to the reaction chamber. The humidity of the reaction chamber is controlled to be 7%. The alumina catalyst is deactivated by hydrothermal aging. The reaction time is 20 hours.

[0220] Embodiment 24

[0221] A method for regenerating a deactivated γ-Al2O3 catalyst for catalytically decomposing carbon tetrafluoride comprises the following steps:

[0222] S1, filling 2g of γ-Al2O3 catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0223] S2. Pre-introduce CF4 and air into the reaction chamber, with a CF4 flow rate of 0.4 ml / min and an air flow rate of 32.9 ml / min. After the gas path is stable, heat the reaction chamber to 550°C at a heating rate of 5°C / min. -1 ;

[0224] S3, injecting water into the vaporization chamber through an injection pump, heating the vaporization chamber to 150° C., the vaporization chamber is connected to the reaction chamber, and the humidity of the reaction chamber is controlled to be 15% until the catalyst is deactivated, taking out the deactivated catalyst and emptying the reaction chamber;

[0225] S4, loading the deactivated catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0226] S5. Pre-introduce air into the reaction chamber at a flow rate of 32.9 ml / min. After the air path is stable, heat the reaction chamber to 600°C at a heating rate of 5°C / min. -1 ;

[0227] S6. Inject water into the vaporization chamber through an injection pump to heat the vaporization chamber. The vaporization chamber is connected to the reaction chamber. The humidity of the reaction chamber is controlled to be 5%. The alumina catalyst is deactivated by hydrothermal aging. The reaction time is 30 hours.

[0228] Embodiment 25

[0229] A method for regenerating a deactivated γ-Al2O3 catalyst for catalytically decomposing carbon tetrafluoride comprises the following steps:

[0230] S1, filling 2g of γ-Al2O3 catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0231] S2. Pre-introduce CF4 and air into the reaction chamber, with a CF4 flow rate of 0.4 ml / min and an air flow rate of 32.9 ml / min. After the gas path is stable, heat the reaction chamber to 600°C at a heating rate of 5°C / min. -1 ;

[0232] S3, injecting water into the vaporization chamber through an injection pump, heating the vaporization chamber to 150° C., the vaporization chamber is connected to the reaction chamber, and the humidity of the reaction chamber is controlled to be 15% until the catalyst is deactivated, taking out the deactivated catalyst and emptying the reaction chamber;

[0233] S4, loading the deactivated catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0234] S5. Pre-introduce air into the reaction chamber at a flow rate of 32.9 ml / min. After the air path is stable, heat the reaction chamber to 600°C at a heating rate of 5°C / min. -1 ;

[0235] S6. Inject water into the vaporization chamber through an injection pump to heat the vaporization chamber. The vaporization chamber is connected to the reaction chamber. The humidity of the reaction chamber is controlled to be 15%. The alumina catalyst is deactivated by hydrothermal aging. The reaction time is 10 hours.

[0236] Embodiment 26

[0237] A method for regenerating a deactivated γ-Al2O3 catalyst for catalytically decomposing carbon tetrafluoride comprises the following steps:

[0238] S1, filling 2g of γ-Al2O3 catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0239] S2. Pre-introduce CF4 and air into the reaction chamber, with a CF4 flow rate of 0.4 ml / min and an air flow rate of 32.9 ml / min. After the gas path is stable, heat the reaction chamber to 600°C at a heating rate of 5°C / min. -1 ;

[0240] S3, injecting water into the vaporization chamber through an injection pump, heating the vaporization chamber to 150° C., the vaporization chamber is connected to the reaction chamber, and the humidity of the reaction chamber is controlled to be 15% until the catalyst is deactivated, taking out the deactivated catalyst and emptying the reaction chamber;

[0241] S4, loading the deactivated catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0242] S5. Pre-introduce air into the reaction chamber at a flow rate of 32.9 ml / min. After the air path is stable, heat the reaction chamber to 600°C at a heating rate of 5°C / min. -1 ;

[0243] S6. Inject water into the vaporization chamber through an injection pump to heat the vaporization chamber. The vaporization chamber is connected to the reaction chamber. The humidity of the reaction chamber is controlled to be 15%. The alumina catalyst is deactivated by hydrothermal aging. The reaction time is 20 hours.

[0244] Embodiment 27

[0245] A method for regenerating a deactivated γ-Al2O3 catalyst for catalytically decomposing carbon tetrafluoride comprises the following steps:

[0246] S1, filling 2g of γ-Al2O3 catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0247] S2. Pre-introduce CF4 and air into the reaction chamber, with a CF4 flow rate of 0.4 ml / min and an air flow rate of 32.9 ml / min. After the gas path is stable, heat the reaction chamber to 600°C at a heating rate of 5°C / min. -1 ;

[0248] S3, injecting water into the vaporization chamber through an injection pump, heating the vaporization chamber to 150° C., the vaporization chamber is connected to the reaction chamber, and the humidity of the reaction chamber is controlled to be 5% until the catalyst is deactivated, taking out the deactivated catalyst and emptying the reaction chamber;

[0249] S4, loading the deactivated catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0250] S5. Pre-introduce air into the reaction chamber at a flow rate of 32.9 ml / min. After the air path is stable, heat the reaction chamber to 600°C at a heating rate of 5°C / min. -1 ;

[0251] S6. Inject water into the vaporization chamber through an injection pump to heat the vaporization chamber. The vaporization chamber is connected to the reaction chamber. The humidity of the reaction chamber is controlled to be 15%. The alumina catalyst is deactivated by hydrothermal aging. The reaction time is 30 hours.

[0252] Embodiment 28

[0253] A method for regenerating a deactivated γ-Al2O3 catalyst for catalytically decomposing carbon tetrafluoride comprises the following steps:

[0254] S1, filling 2g of γ-Al2O3 catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0255] S2. Pre-introduce CF4 and air into the reaction chamber, with a CF4 flow rate of 0.4 ml / min and an air flow rate of 32.9 ml / min. After the gas path is stable, heat the reaction chamber to 600°C at a heating rate of 15°C / min. -1 ;

[0256] S3, injecting water into the vaporization chamber through an injection pump, heating the vaporization chamber to 150° C., the vaporization chamber is connected to the reaction chamber, and the humidity of the reaction chamber is controlled to be 15% until the catalyst is deactivated, taking out the deactivated catalyst and emptying the reaction chamber;

[0257] S4, loading the deactivated catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0258] S5. Pre-introduce air into the reaction chamber at a flow rate of 32.9 ml / min. After the air path is stable, heat the reaction chamber to 600°C at a heating rate of 5°C / min. -1 ;

[0259] S6. Inject water into the vaporization chamber through an injection pump to heat the vaporization chamber. The vaporization chamber is connected to the reaction chamber. The humidity of the reaction chamber is controlled to be 15%. The alumina catalyst is deactivated by hydrothermal aging. The reaction time is 20 hours.

[0260] Embodiment 29

[0261] A method for regenerating a deactivated Ni-γ-Al2O3 catalyst for catalytically decomposing carbon tetrafluoride comprises the following steps:

[0262] S1. Fill 2g Ni-γ-Al2O3 catalyst into a quartz tube and fix the quartz tube in a reaction chamber;

[0263] S2. Pre-introduce CF4 and air into the reaction chamber, with a CF4 flow rate of 0.4 ml / min and an air flow rate of 32.9 ml / min. After the gas path is stable, heat the reaction chamber to 600°C at a heating rate of 5°C / min. -1 ;

[0264] S3, injecting water into the vaporization chamber through an injection pump, heating the vaporization chamber to 150° C., the vaporization chamber is connected to the reaction chamber, and the humidity of the reaction chamber is controlled to be 15% until the catalyst is deactivated, taking out the deactivated catalyst and emptying the reaction chamber;

[0265] S4, loading the deactivated catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0266] S5. Pre-introduce air into the reaction chamber at a flow rate of 32.9 ml / min. After the air path is stable, heat the reaction chamber to 600°C at a heating rate of 5°C / min. -1 ;

[0267] S6. Inject water into the vaporization chamber through an injection pump to heat the vaporization chamber. The vaporization chamber is connected to the reaction chamber. The humidity of the reaction chamber is controlled to be 15%. The alumina catalyst is deactivated by hydrothermal aging. The reaction time is 20 hours.

[0268] Embodiment 30

[0269] A method for regenerating a deactivated θ-Al2O3 catalyst for catalytically decomposing carbon tetrafluoride comprises the following steps:

[0270] S1, filling 2g θ-Al2O3 catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0271] S2. Pre-introduce CF4 and air into the reaction chamber, with a CF4 flow rate of 0.4 ml / min and an air flow rate of 32.9 ml / min. After the gas path is stable, heat the reaction chamber to 600°C at a heating rate of 5°C / min. -1 ;

[0272] S3, injecting water into the vaporization chamber through an injection pump, heating the vaporization chamber to 150° C., the vaporization chamber is connected to the reaction chamber, and the humidity of the reaction chamber is controlled to be 15% until the catalyst is deactivated, taking out the deactivated catalyst and emptying the reaction chamber;

[0273] S4, loading the deactivated catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0274] S5. Pre-introduce air into the reaction chamber at a flow rate of 32.9 ml / min. After the air path is stable, heat the reaction chamber to 600°C at a heating rate of 5°C / min. -1 ;

[0275] S6. Inject water into the vaporization chamber through an injection pump to heat the vaporization chamber. The vaporization chamber is connected to the reaction chamber. The humidity of the reaction chamber is controlled to be 15%. The alumina catalyst is deactivated by hydrothermal aging. The reaction time is 20 hours.

[0276] Embodiment 31

[0277] A method for regenerating a deactivated Ga-θ-Al2O3 catalyst for catalytically decomposing carbon tetrafluoride comprises the following steps:

[0278] S1, loading 2 g of Ga-θ-Al2O3 catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0279] S2. Pre-introduce CF4 and air into the reaction chamber, with a CF4 flow rate of 0.4 ml / min and an air flow rate of 32.9 ml / min. After the gas path is stable, heat the reaction chamber to 600°C at a heating rate of 5°C / min. -1 ;

[0280] S3, injecting water into the vaporization chamber through an injection pump, heating the vaporization chamber to 150° C., the vaporization chamber is connected to the reaction chamber, and the humidity of the reaction chamber is controlled to be 15% until the catalyst is deactivated, taking out the deactivated catalyst and emptying the reaction chamber;

[0281] S4, loading the deactivated catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber;

[0282] S5. Pre-introduce air into the reaction chamber at a flow rate of 32.9 ml / min. After the air path is stable, heat the reaction chamber to 600°C at a heating rate of 5°C / min. -1 ;

[0283] S6. Inject water into the vaporization chamber through an injection pump to heat the vaporization chamber. The vaporization chamber is connected to the reaction chamber. The humidity of the reaction chamber is controlled to be 15%. The alumina catalyst is deactivated by hydrothermal aging. The reaction time is 20 hours.

[0284] The catalytic efficiency of the catalysts before deactivation and after regeneration in Examples 1-9 of the present invention was tested at different temperatures. The results are shown in the following table:

[0285] Table 1 Efficiency of γ-Al2O3 catalyst in catalytic decomposition of CF4 at different temperatures

[0286]

[0287] Note: The catalytic temperature is the temperature of the reaction chamber in step S2, and the regeneration temperature is the temperature of the reaction chamber in step S5.

[0288] It can be seen from Table 1 that when the catalytic temperature and regeneration temperature of the γ-Al2O3 catalyst are the same, its catalytic efficiency after deactivation and regeneration is the best, which can basically reach the efficiency before deactivation, and when the catalytic temperature is 600℃, its catalytic efficiency and regeneration catalytic efficiency are the best.

[0289] The catalytic efficiency of the catalysts before deactivation and after regeneration of Examples 10-21 of the present invention was tested at different humidity levels. The results are shown in the following table:

[0290] Table 2 Efficiency of γ-Al2O3 catalyst in catalytic decomposition of CF4 at different humidity

[0291]

[0292] Note: The catalytic humidity is the humidity of the reaction chamber in step S3, and the regeneration humidity is the humidity of the reaction chamber in step S6.

[0293] It can be seen from Table 2 that when the catalytic humidity and regeneration humidity of the γ-Al2O3 catalyst are the same, its catalytic efficiency after deactivation and regeneration is the best, which can basically reach the efficiency before deactivation, and when the catalytic humidity is 15%, its catalytic efficiency and regeneration catalytic efficiency are the best.

[0294] The catalytic efficiency of the catalysts before deactivation and after regeneration of Examples 22-27 of the present invention was tested at different aging times, and the results are shown in the following table:

[0295] Table 3 Efficiency of γ-Al2O3 catalyst for catalytic decomposition of CF4 at different aging times

[0296]

[0297] It can be seen from Table 3 that when the γ-Al2O3 catalyst is deactivated and the hydrothermal aging time is 30 h, its catalytic efficiency after regeneration is the best and can reach the efficiency before deactivation.

[0298] According to the above experiments, the optimal catalytic temperature is 600°C, the optimal catalytic humidity is 15%, the optimal regeneration temperature is 600°C, and the optimal regeneration humidity is 15%. That is, when the regeneration temperature is the same as the catalytic temperature, and the regeneration humidity is the same as the catalytic humidity, the catalytic efficiency after alumina-based regeneration can basically reach the catalytic efficiency before regeneration, and the catalyst can be reused without attenuating the catalytic efficiency.

[0299] In order to verify the regeneration effect of the present invention on other alumina-based catalysts, the above-mentioned optimal test conditions were adopted to set Examples 28-31, and the catalytic efficiency of the catalysts before deactivation and after regeneration was detected. The results are shown in the following table:

[0300] Table 4 Comparison of regeneration performance of different catalysts under optimal experimental conditions

[0301]

[0302] It can be seen from Table 4 that Ni-γ-Al2O3, θ-Al2O3, and Ga-θ-Al2O3 catalysts can be deactivated and regenerated when catalytically decomposing CF4 under the deactivation and regeneration method of the present invention, thereby realizing the recycling of the catalyst.

[0303] like Figure 4 (a) with Figure 4 (b) It can be seen that the structure of the catalyst after deactivation and regeneration in Example 28 of the present invention is basically the same as that of the initial catalyst, and the regeneration process does not destroy its structure. Figure 4 (c) It can be seen that the surface element distribution is basically O and Al, that is, there is basically no aluminum fluoride produced by fluorine poisoning on the surface of the regenerated γ-Al2O3 catalyst.

[0304] like Figure 5 (a) with Figure 5 (b) It can be seen that the structure of the catalyst after deactivation and regeneration in Example 29 of the present invention is basically the same as that of the initial catalyst, such as Figure 5 (c) It can be seen that the surface element distribution is basically O, Al and Ni, that is, there is basically no aluminum fluoride produced by fluorine poisoning on the surface of the regenerated Ni-γ-Al2O3 catalyst, which proves that the method proposed in the present invention can be used for other alumina-based catalysts.

[0305] The above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. A method for regenerating an alumina-based catalyst for catalytically decomposing carbon tetrafluoride, characterized in that: The following steps are involved: S1. Filling the alumina-based catalyst into a quartz tube and fixing the quartz tube in a reaction chamber; S2, pre-introduce CF4 and air into the reaction chamber, and after the gas path is stable, heat the reaction chamber; S3, injecting water into the vaporization chamber through an injection pump to heat the vaporization chamber, wherein the vaporization chamber is connected to the reaction chamber, controlling the humidity of the reaction chamber until the catalyst is deactivated, removing the deactivated catalyst and emptying the reaction chamber; S4, loading the deactivated catalyst into a quartz tube, and fixing the quartz tube in a reaction chamber; S5. Pre-introduce air into the reaction chamber, and after the air path is stable, heat the reaction chamber; S6. Inject water into the vaporization chamber through an injection pump to heat the vaporization chamber. The vaporization chamber is connected to the reaction chamber to control the humidity of the reaction chamber to hydrothermally age the inactivated alumina catalyst.

2. The method for regenerating an alumina-based catalyst for catalytically decomposing carbon tetrafluoride according to claim 1, characterized in that: In step S1, the alumina-based catalyst includes one of a γ-Al2O3 catalyst, a Ni-γ-Al2O3 catalyst, a θ-Al2O3 catalyst or a Ga-θ-Al2O3 catalyst.

3. The method for regenerating an alumina-based catalyst for catalytically decomposing carbon tetrafluoride according to claim 1, characterized in that: In step S2, the CF4 flow rate is 0.3-0.5 ml / min, the air flow rate is 31-33 ml / min, the reaction chamber is heated to 550-600°C, and the heating rate is 4-6°C min -1 .

4. The method for regenerating the deactivated alumina-based catalyst for catalytic decomposition of carbon tetrafluoride according to claim 1, characterized in that: In step S3, the vaporization chamber is heated to 150° C. and the humidity of the reaction chamber is controlled to be 5-15%.

5. The method for regenerating the deactivated alumina-based catalyst for catalytic decomposition of carbon tetrafluoride according to claim 1, characterized in that: In step S5, the air flow rate is 31-33 ml / min, the reaction chamber is heated to 530-620°C, and the heating rate is 4-6°C min -1 .

6. The method for regenerating the deactivated alumina-based catalyst for catalytic decomposition of carbon tetrafluoride according to claim 1, characterized in that: In step S6, the vaporization chamber is heated to 150° C., the humidity of the reaction chamber is controlled to be 3-19%, and the reaction time is 10-30 hours.

7. The method for regenerating the deactivated alumina-based catalyst for catalytic decomposition of carbon tetrafluoride according to claim 1, characterized in that: The temperature of the reaction chamber in step S5 is the same as the temperature of the reaction chamber in step S2.

8. The method for regenerating the deactivated alumina-based catalyst for catalytic decomposition of carbon tetrafluoride according to claim 1, characterized in that: The humidity of the reaction chamber in step S6 is the same as the humidity of the reaction chamber in step S3.

9. The method for regenerating the deactivated alumina-based catalyst for catalytic decomposition of carbon tetrafluoride according to claim 1, characterized in that: In step S2, the air flow rate is 32.9 ml / min, and the heating rate is 5°C min -1 .

10. The method for regenerating the deactivated alumina-based catalyst for catalytic decomposition of carbon tetrafluoride according to claim 1, characterized in that: In step S5, the air flow rate is 32.9 ml / min, and the heating rate is 5°C min -1 .

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