Catalyst for the catalytic oxidation of co and method for its preparation and use

Abstract

The application discloses a catalyst for catalytic oxidation of CO, a preparation method and application thereof. The catalyst is prepared from raw materials including the following components: 60-95 parts by weight of titanium dioxide, 1-20 parts by weight of aluminum oxide, 5-25 parts by weight of manganese oxide, 1-15 parts by weight of silicon carbide, 0.5-8 parts by weight of activated carbon, 0.1-5 parts by weight of magnesium sulfate, 6.5-9 parts by weight of cerium oxide precursor, 0.7-1.4 parts by weight of tungsten oxide precursor, 0.7-1.7 parts by weight of molybdenum oxide precursor, 3.5-4.5 parts by weight of copper oxide precursor and 1.2-1.7 parts by weight of lanthanum oxide precursor. The catalyst has high catalytic efficiency for CO.

Description

Technical Field

[0001] This invention relates to a catalyst for the catalytic oxidation of CO, its preparation method, and its uses. Background Technology

[0002] CO is a major toxic gaseous pollutant, and its elimination has received widespread attention from researchers. Many industries emit large amounts of CO in their flue gas, causing serious environmental impacts. Catalytic oxidation of CO can reduce emissions and reuse exothermic energy, achieving energy conservation and emission reduction.

[0003] CN110013853A discloses a catalyst for the gas-phase hydrodechlorination preparation of 2,3,3,3-tetrafluoropropylene. This catalyst consists of an active component and a support. The active component is one or more of the metals Ni, Mo, W, Co, Cr, Cu, Ce, La, Mn, and Fe. The support is one of oxides, fluorides, activated carbon, and molecular sieves. The active component accounts for 0.01–50% of the total mass of the catalyst. CN116159556A discloses a supported ozone catalyst prepared from the following raw materials: a catalyst support, a binder, and an active component. The active component consists of a main catalyst and a co-catalyst. The main catalyst is a combination of oxides of any one or more elements selected from manganese, iron, cobalt, titanium, nickel, magnesium, zinc, copper, vanadium, lithium, barium, tungsten, silicon, and calcium. The co-catalyst is a combination of oxides of any one or more metal elements selected from scandium, chromium, molybdenum, cerium, tin, zirconium, ruthenium, rhodium, palladium, lanthanum, cerium, and platinum. The catalysts mentioned above are not suitable for the catalytic oxidation of CO.

[0004] CN113828311A discloses a method for preparing a highly sulfur-resistant catalyst for CO removal. The method involves uniformly mixing coal powder, a binder, and a pore-forming agent to obtain mixture A; adding mixture B to mixture A and mixing thoroughly to obtain mixture C. Mixture B is a mixture of a binder and an antisulfur agent. Mixture C is stirred uniformly with water and pressed into a sample; the sample is then subjected to pyrolysis and activation sequentially under an inert atmosphere, yielding a carbonaceous material containing the antisulfur agent. The carbonaceous material containing the antisulfur agent is impregnated in an impregnation solution containing a catalytically active component and ammonium nitrate, followed by drying and calcination under an inert atmosphere to obtain the highly sulfur-resistant catalyst for CO removal. The stability of this catalyst needs further improvement. Summary of the Invention

[0005] In view of this, one object of the present invention is to provide a catalyst for the catalytic oxidation of CO, which exhibits excellent sulfur resistance and water resistance, and high catalytic efficiency for CO. Furthermore, the catalyst has a long stability time. Another object of the present invention is to provide a method for preparing the catalyst, which improves the catalytic efficiency and stability time of the catalyst. A further object of the present invention is to provide an application of the catalyst.

[0006] The above objectives are achieved through the following technical solutions.

[0007] On one hand, the present invention provides a catalyst for the catalytic oxidation of CO, said catalyst being prepared from raw materials comprising the following composition:

[0008] 60-95 parts by weight of titanium dioxide, 1-20 parts by weight of aluminum oxide, 5-25 parts by weight of manganese oxide, 1-15 parts by weight of silicon carbide, 0.5-8 parts by weight of activated carbon, and 0.1-5 parts by weight of magnesium sulfate;

[0009] The precursors are: 6.5 to 9 parts by weight of cerium oxide, 0.7 to 1.4 parts by weight of tungsten oxide, 0.7 to 1.7 parts by weight of molybdenum oxide, 3.5 to 4.5 parts by weight of copper oxide, and 1.2 to 1.7 parts by weight of lanthanum oxide.

[0010] The amount of cerium oxide precursor used is calculated as cerium oxide, the amount of tungsten oxide precursor used is calculated as tungsten trioxide, the mass of molybdenum oxide precursor is calculated as molybdenum oxide, the mass of copper oxide precursor is calculated as copper oxide, and the mass of lanthanum oxide precursor is calculated as lanthanum oxide.

[0011] According to the catalyst of the present invention, preferably, the raw materials further include 1 to 10 parts by weight of a pore-forming agent, 0.5 to 5 parts by weight of a binder, 0.5 to 7 parts by weight of an internal lubricant, 1 to 10 parts by weight of an external lubricant, and 5 to 25 parts by weight of a structural reinforcing agent.

[0012] According to the catalyst of the present invention, preferably, the pore-forming agent is wood shell powder, the binder is hydroxypropyl methylcellulose, the internal lubricant is starch, the external lubricant is a mixture of glycerol and ethanolamine, and the structural reinforcing agent is glass fiber.

[0013] According to the catalyst of the present invention, preferably, the cerium oxide precursor is a water-soluble cerium salt, the tungsten oxide precursor is a water-soluble tungstate, the molybdenum oxide precursor is molybdenum oxide, the copper oxide precursor is copper oxide, and the lanthanum oxide precursor is a water-soluble lanthanum salt.

[0014] The catalyst according to the present invention is preferably a honeycomb catalyst.

[0015] On the other hand, the present invention provides a method for preparing the above-mentioned catalyst, comprising the following steps:

[0016] (1) Forming catalyst sludge from raw materials;

[0017] (2) The catalyst sludge is aged to obtain aged sludge; the aged sludge is mixed to obtain mixed sludge; the mixed sludge is extruded to obtain a honeycomb-shaped catalyst blank;

[0018] (3) Dry the honeycomb-shaped catalyst preform to obtain a dried preform;

[0019] (4) The dried green body is calcined to obtain the catalyst.

[0020] According to the preparation method of the present invention, preferably, the aging is carried out at a temperature of 25-45°C and a humidity of 40-70% for a time of 18-35 hours;

[0021] The roasting temperature is 400–650℃, and the roasting time is 5–12 hours.

[0022] According to the preparation method of the present invention, preferably, the catalyst preform is dried once at a temperature of 25-45°C and a humidity of 40-75%, dried a second time at a temperature of 35-70°C and a humidity of 60-90%, and dried a third time at a temperature of 100-140°C and a humidity of 80-95%.

[0023] According to the preparation method of the present invention, preferably, step (1) includes the following steps:

[0024] (a) Titanium dioxide, aluminum oxide, manganese oxide, silicon carbide, activated carbon, magnesium sulfate, pore-forming agent and internal lubricant are mixed to obtain a first mixture;

[0025] (b) The first mixture, the molybdenum oxide precursor, and the copper oxide precursor are mixed to obtain a second mixture;

[0026] (c) The second mixture is mixed with an active salt solution comprising cerium oxide precursor, tungsten oxide precursor, lanthanum oxide precursor and water to obtain a third mixture;

[0027] (d) The third mixture and the structural reinforcing agent are mixed to obtain the fourth mixture;

[0028] (e) The fourth mixture is mixed with the binder and then with the external lubricant to obtain the catalyst slurry.

[0029] In another aspect, the present invention provides the use of the above-mentioned catalyst in the catalytic oxidation of CO.

[0030] The catalyst of this invention exhibits excellent sulfur and water resistance, high catalytic efficiency for CO, and long stability. Furthermore, the catalyst does not contain precious metals such as ruthenium, rhodium, palladium, osmium, iridium, platinum, gold, and silver, resulting in lower cost. Detailed Implementation

[0031] The present invention will be further described below with reference to specific embodiments, but the scope of protection of the present invention is not limited thereto.

[0032] Catalysts for CO catalytic oxidation

[0033] The catalyst for the catalytic oxidation of CO of the present invention is prepared from raw materials comprising the following components: titanium dioxide, alumina, manganese oxide, silicon carbide, activated carbon, magnesium sulfate, cerium oxide precursor, tungsten oxide precursor, molybdenum oxide precursor, copper oxide precursor, and lanthanum oxide precursor. In some embodiments, the raw materials further include a pore-forming agent, a binder, an internal lubricant, an external lubricant, a structure-enhancing agent, and water. The catalyst of the present invention does not contain precious metals such as ruthenium, rhodium, palladium, osmium, iridium, platinum, gold, and silver. In some embodiments, the catalyst of the present invention is composed of the above-mentioned raw materials. The catalyst of the present invention is a honeycomb catalyst.

[0034] The amount of titanium dioxide used is 60 to 95 parts by weight; preferably 65 to 90 parts by weight; more preferably 70 to 80 parts by weight.

[0035] The amount of alumina used is 1 to 20 parts by weight; preferably 3 to 18 parts by weight; more preferably 5 to 12 parts by weight.

[0036] The amount of manganese oxide used is 5 to 25 parts by weight; preferably 10 to 20 parts by weight; more preferably 10 to 12 parts by weight.

[0037] The amount of silicon carbide used is 1 to 15 parts by weight; preferably 3 to 10 parts by weight; more preferably 5 to 7 parts by weight. Silicon carbide is used in powder form.

[0038] The amount of activated carbon used is 0.5 to 8 parts by weight; preferably 0.5 to 5 parts by weight; more preferably 1 to 3 parts by weight. The activated carbon is used in powder form.

[0039] The amount of magnesium sulfate used is 0.1 to 5 parts by weight; preferably 0.5 to 3 parts by weight; more preferably 1 to 2 parts by weight.

[0040] The amount of cerium oxide precursor used is 6.5 to 9 parts by weight; preferably 7 to 8.5 parts by weight; more preferably 7.5 to 8 parts by weight. The amount of cerium oxide precursor used is based on cerium oxide.

[0041] The amount of tungsten oxide precursor used is 0.7 to 1.4 parts by weight; preferably 0.8 to 1.2 parts by weight; more preferably 1 to 1.12 parts by weight. The amount of tungsten oxide precursor used is based on tungsten trioxide.

[0042] The amount of molybdenum oxide precursor used is 0.7 to 1.7 parts by weight; preferably 0.9 to 1.5 parts by weight; more preferably 1.13 to 1.3 parts by weight. The amount of molybdenum oxide precursor used is calculated as molybdenum oxide.

[0043] The amount of copper oxide precursor used is 3.5 to 4.5 parts by weight; preferably 3.6 to 4.2 parts by weight; more preferably 3.75 to 4 parts by weight.

[0044] The amount of lanthanum oxide precursor used is 1.2 to 1.7 parts by weight; preferably 1.3 to 1.6 parts by weight; more preferably 1.4 to 1.5 parts by weight.

[0045] Controlling the above raw materials within the above range is beneficial to improving the catalyst's resistance to water and sulfur, as well as its catalytic efficiency and stabilization time for CO.

[0046] The cerium oxide precursor can be a water-soluble cerium salt. The water-soluble cerium salt is preferably cerium acetate. The tungsten oxide precursor can be a water-soluble tungstate. The water-soluble tungstate is preferably ammonium metatungstate. The lanthanum oxide precursor can be a water-soluble lanthanum salt. The water-soluble lanthanum salt is preferably lanthanum nitrate. This helps to uniformly distribute the above elements in the catalyst, improving the catalytic efficiency and stabilization time of the catalyst.

[0047] The molybdenum oxide precursor can be molybdenum oxide. The copper oxide precursor can be copper oxide. This can improve the catalyst strength and increase the stabilization time.

[0048] The amount of pore-forming agent can be 1 to 10 parts by weight; preferably 3 to 8 parts by weight; more preferably 5 to 6 parts by weight. The pore-forming agent can be selected from one or more of polymethyl methacrylate, chitosan, hydroxypropyl methylcellulose, ammonium carbonate, starch, polyethylene oxide, urea, and wood husk powder. Preferably, the pore-forming agent is wood husk powder. This can improve the catalytic efficiency of the catalyst and ensure that the catalyst has appropriate strength.

[0049] The amount of binder can be 0.5 to 5 parts by weight; preferably 1 to 4 parts by weight; more preferably 2 to 3 parts by weight. Hydroxypropyl methylcellulose is preferred as the binder. This improves the catalytic efficiency of the catalyst and ensures that the catalyst has appropriate strength.

[0050] The amount of internal lubricant can be 0.5 to 7 parts by weight; preferably 1 to 5 parts by weight; more preferably 3 to 4 parts by weight. The internal lubricant is preferably starch.

[0051] The amount of external lubricant can be 1 to 10 parts by weight; preferably 3 to 7 parts by weight; more preferably 5 to 6 parts by weight. The external lubricant is preferably a mixture of glycerol and ethanolamine. The mass ratio of glycerol to ethanolamine can be 1:(0.5 to 1.5); preferably 1:(0.8 to 1.2).

[0052] The amount of structural reinforcing agent can be 5 to 25 parts by weight; preferably 7 to 20 parts by weight; more preferably 10 to 15 parts by weight. The structural reinforcing agent is preferably glass fiber.

[0053] The amount of water used can be 10 to 60 parts by weight; preferably 10 to 40 parts by weight; more preferably 15 to 25 parts by weight.

[0054] <Catalyst Preparation Methods>

[0055] The method for preparing the catalyst of the present invention includes the following steps: (1) forming catalyst slurry; (2) aging and shaping; (3) drying; and (4) calcination.

[0056] Steps for forming catalyst sludge

[0057] This invention forms catalyst sludge from raw materials.

[0058] In some implementations, the following steps are included:

[0059] (a) Titanium dioxide, aluminum oxide, manganese oxide, silicon carbide, activated carbon, magnesium sulfate, pore-forming agent and internal lubricant are mixed to obtain a first mixture;

[0060] (b) The first mixture, the molybdenum oxide precursor, and the copper oxide precursor are mixed to obtain a second mixture;

[0061] (c) The second mixture is mixed with an active salt solution comprising cerium oxide precursor, tungsten oxide precursor, lanthanum oxide precursor and water to obtain a third mixture;

[0062] (d) The third mixture and the structural reinforcing agent are mixed to obtain the fourth mixture;

[0063] (e) The fourth mixture is mixed with the binder and then with the external lubricant to obtain the catalyst slurry.

[0064] In step (a), the mixing temperature can be 15–35°C; preferably 20–30°C. The mixing time can be 10–45 min; preferably 20–35 min. Mixing is carried out at a rotation speed of 200–800 rpm; preferably 300–600 rpm.

[0065] In step (b), the mixing temperature can be 15–35°C; preferably 20–30°C. The mixing time can be 20–90 min; preferably 30–60 min. Mixing is carried out at a rotation speed of 200–800 rpm; preferably 300–600 rpm.

[0066] In step (c), the second mixture is mixed with the active salt solution at a temperature of 15–35°C, preferably 20–30°C, for 10–45 min, preferably 20–35 min; then, it is mixed at a temperature of 40–80°C, preferably 50–70°C, for 5–30 min, preferably 10–20 min. The above steps are performed at a rotation speed of 100–500 rpm, preferably 200–400 rpm.

[0067] The active salt solution can be added to the second mixture in multiple portions, for example, 2 to 5 times, or 3 to 4 times.

[0068] In step (d), the mixing temperature can be 40–80°C; preferably 50–70°C. The mixing time can be 30–90 min; preferably 50–70 min. Mixing is carried out at a rotation speed of 100–500 rpm; preferably 200–400 rpm.

[0069] The structural reinforcing agent can be added to the third mixture in multiple stages. For example, 2 to 5 times, or 3 to 4 times.

[0070] In step (e), the fourth mixture is mixed with the binder at a temperature of 40–80°C, preferably 50–70°C and a rotation speed of 100–500 rpm, preferably 200–400 rpm, for 10–45 min, preferably 20–35 min; then mixed with the external lubricant at a temperature of 40–80°C, preferably 50–70°C and a rotation speed of 100–500 rpm, preferably 200–400 rpm, for 10–45 min, preferably 20–35 min, to obtain the catalyst slurry.

[0071] The above mixing method helps to improve the uniformity of the catalyst slurry, thereby increasing the catalytic efficiency and stabilization time of the resulting catalyst.

[0072] Aging and shaping steps

[0073] The present invention involves aging catalyst sludge to obtain aged sludge; mixing the aged sludge to obtain mixed sludge; and extruding the mixed sludge to obtain a honeycomb-shaped catalyst blank.

[0074] The aging temperature can be 20–45°C; preferably 25–40°C; more preferably 30–35°C.

[0075] The aging humidity can be 40-80%; preferably 50-70%; more preferably 60-65%.

[0076] The aging time can be 12 to 36 hours; preferably 15 to 30 hours; more preferably 20 to 25 hours.

[0077] Mixing can be carried out in a vacuum ply mill. Mixing can be performed multiple times, for example, 2 to 5 times, or 3 to 4 times. This allows air to be expelled from the ply material.

[0078] Drying steps

[0079] This invention involves drying a honeycomb-shaped catalyst preform to obtain a dried preform. In some embodiments, the honeycomb-shaped catalyst preform is subjected to primary drying, secondary drying, and tertiary drying, respectively.

[0080] The primary drying temperature can be 25–45°C; preferably 30–40°C; more preferably 35–38°C.

[0081] The primary drying humidity can be 40-75%; preferably 50-70%; more preferably 60-65%.

[0082] The drying time can be 10 to 36 hours; preferably 12 to 24 hours; more preferably 15 to 20 hours.

[0083] The secondary drying temperature can be 35–70°C; preferably 40–60°C; more preferably 50–55°C.

[0084] The secondary drying humidity can be 60-90%; preferably 70-85%; more preferably 75-80%.

[0085] The secondary drying time can be 8 to 48 hours; preferably 12 to 36 hours; more preferably 15 to 24 hours.

[0086] The drying temperature for the three drying stages can be 100–140°C; preferably 110–130°C; more preferably 120–125°C.

[0087] The humidity level can be 80-95% for the three drying cycles; preferably 85-90%.

[0088] The drying time for the three drying cycles can be 8 to 48 hours; preferably 12 to 36 hours; more preferably 15 to 24 hours.

[0089] roasting steps

[0090] The dried green body was calcined to obtain the catalyst.

[0091] The roasting temperature can be 400–650℃; preferably 450–600℃; more preferably 500–550℃.

[0092] The roasting time can be 5 to 12 hours; preferably 7 to 10 hours; more preferably 8 to 9 hours.

[0093] <Uses of Catalysts>

[0094] The catalyst of this invention exhibits high catalytic oxidation efficiency for CO. Therefore, this invention provides the use of the above-described catalyst in the catalytic oxidation of CO. CO can be present in flue gas.

[0095] The concentration of CO in the flue gas can be 3000–15000 ppm; preferably 8000–15000 ppm; more preferably 10000–12000 ppm.

[0096] The concentration of NO in flue gas can be less than or equal to 800 ppm. For example, 200–400 ppm; or 300–350 ppm.

[0097] The concentration of SO2 in the flue gas can be less than or equal to 100 ppm. In some embodiments, it is 30–70 ppm. In other embodiments, it is 40–60 ppm.

[0098] The water vapor content in the flue gas can be 2-20 vol; preferably 5-15 vol; more preferably 10-12 vol.

[0099] The CO2 content in the flue gas can be 2-20 vol; preferably 5-15 vol; more preferably 10-12 vol.

[0100] The catalytic oxidation temperature can be 80–350°C; preferably 120–300°C; more preferably 150–250°C.

[0101] The testing method is described below:

[0102] CO Catalytic Efficiency and Stabilization Time: 30g of catalyst was placed in a fixed-bed reactor for catalyst activity evaluation. The total inlet flue gas flow rate was 5L. The inlet flue gas composition was: CO concentration 11000ppm, NO concentration 300ppm, SO2 concentration 50ppm, CO2 content 10vol%, and water vapor content 10vol%. The test temperature was 180℃, and the space velocity was 12000h⁻¹. -1 .

[0103] The CO content in the outlet flue gas was determined using an industrial flue gas analyzer manufactured by MRU GmbH, Germany, and the CO catalytic efficiency was calculated.

[0104] The recording time is stopped when the CO content in the outlet flue gas shows a fluctuating upward trend. The time minus the time at the start of the catalyst activity evaluation is the stabilization time.

[0105] Example 1

[0106] 70 parts by weight of titanium dioxide, 10 parts by weight of aluminum oxide, 10 parts by weight of manganese oxide, 5 parts by weight of silicon carbide powder, 3 parts by weight of activated carbon powder, 2 parts by weight of magnesium sulfate, 5 parts by weight of wood shell powder and 3 parts by weight of starch were mixed at 25°C and 450 rpm for 30 min to obtain the first mixture.

[0107] The first mixture, 1.13 parts by weight of molybdenum oxide, and 3.75 parts by weight of copper oxide were mixed at 25°C and 450 rpm for 30 min to obtain the second mixture.

[0108] The second mixture was mixed with the active salt solution at 25°C and 400 rpm for 30 min, then the temperature was raised to 60°C and mixing continued for 15 min to obtain the third mixture. The active salt solution consisted of 7.5 parts by weight of cerium acetate (calculated as cerium oxide), 1.12 parts by weight of ammonium metatungstate (calculated as tungsten trioxide), 1.5 parts by weight of lanthanum nitrate (calculated as lanthanum oxide), and 18 parts by weight of water. The active salt solution was added to the second mixture in three portions.

[0109] 15 parts by weight of glass fiber powder were added to the third mixture in three portions and mixed for 60 minutes at a temperature of 60°C and a rotation speed of 350 rpm to obtain the fourth mixture.

[0110] Two parts by weight of hydroxypropyl methylcellulose were added to the fourth mixture and mixed for 30 min at a temperature of 60°C and a rotation speed of 350 rpm. Then, 2.5 parts by weight of glycerol and 2.5 parts by weight of ethanolamine were added and mixed for 30 min at a temperature of 60°C and a rotation speed of 400 rpm to obtain catalyst sludge.

[0111] The catalyst sludge was aged at 35℃ and 60% humidity for 24 hours to obtain aged sludge. The aged sludge was then mixed three times in a vacuum ply mill to remove air from its interior, resulting in a mixed sludge. The mixed sludge was then formed using a honeycomb extruder to obtain a honeycomb-shaped catalyst preform.

[0112] The catalyst preform was dried once at 35℃ and 60% humidity for 18 hours, then dried a second time at 50℃ and 75% humidity for 24 hours, and finally dried a third time at 120℃ and 90% humidity for 24 hours to obtain a dried preform.

[0113] The dried preform was calcined in a muffle furnace at 500°C for 8 hours to obtain the catalyst.

[0114] The properties of the obtained catalyst are shown in Table 1.

[0115] Comparative Example 1

[0116] Except that the amounts of titanium dioxide (30 parts by weight), aluminum oxide (18 parts by weight), manganese oxide (18 parts by weight), silicon carbide powder (13 parts by weight), activated carbon powder (11 parts by weight), and magnesium sulfate (10 parts by weight) are the same as in Example 1.

[0117] The properties of the obtained catalyst are shown in Table 1.

[0118] Comparative Example 2

[0119] Except that the amounts of titanium dioxide (50 parts by weight), aluminum oxide (14 parts by weight), manganese oxide (14 parts by weight), silicon carbide powder (9 parts by weight), activated carbon powder (7 parts by weight), and magnesium sulfate (6 parts by weight) are the same as in Example 1.

[0120] The properties of the obtained catalyst are shown in Table 1.

[0121] Comparative Example 3

[0122] Except that the amount of molybdenum oxide is 1.87 parts by weight, the amount of copper oxide is 2.63 parts by weight, and the active salt solution is composed of 7.5 parts by weight of cerium acetate (calculated as cerium oxide), 1.88 parts by weight of ammonium metatungstate (calculated as tungsten trioxide), 1.12 parts by weight of lanthanum nitrate (calculated as lanthanum oxide) and 18 parts by weight of water, the rest is the same as in Example 1.

[0123] The properties of the obtained catalyst are shown in Table 1.

[0124] Comparative Example 4

[0125] Except that the amount of molybdenum oxide is 2.1 parts by weight, the amount of copper oxide is 3.6 parts by weight, and the active salt solution is composed of 6 parts by weight of cerium acetate (calculated as cerium oxide), 1.5 parts by weight of ammonium metatungstate (calculated as tungsten trioxide), 1.8 parts by weight of lanthanum nitrate (calculated as lanthanum oxide) and 18 parts by weight of water, the rest is the same as in Example 1.

[0126] The properties of the obtained catalyst are shown in Table 1.

[0127] Table 1

[0128] Example 1 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 CO catalytic efficiency (%) 98.6 90 92 88 84.7 Settling time (h) 78 72 75.5 90 94.5

[0129] As shown in Example 1 and Comparative Examples 1-2, the amounts of titanium dioxide, alumina, manganese oxide, silicon carbide powder, activated carbon powder, and magnesium sulfate have a significant impact on the catalytic efficiency of the catalyst for CO. The catalytic efficiency and stabilization time of Comparative Examples 1 and 2 are both lower than those of Example 1.

[0130] As demonstrated in Examples 1 and Comparative Examples 3-4, the amounts of molybdenum oxide, copper oxide, cerium acetate, ammonium metatungstate, and lanthanum nitrate have a significant impact on the catalytic efficiency of the catalyst for CO. The catalytic efficiencies of Comparative Examples 3 and 4 are significantly lower than those of Example 1.

[0131] This invention is not limited to the above-described embodiments. Any modifications, improvements, or substitutions that can be conceived by those skilled in the art without departing from the essential content of this invention fall within the scope of this invention.

Claims

1. A catalyst for the catalytic oxidation of CO, characterized in that, The catalyst is prepared from raw materials comprising the following composition: 60-95 parts by weight of titanium dioxide, 1-20 parts by weight of aluminum oxide, 5-25 parts by weight of manganese oxide, 1-15 parts by weight of silicon carbide, 0.5-8 parts by weight of activated carbon, and 0.1-5 parts by weight of magnesium sulfate; The precursors are: 6.5 to 9 parts by weight of cerium oxide, 0.7 to 1.4 parts by weight of tungsten oxide, 0.7 to 1.7 parts by weight of molybdenum oxide, 3.5 to 4.5 parts by weight of copper oxide, and 1.2 to 1.7 parts by weight of lanthanum oxide. The amount of cerium oxide precursor used is calculated as cerium oxide, the amount of tungsten oxide precursor used is calculated as tungsten trioxide, the mass of molybdenum oxide precursor is calculated as molybdenum oxide, the mass of copper oxide precursor is calculated as copper oxide, and the mass of lanthanum oxide precursor is calculated as lanthanum oxide.

2. The catalyst according to claim 1, characterized in that, The raw materials also include 1 to 10 parts by weight of pore-forming agent, 0.5 to 5 parts by weight of binder, 0.5 to 7 parts by weight of internal lubricant, 1 to 10 parts by weight of external lubricant and 5 to 25 parts by weight of structural reinforcing agent.

3. The catalyst according to claim 2, characterized in that, The pore-forming agent is wood shell powder, the binder is hydroxypropyl methylcellulose, the internal lubricant is starch, the external lubricant is a mixture of glycerol and ethanolamine, and the structural reinforcing agent is glass fiber.

4. The catalyst according to claim 2, characterized in that, The cerium oxide precursor is a water-soluble cerium salt, the tungsten oxide precursor is a water-soluble tungstate, the molybdenum oxide precursor is molybdenum oxide, the copper oxide precursor is copper oxide, and the lanthanum oxide precursor is a water-soluble lanthanum salt.

5. The catalyst according to any one of claims 1 to 4, characterized in that, The catalyst is a honeycomb catalyst.

6. The method for preparing the catalyst according to any one of claims 1 to 5, characterized in that, Includes the following steps: (1) Forming catalyst sludge from raw materials; (2) The catalyst sludge is aged to obtain aged sludge; the aged sludge is mixed to obtain mixed sludge; the mixed sludge is extruded to obtain a honeycomb-shaped catalyst blank; (3) Dry the honeycomb-shaped catalyst preform to obtain a dried preform; (4) The dried green body is calcined to obtain the catalyst.

7. The preparation method according to claim 6, characterized in that, The aging process is carried out at a temperature of 25–45℃ and a humidity of 40–70% for 18–35 hours. The roasting temperature is 400–650℃, and the roasting time is 5–12 hours.

8. The preparation method according to claim 6, characterized in that, The catalyst preform is dried once at a temperature of 25–45°C and a humidity of 40–75%, then dried a second time at a temperature of 35–70°C and a humidity of 60–90%, and finally dried a third time at a temperature of 100–140°C and a humidity of 80–95%.

9. The preparation method according to claim 6, characterized in that, The catalyst is the catalyst according to claim 4, and step (1) includes the following steps: (a) Titanium dioxide, aluminum oxide, manganese oxide, silicon carbide, activated carbon, magnesium sulfate, pore-forming agent and internal lubricant are mixed to obtain a first mixture; (b) The first mixture, the molybdenum oxide precursor, and the copper oxide precursor are mixed to obtain a second mixture; (c) The second mixture is mixed with an active salt solution comprising cerium oxide precursor, tungsten oxide precursor, lanthanum oxide precursor and water to obtain a third mixture; (d) The third mixture and the structural reinforcing agent are mixed to obtain the fourth mixture; (e) The fourth mixture is mixed with the binder and then with the external lubricant to obtain the catalyst slurry.

10. Use of the catalyst according to any one of claims 1 to 5 in the catalytic oxidation of CO.