Catalyst for purifying SF6 as well as preparation method and application of catalyst

Abstract

The invention discloses a catalyst for purifying SF6 as well as a preparation method and application thereof, and relates to the technical field of catalysts. According to the catalyst for purifying SF6, CePO4 is adopted as a carrier, LaMnO3 is loaded on the carrier to serve as an active substance, the advantages of CePO4 and LaMnO3 can be combined, the catalyst has excellent low-temperature catalytic activity and SOx selectivity, and the SF6 degradation rate of 95% or above and the SOx selectivity of 92% or above can be obtained at the catalytic temperature of 500 DEG C; meanwhile, the long-range stability of the catalyst is excellent, and the catalyst can still have the SF6 degradation rate of 91% or above and the SOx selectivity of 92% or above after being continuously used for 72 h.

Description

Technical Field

[0001] The present invention relates to the field of catalyst technology, and in particular to a catalyst for purifying SF6, and a preparation method and application thereof. Background Art

[0002] Sulfur hexafluoride (SF6) has excellent insulation and arc-extinguishing properties, making it widely used in medium- and high-voltage electrical switchgear. However, SF6 has a greenhouse gas potential 23,500 times greater than CO2, making it a highly potent greenhouse gas and contributing to serious greenhouse gas emissions. With the increasing adoption of mixed gases like SF6 / N2 and environmentally friendly fluorocarbon insulating gases such as C4F7N, the elimination of pure SF6 insulating gas is only a matter of time. The degradation and disposal of this discarded SF6 has become a critical challenge that urgently needs to be addressed.

[0003] At present, the main treatment methods for waste SF6 include pyrolysis, photolysis, plasma decomposition and thermal catalytic decomposition. The traditional pyrolysis method mainly degrades SF6 through excess CaCO3. However, this reaction needs to be carried out at a high temperature of more than 1100°C, which consumes huge energy and generates toxic gases such as H2S during the degradation process. The photolysis method generally uses a catalyst to promote the conversion of SF6 under the irradiation of ultraviolet or infrared light. This method has relatively low energy consumption, but the treatment time is too long and the treatment efficiency is low. The plasma decomposition method mainly uses plasma equipment to harmlessly treat SF6. It has high degradation efficiency, but the operation is cumbersome and the product selectivity is poor. Thermal catalytic decomposition is the most commonly used SF6 treatment method in industry. This method generally adds a catalyst at a higher temperature to degrade SF6. Through this degradation path, SF6 can be decomposed into non-toxic SO x However, although the existing thermal decomposition catalyst can reduce the temperature of catalytic degradation of SF6, the reaction temperature is still as high as 600℃ or above. x The selectivity is low, and it is easy to produce toxic H2S byproducts. The catalyst is prone to fluorine poisoning and has a short life. Therefore, it is urgent to develop a catalyst that can still have high degradation efficiency at lower temperatures and has high SO x Selective and long-term stable SF6 thermal decomposition catalyst. Summary of the Invention

[0004] In order to solve the shortcomings of the existing technology, the present invention provides a catalyst for purifying SF6, which uses CePO4 as a carrier and loads LaMnO3 on the carrier as an active material. The obtained catalyst can combine the advantages of both and thus has excellent low-temperature catalytic activity and SO xThe selectivity is improved, and the dispersibility of LaMnO3 is improved, and fluorine poisoning is not easy to occur. Therefore, the catalyst of the present invention also has excellent long-term stability.

[0005] Another object of the present invention is to provide a method for preparing a catalyst for purifying SF6.

[0006] Another object of the present invention is to provide an application of a catalyst for purifying SF6.

[0007] The above-mentioned purpose of the present invention is achieved through the following technical solutions:

[0008] A catalyst for purifying SF6 comprises a carrier and an active component, wherein the carrier comprises CePO4, the active component comprises LaMnO3, and the mass proportion of LaMnO3 in the catalyst for purifying SF6 is 5.5-22.0%.

[0009] In the catalyst provided by the present invention, CePO4 as a carrier has good catalytic activity for the thermal decomposition of SF6 at medium and high temperatures (generally 600-800°C), but the catalytic activity is poor at lower temperatures of 450-600°C. The inventors of this application have found through extensive experimental research that the introduction of LaMnO3 as an active substance into the CePO4 carrier can make the catalyst surface have rich active groups, which can enhance the intermediate products (such as SOF x etc.), which not only improves the SF6 decomposition efficiency at low temperature, but also reduces the SO x At the same time, LaMnO3, as an active material, is loaded onto the surface of the CePO4 carrier, which can have higher dispersibility and avoid fluorine poisoning during the catalytic process. Therefore, the catalyst in this application can also have excellent long-term stability and excellent catalytic degradation rate and target product selectivity after long-term use.

[0010] In a specific embodiment of the present invention, the mass proportion of LaMnO3 in the catalyst for purifying SF6 is calculated based on the amount of raw materials added during the preparation process. The raw materials added in this application are completely converted into the target product.

[0011] Preferably, the particle size of the carrier is 0.15 to 0.30 mm.

[0012] The present invention also protects a method for preparing the above-mentioned catalyst for purifying SF6, comprising the following steps:

[0013] The raw materials for preparation are mixed under solution conditions to obtain a mixture, wherein the raw materials for preparation include a carrier, a manganese source and a lanthanum source; the obtained mixture is subjected to solid-liquid separation and calcined to obtain a catalyst for purifying SF6.

[0014] Preferably, the molar ratio of the manganese element in the manganese source to the CePO4 in the carrier is (5-21):100.

[0015] Preferably, the molar ratio of the manganese element in the manganese source to the lanthanum element in the lanthanum source is (0.5-2):1.

[0016] In a specific embodiment of the present invention, the solid-liquid separation can be performed by any conventional operation in the art, such as filtration.

[0017] More preferably, the calcination temperature is 700-900° C. and the calcination time is 2-5 hours.

[0018] More preferably, the solution conditions are provided by ethanol.

[0019] More preferably, the carrier is CePO4, and the preparation method of CePO4 comprises the following steps:

[0020] The cerium source and phosphoric acid are mixed under solution conditions, the pH value of the solution is adjusted to 9-14, and CePO4 is obtained after aging, drying and calcining.

[0021] Preferably, the molar ratio of the cerium source to the phosphoric acid is (0.5-2):1.

[0022] In a specific embodiment of the present invention, the cerium source includes cerium nitrate.

[0023] In a specific embodiment of the present invention, the above solution conditions are provided by water.

[0024] In a specific embodiment of the present invention, the pH is adjusted by adding ammonia water to the reaction system. More specifically, the pH is adjusted to 9 to 14 by adding excess ammonia water to the reaction system. More specifically, the pH is 10.

[0025] In a specific embodiment of the present invention, the aging temperature is 30-50° C. and the aging time is 12-24 hours. More specifically, the aging step further includes a filtration step.

[0026] In a specific embodiment of the present invention, the drying temperature is 80-120° C. and the drying time is 10-24 hours.

[0027] In a specific embodiment of the present invention, the calcination temperature is 380-480° C. and the calcination time is 2-5 hours.

[0028] Preferably, the manganese source comprises manganese nitrate.

[0029] Preferably, the lanthanum source comprises lanthanum nitrate.

[0030] The present invention also protects the use of the above catalyst for purifying SF6 in catalytic degradation of SF6.

[0031] The present invention also provides a method for catalytically degrading SF6-containing waste gas, comprising the following steps:

[0032] In the presence of H2O2, the catalyst for purifying SF6 is used to catalytically degrade the exhaust gas containing SF6.

[0033] In the method for catalytic degradation of SF6-containing waste gas provided by the present invention, H2O2 can be used as an activator to further enhance the catalytic performance of the catalyst. Specifically, H2O2 can decompose on the surface of the catalyst including the CePO4 carrier and LaMnO3 to produce acidic sites and hydroxyl groups, active oxygen and other groups with strong oxidizing properties, thereby reducing the activation energy required for SF6 degradation, thereby further promoting the low-temperature degradation of SF6. At the same time, the catalyst of the present invention also has good catalytic decomposition ability for H2O2, and can greatly enhance its own catalytic performance for SF6 degradation reaction by promoting the degradation of H2O2. Therefore, there is a synergistic effect between H2O2 and the LaMnO3 / CePO4 catalyst. In the presence of H2O2, the catalyst used to purify SF6 catalytically degrades SF6-containing waste gas, which can further enhance the effect of catalytic degradation of SF6.

[0034] Preferably, the H2O2 is provided by an H2O2 aqueous solution, and the volume ratio of the H2O2 aqueous solution to the SF6-containing waste gas is (1-10):100.

[0035] In a specific embodiment of the present invention, the aqueous H2O2 solution is introduced into the reaction system by spraying. More specifically, the catalytic degradation of SF6-containing waste gas is carried out in a fixed-bed quartz tube reactor, with the aqueous H2O2 solution injected into the reactor tube via a syringe pump. Under high temperature conditions, the aqueous H2O2 solution rapidly vaporizes and mixes evenly with other gases.

[0036] Preferably, the volume proportion of SF6 in the SF6-containing waste gas is 1 to 10 vol.%.

[0037] More preferably, the temperature for catalytic degradation of SF6-containing waste gas is 450-600°C.

[0038] More preferably, the volume space velocity of the catalytic degradation of SF6-containing waste gas is 1000 to 3000 mL / mg·h.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] The catalyst provided by the present invention can achieve a SF6 degradation rate of more than 95% and a SO degradation rate of more than 92% at a catalytic temperature of 500°C in the presence of hydrogen peroxide. x It is selective and has excellent long-term stability. After 72 hours of continuous use, it can still have a SF6 degradation rate of more than 91% and a SO x Selective. DETAILED DESCRIPTION

[0041] The present invention will be further described below in conjunction with specific embodiments, but the examples do not limit the present invention in any form. Unless otherwise specified, the raw materials and reagents used in the examples of the present invention are conventionally purchased raw materials and reagents. Among them, the raw material information used in each example and comparative example is as follows:

[0042] H2O2 aqueous solution: commercially available, concentration is 30wt%.

[0043] Ethanol: Commercially available, anhydrous ethanol.

[0044] CePO4: Homemade, the preparation method includes the following steps:

[0045] Weigh 0.06 mol Ce(NO3)3·6H2O and 100 mL H2O, stir evenly at room temperature to obtain solution A; weigh 0.06 mol H3PO4 and 100 mL H2O, stir evenly at room temperature to obtain solution B; slowly add solution A dropwise to solution B, add excess ammonia water to obtain a mixed solution with a pH of 10; place the mixed solution in an oven at 40°C for aging for 12 h, wash and filter, then dry at 100°C for 12 h, and finally place it in a muffle furnace and calcine at 450°C for 4 h to obtain CePO4.

[0046] AlPO4: Homemade, the preparation method includes the following steps:

[0047] Weigh 0.06 mol Al(NO3)3·9H2O and 100 mL H2O, stir evenly at room temperature to obtain solution A; weigh 0.06 mol H3PO4 and 100 mL H2O, stir evenly at room temperature to obtain solution B; slowly add solution A dropwise to solution B, add excess ammonia water to obtain a mixed solution with a pH of 10; place the mixed solution in an oven at 40°C for aging for 12 h, wash and filter, then dry at 100°C for 12 h, and finally place it in a muffle furnace and calcine at 450°C for 4 h to obtain AlPO4.

[0048] Example 1

[0049] A catalyst for purifying SF6 comprises a carrier CePO4 and an active component LaMnO3, wherein the content of LaMnO3 is 11.0 wt%.

[0050] The preparation method of the catalyst in this embodiment comprises the following steps:

[0051] 0.55 g (0.0022 mol) of manganese nitrate Mn(NO3)2·4H2O, 0.97 g (0.0022 mol) of lanthanum nitrate La(NO3)3·6H2O and 5 g (0.02127 mol) of CePO4 were mixed in 100 mL of ethanol to obtain a mixture. After solid-liquid separation, the obtained mixture was calcined at 800°C for 3 h to obtain a catalyst for purifying SF6.

[0052] Example 2

[0053] A catalyst for purifying SF6, which differs from Example 1 only in that:

[0054] The content of LaMnO3 in the catalyst is 5.5 wt%.

[0055] The preparation method of the catalyst in this embodiment is different from that in Example 1 only in that:

[0056] The amount of lanthanum nitrate Mn(NO3)2·4H2O added is 0.0011 mol, and the amount of manganese nitrate La(NO3)3·6H2O added is 0.0011 mol.

[0057] Example 3

[0058] A catalyst for purifying SF6, which differs from Example 1 only in that:

[0059] The content of LaMnO3 in the catalyst is 22.0 wt%.

[0060] The preparation method of the catalyst in this embodiment is different from that in Example 1 only in that:

[0061] The amount of lanthanum nitrate Mn(NO3)2·4H2O added is 0.0044 mol, and the amount of manganese nitrate La(NO3)3·6H2O added is 0.044 mol.

[0062] Comparative Example 1

[0063] A catalyst for purifying SF6, which differs from Example 1 only in that:

[0064] The active component LaMnO3 is not included, only the carrier CePO4 is included.

[0065] The preparation method of the catalyst in this comparative example is the preparation method of CePO4.

[0066] Comparative Example 2

[0067] A catalyst for purifying SF6, which differs from Example 1 only in that:

[0068] The carrier CePO4 is not included, and only the active component LaMnO3 is included.

[0069] The preparation method of the catalyst in this comparative example is different from that in Example 1 only in that:

[0070] CePO4 is not included in the preparation raw materials.

[0071] Comparative Example 3

[0072] A catalyst for purifying SF6, which differs from Example 1 only in that:

[0073] The active component LaMnO3 is replaced by MnO2.

[0074] The preparation method of the catalyst in this comparative example is different from that in Example 1 only in that:

[0075] The preparation raw materials do not include manganese nitrate La(NO3)3·6H2O.

[0076] Comparative Example 4

[0077] A catalyst for purifying SF6, which differs from Example 1 only in that:

[0078] The support CePO4 was replaced by AlPO4.

[0079] The preparation method of the catalyst in this comparative example is different from that in Example 1 only in that:

[0080] CePO4 was replaced by AlPO4 in the preparation raw materials.

[0081] Comparative Example 5

[0082] A catalyst for purifying SF6, which differs from Example 1 only in that:

[0083] The active component LaMnO3 is replaced by LaNiO3.

[0084] The preparation method of the catalyst in this comparative example is different from that in Example 1 only in that:

[0085] In the preparation raw materials, manganese nitrate La(NO3)3·6H2O is replaced by nickel nitrate Ni(NO3)2.

[0086] Performance Testing

[0087] 1. Catalytic performance test

[0088] 1.1 Catalytic activity test

[0089] Next, the degradation rate of reactants and selectivity of target products in catalytic degradation of SF6-containing waste gas by the catalysts obtained in the examples and comparative examples were tested. The testing method includes the following steps:

[0090] Take 2.3mL of catalyst and put it into a fixed-bed quartz tube reactor with an inner diameter of 1cm; connect a pipe with several nozzles to the fixed-bed quartz tube reactor, so that the H2O2 aqueous solution flows through the pipe and enters the reactor by spraying; introduce SF6-containing waste gas, wherein the initial composition of the SF6-containing waste gas is SF6 = 1vol.%, O2 = 3vol.%, and the balance is N2; the volume ratio of the H2O2 aqueous solution to the SF6-containing waste gas is 5:100, and the volume space velocity of the SF6-containing waste gas is 2000mL / mg·h. The reaction temperature for the catalytic degradation of SF6-containing waste gas is 450-600℃, and the SF6 concentration in the reaction tail gas is detected by GC9790Ⅱ gas chromatography (Fuli) and converted to obtain the SF6 degradation rate, SO x The content and selectivity were detected by DIONEX AQUION ion chromatography (Thermo Fisher Scientific) after absorption with NaOH.

[0091] 1.2 Long-range stability test

[0092] The long-term stability of the catalysts obtained in the examples and comparative examples in catalytic degradation of SF6-containing exhaust gas was tested, and the testing method included the following steps:

[0093] The catalysts obtained in the examples and comparative examples were subjected to continuous degradation of SF6-containing exhaust gas at 500°C (other conditions were the same as those in Section 1.1) for 72 hours. After 72 hours, the degradation rates of SF6 and SO x selectivity.

[0094] The data of the above performance test are shown in Table 1 below:

[0095] Table 1. Catalytic performance of the catalysts obtained in the examples and comparative examples

[0096]

[0097] Note: “ / ” in Table 1 above means no test was performed.

[0098] Comparing the data of Example 1 with Comparative Examples 1-2, it can be seen that the CePO4 carrier alone (Comparative Example 1) does not have good low-temperature SF6 degradation performance, which is mainly due to its poor redox performance and inability to effectively activate SF6; and the LaMnO3 carrier alone (Comparative Example 2) does not show good reaction stability, which is mainly due to the fact that its active sites are susceptible to the poisoning effect of degradation byproducts, resulting in catalyst poisoning and inactivation. The LaMnO3 / CePO4 catalyst provided by the present invention can enhance the redox ability of the catalyst through the strong interaction between the two, while suppressing the poisoning effect of degradation byproducts on the active sites, ultimately showing good low-temperature SF6 degradation performance and long-term reaction stability.

[0099] According to Comparative Examples 3 to 5, replacing LaMnO3 with MnO2 (Comparative Example 3) will result in poor long-term reaction stability of the catalyst, while replacing CePO4 with AlPO4 or replacing LaMnO3 with LaNiO3 (Comparative Examples 4 to 5) will result in the failure to achieve the excellent SF6 degradation performance of the present invention.

[0100] 2. Catalytic Conditions

[0101] The catalysts obtained in Example 1 and Comparative Example 1 were used to catalytically degrade SF6 under different conditions to explore the optimal catalytic conditions. The reactions of catalytically degrading SF6 under different conditions are shown in Application Examples 1 to 6.

[0102] Application Example 1.

[0103] A method for catalytically degrading SF6-containing waste gas comprises the following steps:

[0104] Take 2.3mL of the catalyst of Example 1 and put it into a fixed-bed quartz tube reactor with an inner diameter of 1cm; connect a pipe with several nozzles to the fixed-bed quartz tube reactor, so that the H2O2 aqueous solution flows through the pipe and enters the reactor by spraying; introduce SF6-containing waste gas, wherein the initial composition of the SF6-containing waste gas is SF6=1vol.%, O2=3vol.%, and the balance is N2; the volume ratio of the H2O2 aqueous solution to the SF6-containing waste gas is 5:100, and the volume space velocity of the SF6-containing waste gas is 2000mL / mg·h. The reaction temperature for the catalytic degradation of SF6-containing waste gas is 450-600℃, and the SF6 concentration in the reaction tail gas is detected by GC9790Ⅱ gas chromatography (Fuli) and converted to obtain the SF6 degradation rate, SO x The content and selectivity were detected by DIONEX AQUION ion chromatography (Thermo Fisher Scientific) after absorption with NaOH.

[0105] Application Example 2.

[0106] A method for catalytically degrading SF6-containing waste gas, which differs from Application Example 1 only in that:

[0107] The H2O2 aqueous solution was replaced with an equal volume of water.

[0108] Application Example 3.

[0109] A method for catalytically degrading SF6-containing waste gas, which differs from Application Example 1 only in that:

[0110] The volume ratio of the H2O2 aqueous solution and the SF6-containing waste gas flowing through the pipe with the nozzle is 1:100.

[0111] Application Example 4.

[0112] A method for catalytically degrading SF6-containing waste gas, which differs from Application Example 1 only in that:

[0113] The volume ratio of the H2O2 aqueous solution and the SF6-containing waste gas flowing through the pipe with the nozzle is 10:100.

[0114] Application Example 5.

[0115] A method for catalytically degrading SF6-containing waste gas, which differs from Application Example 1 only in that:

[0116] The catalyst in Example 1 was replaced by the catalyst in Comparative Example 1, and the H2O2 aqueous solution was replaced by an equal volume of water.

[0117] Application Example 6.

[0118] A method for catalytically degrading SF6-containing waste gas, which differs from Application Example 1 only in that:

[0119] The catalyst of Example 1 was replaced by the catalyst of Comparative Example 1, and the initial O2 content in the SF6 exhaust gas was adjusted to 30 vol.%. At the same time, the H2O2 aqueous solution was replaced by an equal volume of water.

[0120] The catalytic effect test data of the above application example is shown in Table 2 below:

[0121] Table 2. Catalytic effect test data of application examples 1 to 6

[0122]

[0123] Note: “ / ” in Table 2 above means no test was performed.

[0124] As shown in Table 2 above, the presence of hydrogen peroxide significantly improves the SF6 degradation performance of the catalyst of the present invention at low temperatures. This is primarily due to the decomposition of hydrogen peroxide on the surface of the LaMnO3 / CePO4 composite catalyst to produce more oxidizing active groups (such as active oxygen and active hydroxyl groups). These active groups can reduce the activation energy required for SF6 degradation, thereby promoting low-temperature SF6 degradation. According to Application Examples 1, 3, and 4, increasing the hydrogen peroxide content can further enhance catalytic activity. However, increasing the volume ratio of H2O2 to SF6 exhaust gas from 5:100 (Application Example 1) to 10:100 (Application Example 4) reduces the degree of improvement in catalytic activity.

[0125] According to Application Examples 2 and 5, the catalytic degradation of SF6 was performed without the introduction of hydrogen peroxide. The catalytic performance of the catalyst in Comparative Example 1 containing only the carrier CePO4 was significantly inferior to that of the catalyst in Example 1, indicating that the catalytic performance of the catalyst of the present invention was superior to that of pure CePO4 under conventional catalytic conditions.

[0126] According to Comparative Example 1, Application Example 5 and Application Example 6, it can be seen that the excellent catalytic effect of the present invention cannot be achieved by replacing hydrogen peroxide with oxygen, indicating that the introduction of hydrogen peroxide can improve the performance of the catalyst in degrading SF6. The intrinsic reason is that hydrogen peroxide decomposes on the catalyst surface to produce more oxidizing active groups (such as active oxygen and active hydroxyl groups, etc.). These active groups can reduce the activation energy required for SF6 degradation and promote the low-temperature degradation of SF6.

[0127] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A catalyst for purifying SF6, characterized in that: The catalyst comprises a carrier and an active component, wherein the carrier comprises CePO4, the active component comprises LaMnO3, and the content of LaMnO3 in the catalyst for purifying SF6 is 5.5-22.0 wt%.

2. The catalyst for purifying SF6 according to claim 1, characterized in that: The particle size of the carrier is 0.15-0.30 mm.

3. A method for preparing a catalyst for purifying SF6 according to claim 1 or 2, characterized in that: The steps include: The raw materials for preparation are mixed under solution conditions to obtain a mixture, wherein the raw materials for preparation include a carrier, a manganese source and a lanthanum source; the obtained mixture is subjected to solid-liquid separation and calcined to obtain a catalyst for purifying SF6.

4. The method for preparing a catalyst for purifying SF6 according to claim 3, wherein: The molar ratio of the manganese element in the manganese source to the CePO4 in the carrier is (5-21):

100.

5. The method for preparing a catalyst for purifying SF6 according to claim 3 or 4, characterized in that: Include at least one of the following (a) to (e): (a) the calcination temperature is 700-900° C. and the calcination time is 2-5 hours; (b) the solution condition is provided by ethanol; (c) The carrier is CePO4, and the preparation method of CePO4 comprises the following steps: The cerium source is mixed with phosphoric acid under solution conditions, the pH of the solution is adjusted to 9-14, and CePO4 is obtained after aging, drying and calcining; (d) the manganese source comprises manganese nitrate; (e) The lanthanum source comprises lanthanum nitrate.

6. Use of the catalyst for purifying SF6 according to claim 1 or 2 in catalytic degradation of SF6.

7. A method for catalytic degradation of SF6-containing waste gas, characterized in that: The steps include: In the presence of H2O2, the catalyst for purifying SF6 according to claim 1 or 2 is used to catalytically degrade the exhaust gas containing SF6.

8. The method for catalytic degradation of SF6-containing waste gas according to claim 7, characterized in that: The H2O2 is provided by an H2O2 aqueous solution, and the volume ratio of the H2O2 aqueous solution to the SF6-containing waste gas is (1-10):

100.

9. The method for catalytic degradation of SF6-containing waste gas according to claim 7, characterized in that: The volume proportion of SF6 in the SF6-containing waste gas is 1 to 10 vol.%.

10. The method for catalytic degradation of SF6-containing waste gas according to claim 8 or 9, characterized in that: Include at least one of the following (f) to (g): (f) the temperature of the catalytic degradation of SF6-containing waste gas is 450-600°C; (g) The volume space velocity of the catalytic degradation of SF6-containing waste gas is 1000 to 3000 mL / mg·h.

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