Ordered wavy microporous rare earth-based catalyst for simultaneous denitration and VOCs removal and preparation method thereof

Abstract

The present invention discloses an ordered wavy microporous rare earth catalyst for simultaneous denitrification and VOCs removal and its preparation method. The catalyst uses a light rare earth composite oxide of europium, lanthanum and samarium as the active component, cerium oxide as the carrier, and an amino acid-based amphoteric surfactant. The catalyst is acid-guided and enhanced in the presence of an organic modifier, and is synthesized by a one-step supercritical hydrothermal method. The active component is uniformly dispersed on the carrier, forming ordered wavy channels on the surface. The catalyst has excellent synergistic catalytic performance and strong resistance to water-sulfur poisoning, and can achieve NO removal under low temperature conditions. x , VOCs synergistic catalytic removal, and NO x , VOCs conversion rates are both higher than 90%, which effectively simplifies the treatment process of industrial tail gas purification, improves the purification efficiency of the reactor, and reduces the cost of flue gas treatment.

Description

Technical Field

[0001] The invention relates to an ordered wave microporous rare earth-based catalyst for simultaneous denitration and removal of VOCs and a preparation method thereof, and belongs to the field of industrial flue gas purification. Background Art

[0002] NO x It is one of the main sources of air pollution and poses a huge threat to human health and the ecological environment. Dioxins are a general term for two types of tricyclic aromatic organic compounds and are the most carcinogenic substances discovered so far. Excessive intake by humans can produce irreversible teratogenic, carcinogenic and mutagenic effects. Industrial flue gas has a complex composition, including dust, heavy metals, SO x 、NO x As well as VOCs, they have become important factors restricting the green development of the industry. In recent years, environmental protection laws and regulations have gradually improved, and the emission standards for conventional pollutants have become more stringent. At the same time, VOCs are of various types and volatile. Many VOCs have high photochemical reactivity and can easily become precursors of ozone and fine particulate matter in the atmosphere. There are also many VOCs that are pathogenic. While polluting the environment, they also bring harm to human health and life. Therefore, the reduction of VOCs has also become an important topic in the current environmental air pollution control. At present, the control of these pollutants generally adopts a separate removal method, which results in a large area of ​​factory flue gas treatment equipment and high control costs. Therefore, research and development of a method that can convert NO x The catalyst that can remove VOCs and VOCs at the same time can greatly save equipment and operating costs and has great market prospects.

[0003] Among the existing denitrification patents, Patent CN201510043079.0 uses a furnace spinning process to make RP-CHOP denitrification catalyst fibers, which are then mixed with SCR denitrification catalyst raw materials to produce ultra-thin SCR denitrification catalysts. Patent CN202111531635.0 uses SiC as a carrier to load samarium metal on a manganese-cerium metal catalyst to obtain a denitrification catalyst with Sm as the active ingredient, so that the gas-phase reactants can be better adsorbed on the active sites on the surface of the denitrification catalyst, thereby improving the catalytic activity. Patent CN202010680304.2 prepares a low-temperature SCR denitrification catalyst with red mud as the main raw material. The reaction temperature required for the denitrification catalyst is relatively low and has good low-temperature catalytic activity. Patent CN202111529860.0 expands the active temperature window of the denitrification catalyst by loading high-entropy oxides on TiO2, improves the low-temperature activity and catalytic performance of the denitrification catalyst, and achieves NO at 200°C. xHowever, the current industrial flue gas is characterized by the complex nature of multiple pollutants. A simple denitrification catalyst is difficult to meet the process requirements for the coordinated removal of multiple pollutants under complex working conditions, resulting in a long flue gas purification process and high flue gas purification costs. At the same time, the flue gas temperature in the non-power industry is low, and conventional vanadium-titanium system denitrification catalysts are difficult to meet the requirements of NO under low temperature conditions. x The need for high-efficiency removal.

[0004] Among the existing denitration and de-VOCs catalyst patents, patent CN202111049719.0 uses nano-titanium dioxide as a catalyst carrier, cobalt oxide, manganese oxide, and copper oxide as active substances, and adopts a step-by-step precipitation method to prepare a denitration, de-dioxin, and de-VOCs integrated catalyst. Patent CN202211448628.9 uses a wet method to simultaneously / synergistically treat NO x , NH3 and VOCs, will contain NO x , NH3 and VOCs flue gas or waste gas is discharged after absorption and purification in an absorption tower, and the absorption liquid contains a composite oxidant. Patent CN202011297756.9 discloses a regeneration catalyst that can achieve simultaneous denitration and removal of VOCs and CO and a preparation method thereof. The deactivated catalyst is cleaned by aeration bubbling and placed in a Ce / Co active system modified loading liquid. After loading under room temperature conditions, it is dried and calcined to obtain a regeneration catalyst with the function of achieving simultaneous denitration and removal of VOCs and CO. Patent CN202211254540.3 impregnates a pretreated metal honeycomb carrier into a slurry made by mixing catalyst powder and aluminum sol, and then dries and calcines it to obtain a synergistic denitration and removal of VOCs catalyst. Patent CN202210744878.0 mixes a TiO2 / Ce2S3 composite with a vanadium source and a molybdenum source to form a mixture, and then dries and calcines it to obtain a denitration and removal of VOCs catalyst, which can achieve NO in the range of 200-260°C. x The conversion rate is ≥80%, and the VOCs catalytic oxidation conversion rate is ≥70%. Patent CN202111438981.4 uses a co-precipitation method to precipitate and calcine the active metal source containing Cu, Ce, and Ti under alkaline conditions to obtain a catalyst for VOCs and NO in sulfur-containing flue gas. x Patent CN202210452380.7 uses an adaptive reaction method to obtain a composite oxide catalyst for simultaneous removal of VOCs and NO in medium and low temperature flue gas. x The composite manganese oxide catalyst for simultaneous removal shows excellent VOCs and NO removal under medium and low temperature flue gas conditions. xSynchronous removal performance. The catalysts obtained by current conventional catalyst preparation methods (co-precipitation, impregnation, and distributed precipitation) generally do not have a special morphology. As a result, under complex flue gas conditions (high water content, VOCs content, and low temperature), the catalysts exhibit insufficient synergistic removal activity on the one hand, and are prone to poisoning and deactivation on the other hand, which seriously affects the catalyst market application. At the same time, conventional methods usually use multiple steps to prepare the catalyst, resulting in insufficient catalyst preparation efficiency and high production costs. Summary of the Invention

[0005] The purpose of the present invention is to address the current status and problems of existing industrial flue gas denitrification, deVOCs removal processes and catalysts, and to propose a rare earth-based catalyst with an ordered wavy microporous structure that has the function of simultaneous denitrification and deVOCs removal. Another purpose of the present invention is to provide a method for preparing the above-mentioned ordered wavy microporous rare earth-based catalyst.

[0006] A rare earth-based catalyst for simultaneous denitrification and VOCs removal using ordered wavy microporous structures. The catalyst uses light rare earth composite oxides of europium, lanthanum, and samarium as active components, cerium oxide as a carrier, and is based on an amino acid-type amphoteric surfactant. It is enhanced by acid solution guidance and synthesized using a one-step supercritical hydrothermal method in the presence of an organic modifier.

[0007] In the technical solution of the present invention, based on the mass of the carrier, the mass percentage of the active component is 2-10%; the mass ratio of europium oxide: lanthanum oxide: samarium oxide in the active component is 5: (2-5): (1-2).

[0008] In the technical solution of the present invention, the mass ratio of carrier: surfactant: acid solution: organic modifier is: 10: (0.1-0.5): (0.1-0.2): (0.05-0.1);

[0009] Wherein, the surfactant is sodium laurylaminopropionate; the acid solution is a hydrochloric acid solution with a mass fraction of 5-10%; and the organic modifier is n-hexanal or n-valeraldehyde.

[0010] A method for preparing the above-mentioned ordered wavy microporous rare earth-based catalyst for simultaneous denitration and VOCs removal is as follows:

[0011] (1) Preparation of active component precursor solution

[0012] Adding europium salt, lanthanum salt and samarium salt into deionized water and stirring to obtain an active component precursor solution;

[0013] (2) Supercritical hydrothermal reaction

[0014] Transferring the cerium salt, surfactant, acid solution, organic modifier and the active component precursor ion solution prepared in step (1) to a supercritical hydrothermal reactor for supercritical hydrothermal reaction;

[0015] (3) Final formation of the catalyst

[0016] The solid-liquid mixture obtained after the reaction in step (2) is filtered to collect the solid product, and then placed in a forced air drying oven to keep warm and dry to obtain the desired catalyst.

[0017] In the above preparation method: the europium salt described in step (1) is europium nitrate or europium trichloride; the lanthanum salt is holmium nitrate pentahydrate; and the samarium salt is samarium nitrate or samarium chloride.

[0018] In the above preparation method: the mass ratio of the total mass of the europium salt, lanthanum salt and samarium salt described in step (1) to deionized water is 1:60-120.

[0019] In the above preparation method: the cerium salt described in step (2) is cerium nitrate hexahydrate or cerium chloride heptahydrate.

[0020] In the above preparation method: the supercritical hydrothermal reaction temperature in step (2) is 400-500° C., and the reaction time is 15-30 min.

[0021] In the above preparation method: the drying temperature in step (3) is 100-120° C., and the drying time is 2-4 hours.

[0022] In the technical solution of the present invention: the application of the rare earth-based catalyst in denitration and VOCs removal.

[0023] The experimental conditions and results for evaluating the catalyst activity of the present invention are as follows: 0.5 mL of a 40-60 mesh catalyst was poured into a quartz tube with an inner diameter of 8 mm, secured with quartz wool and wire mesh, and placed in a tube furnace. The actual temperature of the catalytic reaction was adjusted by controlling the heating temperature of the tube furnace. Toluene was used as a representative VOC substance, and laboratory gas was used to simulate flue gas. The inlet components were: NO (500 ppm), NH3 (500 ppm), O2 (11 vol.%), toluene (500 ppm), and the remainder was N2. The total gas flow rate was 500 mL / min. The NO concentration was measured using a Laoying 3021 portable carbon emission monitor, and the toluene concentration was measured using a Trace 1300ISQ7000 gas chromatograph-mass spectrometer. At 100°C, after 5 minutes, the NO removal efficiency was 100%, and the toluene removal efficiency was over 95%.

[0024] Beneficial effects of the present invention:

[0025] In view of the high concentration of pollutants (NO x, VOCs, etc.) purification generally adopts a separate removal method, which leads to problems such as large floor space occupied by factory flue gas treatment equipment and high management costs. At the same time, the existing denitrification and de-VOCs catalyst preparation methods (step-by-step precipitation, impregnation, coating, etc.) have the disadvantages of long preparation process flow and low preparation efficiency, and the catalytic active components are unevenly dispersed on the carrier. At the same time, the synergistic removal catalyst has poor resistance to water sulfur poisoning at low temperatures. Therefore, the present invention innovatively develops a method that can remove NO x The ordered wavy microporous rare earth-based catalyst can remove NO and VOCs simultaneously, so that the flue gas can be removed by the catalyst. x , and VOCs are removed simultaneously, and catalytic preparation is achieved in one step, which greatly saves equipment and operating costs.

[0026] The main basis is:

[0027] Rare earth elements such as lanthanum (La) and cerium (Ce) have unique 4f electron layer structures. When their oxides are used in combination, they have a significant synergistic effect, greatly improving the low-temperature catalytic performance of the catalyst. The surfactant sodium dodecylaminopropionate can be converted into sodium dodecylaminopropionate hydrochloride in a hydrochloric acid medium. 12 H 25 N + H2CH2CH2COOH)Cl - 〕, which is a cationic surfactant soluble in water, effectively enhancing the bonding effect between the catalytic active component and the carrier; using n-hexanal or n-valeraldehyde as an organic modifier, a chemical bond is formed between the CeO2 surface and the modifier, which can change the surface property of the CeO2 particles from hydrophilic to hydrophobic, thereby improving the catalyst's ability to resist water poisoning; under overall regulation, the rare earth-based denitrification catalyst synthesized by supercritical hydrothermal method has an ordered wavy microporous structure, exposing more reactive sites, enhancing the adsorption effect on pollutants, and improving the catalytic performance of the catalyst. The successful application of the present invention can not only achieve NO x , VOCs are removed synergistically, while improving the production efficiency of rare earth-based catalysts, thus bringing huge economic, environmental and social benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a scanning electron microscope image of the catalyst prepared in Example 1.

[0029] Figure 2 The performance diagram of NO removal of the catalysts prepared in Examples 1-3 and Comparative Examples 1-3.

[0030] Figure 3 The performance diagram of the catalysts prepared in Examples 1-3 and Comparative Examples 1-3 for removing toluene is shown. DETAILED DESCRIPTION

[0031] The present invention will be further described below with reference to the following examples, but the scope of protection of the present invention is not limited thereto: Example 1

[0032] 1. Preparation of rare earth-based catalysts

[0033] (1) Preparation of active component precursor solution

[0034] 0.781 g of europium trichloride, 0.399 g of lanthanum nitrate, and 0.191 g of samarium nitrate were added to 109.66 g of deionized water and stirred at room temperature to obtain an active component precursor solution;

[0035] (2) Supercritical hydrothermal reaction

[0036] The mass percentage of the active component is 6% based on the mass of the carrier. 25.229g of cerium nitrate, 0.5g of sodium dodecylaminopropionate, 0.2g of a 10% hydrochloric acid dilute solution, 0.1g of n-hexanal, and the active component precursor ion solution prepared in step (1) are transferred to a supercritical hydrothermal reactor and subjected to a hydrothermal reaction at 450°C for 25 minutes, wherein the mass ratio of the carrier: surfactant: acid solution: organic modifier is 10:0.3:0.2:0.1.

[0037] (3) Final formation of the catalyst

[0038] The solid-liquid mixture obtained after the reaction in step (2) was filtered to collect the solid product, and then placed in a forced air drying oven at 100° C. for 4 hours to obtain the desired catalyst, wherein the mass ratio of europium oxide: lanthanum oxide: samarium oxide in the active components was 5:2:1.

[0039] 2. Activity Test Results

[0040] Take 0.5mL of 40-60 mesh catalyst, pour it into a quartz tube with an inner diameter of 8mm, fix it with quartz wool and wire mesh, place the quartz tube in a tube furnace, and adjust the actual temperature of the catalytic reaction by controlling the heating temperature of the tube furnace. Use toluene as a representative substance of VOCs, use laboratory gas to simulate flue gas, the intake components are: NO (500ppm), NH3 (500ppm), O2 (11vol.%), toluene (500ppm), and the rest are N2. The total gas flow rate is 500mL / min. Use Laoying 3021 portable carbon emission monitor to test NO concentration, and use Trace 1300ISQ 7000 gas chromatograph-mass spectrometer to test toluene concentration. Figure 2 and Figure 3 As shown, the test results show that the NO removal efficiency is 100% and the toluene removal efficiency is 97.8% after 5 minutes at 100°C.

[0041] Example 2

[0042] 1. Preparation of rare earth-based catalysts

[0043] (1) Preparation of active component precursor solution

[0044] 0.833 g of europium trichloride, 0.638 g of lanthanum nitrate, and 0.335 g of samarium chloride were added to 108.34 g of deionized water and stirred at room temperature to obtain an active component precursor solution;

[0045] (2) Supercritical hydrothermal reaction

[0046] Based on the mass of the carrier, the mass percentage of the active component is 10%. 20.183g of cerium nitrate, 0.08g of sodium dodecylaminopropionate, 0.08g of a 5% hydrochloric acid dilute solution, 0.04g of n-hexanal, and the active component precursor ion solution prepared in step (1) are successively transferred to a supercritical hydrothermal reactor and subjected to hydrothermal reaction at 400°C for 30 minutes, wherein the mass ratio of carrier: surfactant: acid solution: organic modifier is 10:0.1:0.1:0.05.

[0047] (3) Final formation of the catalyst

[0048] The solid-liquid mixture obtained after the reaction in step (2) is filtered to collect the solid product, and then placed in a forced air drying oven at 120° C. for 2 hours to obtain the desired catalyst, wherein the mass ratio of europium oxide: lanthanum oxide: samarium oxide in the active components is 5:3:2.

[0049] 2. Activity Test Results

[0050] Take 0.5mL of 40-60 mesh catalyst, pour it into a quartz tube with an inner diameter of 8mm, fix it with quartz wool and wire mesh, place the quartz tube in a tube furnace, and adjust the actual temperature of the catalytic reaction by controlling the heating temperature of the tube furnace. Use toluene as a representative substance of VOCs, use laboratory gas to simulate flue gas, the intake components are: NO (500ppm), NH3 (500ppm), O2 (11vol.%), toluene (500ppm), and the rest are N2. The total gas flow rate is 500mL / min. Use Laoying 3021 portable carbon emission monitor to test NO concentration, and use Trace 1300ISQ 7000 gas chromatograph-mass spectrometer to test toluene concentration. Figure 2 and Figure 3 As shown, the test results show that the NO removal efficiency is 100% and the toluene removal efficiency is 95.4% after 5 minutes at 100°C.

[0051] Example 3

[0052] 1. Preparation of rare earth-based catalysts

[0053] (1) Preparation of active component precursor solution

[0054] 0.160 g of europium nitrate, 0.190 g of lanthanum chloride, and 0.070 g of samarium chloride were added to 44.075 g of deionized water and stirred at room temperature to obtain an active component precursor solution;

[0055] (2) Supercritical hydrothermal reaction

[0056] Based on the mass of the carrier, the mass percentage of the active component is 2%. 21.647g of cerium chloride, 0.3g of sodium dodecylaminopropionate, 0.2g of a dilute hydrochloric acid solution with a mass fraction of 8%, 0.1g of n-valeraldehyde, and the active component precursor ion solution prepared in step (1) are successively transferred to a supercritical hydrothermal reactor and hydrothermally reacted at 500°C for 15 minutes, wherein the mass ratio of carrier: surfactant: acid solution: organic modifier is 10:0.5:0.2:0.1.

[0057] (3) Final formation of the catalyst

[0058] The solid-liquid mixture obtained after the reaction in step (2) is filtered to collect the solid product, and then placed in a forced air drying oven at 120° C. for 3 hours to obtain the desired catalyst, wherein the mass ratio of europium oxide: lanthanum oxide: samarium oxide in the active components is 5:5:2.

[0059] 2. Activity Test Results

[0060] Take 0.5mL of 40-60 mesh catalyst, pour it into a quartz tube with an inner diameter of 8mm, fix it with quartz wool and wire mesh, place the quartz tube in a tube furnace, and adjust the actual temperature of the catalytic reaction by controlling the heating temperature of the tube furnace. Use toluene as a representative substance of VOCs, use laboratory gas to simulate flue gas, the intake components are: NO (500ppm), NH3 (500ppm), O2 (11vol.%), toluene (500ppm), and the rest are N2. The total gas flow rate is 500mL / min. Use Laoying 3021 portable carbon emission monitor to test NO concentration, and use Trace 1300ISQ 7000 gas chromatograph-mass spectrometer to test toluene concentration. Figure 2 and Figure 3 As shown, the test results show that the NO removal efficiency is 100% and the toluene removal efficiency is 96.6% after 5 minutes at 100°C.

[0061] Comparative Example 1

[0062] 1. Preparation of rare earth-based catalysts

[0063] During the catalyst preparation process, europium salt, lanthanum salt and samarium salt were not added, and other procedures were the same as in Example 1.

[0064] 2. Activity Test Results

[0065] Take 0.5mL of 40-60 mesh catalyst, pour it into a quartz tube with an inner diameter of 8mm, fix it with quartz wool and wire mesh, place the quartz tube in a tube furnace, and adjust the actual temperature of the catalytic reaction by controlling the heating temperature of the tube furnace. Use toluene as a representative substance of VOCs, use laboratory gas to simulate flue gas, the intake components are: NO (500ppm), NH3 (500ppm), O2 (11vol.%), toluene (500ppm), and the rest are N2. The total gas flow rate is 500mL / min. Use Laoying 3021 portable carbon emission monitor to test NO concentration, and use Trace 1300ISQ 7000 gas chromatograph-mass spectrometer to test toluene concentration. Figure 2 and Figure 3 As shown, the catalytic performance decreased because the carrier did not load the active components of the composite oxide. The test results showed that the NO removal efficiency was 40.7% and the toluene removal efficiency was 18.4% after 5 minutes at 100°C.

[0066] Comparative Example 2

[0067] 1. Preparation of rare earth-based catalysts

[0068] During the supercritical hydrothermal reaction, sodium lauryl aminopropionate was not added as a surfactant, and the other conditions were the same as in Example 2.

[0069] 2. Activity Test Results

[0070] Take 0.5mL of 40-60 mesh catalyst, pour it into a quartz tube with an inner diameter of 8mm, fix it with quartz wool and wire mesh, place the quartz tube in a tube furnace, and adjust the actual temperature of the catalytic reaction by controlling the heating temperature of the tube furnace. Use toluene as a representative substance of VOCs, use laboratory gas to simulate flue gas, the intake components are: NO (500ppm), NH3 (500ppm), O2 (11vol.%), toluene (500ppm), and the rest are N2. The total gas flow rate is 500mL / min. Use Laoying 3021 portable carbon emission monitor to test NO concentration, and use Trace 1300ISQ 7000 gas chromatograph-mass spectrometer to test toluene concentration. Figure 2 and Figure 3 As shown, due to the lack of addition of dodecylaminopropionic acid as a surfactant, the active component loading level is insufficient, resulting in a decrease in catalytic performance. The test results show that at 100°C, the NO removal efficiency is 71.3% after 5 minutes, and the toluene removal efficiency is 56.3%.

[0071] Comparative Example 3

[0072] 1. Preparation of rare earth-based catalysts

[0073] No cerium salt was added during the supercritical hydrothermal reaction, and the other steps were the same as in Example 3.

[0074] 2. Activity Test Results

[0075] Take 0.5mL of 40-60 mesh catalyst, pour it into a quartz tube with an inner diameter of 8mm, fix it with quartz wool and wire mesh, place the quartz tube in a tube furnace, and adjust the actual temperature of the catalytic reaction by controlling the heating temperature of the tube furnace. Use toluene as a representative substance of VOCs, use laboratory gas to simulate flue gas, the intake components are: NO (500ppm), NH3 (500ppm), O2 (11vol.%), toluene (500ppm), and the rest are N2. The total gas flow rate is 500mL / min. Use Laoying 3021 portable carbon emission monitor to test NO concentration, and use Trace 1300ISQ 7000 gas chromatograph-mass spectrometer to test toluene concentration. Figure 2 and Figure 3 As shown, since no cerium salt was added as a precursor of the cerium oxide support, only the active component composite oxide was formed, the pollutant adsorption strength was insufficient and the reaction active sites were few, resulting in a decrease in catalytic performance. The test results showed that at 100°C, the NO removal efficiency was 41.6% after 5 minutes, and the toluene removal efficiency was 26.7%.

Claims

1. A rare earth-based catalyst for simultaneous denitration and VOC removal using ordered wavy micropores, characterized by: The catalyst uses light rare earth europium, lanthanum, and samarium composite oxides as active components, cerium oxide as a carrier, and is based on an amino acid-type amphoteric surfactant. It uses acid solution-guided strengthening and, in the presence of an organic modifier, a one-step supercritical hydrothermal method to synthesize ordered wavy microporous nanocatalysts. The preparation method of the catalyst is as follows: (1) Preparation of active component precursor solution Adding europium salt, lanthanum salt and samarium salt into deionized water and stirring to obtain an active component precursor solution; (2) Supercritical hydrothermal reaction Transferring the cerium salt, surfactant, acid solution, organic modifier and the active component precursor solution prepared in step (1) into a supercritical hydrothermal reactor for supercritical hydrothermal reaction; (3) Final formation of the catalyst The solid-liquid mixture obtained after the reaction in step (2) is filtered to collect the solid product, and then placed in a forced air drying oven to keep warm and dry to obtain the desired catalyst; Wherein, the surfactant is sodium dodecylaminopropionate; the acid solution is a hydrochloric acid solution with a mass fraction of 5-10wt%; and the organic modifier is n-hexanal or n-valeraldehyde.

2. The ordered wavy microporous rare earth-based catalyst for simultaneous denitration and VOCs removal according to claim 1, characterized in that: Based on the mass of the carrier, the mass percentage of the active component is 2-10%; the mass ratio of europium oxide: lanthanum oxide: samarium oxide in the active component is 5: (2-5): (1-2).

3. The ordered wavy microporous rare earth-based catalyst for simultaneous denitration and VOCs removal according to claim 1, characterized in that: The mass ratio of carrier: surfactant: acid solution: organic modifier is: 10: (0.1~0.5): (0.1~0.2): (0.05~0.1).

4. The ordered wavy microporous rare earth-based catalyst for simultaneous denitration and VOCs removal according to claim 1, characterized in that: The europium salt described in step (1) is europium nitrate or europium trichloride; the lanthanum salt is lanthanum nitrate; and the samarium salt is samarium nitrate or samarium chloride.

5. The ordered wavy microporous rare earth-based catalyst for simultaneous denitration and VOCs removal according to claim 1, characterized in that: The mass ratio of the total mass of the europium salt, lanthanum salt and samarium salt described in step (1) to deionized water is 1:60~120.

6. The ordered wavy microporous rare earth-based catalyst for simultaneous denitration and VOCs removal according to claim 1, characterized in that: The cerium salt described in step (2) is cerium nitrate hexahydrate or cerium chloride heptahydrate.

7. The ordered wavy microporous rare earth-based catalyst for simultaneous denitration and VOCs removal according to claim 1, characterized in that: The supercritical hydrothermal reaction temperature in step (2) is 400-500°C, and the reaction time is 15-30 min.

8. The ordered wavy microporous rare earth-based catalyst for simultaneous denitration and VOCs removal according to claim 1, characterized in that: The drying temperature in step (3) is 100-120°C, and the drying time is 2-4 hours.

9. Use of the rare earth-based catalyst according to claim 1 in denitration and VOCs removal.

Images