Oxidation catalyst, method for forming the same, and method for treating flue gas

Abstract

The present invention provides a method for forming an oxidation catalyst, comprising: dissolving a salt of Cu, a salt of M, glycine, and sucrose in water to form a neutral aqueous solution, wherein M is Ce or Mn; and heating the neutral aqueous solution to 350-500°C to produce a large amount of gas, and the oxidation catalyst is obtained after the water is dried, wherein the chemical formula of the oxidation catalyst is Cu 1‑x M x O y wherein x is 0.1-0.9; and y is a value corresponding to the valence of Cu and M, wherein the oxidation catalyst has both mesopores and macropores.

Description

Technical Field

[0001] This invention relates to oxidation catalysts, and particularly to their formation methods and applications. Background Technology

[0002] Currently, it is necessary to further oxidize residual methane, carbon monoxide, or combinations thereof in flue gas to improve energy utilization and reduce pollution. However, existing catalysts (such as those containing precious metals) cannot withstand high temperatures (such as 700°C to 1000°C), and therefore cannot further oxidize methane, carbon monoxide, or combinations thereof in high-temperature flue gas to heat the flue gas.

[0003] In conclusion, there is an urgent need for new catalysts that not only meet the requirements of high-temperature, oxygen-deficient operating environments but also can be rapidly and mass-produced to reduce costs. Summary of the Invention

[0004] An embodiment of the present invention provides an oxidation catalyst with the chemical formula Cu. 1-x M x O y , where M is Ce or Mn; x is 0.1 to 0.9; and y is the numerical value of the valence of Cu and M respectively, wherein the oxidizing catalyst has both mesopores and macropores.

[0005] In some embodiments, the mesopores of the oxidizing catalyst are 10 nm to 50 nm, while the macropores are 100 nm to 400 nm.

[0006] In some embodiments, the oxidation catalyst does not contain Pt, Pd, Rh, Ru, Au, or Ag.

[0007] An embodiment of the present invention provides a method for forming an oxidation catalyst, comprising: dissolving a salt of Cu, a salt of M, glycine, and sucrose in water to form a neutral aqueous solution, wherein M is Ce or Mn; heating the neutral aqueous solution to 350°C to 500°C to generate a large amount of gas, and obtaining the oxidation catalyst after the water is dried, wherein the chemical formula of the oxidation catalyst is Cu. 1-x M x O y x is 0.1 to 0.9; and y is the value of the corresponding valence of Cu and M, wherein the oxidation catalyst has both mesopores and macropores.

[0008] In some embodiments, the ratio of the molar number of Cu salts to the molar number of M salts to the molar number of glycine is 1:0.5 to 1:1.5.

[0009] In some embodiments, the ratio of the molar amounts of Cu salts and M salts to the molar amounts of sucrose is from 1:0.05 to 1:0.3.

[0010] In some embodiments, the mesopores of the oxidizing catalyst are 10 nm to 50 nm, while the macropores are 100 nm to 400 nm.

[0011] In some embodiments, the oxidation catalyst does not contain Pt, Pd, Rh, Ru, Au, or Ag.

[0012] In some embodiments, the above method further includes calcining an oxidation catalyst, and the calcination temperature is between 850°C and 1150°C.

[0013] An embodiment of the present invention provides a method for treating flue gas, comprising: passing flue gas at a temperature of 650°C to 1050°C through an oxidation catalyst to oxidize methane and / or carbon monoxide in the flue gas to generate water and carbon dioxide, wherein the chemical formula of the oxidation catalyst is Cu. 1-x M x O y , where M is Ce or Mn; x is 0.1 to 0.9; and y is the numerical value of the valence of Cu and M respectively, wherein the oxidizing catalyst has both mesopores and macropores.

[0014] In some embodiments, the mesopores of the oxidizing catalyst are 10 nm to 50 nm, while the macropores are 100 nm to 400 nm.

[0015] In some embodiments, the oxidation catalyst does not contain Pt, Pd, Rh, Ru, Au, or Ag.

[0016] In some embodiments, the flue gas includes 50 ppm to 5000 ppm of methane, 50 ppm to 5000 ppm of carbon monoxide, or a combination thereof, and 1% to 5% of oxygen. Attached Figure Description

[0017] Figure 1 This is an example of the XRD patterns of the oxidation catalyst before and after high-temperature calcination in one embodiment of the present invention. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0019] An embodiment of the present invention provides a method for forming an oxidizing catalyst, comprising: dissolving a salt of Cu, a salt of M, glycine, and sucrose in water to form a neutral aqueous solution, wherein M is Ce or Mn. If the aqueous solution is acidic or alkaline (e.g., pH < 6.5 or > 7.5), it may affect the product structure or produce precipitation. In some embodiments, the molar ratio of the salt of Cu to the salt of M to the molar ratio of glycine is 1:0.5 to 1:1.5. If the proportion of glycine is too low, the reaction to form the oxidizing catalyst will be incomplete. If the proportion of glycine is too high, a large amount of gas will be generated, changing the pore size of the oxidizing catalyst, or resulting in residual unreacted glycine forming carbon slag, making the effect of the oxidizing catalyst in converting methane, carbon monoxide, or the above combinations too low. In some embodiments, the molar ratio of the salt of Cu to the salt of M to the molar ratio of sucrose is 1:0.05 to 1:0.3. If the proportion of sucrose is too low, too little gas will be produced, which will change the pore size of the oxidation catalyst. If the proportion is too high, carbon residue will be generated and remain on the catalyst surface, making the oxidation catalyst less effective at converting methane, carbon monoxide, or a combination thereof.

[0020] The neutral aqueous solution is then heated to 350°C to 500°C, generating a large amount of gas. After the water dries, the oxidation catalyst is obtained. If the heating temperature is too low, the reaction will not produce the oxidation catalyst. If the heating temperature is too high, the reaction may be difficult to control, and the desired oxidation catalyst may not be produced. The chemical formula of the oxidation catalyst is Cu. 1-x M x O y Where M is Ce or Mn; x is 0.1 to 0.9; and y is the numerical value of the valence of Cu and M respectively. If the value of x is too low or too high, methane, carbon monoxide, or a combination thereof cannot be effectively oxidized at high temperatures. In some embodiments, the oxidation catalyst may be further calcined at a temperature between 850°C and 1150°C. Calcination can further remove impurities remaining on the oxidation catalyst. In some embodiments, the oxidation catalyst has both mesopores and macropores. In some embodiments, the mesopores of the oxidation catalyst are 10 nm to 50 nm, and the macropores are 100 nm to 400 nm. If the oxidation catalyst has only mesopores and no macropores, the gas mass transfer efficiency is poor, and the oxidation efficiency is low under high space flow rate conditions. If the oxidation catalyst has only macropores and no mesopores, the specific surface area is low, and there are fewer reactive sites. If the pores of the oxidation catalyst are smaller than the mesopores (e.g., about 5 nm), it is less suitable for gas-solid heterogeneous catalytic reactions because the gas residence time is short, and the reactants do not easily enter the small pores. If the pores of the oxidation catalyst are larger than macropores (e.g., larger than 1 mm), the specific surface area will be too low, resulting in fewer reactive sites. The aforementioned oxidation catalysts do not contain noble metals such as Pt, Pd, Rh, Ru, Au, or Ag. If the oxidation catalyst contains noble metals, it cannot treat flue gas at high temperatures.

[0021] An embodiment of the present invention also provides a method for treating flue gas, comprising: passing flue gas at a temperature of 650°C to 1050°C through the aforementioned oxidation catalyst to oxidize methane and / or carbon monoxide in the flue gas to generate water and carbon dioxide. It is understood that the oxidation catalyst of the present invention can withstand high-temperature flue gas without deterioration.

[0022] In some embodiments, the flue gas comprises 50 ppm to 5000 ppm of methane, 50 ppm to 5000 ppm of carbon monoxide, or a combination thereof, and 1% to 5% oxygen. Generally, the oxygen content in the flue gas produced after combustion is low (e.g., 1% to 5%). The oxidizing catalyst of the present invention does not require the addition of additional oxygen to the flue gas to aid oxidation, and is therefore suitable for oxygen-deficient flue gas. However, if the oxygen content in the flue gas is too low, it may not be effective in oxidizing methane and carbon monoxide. If the proportions of methane, carbon monoxide, or the combination thereof in the flue gas are too low, the effect of further oxidizing methane, carbon monoxide, or the combination thereof with the oxidizing catalyst to increase the flue gas temperature is limited. If the proportions of methane, carbon monoxide, or the combination thereof in the flue gas are too high, it indicates that the device for producing the flue gas may be faulty and the combustion efficiency may be insufficient. In some embodiments, the flue gas may contain small amounts of nitrides such as nitric oxide, and the oxidizing catalyst is not affected by nitrides (e.g., poisoning) and does not affect nitrides. In other words, the oxidizing catalyst of the present invention is also suitable for flue gas containing nitrides.

[0023] In summary, the present invention provides a simple way to manufacture an oxidation catalyst that has both mesopores and macropores, which is suitable for converting methane and / or carbon monoxide in flue gas into carbon dioxide and water at high temperatures and increasing the flue gas temperature.

[0024] To make the above-mentioned and other objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described in detail below:

[0025] Example 1-1

[0026] Dissolve 19.8 mmol of Cu(NO3)2·3H2O and 40.2 mmol of Ce(NO3)3·6H2O in 10 mL of water, and add 70 mmol of glycine and 5 mmol of sucrose to the above metal ion aqueous solution, stirring until completely dissolved. Then heat the solution to 400 °C and react for 2 hours to prepare a porous Cu oxide catalyst. 0.33 Ce 0.67 O y .

[0027] A mixture of gases (containing 500 ppm methane, 100 ppm carbon monoxide, 4% oxygen, and the remainder nitrogen, prepared as simulated flue gas) at 700℃ was subjected to a 10,000-hour... -1The gas flow rate (gas space velocity, GHSV) is introduced into the oxidation catalyst. The oxidized mixed gas is collected and passed through a Fourier transform infrared spectrometer to continuously detect the composition of the oxidized mixed gas, from which the conversion rates of methane (91%) and carbon monoxide (86%) can be obtained.

[0028] Examples 1-2

[0029] Dissolve 19.8 mmol of Cu(NO3)2·3H2O and 40.2 mmol of Ce(NO3)3·6H2O in 10 mL of water. Add 70 mmol of glycine and 15 mmol of sucrose to the above metal ion aqueous solution and stir until completely dissolved. Then heat the above solution to 400 °C and react for 2 hours to prepare a porous Cu oxide catalyst. 0.33 Ce 0.67 O y The specific surface area of ​​this oxidation catalyst is 21.3 m². 2 / g, containing mesopores (10nm to 50nm) and macropores (100nm to 400nm), with a pore volume of 0.15cm. 3 / g. The methods for measuring the above specific surface area, pore size, and pore volume can be found in J.Am.Chem.Soc.2018, 140, 984-992.

[0030] A mixture of gases (containing 500 ppm methane, 100 ppm carbon monoxide, 4% oxygen, and the remainder nitrogen, prepared as simulated flue gas) at 700℃ was subjected to a 10,000-hour... -1 The gas flow rate (gas space velocity, GHSV) is introduced into the oxidation catalyst. The oxidized mixed gas is collected and passed through a Fourier transform infrared spectrometer to continuously detect the composition of the oxidized mixed gas, from which the conversion rates of methane (97%) and carbon monoxide (93%) can be obtained.

[0031] Examples 1-3

[0032] Dissolve 19.8 mmol of Cu(NO3)2·3H2O and 40.2 mmol of Ce(NO3)3·3H2O in 10 mL of water. Add 70 mmol of glycine and 30 mmol of sucrose to the above metal ion aqueous solution and stir until completely dissolved. Then heat the above solution to 400 °C and react for 2 hours to prepare a porous Cu oxide catalyst. 0.33 Ce 0.67 O y .

[0033] A mixture of gases (containing 500 ppm methane, 100 ppm carbon monoxide, 4% oxygen, and the remainder nitrogen, prepared as simulated flue gas) at 700℃ was subjected to a 10,000-hour... -1The gas flow rate (gas space velocity, GHSV) is introduced into the oxidation catalyst. The oxidized mixed gas is collected and passed through a Fourier transform infrared spectrometer to continuously detect the composition of the oxidized mixed gas, from which the conversion rates of methane (87%) and carbon monoxide (81%) can be obtained.

[0034] Examples 1-4

[0035] Dissolve 19.8 mmol of Cu(NO3)2·3H2O and 40.2 mmol of Ce(NO3)3·3H2O in 10 mL of water. Add 25 mmol of glycine and 15 mmol of sucrose to the above metal ion aqueous solution and stir until completely dissolved. Then heat the above solution to 400 °C and react for 2 hours to prepare a porous Cu oxide catalyst. 0.33 Ce 0.67 O y .

[0036] A mixture of gases (containing 500 ppm methane, 100 ppm carbon monoxide, 4% oxygen, and the remainder nitrogen, prepared as simulated flue gas) at 700℃ was subjected to a 10,000-hour... -1 The gas flow rate (gas space velocity, GHSV) is introduced into the oxidation catalyst. The oxidized gas mixture is collected and passed through a Fourier transform infrared spectrometer to continuously detect the composition of the oxidized gas mixture, from which the conversion rates of methane (85%) and carbon monoxide (83%) can be obtained.

[0037] Examples 1-5

[0038] Dissolve 19.8 mmol of Cu(NO3)2·3H2O and 40.2 mmol of Ce(NO3)3·6H2O in 10 mL of water. Add 100 mmol of glycine and 15 mmol of sucrose to the above metal ion aqueous solution and stir until completely dissolved. Then heat the above solution to 400 °C and react for 2 hours to prepare a porous Cu oxide catalyst. 0.33 Ce 0.67 O y .

[0039] A mixture of gases (containing 500 ppm methane, 100 ppm carbon monoxide, 4% oxygen, and the remainder nitrogen, prepared as simulated flue gas) at 700℃ was subjected to a 10,000-hour... -1 The gas flow rate (gas space velocity, GHSV) is introduced into the oxidation catalyst. The oxidized mixed gas is collected and passed through a Fourier transform infrared spectrometer to continuously detect the composition of the oxidized mixed gas, from which the conversion rates of methane (91%) and carbon monoxide (82%) can be obtained.

[0040] Examples 1-6

[0041] Dissolve 19.8 mmol of Cu(NO3)2·3H2O and 40.2 mmol of Ce(NO3)3·6H2O in 10 mL of water. Add 150 mmol of glycine and 15 mmol of sucrose to the above metal ion aqueous solution and stir until completely dissolved. Then heat the above solution to 400 °C and react for 2 hours to prepare a porous Cu oxide catalyst. 0.33 Ce 0.67 O y .

[0042] A mixture of gases (containing 500 ppm methane, 100 ppm carbon monoxide, 4% oxygen, and the remainder nitrogen, prepared as simulated flue gas) at 700℃ was subjected to a 10,000-hour... -1 The gas flow rate (gas space velocity, GHSV) is introduced into the oxidation catalyst. The oxidized gas mixture is collected and passed through a Fourier transform infrared spectrometer to continuously detect the composition of the oxidized gas mixture, from which the conversion rates of methane (88%) and carbon monoxide (74%) can be obtained.

[0043] Comparative Example 1-1 (Sucrose-free)

[0044] 19.8 mmol of Cu(NO3)2·3H2O and 40.2 mmol of Ce(NO3)3·6H2O were dissolved in 10 mL of water, and 70 mmol of glycine was added to the above metal ion aqueous solution. The mixture was stirred until completely dissolved. The solution was then heated to 400 °C and reacted for 2 hours to prepare a porous Cu oxide catalyst. 0.33 Ce 0.67 O y .

[0045] A mixture of gases (containing 500 ppm methane, 100 ppm carbon monoxide, 4% oxygen, and the remainder nitrogen, prepared as simulated flue gas) at 700℃ was subjected to a 10,000-hour... -1 The gas flow rate (gas space velocity, GHSV) is introduced into the oxidation catalyst. The oxidized mixed gas is collected and passed through a Fourier transform infrared spectrometer to continuously detect the composition of the oxidized mixed gas, from which the conversion rates of methane (71%) and carbon monoxide (69%) can be obtained.

[0046] Example 2-1

[0047] Dissolve 6 mmol of Cu(NO3)2·3H2O and 54 mmol of Ce(NO3)3·6H2O in 10 mL of water. Add 70 mmol of glycine and 15 mmol of sucrose to the above metal ion aqueous solution and stir until completely dissolved. Then heat the above solution to 400 °C and react for 2 hours to prepare a porous Cu oxide catalyst. 0.1 Ce 0.9 Oy .

[0048] The synthesized oxidation catalyst was further calcined at 1000℃ (4 hours), and a mixed gas at 700℃ (containing 500ppm methane, 100ppm carbon monoxide, 4% oxygen, and the remainder nitrogen, configured as simulated flue gas) was subjected to a 10000h high-temperature calcination process. -1 The gas flow rate (gas space velocity, GHSV) was introduced into the oxidation catalyst after high-temperature calcination (1000℃). The oxidized mixed gas was collected and passed through a Fourier transform infrared spectrometer to continuously detect the composition of the oxidized mixed gas, and the conversion rates of methane (84%) and carbon monoxide (81%) could be obtained.

[0049] A mixture of gases (containing 500 ppm methane, 100 ppm carbon monoxide, 4% oxygen, and the remainder nitrogen, prepared as simulated flue gas) at 900℃ was subjected to a 10,000-hour... -1 The gas flow rate (gas space velocity, GHSV) was introduced into the oxidation catalyst after high-temperature calcination (1000℃). The oxidized mixed gas was collected and passed through a Fourier transform infrared spectrometer to continuously detect the composition of the oxidized mixed gas, and the conversion rates of methane (89%) and carbon monoxide (88%) could be obtained.

[0050] Example 2-2

[0051] The oxidation catalyst Cu synthesized in Examples 1-2 0.33 Ce 0.67 O y The catalyst was further calcined at 1000℃ (4 hours), and the XRD patterns of the oxidizing catalyst before and after the 1000℃ calcination were measured. Figure 1 As shown in the XRD pattern, the signals of the oxidation catalyst before and after high-temperature calcination are similar, indicating that the oxidation catalyst can withstand high-temperature calcination and maintain its original crystalline morphology, exhibiting good thermal stability.

[0052] A mixture of gases (containing 500 ppm methane, 100 ppm carbon monoxide, 4% oxygen, and the remainder nitrogen, prepared as simulated flue gas) at 700℃ was subjected to a 10,000-hour... -1 The gas flow rate (gas space velocity, GHSV) was introduced into the oxidation catalyst after high-temperature calcination (1000℃). The oxidized mixed gas was collected and passed through a Fourier transform infrared spectrometer to continuously detect the composition of the oxidized mixed gas, and the conversion rates of methane (97%) and carbon monoxide (93%) could be obtained.

[0053] A mixture of gases (containing 500 ppm methane, 100 ppm carbon monoxide, 4% oxygen, and the remainder nitrogen, prepared as simulated flue gas) at 900℃ was subjected to a 10,000-hour... -1The gas flow rate (gas space velocity, GHSV) was introduced into the oxidation catalyst after high-temperature calcination (1000℃). The oxidized mixed gas was collected and passed through a Fourier transform infrared spectrometer to continuously detect the composition of the oxidized mixed gas, and the conversion rates of methane (99.5%) and carbon monoxide (97%) could be obtained.

[0054] A mixture of gases (containing 500 ppm methane, 100 ppm carbon monoxide, 100 ppm nitric oxide, 4% oxygen, and the remainder nitrogen) at 850℃ was prepared as simulated flue gas and subjected to a 10,000-hour cycle. -1 The gas flow rate (gas space velocity, GHSV) was introduced into the oxidation catalyst after high-temperature calcination (1000℃). The oxidized mixed gas was collected and passed through a Fourier transform infrared spectrometer to continuously detect the composition of the oxidized mixed gas. The above steps were repeated 50 times to obtain the conversion rates of methane (each time >99%) and carbon monoxide (each time >90%).

[0055] A mixture of gases (containing 500 ppm methane, 100 ppm carbon monoxide, 100 ppm nitric oxide, 4% oxygen, and the remainder nitrogen) at 1000℃ was prepared as simulated flue gas and subjected to a 10,000-hour cycle. -1 The gas flow rate (gas space velocity, GHSV) was introduced into the oxidation catalyst after high-temperature calcination (1000℃). The oxidized mixed gas was collected and passed through a Fourier transform infrared spectrometer to continuously detect the composition of the oxidized mixed gas. The above steps were repeated 50 times to obtain the conversion rates of methane (each time >99%) and carbon monoxide (each time >90%).

[0056] Example 2-3

[0057] Dissolve 30 mmol of Cu(NO3)2·3H2O and 30 mmol of Ce(NO3)3·6H2O in 10 mL of water. Add 70 mmol of glycine and 15 mmol of sucrose to the above metal ion aqueous solution and stir until completely dissolved. Then heat the above solution to 400 °C and react for 2 hours to prepare a porous Cu oxide catalyst. 0.5 Ce 0.5 O y .

[0058] The synthesized oxidation catalyst was further calcined at 1000℃ (4 hours), and a mixed gas at 700℃ (containing 500ppm methane, 100ppm carbon monoxide, 4% oxygen, and the remainder nitrogen, configured as simulated flue gas) was subjected to a 10000h high-temperature calcination process. -1The gas flow rate (gas space velocity, GHSV) was introduced into the oxidation catalyst after high-temperature calcination (1000℃). The oxidized mixed gas was collected and passed through a Fourier transform infrared spectrometer to continuously detect the composition of the oxidized mixed gas, and the conversion rates of methane (77%) and carbon monoxide (76%) could be obtained.

[0059] A mixture of gases (containing 500 ppm methane, 100 ppm carbon monoxide, 4% oxygen, and the remainder nitrogen, prepared as simulated flue gas) at 900℃ was subjected to a 10,000-hour... -1 The gas flow rate (gas space velocity, GHSV) was introduced into the oxidation catalyst after high-temperature calcination (1000℃). The oxidized mixed gas was collected and passed through a Fourier transform infrared spectrometer to continuously detect the composition of the oxidized mixed gas, and the conversion rates of methane (84%) and carbon monoxide (85%) could be obtained.

[0060] Examples 2-4

[0061] Dissolve 54 mmol of Cu(NO3)2·3H2O and 6 mmol of Ce(NO3)3·6H2O in 10 mL of water. Add 70 mmol of glycine and 15 mmol of sucrose to the above metal ion aqueous solution and stir until completely dissolved. Then heat the above solution to 400 °C and react for 2 hours to prepare a porous Cu oxide catalyst. 0.9 Ce 0.1 O y .

[0062] The synthesized oxidation catalyst was further calcined at 1000℃ (4 hours), and a mixed gas at 700℃ (containing 500ppm methane, 100ppm carbon monoxide, 4% oxygen, and the remainder nitrogen, configured as simulated flue gas) was subjected to a 10000h high-temperature calcination process. -1 The gas flow rate (gas space velocity, GHSV) was introduced into the oxidation catalyst after high-temperature calcination (1000℃). The oxidized mixed gas was collected and passed through a Fourier transform infrared spectrometer to continuously detect the composition of the oxidized mixed gas, and the conversion rates of methane (63%) and carbon monoxide (79%) could be obtained.

[0063] A mixture of gases (containing 500 ppm methane, 100 ppm carbon monoxide, 4% oxygen, and the remainder nitrogen, prepared to simulate real flue gas) at 900℃ was subjected to a 10,000-hour... -1 The gas flow rate (gas space velocity, GHSV) was introduced into the oxidation catalyst after high-temperature calcination (1000℃). The oxidized mixed gas was collected and passed through a Fourier transform infrared spectrometer to continuously detect the composition of the oxidized mixed gas, and the conversion rates of methane (87%) and carbon monoxide (89%) could be obtained.

[0064] Comparative Example 2-1 (Cu is too low)

[0065] Dissolve 3 mmol of Cu(NO3)2·3H2O and 57 mmol of Ce(NO3)3·6H2O in 10 mL of water. Add 70 mmol of glycine and 15 mmol of sucrose to the above metal ion aqueous solution and stir until completely dissolved. Then heat the above solution to 400 °C and react for 2 hours to prepare a porous Cu oxide catalyst. 0.05 Ce 0.95 O y .

[0066] The synthesized oxidation catalyst was further calcined at 1000℃ (4 hours), and a mixed gas at 700℃ (containing 500ppm methane, 100ppm carbon monoxide, 4% oxygen, and the remainder nitrogen, configured as simulated flue gas) was subjected to a 10000h high-temperature calcination process. -1 The gas flow rate (gas space velocity, GHSV) was introduced into the oxidation catalyst after high-temperature calcination (1000℃). The oxidized mixed gas was collected and passed through a Fourier transform infrared spectrometer to continuously detect the composition of the oxidized mixed gas, and the conversion rates of methane (71%) and carbon monoxide (35%) could be obtained.

[0067] Comparative Example 2-2 (Excessive Cu)

[0068] Dissolve 57 mmol of Cu(NO3)2·3H2O and 3 mmol of Ce(NO3)3·6H2O in 10 mL of water. Add 70 mmol of glycine and 15 mmol of sucrose to the above metal ion aqueous solution and stir until completely dissolved. Then heat the above solution to 400 °C and react for 2 hours to prepare a porous Cu oxide catalyst. 0.95 Ce 0.05 O y .

[0069] The synthesized oxidation catalyst was further calcined at 1000℃ (4 hours), and a mixed gas at 700℃ (containing 500ppm methane, 100ppm carbon monoxide, 4% oxygen, and the remainder nitrogen, configured as simulated flue gas) was subjected to a 10000h high-temperature calcination process. -1 The gas flow rate (gas space velocity, GHSV) was introduced into the oxidation catalyst after high-temperature calcination (1000℃). The oxidized mixed gas was collected and passed through a Fourier transform infrared spectrometer to continuously detect the composition of the oxidized mixed gas, and the conversion rates of methane (65%) and carbon monoxide (69%) could be obtained.

[0070] Example 3-1

[0071] Dissolve 6 mmol of Cu(NO3)2·3H2O and 54 mmol of Mn(NO3)2·4H2O in 10 mL of water. Add 70 mmol of glycine and 15 mmol of sucrose to the above metal ion aqueous solution and stir until completely dissolved. Then heat the above solution to 400 °C and react for 2 hours to prepare a porous Cu oxide catalyst. 0.1 Mn 0.9 O y .

[0072] The synthesized oxidation catalyst was further calcined at 1000℃ (4 hours), and a mixed gas at 700℃ (containing 500ppm methane, 100ppm carbon monoxide, 4% oxygen, and the remainder nitrogen, configured as simulated flue gas) was subjected to a 10000h high-temperature calcination process. -1 The gas flow rate (gas space velocity, GHSV) was introduced into the oxidation catalyst after high-temperature calcination (1000℃). The oxidized mixed gas was collected and passed through a Fourier transform infrared spectrometer to continuously detect the composition of the oxidized mixed gas, and the conversion rates of methane (71%) and carbon monoxide (35%) were obtained.

[0073] A mixture of gases (containing 500 ppm methane, 100 ppm carbon monoxide, 4% oxygen, and the remainder nitrogen, prepared as simulated flue gas) at 900℃ was subjected to a 10,000-hour... -1 The gas flow rate (gas space velocity, GHSV) was introduced into the oxidation catalyst after high-temperature calcination (1000℃). The oxidized mixed gas was collected and passed through a Fourier transform infrared spectrometer to continuously detect the composition of the oxidized mixed gas, and the conversion rates of methane (79%) and carbon monoxide (47%) were obtained.

[0074] Example 3-2

[0075] Dissolve 19.8 mmol of Cu(NO3)2·3H2O and 40.2 mmol of Mn(NO3)2·4H2O in 10 mL of water. Add 70 mmol of glycine and 15 mmol of sucrose to the above metal ion aqueous solution and stir until completely dissolved. Then heat the above solution to 400 °C and react for 2 hours to prepare a porous Cu oxide catalyst. 0.33 Mn 0.67 O y .

[0076] The synthesized oxidation catalyst was further calcined at 1000℃ (4 hours), and a mixed gas at 700℃ (containing 500ppm methane, 100ppm carbon monoxide, 4% oxygen, and the remainder nitrogen, configured as simulated flue gas) was subjected to a 10000h high-temperature calcination process. -1The gas flow rate (gas space velocity, GHSV) was introduced into the oxidation catalyst after high-temperature calcination (1000℃). The oxidized mixed gas was collected and passed through a Fourier transform infrared spectrometer to continuously detect the composition of the oxidized mixed gas, and the conversion rates of methane (93%) and carbon monoxide (38%) could be obtained.

[0077] A mixture of gases (containing 500 ppm methane, 100 ppm carbon monoxide, 4% oxygen, and the remainder nitrogen, prepared as simulated flue gas) at 900℃ was subjected to a 10,000-hour... -1 The gas flow rate (gas space velocity, GHSV) was introduced into the oxidation catalyst after high-temperature calcination (1000℃). The oxidized mixed gas was collected and passed through a Fourier transform infrared spectrometer to continuously detect the composition of the oxidized mixed gas, and the conversion rates of methane (95%) and carbon monoxide (55%) could be obtained.

[0078] Example 3-3

[0079] Dissolve 30 mmol of Cu(NO3)2·3H2O and 30 mmol of Mn(NO3)2·4H2O in 10 mL of water. Add 70 mmol of glycine and 15 mmol of sucrose to the above metal ion aqueous solution and stir until completely dissolved. Then heat the above solution to 400 °C and react for 2 hours to prepare a porous Cu oxide catalyst. 0.5 Mn 0.5 O y .

[0080] The synthesized oxidation catalyst was further calcined at 1000℃ (4 hours), and a mixed gas at 700℃ (containing 500ppm methane, 100ppm carbon monoxide, 4% oxygen, and the remainder nitrogen, configured as simulated flue gas) was subjected to a 10000h high-temperature calcination process. -1 The gas flow rate (gas space velocity, GHSV) was introduced into the oxidation catalyst after high-temperature calcination (1000℃). The oxidized mixed gas was collected and passed through a Fourier transform infrared spectrometer to continuously detect the composition of the oxidized mixed gas, and the conversion rates of methane (85%) and carbon monoxide (47%) could be obtained.

[0081] A mixture of gases (containing 500 ppm methane, 100 ppm carbon monoxide, 4% oxygen, and the remainder nitrogen, prepared as simulated flue gas) at 900℃ was subjected to a 10,000-hour... -1 The gas flow rate (gas space velocity, GHSV) was introduced into the oxidation catalyst after high-temperature calcination (1000℃). The oxidized mixed gas was collected and passed through a Fourier transform infrared spectrometer to continuously detect the composition of the oxidized mixed gas, and the conversion rates of methane (88%) and carbon monoxide (51%) were obtained.

[0082] Examples 3-4

[0083] Dissolve 54 mmol of Cu(NO3)2·3H2O and 6 mmol of Mn(NO3)2·4H2O in 10 mL of water. Add 70 mmol of glycine and 15 mmol of sucrose to the above metal ion aqueous solution and stir until completely dissolved. Then heat the above solution to 400 °C and react for 2 hours to prepare a porous Cu oxide catalyst. 0.9 Mn 0.1 O y .

[0084] The synthesized oxidation catalyst was further calcined at 1000℃ (4 hours), and a mixed gas at 700℃ (containing 500ppm methane, 100ppm carbon monoxide, 4% oxygen, and the remainder nitrogen, configured as simulated flue gas) was subjected to a 10000h high-temperature calcination process. -1 The gas flow rate (gas space velocity, GHSV) was introduced into the oxidation catalyst after high-temperature calcination (1000℃). The oxidized mixed gas was collected and passed through a Fourier transform infrared spectrometer to continuously detect the composition of the oxidized mixed gas, and the conversion rates of methane (81%) and carbon monoxide (55%) could be obtained.

[0085] A mixture of gases (containing 500 ppm methane, 100 ppm carbon monoxide, 4% oxygen, and the remainder nitrogen, prepared as simulated flue gas) at 900℃ was subjected to a 10,000-hour... -1 The gas flow rate (gas space velocity, GHSV) was introduced into the oxidation catalyst after high-temperature calcination (1000℃). The oxidized mixed gas was collected and passed through a Fourier transform infrared spectrometer to continuously detect the composition of the oxidized mixed gas, and the conversion rates of methane (88%) and carbon monoxide (65%) could be obtained.

[0086] Comparative Example 3-1 (Cu too low)

[0087] Dissolve 3 mmol of Cu(NO3)2·3H2O and 57 mmol of Mn(NO3)2·4H2O in 10 mL of water. Add 70 mmol of glycine and 15 mmol of sucrose to the above metal ion aqueous solution and stir until completely dissolved. Then heat the above solution to 400 °C and react for 2 hours to prepare a porous Cu oxide catalyst. 0.05 Mn 0.95 O y .

[0088] The synthesized oxidation catalyst was further calcined at 1000℃ (4 hours), and a mixed gas at 700℃ (containing 500ppm methane, 100ppm carbon monoxide, 4% oxygen, and the remainder nitrogen, configured as simulated flue gas) was subjected to a 10000h high-temperature calcination process. -1The gas flow rate (gas space velocity, GHSV) was introduced into the oxidation catalyst after high-temperature calcination (1000°C). The oxidized mixed gas was collected and passed through a Fourier transform infrared spectrometer to continuously detect the composition of the oxidized mixed gas, and the conversion rates of methane (72%) and carbon monoxide (29%) were obtained.

[0089] Comparative Example 3-2 (Excessive Cu)

[0090] Dissolve 57 mmol of Cu(NO3)2·3H2O and 3 mmol of Mn(NO3)2·4H2O in 10 mL of water. Add 70 mmol of glycine and 15 mmol of sucrose to the above metal ion aqueous solution and stir until completely dissolved. Then heat the above solution to 400 °C and react for 2 hours to prepare a porous Cu oxide catalyst. 0.95 Mn 0.05 O y .

[0091] The synthesized oxidation catalyst was further calcined at 1000℃ (4 hours), and a mixed gas at 700℃ (containing 500ppm methane, 100ppm carbon monoxide, 4% oxygen, and the remainder nitrogen, configured as simulated flue gas) was subjected to a 10000h high-temperature calcination process. -1 The gas flow rate (gas space velocity, GHSV) was introduced into the oxidation catalyst after high-temperature calcination (1000℃). The oxidized mixed gas was collected and passed through a Fourier transform infrared spectrometer to continuously detect the composition of the oxidized mixed gas, and the conversion rates of methane (61%) and carbon monoxide (45%) could be obtained.

[0092] Comparative Example 4 (Combustion solution temperature too low)

[0093] Dissolve 19.8 mmol of Cu(NO3)2·3H2O and 40.2 mmol of Ce(NO3)3·6H2O in 10 mL of water. Add 70 mmol of glycine and 15 mmol of sucrose to the above metal ion aqueous solution and stir until completely dissolved. Then heat the above solution to 200 °C and react for 3 hours to prepare a porous Cu oxide catalyst. 0.33 Ce 0.67 O y .

[0094] A mixture of gases (containing 500 ppm methane, 100 ppm carbon monoxide, 4% oxygen, and the remainder nitrogen, prepared as simulated flue gas) at 700℃ was subjected to a 10,000-hour... -1 The gas flow rate (gas space velocity, GHSV) is introduced into the oxidation catalyst. The oxidized mixed gas is collected and passed through a Fourier transform infrared spectrometer to continuously detect the composition of the oxidized mixed gas, from which the conversion rates of methane (59%) and carbon monoxide (39%) can be obtained.

[0095] Comparative Example 5

[0096] Example 4 of Chinese Patent CN110124710B was repeated to obtain a porous oxidation catalyst CeCuO3-Cu3O4-Ce2O2CO3 with pores of approximately 5 nm. A mixed gas (containing 500 ppm methane, 100 ppm carbon monoxide, 4% oxygen, and the remainder nitrogen, configured as simulated flue gas) was prepared at 700°C for 10,000 h⁻¹. -1 The gas flow rate (gas space velocity, GHSV) was introduced into the oxidation catalyst. The oxidized mixture was collected and passed through a Fourier transform infrared spectrometer to continuously detect the composition of the oxidized mixture, which yielded the conversion rates of methane (69%) and carbon monoxide (31%).

[0097] Comparative Example 6 (Coprecipitation)

[0098] 19.8 mmol of Cu(NO3)2·3H2O and 40.2 mmol of Ce(NO3)3·6H2O were dissolved in 10 mL of water, and sodium hydroxide solution was added to the above metal ion aqueous solution to precipitate a solid. After filtration, the filter cake was dried and calcined at 500 °C for 2 hours to obtain the oxidizing catalyst Cu. 0.33 Ce 0.67 O y .

[0099] A mixture of gases (containing 500 ppm methane, 100 ppm carbon monoxide, 4% oxygen, and the remainder nitrogen, prepared as simulated flue gas) at 700℃ was subjected to a 10,000-hour... -1 The gas flow rate (gas space velocity, GHSV) is introduced into the oxidation catalyst. The oxidized gas mixture is collected and passed through a Fourier transform infrared spectrometer to continuously detect the composition of the oxidized gas mixture, from which the conversion rates of methane (85%) and carbon monoxide (65%) can be obtained.

[0100] Comparative Example 7 (Mixed)

[0101] Dissolve 60 mmol of Cu(NO3)2·3H2O in 10 mL of water, and add sodium hydroxide solution to the above copper ion aqueous solution to precipitate a solid. Filter the solution, dry the filter cake, and calcine it at 500 °C for 2 hours to obtain CuO. Dissolve 60 mmol of Ce(NO3)3·6H2O in 10 mL of water, and add sodium hydroxide solution to the above cerium ion aqueous solution to precipitate a solid. Filter the solution, dry the filter cake, and calcine it at 500 °C for 2 hours to obtain CeO2. Mix 1 mole of CuO with 2 moles of CeO2 to prepare an oxidation catalyst.

[0102] A mixture of gases (containing 500 ppm methane, 100 ppm carbon monoxide, 4% oxygen, and the remainder nitrogen, prepared as simulated flue gas) at 700℃ was subjected to a 10,000-hour... -1 The gas flow rate (gas space velocity, GHSV) is introduced into the oxidation catalyst. The oxidized mixed gas is collected and passed through a Fourier transform infrared spectrometer to continuously detect the composition of the oxidized mixed gas, from which the conversion rates of methane (81%) and carbon monoxide (30%) can be obtained.

[0103] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An oxidation catalyst, characterized in that, Its chemical formula is Cu 1-x M x O y , Where M is either Ce or Mn; x ranges from 0.1 to 0.9; and y represents the valence values ​​of Cu and M, respectively. The oxidation catalyst has both mesopores and macropores, with the mesopores being 10 nm to 50 nm and the macropores being 100 nm to 400 nm; and the oxidation catalyst does not contain Pt, Pd, Rh, Ru, Au, or Ag.

2. A method for forming an oxidation catalyst, characterized in that, include: Salts of Cu, salts of M, glycine, and sucrose are dissolved in water to form a neutral aqueous solution, wherein M is Ce or Mn; and, Heating the neutral aqueous solution to 350°C to 500°C produces a large amount of gas. After the water is dried, the oxidation catalyst is obtained. The chemical formula of the oxidation catalyst is Cu. 1-x M x O y , Where x ranges from 0.1 to 0.9; and y represents the valence values ​​of Cu and M, respectively. The oxidation catalyst has both mesopores and macropores; the mesopores of the oxidation catalyst are 10 nm to 50 nm, and the macropores are 100 nm to 400 nm; the oxidation catalyst does not contain Pt, Pd, Rh, Ru, Au, or Ag; the molar ratio of the salts of Cu to the salts of M to the molar ratio of glycine is 1:0.5 to 1:1.

5. The ratio of the molar number of Cu salts to the molar number of M salts to the molar number of sucrose is 1:0.05 to 1:0.

3.

3. The method for forming an oxidation catalyst according to claim 2, characterized in that, It also includes calcining the oxidation catalyst at a temperature between 850°C and 1150°C.

4. A method for treating flue gas, characterized in that, include: Flue gas at a temperature of 650°C to 1050°C is passed through an oxidation catalyst to oxidize methane and / or carbon monoxide in the flue gas, producing water and carbon dioxide. The chemical formula of the oxidation catalyst is Cu. 1-x M x O y , Where M is either Ce or Mn; x ranges from 0.1 to 0.9; and y represents the valence values ​​of Cu and M, respectively. The oxidation catalyst has both mesopores and macropores. The mesopores of the oxidation catalyst are 10 nm to 50 nm, and the macropores are 100 nm to 400 nm; and the oxidation catalyst does not contain Pt, Pd, Rh, Ru, Au, or Ag.

5. The method for treating flue gas according to claim 4, characterized in that, The flue gas includes 50 ppm to 5000 ppm of methane and / or 50 ppm to 5000 ppm of carbon monoxide, and 1% to 5% of oxygen.

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