Method for realizing efficient light-driven nitrous oxide degradation by using copper-based supported catalyst

Abstract

The invention discloses a method for realizing efficient light-driven nitrous oxide degradation by using a copper-based supported catalyst, which comprises the following steps: under illumination, carrying out contact reaction on nitrous oxide or mixed gas containing nitrous oxide and the copper-based supported catalyst, and carrying out photo-thermal synergistic degradation on nitrous oxide under the condition that light is used as unique energy input, the light for illumination comprises visible light and / or ultraviolet light; a carrier of the copper-based supported catalyst is TiO2; and during the contact reaction, the surface temperature of the copper-based supported catalyst is greater than 100 DEG C. According to the method, the electronic state of copper in the catalyst is regulated and controlled by utilizing the electron interaction between copper and the carrier TiO2 in the copper-based supported catalyst, meanwhile, the light absorption area is widened by utilizing the catalyst, the light energy utilization rate is improved, and effective catalytic degradation of photo-thermal synergetic N2O under intermittent and continuous flow conditions is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of environmental catalysis, and in particular to a method for realizing efficient light-driven nitrous oxide degradation using a copper-based supported catalyst. Background Art

[0002] With economic development and rising living standards, environmental pollution has become a growing concern. Nitrous oxide (N2O) is a stable greenhouse gas in the atmosphere with a global warming potential (GWP) approximately 300 times that of carbon dioxide. It can remain stable in the atmosphere for approximately 116 years. Among greenhouse gases, N2O contributes 4% to the greenhouse effect, making it the third most potent. Furthermore, N2O damages the ozone layer, contributing to its depletion. Rapidly increasing N2O emissions pose a significant threat to the environment, impacting climate change and human health. N2O comes from a wide range of sources, including nitrogen-containing fertilizers, chemical industry (such as adipic acid, nitric acid, and caprolactam production), and coal combustion exhaust. Reducing N2O emissions not only helps mitigate global warming but also plays a key role in protecting stratospheric ozone. Compared to dispersed agricultural N2O emissions, industrial N2O exhaust emissions are more concentrated, making them easier to treat. Currently, thermal catalytic direct N2O degradation technology is widely used to reduce industrial N2O emissions. However, it requires high-temperature operation, typically exceeding 400°C, and faces challenges such as high energy consumption, secondary pollution from nitrogen oxides, the use of large amounts of catalyst, and low catalyst resistance to water and sintering. In contrast, light-driven reactions, which use clean sunlight to drive N2O degradation at room temperature, effectively alleviate the high energy consumption of traditional thermal catalysis, which relies on fossil fuel combustion for heating, catalyst sintering and deactivation, and the production of nitrogen oxides at high temperatures.

[0003] At present, the research on light-driven N2O degradation is still immature, the N2O degradation rate is low, and most reactions are intermittent reactions, mainly using light in the ultraviolet or ultraviolet-visible region, with low light energy utilization. These limitations hinder the further development and application of light-driven N2O catalytic degradation. Catalysts are the core of catalytic reactions. There have been many studies on photocatalysts for light-driven N2O degradation, mainly including typical photocatalysts (such as TiO2, ZnO, WO3, C3N4, BiVO x However, existing reports mainly use gas-solid phase batch reactions to achieve N2O degradation, with poor catalyst performance. The N2O conversion rate within 4 hours is mostly 15-30%, and the reaction kinetic constant is 0.006-0.098h -1(Wang, L.; Liu, J.; Song, W.; Wang, H.; Li, Y.; Liu, J.; Zhao, Z.; Tan, J.; Duan, Z.; Deng, J. Experimental and DFT Insights of BiVO4 as an Effective Photocatalytic Catalyst for N2ODecomposition.Chem.Eng.J.2019,366,504-513; Liu, J.; Wang, L.; Song, W.; Zhao, M.; Liu, J.; Wang, H.; Zhao, Z.; Xu, C.; Duan, Z.BiMO x Semiconductors as Catalysts for Photocatalytic Decomposition of N2O: A Combination of Experimental and DFT+UStudy. ACS Sustainable Chem. Eng. 2018, 7, 2811-2820). Furthermore, existing photocatalytic research primarily utilizes light in the ultraviolet (UV) or UV and visible regions, failing to achieve efficient utilization of full-spectrum light energy.

[0004] Therefore, how to construct an effective photocatalytic catalyst and how to combine the catalyst with the reactor to realize the utilization of full-spectrum light energy to achieve efficient N2O degradation have become technical problems that need to be solved urgently. Summary of the Invention

[0005] In response to the above technical problems and the shortcomings in the field, the present invention provides a method for achieving efficient light-driven nitrous oxide degradation using a copper-based supported catalyst. The electronic state of copper in the copper-based supported catalyst is regulated by the electronic interaction between copper and the carrier TiO2. At the same time, the catalyst is used to broaden the light absorption area and improve the utilization rate of light energy. With light as the only energy input, effective photothermal synergistic catalytic degradation of N2O under intermittent and continuous flow conditions is achieved.

[0006] The specific technical solutions are as follows:

[0007] A method for achieving efficient light-driven nitrous oxide degradation using a copper-based supported catalyst, comprising: contacting nitrous oxide or a mixed gas containing nitrous oxide with the copper-based supported catalyst under light, and degrading nitrous oxide by photothermal synergy with light as the only energy input;

[0008] The light used for the illumination includes visible light and / or ultraviolet light;

[0009] The carrier of the copper-based supported catalyst is TiO2;

[0010] During the contact reaction, the surface temperature of the copper-based supported catalyst is greater than 100°C.

[0011] The inventors found that the electronegativity of the metal Ti in the carrier TiO2 is less than that of copper, which can induce the copper on the carrier TiO2 to form more low-valent sites (Cu + ), which is beneficial to the photothermal synergistic catalytic degradation of N2O.

[0012] In some embodiments, the method for achieving efficient light-driven nitrous oxide degradation using a copper-based supported catalyst may include irradiation with infrared light. Furthermore, the irradiation may be sunlight or a combination of sunlight-simulated light, such as a xenon lamp.

[0013] In some embodiments, the copper-based supported catalyst is used to achieve efficient light-driven nitrous oxide degradation, and the light intensity of the light can be 500-700 mW / cm 2 This light intensity condition can increase the surface temperature of the copper-based supported catalyst to an appropriate value, promoting the photothermal synergistic degradation of N2O by the catalyst.

[0014] In some embodiments, the copper-based supported catalyst described herein implements a method for efficiently light-driven nitrous oxide degradation, wherein the gas mixture, except for nitrous oxide, comprises inert gases that do not participate in the reaction, such as argon or other noble gases. The catalyst and method of the present invention can directly catalyze the degradation of NO to produce nitrogen and oxygen without the involvement of other reactants.

[0015] In some embodiments, in the method for achieving efficient light-driven nitrous oxide degradation using a copper-based supported catalyst, the volume concentration X of nitrous oxide in the mixed gas may satisfy 0.1% ≤ X < 100%, for example, 1%, 5%, 10%, 20%, 30%, 50%, 70%, 90%, etc. The volume concentration of N2O in the exhaust gas from adipic acid plants is generally about 10%.

[0016] In some embodiments, the copper-based supported catalyst realizes a method for efficiently light-driven nitrous oxide degradation, and the copper loading in the copper-based supported catalyst may be 0.5 wt% to 10 wt%, for example, 1 wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt%, 6 wt%, 7 wt%, 7.5 wt%, 8 wt%, 8.5 wt%, 9 wt%, etc.

[0017] In some embodiments, the copper-based supported catalyst is used to realize the method of efficient light-driven nitrous oxide degradation, wherein the copper in the copper-based supported catalyst is Cu + and Cu 2+ Exists in mixed forms.

[0018] In some embodiments, the method for achieving efficient light-driven nitrous oxide degradation using the copper-based supported catalyst may include: adding a Cu(II) precursor solution to a TiO2 dispersion under stirring, maintaining stirring after the addition is complete and heating to evaporate the solvent, drying and calcining the resulting mixture to obtain the copper-based supported catalyst.

[0019] In some embodiments, in the method for preparing the copper-based supported catalyst, the Cu(II) precursor may be copper nitrate, copper chloride, copper sulfate, etc.

[0020] In some embodiments, in the method for preparing the copper-based supported catalyst, the heating temperature may be 60-100° C., for example, 80° C.

[0021] In some embodiments, in the method for preparing the copper-based supported catalyst, the drying temperature can be 75-85° C., such as 80° C., and the drying time can be more than 6 hours, such as 12 hours.

[0022] In some embodiments, in the method for preparing the copper-based supported catalyst, the calcination temperature may be 450-550° C., for example, 500±5° C.

[0023] In some embodiments, in the method for preparing the copper-based supported catalyst, the calcination holding time can be 2 to 8 hours, such as 3 hours.

[0024] In some embodiments, in the method for preparing the copper-based supported catalyst, the calcination atmosphere may be air.

[0025] In some embodiments, in the method for preparing the copper-based supported catalyst, the heating rate of the calcination may be 1 to 10° C. / min, for example, 5° C. / min.

[0026] In some embodiments, the copper-based supported catalyst realizes a method for efficiently light-driven nitrous oxide degradation. During the contact reaction, the surface temperature of the copper-based supported catalyst is greater than 240°C, and further greater than or equal to 260°C, which is conducive to the photothermal synergistic degradation of N2O.

[0027] In some embodiments, the method for achieving efficient light-driven nitrous oxide degradation using a copper-based supported catalyst can be performed in an intermittent or continuous flow mode, or a combination thereof. When the method is intermittent, the nitrous oxide or the nitrous oxide-containing gas mixture can be static. When the method is continuous flow, the nitrous oxide or the nitrous oxide-containing gas mixture can be flowing, and further, the gas flow rate of the nitrous oxide or the nitrous oxide-containing gas mixture can be 5 to 30 mL / min.

[0028] In some embodiments, in the method for achieving efficient light-driven nitrous oxide degradation using a copper-based supported catalyst, during the contact reaction, the nitrous oxide or the nitrous oxide-containing gas mixture can be in a static or flowing state. Furthermore, when the nitrous oxide or the nitrous oxide-containing gas mixture is in a flowing state, the gas flow rate of the nitrous oxide or the nitrous oxide-containing gas mixture can be 5 to 30 mL / min.

[0029] In some embodiments, the method for achieving efficient light-driven nitrous oxide degradation using a copper-based supported catalyst can use a stainless steel photocatalytic reactor. The stainless steel photocatalytic reactor has slow heat diffusion and can achieve light-driven synergistic effects of heat and light.

[0030] Furthermore, the stainless steel photocatalytic reactor may include a reaction chamber, a partition through which a circulating medium can pass is provided on the outside of the reaction chamber, the reaction chamber has an air inlet, an air outlet and a thermocouple insertion hole, the copper-based supported catalyst is placed in the reaction chamber, and the air inlet is used to receive the nitrous oxide or the mixed gas containing nitrous oxide.

[0031] The air inlet may be connected to an air inlet valve, and the air outlet may be connected to an air outlet valve.

[0032] The reaction chamber may be provided with a quartz glass window for allowing light to irradiate the copper-based supported catalyst. Further, the quartz glass window may be provided on the top surface of the reaction chamber.

[0033] The copper-based loaded catalyst can be coated on a glass fiber membrane. A catalyst support platform can be provided in the reaction chamber to support the glass fiber membrane coated with the copper-based loaded catalyst. The catalyst support platform has a hollow structure connected to the air inlet, and the glass fiber membrane coated with the copper-based loaded catalyst is located at one end of the hollow structure. The nitrous oxide or the mixed gas containing nitrous oxide can enter the hollow structure through the air inlet, and then pass through the glass fiber membrane coated with the copper-based loaded catalyst. Such a design facilitates the complete passage of gas through the catalyst in a continuous flow reaction, thereby achieving effective contact between the reactant and the catalyst. In some embodiments, the glass fiber membrane coated with the copper-based loaded catalyst is located at the top of the hollow structure, which facilitates the illumination of light through a quartz glass window onto the copper-based loaded catalyst.

[0034] The circulating medium passing through the barrier layer can create a desired temperature environment for the reaction chamber, and the circulating medium can be water, etc. The circulating medium can flow in the barrier layer in a direction such as bottom-in and top-out.

[0035] A thermocouple can be inserted into the thermocouple insertion hole to detect the surface temperature of the copper-based supported catalyst.

[0036] The present invention has the advantages of precise control, simple process, convenient operation, good stability, clean and sustainable reaction system, etc. It can be widely used in the degradation of various pollutants and catalytic conversion systems of other substances, and has good practical application prospects.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] 1. It has achieved the goal of using light as the only energy input source to drive the catalytic degradation of nitrous oxide into nitrogen and oxygen, which are harmless to the environment, thus achieving the control of greenhouse gases. At the same time, the catalytic technology is green and economical, with low energy consumption.

[0039] 2. The full spectrum including ultraviolet, visible and infrared can be effectively utilized to achieve light-driven photothermal synergistic catalysis to enhance reaction activity.

[0040] 3. The catalyst achieves precise control of low-valent copper sites, simple process, good performance, and good reaction stability, and can be widely used in various catalytic reaction systems.

[0041] 4. This method of precisely regulating the valence properties of active sites can be used in other catalytic fields in a targeted manner based on reaction characteristics.

[0042] 5. Stainless steel reactors with interlayers and gas ports can be used for batch reactions and continuous flow reactions. Compared with glass / quartz reactors, they have slower heat diffusion and help achieve light-driven thermal and light synergy. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 The ultraviolet-visible diffuse reflectance spectrum (UV-visDRS) of the Cu-supported catalyst prepared in Example 1 and the carrier used is shown in FIG.

[0044] Figure 2 The high-resolution transmission electron microscopy (HRTEM) image of the Cu-supported catalyst prepared in Example 1 and its element distribution (Mapping) diagram are shown.

[0045] Figure 3 This is the X-ray photoelectron spectroscopy (XPS) graph of the Cu-supported catalyst prepared in Example 1.

[0046] Figure 4 This is the in-situ XPS graph of the support metal in the Cu-supported catalyst prepared in Example 1.

[0047] Figure 5 This is the in-situ XPS graph of copper in the Cu-supported catalyst prepared in Example 1.

[0048] Figure 6 Schematic diagram of the structure of the reaction chamber of the stainless steel photocatalytic reactor used in the specific embodiment.

[0049] Figure 7 This is a 4-h activity diagram of the Cu-supported catalyst prepared in Example 1 in a batch reaction.

[0050] Figure 8 This is the N2O circulation reaction diagram of the Cu-supported catalyst Cu / TiO2 prepared in Example 1 in a batch reaction.

[0051] Figure 9 This is a graph showing the N2O degradation results of the Cu-supported catalyst Cu / TiO2 prepared in Example 1 under different N2O concentrations in a batch reaction for 4 hours.

[0052] Figure 10 This is a graph showing the N2O degradation results of the Cu-supported catalyst Cu / TiO2 prepared in Example 1 under different conditions in a batch reaction for 2 hours.

[0053] Figure 11 Graphs showing N2O conversion and product generation in the continuous flow reaction of the Cu-supported catalyst Cu / TiO2 and chromatographic data in Example 2.

[0054] Figure 12 This is the activity diagram of the Cu-supported catalyst Cu / TiO2 in Example 2 through 10 stages of continuous flow reaction in series.

[0055] Figure 13 This is a graph showing the N2O degradation results of the Cu-supported catalyst Cu / TiO2 in Example 2 under different conditions in a continuous flow reaction for 120 minutes. DETAILED DESCRIPTION

[0056] The present invention will be further described below in conjunction with the accompanying drawings and specific examples. It should be understood that these examples are intended to illustrate the present invention and are not intended to limit the scope of the invention. The operating methods in the following examples where specific conditions are not specified are generally performed under conventional conditions or as recommended by the manufacturer. Unless otherwise indicated, the raw materials and reagents used in the following examples are commercially available products or can be prepared by known methods.

[0057] Example 1:

[0058] (1) Preparation of catalyst:

[0059] 1g of carriers TiO2, ZnO and WO3 were dispersed in 100mL of deionized water respectively, and after ultrasonication for 30min, stirring was continued until the above carriers were completely dispersed. Copper nitrate solution was added dropwise under stirring, and then stirred at 80°C until the aqueous solution was evaporated; the above mixture was then placed in an oven at 80°C for overnight drying; the dried material was placed in a muffle furnace and uniformly heated to 500°C at a rate of 5°C / min, calcined for 3 hours, and then cooled to room temperature to obtain Cu-loaded catalysts Cu / TiO2, Cu / ZnO and Cu / WO3, where the Cu loading amount was 8wt%.

[0060] Figure 1 The UV-vis DRS diagram of the Cu-supported catalyst and the carrier used in this example shows that Cu loading broadens the light response region.

[0061] Figure 2 HRTEM photos and mapping diagrams of the Cu-supported catalysts prepared in this example confirm the uniform distribution of Cu on the three supports.

[0062] Figure 3 The XPS diagram of the Cu supported catalyst prepared in this example shows that the order of metal electronegativity is: W>Cu>Zn>Ti. Compared with other catalysts, Cu has a stronger electronegativity than Ti, which makes Cu in Cu / TiO2 + The highest proportion.

[0063] Figure 4 and Figure 5 The in-situ XPS graph of the Cu-supported catalyst prepared in this example. Compared with the dark condition, light promotes the charge transfer process, which increases the low-valent Cu content in Cu / TiO2 and Cu / ZnO. + / Cu 2+ The ratio increased from 0.49 in dark conditions to 0.57 in light conditions and from 0.33 in dark conditions to 0.37 in light conditions. The content of low-valent Cu in Cu / WO3 decreased, of which Cu + / Cu 2+ The ratio changed from 0.21 in dark conditions to 0.18 in light conditions.

[0064] (2) Intermittent light-driven N2O degradation performance test:

[0065] A stainless steel photocatalytic reactor is used. Stainless steel photocatalytic reactors have slow heat diffusion and can achieve synergistic effects of heat and light driven by light as the sole energy input source. The stainless steel photocatalytic reactor includes a reaction chamber, and a partition is set outside the reaction chamber to allow circulation of a circulating medium. Under normal circumstances, the partition does not need to be filled with circulating medium. When necessary, the partition can be filled with circulating medium to create the required temperature environment for the reaction chamber. The circulating medium can be water, etc. The circulating medium flows from the bottom in and out from the top. Figure 6 The reaction chamber has an air inlet, an air outlet and a thermocouple insertion hole. The Cu-loaded catalyst is placed in the reaction chamber. The air inlet is used to receive nitrous oxide or a mixture containing nitrous oxide. The air inlet is connected to the air inlet valve, and the air outlet is connected to the air outlet valve. The reaction chamber has a quartz glass window for irradiating light onto the Cu-loaded catalyst. The quartz glass window is arranged on the top surface of the reaction chamber. The Cu-loaded catalyst is coated on the glass fiber membrane. A catalyst support platform is provided in the reaction chamber to support the glass fiber membrane coated with the Cu-loaded catalyst. The catalyst support platform has a hollow structure connected to the air inlet, and the glass fiber membrane coated with the Cu-loaded catalyst is located at the top of the hollow structure. Nitrous oxide or a mixture containing nitrous oxide can enter the hollow structure through the air inlet and then pass through the glass fiber membrane coated with the Cu-loaded catalyst. A thermocouple is inserted into the thermocouple insertion hole to detect the surface temperature of the Cu-loaded catalyst.

[0066] The above-mentioned stainless steel photocatalytic reactor was used. The effective volume of the reaction chamber of the stainless steel photocatalytic reactor was 50 mL. The air inlet and the air outlet were kept unobstructed. N2O with a concentration of 10 vol% (the carrier gas was argon) was introduced into the stainless steel photocatalytic reactor containing 30 mg of Cu-supported catalyst at a flow rate of 30 mL / min. The introduction was continued for 60 min. Other gases in the reaction chamber were discharged until the reaction chamber was filled with 10 vol% N2O. The air inlet and the air outlet were closed to seal the reaction chamber. Then, a xenon lamp was used as the light source at a light intensity of 515.9 mW cm -2 The N2O degradation performance was tested under the full spectrum of the reaction for 2h, 4h or 6h. The results of the reaction for 4h were as follows. Figure 7 Cu / TiO2 achieved 47.6% N2O conversion after 4 h of reaction, and the reaction kinetic constant (k) was 0.15 h -1 , which is 1.6 to 25.8 times the activity reported previously (see Table 1). The N2O conversion rate of 59.6% was achieved after 6 h of reaction, which is much higher than the previous reports. Figure 8 The N2O conversion rate remained stable during the reaction of 5 cycles with a total of 30 hours.

[0067] Figure 9The Cu / TiO2 catalyst prepared in this example demonstrates the N2O degradation results of a batch reaction using Cu / TiO2 at different N2O concentrations over a 4-hour reaction. The experimental procedures were identical to those for the 10 vol% N2O batch reaction, differing only in varying the N2O concentrations to 0.97 vol%, 1.8 vol%, and 5 vol% (with argon as the carrier gas). Cu / TiO2 consistently achieved N2O conversions of nearly 40% or greater over a 4-hour reaction at various N2O concentrations, outperforming existing studies.

[0068] Table 1

[0069]

[0070] In Table 1, the a The kinetic constants are derived from literature reports, and the others are kinetic constants calculated based on the activity in the literature.

[0071] Figure 10 The results of N2O degradation of the Cu-supported catalyst Cu / TiO2 prepared in this embodiment under different conditions in a batch reaction for 2 hours are shown. Among them, UV-vis-IR represents the full spectrum test described above, and the catalyst surface temperature can reach 260°C; UV-vis means referring to the test process described above, but filtering out infrared light (which can be achieved by adding a filter to the light outlet of the xenon lamp, and similar filtering operations will not be repeated below), and the catalyst surface temperature is 137°C. Since infrared light does not make a photocatalytic contribution to the degradation of nitrous oxide, this condition can illustrate the thermal catalytic effect in the method of the present invention compared with UV-vis-IR; vis-IR 1 The test process described above is referred to, but the ultraviolet light is filtered out. The catalyst surface temperature is 245 ° C. The catalyst surface temperature is not much different from the UV-vis-IR condition, but the N2O degradation rate is significantly reduced, which illustrates the ultraviolet catalytic effect of the method of the present invention; vis-IR 2 and vis-IR 1 The only difference is that the light intensity is increased to 652.9mW / cm 2 , so that the catalyst surface temperature reaches the same level as UV-vis-IR, and the N2O degradation rate is compared with vis-IR 1 Although it has been improved, it still cannot reach the UV-vis-IR level, which illustrates the synergistic effect of ultraviolet photocatalysis and thermal catalysis in the method of the present invention; IR 1 and vis-IR 1 The only difference is that the visible light is further filtered out, and the catalyst surface temperature is 173℃; IR 2 The only difference from UV-vis-IR is that infrared lamps are used instead of xenon lamps. Infrared lamps provide heat source to make the catalyst surface temperature reach the same level as UV-vis-IR and vis-IR.2 Consistent, IR 2 The corresponding N2O degradation rate and UV-vis-IR and vis-IR 2 The corresponding N2O degradation rates are compared to illustrate the effects of ultraviolet and visible light catalysis in the method of the present invention.

[0072] Example 2:

[0073] The Cu-supported catalyst Cu / TiO2 was prepared according to Example 1 and subjected to a continuous streamer-driven N2O degradation performance test:

[0074] The same stainless steel photocatalytic reactor as in Example 1 was used, with the air inlet and outlet kept unobstructed. 10 vol% N2O (carrier gas: argon) was introduced into the stainless steel photocatalytic reactor containing 30 mg of Cu-supported catalyst at a flow rate of 30 mL / min. The introduction was continued for 60 min, and other gases in the reaction chamber were discharged until the reaction chamber was filled with 10 vol% N2O. 10 vol.% N2O (carrier gas: argon) was then continued to be introduced at a flow rate of 5 mL / min. Then, at a light intensity of 515.9 mW / cm -2 The degradation performance of N2O was tested within 120 minutes under the full spectrum of Figure 11 As shown in Figure 2, the N2O degradation performance first increases and then stabilizes as the light intensity gradually stabilizes. During the reaction, only N2, O2 and N2O are monitored, and no other nitrogen oxide by-products are produced. The formation rate of N2 is consistent with the reaction rate of N2O, indicating that no nitrogen oxide by-products are produced in this process. The results of the 10-stage continuous flow reaction are shown in Figure 2. Figure 12 , ultimately achieving 31.9% N2O conversion.

[0075] Figure 13 The results of N2O degradation of Cu / TiO2 supported catalyst in this embodiment under different light intensity stabilization conditions in continuous flow reaction are shown. Among them, UV-vis-IR represents the full spectrum test described above, and the catalyst surface temperature can reach 260℃; UV-vis 1 The test process described above is referred to, but infrared light is filtered out, and the catalyst surface temperature is 138°C. Since infrared light does not make a photocatalytic contribution to the degradation of nitrous oxide, this condition can illustrate the thermal catalytic effect in the method of the present invention compared with UV-vis-IR; vis-IR 1 The test process described above is referred to, but the ultraviolet light is filtered out. The catalyst surface temperature is 242 ° C. The catalyst surface temperature is not much different from the UV-vis-IR condition, but the N2O degradation rate is significantly reduced, which illustrates the ultraviolet catalytic effect of the method of the present invention; vis-IR 2 and vis-IR 1The only difference is that the light intensity is increased to 652.9mW / cm 2 , so that the catalyst surface temperature reaches the same level as UV-vis-IR, and the N2O degradation rate is compared with vis-IR 1 Although it has been improved, it still cannot reach the level of UV-vis-IR, which illustrates the synergistic effect of ultraviolet photocatalysis and thermal catalysis in the method of the present invention; IR and vis-IR 1 The only difference is that the visible light is further filtered out, and the catalyst surface temperature is 172℃; UV-vis 2 and UV-vis 1 The only difference is that cooling circulating water is continuously introduced into the interlayer to reduce the catalyst surface temperature to 97°C.

[0076] In addition, it should be understood that after reading the above description of the present invention, those skilled in the art may make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the claims attached to this application.

Claims

1. A method for achieving efficient light-driven nitrous oxide degradation using a copper-based supported catalyst, characterized in that: include: Under light, nitrous oxide or a mixed gas containing nitrous oxide is contacted with the copper-based supported catalyst for reaction, and nitrous oxide is degraded by photothermal synergy with light as the only energy input; The light used for the illumination includes visible light and / or ultraviolet light; The carrier of the copper-based supported catalyst is TiO2; During the contact reaction, the surface temperature of the copper-based supported catalyst is greater than 100°C.

2. The method according to claim 1, characterized in that The light used for the illumination also includes infrared light.

3. The method according to claim 1, characterized in that The light intensity of the illumination is 500-700 mW / cm 2 .

4. The method according to claim 1, wherein Except for nitrous oxide, all the mixed gases are inert gases that do not participate in the reaction.

5. The method according to claim 1, wherein The copper loading amount of the copper-based supported catalyst is 0.5 wt% to 10 wt%.

6. The method according to claim 1, characterized in that The copper in the copper-based supported catalyst is Cu + and Cu 2+ Exists in mixed forms.

7. The method according to claim 1, characterized in that The preparation method of the copper-based supported catalyst comprises: adding a Cu(II) precursor solution dropwise to a TiO2 dispersion under stirring, maintaining stirring after the addition is completed and heating to evaporate the solvent, and drying and calcining the resulting mixture to obtain the copper-based supported catalyst.

8. The method according to claim 7, characterized in that The calcination temperature is 500±5° C., the calcination holding time is 3 to 4 hours, and the calcination heating rate is 5 to 10° C. / min.

9. The method according to claim 1, characterized in that The method is a combination of one or more of batch and continuous flow; During the contact reaction, the nitrous oxide or the mixed gas containing nitrous oxide is in a static or fluid state.

10. The method according to claim 1, characterized in that The method uses a stainless steel photocatalytic reactor; The stainless steel photocatalytic reactor comprises a reaction chamber, a barrier layer for admitting a circulating medium is provided on the outside of the reaction chamber, the reaction chamber is provided with an air inlet, an air outlet, and a thermocouple insertion hole, the copper-based supported catalyst is placed in the reaction chamber, and the air inlet is used to receive the nitrous oxide or the mixed gas containing nitrous oxide; The air inlet is connected to the air inlet valve, and the air outlet is connected to the air outlet valve; The reaction chamber is provided with a quartz glass window for allowing light to irradiate the copper-based supported catalyst; the quartz glass window is provided on the top surface of the reaction chamber; The copper-based supported catalyst is coated on a glass fiber membrane; a catalyst support platform is provided in the reaction chamber for supporting the glass fiber membrane coated with the copper-based supported catalyst; the catalyst support platform has a hollow structure connected to the air inlet, the glass fiber membrane coated with the copper-based supported catalyst is located at one end of the hollow structure, and the nitrous oxide or the mixed gas containing nitrous oxide enters the hollow structure through the air inlet and then passes through the glass fiber membrane coated with the copper-based supported catalyst; The circulating medium is water; The circulating medium flows in the barrier layer in a direction of bottom-in and top-out; A thermocouple is inserted into the thermocouple insertion hole to detect the surface temperature of the copper-based supported catalyst.

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