Catalyst for cooperatively treating CO and NOX in flue gas and preparation method thereof
A catalyst composed of W, V, Cu, Mn, Ce, and Fe, optionally with Mo, supports efficient simultaneous removal of CO and NOX from flue gas, addressing the complexity and cost of separate treatment methods by achieving high removal efficiencies without additional infrastructure.
Patent Information
- Application Number
- CN202510043375.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-10
- Publication Date
- 2025-04-25
AI Technical Summary
Current industrial processes face challenges in efficiently and simultaneously removing CO and NOX from flue gas, as existing technologies often require separate treatment methods, leading to complex and costly pollution control systems.
A catalyst comprising specific ratios of W, V, Cu, Mn, Ce, and Fe, optionally with Mo, supported on TiO2, SiO2, or Al2O3, is used to co-remove CO and NOX by forming a catalyst that achieves high removal efficiencies at temperatures between 220-240°C.
The catalyst achieves over 95% removal of NOX and 92% oxidation of CO, requiring no additional equipment investment by replacing existing NOX removal systems, thus simplifying and enhancing the efficiency of pollution control.
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Abstract
Description
Technical Field
[0001] The invention belongs to the field of catalysts and relates to a method for coordinating the treatment of flue gas, especially carbon monoxide (CO) and nitrogen oxides (NO X ) catalyst and a method for preparing the same. Background Art
[0002] As the world's environmental problems become increasingly prominent, air pollution caused by industrial releases has received widespread attention. NOx is an important precursor of PM2.5 and photochemical smog, and is the most environmentally problematic atmospheric pollutant that can cause acid rain and damage the ozone layer, polluting the environment. CO is also an extremely unfriendly environmental pollutant. CO is both a toxic gas and a common fuel. Direct emissions not only cause energy waste, but also have a negative impact on human health and the atmospheric environment.
[0003] NO in coke oven flue gas X The content is about 1000mg / Nm 3 , CO content is 0.1%-0.3%. At present, the environmental protection facilities for coke oven flue gas only have desulfurization, denitrification and dust removal, but no CO removal. The emission of CO in flue gas must also be controlled. At present, the control of pollutants in flue gas mostly adopts single removal technology. With the continuous increase in the types of pollutant control, the pollutant purification equipment continues to expand. Both the investment and operation costs and the complexity of the purification system are facing great difficulties. Therefore, the development of efficient and multi-pollutant synergistic removal technology has become a current research hotspot. Summary of the invention
[0004] [Technical issues]
[0005] The purpose of the present invention is to provide a method for coordinating the treatment of CO and NO in flue gas. X Catalyst and preparation method thereof for efficient and coordinated removal of CO and NO from flue gas X .
[0006] [Technical solution]
[0007] According to one aspect of the present invention, a catalyst is provided, which can synergistically remove CO and NO from flue gas. X .
[0008] According to the present invention, the catalyst comprises a carrier and an active component, wherein the active component comprises tungsten (W), vanadium (V), copper (Cu), manganese (Mn), cerium (Ce), and iron (Fe), wherein, based on the molar amount of manganese,
[0009] The molar amount of tungsten is 0.01-0.10, the molar amount of vanadium is 0.1-0.5, the molar amount of copper is 0.1-0.8, the molar amount of cerium is 0.01-0.09, and the molar amount of iron is 0.05-0.2.
[0010] According to the present invention, in some embodiments, the active ingredient further comprises molybdenum (Mo), wherein the molar amount of molybdenum is 0.01-0.15 based on the molar amount of manganese.
[0011] According to the present invention, in some embodiments, the active ingredients in the catalyst are composed of tungsten (W), vanadium (V), copper (Cu), manganese (Mn), cerium (Ce), and iron (Fe); in other embodiments, the active ingredients in the catalyst are composed of tungsten (W), molybdenum (Mo), vanadium (V), copper (Cu), manganese (Mn), cerium (Ce), and iron (Fe).
[0012] According to the present invention, in some embodiments, based on the molar amount of manganese, the molar amount of tungsten is 0.03-0.10, such as 0.05, 0.07, 0.09, etc.
[0013] According to the present invention, in some embodiments, based on the molar amount of manganese, the molar amount of molybdenum is 0.03-0.15, such as 0.05, 0.07, 0.09, 0.11, 0.13, etc.
[0014] According to the present invention, in some embodiments, based on the molar amount of manganese, the molar amount of vanadium is 0.2-0.5, such as 0.3, 0.4, etc.
[0015] According to the present invention, in some embodiments, based on the molar amount of manganese, the molar amount of copper is 0.2-0.8, such as 0.3, 0.4, 0.5, 0.6, 0.7, etc.
[0016] According to the present invention, in some embodiments, based on the molar amount of manganese, the molar amount of cerium is 0.03-0.09, such as 0.05, 0.07, 0.08.
[0017] According to the present invention, in some embodiments, based on the molar amount of manganese, the molar amount of iron is 0.07-0.2, such as 0.09, 0.12, 0.15, 0.18, etc.
[0018] According to the present invention, in some embodiments, the molar amount of the carrier is 1-15, such as 2, 5, 7, 9, 12, etc., based on the molar amount of manganese.
[0019] According to the present invention, in some embodiments, the carrier is selected from titanium dioxide (TiO2), silicon dioxide (SiO2), and aluminum oxide (Al2O3).
[0020] According to another aspect of the present invention, a method for co-processing CO and NO in flue gas is provided. X A method for preparing a catalyst, the method comprising:
[0021] Dissolve water-soluble metatungstate or tungstate in water to obtain solution A; or dissolve water-soluble metatungstate or tungstate and water-soluble molybdate in water respectively, and mix the two to obtain solution A;
[0022] Dissolve water-soluble metavanadate or vanadate in water, heat at 80-90°C, dropwise add ethanolamine as a cosolvent, continue stirring until the solution becomes transparent, and mix the solution with solution A to obtain solution B;
[0023] Put water-soluble salts of copper, manganese, cerium and iron into a container, add water to dissolve them, and obtain solution C;
[0024] After mixing solution B and solution C, the carrier is added and the mixture is made viscous at 40-50° C.; the obtained viscous solid is dried, then calcined at 400-500° C. for 3-5 hours, and cooled to obtain the catalyst.
[0025] According to the present invention, in the method, the catalyst obtained after calcination can be further tableted, crushed, and sieved to a 40-60 mesh catalyst.
[0026] According to the present invention, in some embodiments, the metatungstate or tungstate is selected from ammonium metatungstate, ammonium tungstate; and / or,
[0027] The molybdate is ammonium heptamolybdate; and / or
[0028] The metavanadate or polyvanadate is selected from ammonium metavanadate and ammonium polyvanadate; and / or,
[0029] The water-soluble salts of copper, manganese, cerium and iron are respectively selected from their nitrates.
[0030] According to the present invention, if the above salts exist as hydrates, the scope also covers the corresponding hydrates. For example, copper nitrate may include copper nitrate trihydrate, cerium nitrate may include cerium nitrate hexahydrate, and iron nitrate may include iron nitrate nonahydrate.
[0031] According to the present invention, in some embodiments, the pH value of solution C is controlled to be 2-3. For example, when preparing solution C, a small amount of HNO3 aqueous solution can be added to control the pH value.
[0032] According to the present invention, in some embodiments, during the calcination process, the temperature is increased to the calcination temperature at a rate of 5-10° C. / min.
[0033] According to the present invention, in some embodiments, when dissolving the water-soluble salt, hot water at 80-90° C. can be used for dissolution according to the situation.
[0034] According to the present invention, in some embodiments, when preparing solution C, the water-soluble salt of manganese can be first dissolved in water to form a solution, and then added into a container together with other water-soluble salts of copper, cerium and iron to dissolve.
[0035] According to the present invention, in some embodiments, the water used may be deionized water.
[0036] According to the present invention, in some embodiments, the carrier is selected from titanium dioxide (TiO2), silicon dioxide (SiO2), and aluminum oxide (Al2O3).
[0037] According to the present invention, in one embodiment, the method comprises:
[0038] Dissolve ammonium metatungstate in water to obtain solution A; or dissolve ammonium metatungstate and ammonium heptamolybdate in water respectively, and mix the two to obtain solution A;
[0039] Dissolve ammonium metavanadate in water and heat it in a water bath at 80-90°C, add a small amount of ethanolamine as a co-solvent, and continue stirring until the solution becomes transparent. Mix this solution with solution A to obtain solution B;
[0040] Put copper nitrate trihydrate, manganese nitrate, cerium nitrate hexahydrate and iron nitrate nonahydrate into a container, add 200 ml of deionized water to dissolve, and obtain solution C;
[0041] After mixing solution B and solution C, add TiO2 and make them all viscous at 40-50°C; put the obtained viscous solid into an oven for drying, then put it into a muffle furnace, heat it to 400-500°C at a rate of 5-10°C / min, roast it at 400-500°C for 3-5 hours, and then cool it naturally to room temperature.
[0042] According to the method of the present invention, in one embodiment, in the method, based on the weight of the carrier,
[0043] The weight percentage of metatungstate or tungstate (e.g. ammonium metatungstate) is 1-5%, e.g. 2%, 3%, 4%;
[0044] The weight percentage of molybdate (e.g. ammonium heptamolybdate) is 1-5%, e.g. 2%, 3%, 4%;
[0045] The weight percentage of metavanadate or polyvanadate (e.g. ammonium metavanadate) is 3-6%, e.g. 3%, 4%, 5%;
[0046] The weight percentage of the water-soluble salt of copper (e.g. copper nitrate trihydrate) is 5-25%, such as 6%, 7%, 8%, 9%, 10%, 15%, 20%;
[0047] The weight percentage of water-soluble salt of manganese (e.g., manganese nitrate) is 1-5%, e.g., 2%, 3%, 4%;
[0048] The weight percentage of the water-soluble salt of cerium (e.g., cerium nitrate hexahydrate) is 1-5%, such as 2%, 3%, 4%;
[0049] The weight percentage of the water-soluble salt of iron (eg, ferric nitrate nonahydrate) is 1-15%, such as 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%.
[0050] The catalyst prepared according to the method of the present invention is as described above and will not be described in detail here.
[0051] [Technical Effect]
[0052] The catalyst according to the present invention has a NOx removal rate of more than 95% and a CO oxidation removal rate of more than 92% within a temperature range of 220-240°C, and has excellent performance in synergistic removal of NOx and CO.
[0053] The catalyst according to the present invention can effectively remove NO in flue gas at the same time X And CO, at the same time, only need to replace the catalyst on the original denitration device with the synergistic catalyst of the present invention, without any additional equipment investment, can effectively remove the two pollutants. BRIEF DESCRIPTION OF THE DRAWINGS
[0054] Figure 1 The process of evaluating the catalyst for removing NOx and CO from flue gas in the present application is schematically shown.
[0055] Figure 2 The evaluation results of removing NOx and CO from flue gas using the catalyst prepared in Example 1 are shown.
[0056] Figure 3 The evaluation results of removing NOx and CO from flue gas using the catalyst prepared in Example 2 are shown. DETAILED DESCRIPTION
[0057] The following examples are only listed as examples of embodiments of the present invention and do not constitute any limitation to the present invention. It can be understood by those skilled in the art that modifications within the scope of the essence and concept of the present invention fall within the scope of protection of the present invention. Unless otherwise specified, the reagents and instruments used in the following examples are all commercially available products.
[0058] Example 1
[0059] (1) First, weigh 0.32 g of ammonium metatungstate powder and dissolve it in 30 ml of water (80-90° C.) to form an aqueous solution.
[0060] (2) Weigh 0.72 g of ammonium heptamolybdate powder and dissolve it in 30 ml of hot water (80-90° C.) to form an aqueous solution.
[0061] The solutions obtained in (1) and (2) above were mixed and named solution A.
[0062] (3) Weigh 0.90 g of ammonium metavanadate and dissolve it in deionized water. Heat it in a water bath at 80-90°C, dropwise add a small amount of ethanolamine as a co-solvent, and continue stirring until the solution becomes transparent, i.e., the ammonium metavanadate is completely dissolved, to obtain a solution. The obtained solution is mixed with solution A and named solution B.
[0063] (4) Take 3.98 g of copper nitrate trihydrate, 11.79 g of 50% manganese nitrate aqueous solution, 0.72 g of cerium nitrate hexahydrate and 1.33 g of ferric nitrate nonahydrate, put them into a beaker, add 200 ml of deionized water, then add a small amount of HNO3 aqueous solution, stir gently, and make the pH of the mixed solution reach 2-3. Name it solution C.
[0064] (5) After mixing solutions B and C, 18.2 g of TiO2 was added and the mixture was made viscous at 40°C. The obtained viscous solid was dried in an oven, then placed in a muffle furnace, heated to 400°C at a rate of 5-10°C / min, calcined at 400°C for 3 hours, and then naturally cooled to room temperature.
[0065] (6) Tablet, crush, and sieve the catalyst to 40-60 mesh for later use.
[0066] Example 2
[0067] (1) First, weigh 0.4 g of ammonium metatungstate powder and dissolve it in 30 ml of hot water (80-90° C.) to form an aqueous solution, named solution A.
[0068] (2) Weigh 0.80 g of ammonium metavanadate and dissolve it in deionized water. Heat it in a water bath at 80-90° C., add a small amount of ethanolamine as a cosolvent, and continue stirring until the solution becomes transparent, i.e., the ammonium metavanadate is completely dissolved, to obtain a solution.
[0069] The solution obtained in (2) was mixed with solution A and named solution B.
[0070] (4) 3 g of copper nitrate trihydrate, 10 g of 50% manganese nitrate aqueous solution, 0.6 g of cerium nitrate hexahydrate and 1 g of iron nitrate nonahydrate were placed in a beaker and added with 200 ml of deionized water. A small amount of HNO3 aqueous solution was then added and stirred gently until the pH of the mixture reached 2-3. This mixture was named Solution C.
[0071] (5) After mixing solutions B and C, 19 g of TiO2 was added and the mixture was made viscous at 40°C. The obtained viscous solid was dried in an oven, then placed in a muffle furnace, heated to 400°C at a rate of 5-10°C / min, calcined at 400°C for 3 hours, and then naturally cooled to room temperature.
[0072] (6) Tablet, crush, and sieve the catalyst to 40-60 mesh for later use.
[0073] Example 3
[0074] (1) First, weigh 0.5 g of ammonium metatungstate powder and dissolve it in 30 ml of hot water (80-90° C.) to form an aqueous solution.
[0075] (2) Weigh 0.2 g of ammonium heptamolybdate powder and dissolve it in 30 ml of hot water (80-90° C.) to form an aqueous solution.
[0076] The solutions obtained in (1) and (2) above were mixed and named solution A.
[0077] (3) Weigh 0.90 g of ammonium metavanadate and dissolve it in deionized water. Heat it in a water bath at 80-90° C., add a small amount of ethanolamine as a cosolvent, and continue stirring until the solution becomes transparent, i.e., the ammonium metavanadate is completely dissolved, to obtain a solution.
[0078] The solution obtained in (3) was mixed with solution A and named solution B.
[0079] (4) 3 g of copper nitrate trihydrate, 9 g of 50% manganese nitrate solution, 0.8 g of cerium nitrate hexahydrate and 1.5 g of iron nitrate nonahydrate were placed in a beaker and added with 200 ml of deionized water. A small amount of HNO3 aqueous solution was then added and stirred gently until the pH of the mixture reached 2-3. This mixture was named Solution C.
[0080] (5) After mixing solutions B and C, add 20 g of TiO2 and make the whole solution viscous at 40°C. Dry the obtained viscous solid in an oven, then put it in a muffle furnace, heat it to 400°C at a rate of 5-10°C / min, calcine it at 400°C for 3 hours, and then cool it naturally to room temperature.
[0081] (6) Tablet, crush, and sieve the catalyst to 40-60 mesh for later use.
[0082] Example 4
[0083] (1) First, weigh 0.6 g of ammonium metatungstate powder and dissolve it in 30 ml of hot water (80-90° C.) to form an aqueous solution, named solution A.
[0084] (2) Weigh 0.85 g of ammonium metavanadate and dissolve it in deionized water. Heat it in a water bath at 80-90° C., add a small amount of ethanolamine as a cosolvent, and continue stirring until the solution becomes transparent, i.e., the ammonium metavanadate is completely dissolved, to obtain a solution.
[0085] The solution obtained in (2) was mixed with solution A and named solution B.
[0086] (3) 4.2 g of copper nitrate trihydrate, 13 g of 50% manganese nitrate solution, 0.5 g of cerium nitrate hexahydrate and 2 g of iron nitrate nonahydrate were placed in a beaker and added with 200 ml of deionized water. A small amount of HNO3 aqueous solution was then added and stirred gently until the pH of the mixture reached 2-3. This mixture was named Solution C.
[0087] (4) After mixing solutions B and C, 19 g of TiO2 was added and the mixture was made viscous at 40°C. The obtained viscous solid was dried in an oven, then placed in a muffle furnace, heated to 400°C at a rate of 5-10°C / min, calcined at 400°C for 3 hours, and then naturally cooled to room temperature.
[0088] (5) Tablet, crush, and sieve the catalyst to 40-60 mesh for later use.
[0089] Test example
[0090] Catalyst test evaluation process:
[0091] Figure 1 The process of evaluating the catalyst for removing NOx and CO from flue gas in the present application is schematically shown.
[0092] like Figure 1 As shown, the prepared catalyst sample is placed in a quartz glass tube reactor, the reactor is placed in a program-controlled temperature reactor, the temperature in the reactor is set according to the test requirements, and the outlet indicators are detected by a flue gas analyzer (Testo 750 flue gas analyzer), as follows:
[0093] Step 1: Fill the screened catalyst to 1.9cm; Step 2: Turn on the temperature controller, set the initial reaction temperature to 180℃, and gradually increase the temperature according to the export indicators in the later stage; Step 3: Start gas distribution, after calculation, configure the standard gas of CO and NO, the total gas flow rate is 1000ml / min, and the inlet CO concentration is detected to be 1600ppm and the NO concentration is 320ppm; Step 4: Detect the outlet gas concentration, gradually increase the reaction temperature to 250℃, record the outlet NO and CO concentrations every five minutes, and record the outlet NO and CO concentrations at different temperatures.
[0094] Figure 2 The evaluation results of removing NOx and CO from flue gas using the catalyst prepared in Example 1 above are shown.
[0095] The experimental results show that the synergistic removal efficiency of the catalyst prepared in Example 1 increases with increasing temperature. At 220°C, the denitration efficiency reaches 97%, and the CO oxidation removal rate reaches 95%.
[0096] Figure 3 The evaluation results of removing NOx and CO from flue gas using the catalyst prepared in Example 2 above are shown.
[0097] The experimental results show that the synergistic removal efficiency of the catalyst prepared in Example 2 increases with increasing temperature. At 230°C, the catalyst denitration efficiency is close to 100%, and the CO oxidation removal rate reaches 95%.
[0098] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.
Claims
1. A method for synergistically removing CO and NO from flue gas X A catalyst characterized in that The catalyst comprises a carrier and an active component, wherein the active component comprises tungsten (W), vanadium (V), copper (Cu), manganese (Mn), cerium (Ce), and iron (Fe). Where, based on the molar amount of manganese, The molar amount of tungsten is 0.01-0.10, the molar amount of vanadium is 0.1-0.5, the molar amount of copper is 0.1-0.8, the molar amount of cerium is 0.01-0.09, and the molar amount of iron is 0.05-0.
2.
2. The catalyst according to claim 1, wherein The active ingredient further includes molybdenum (Mo), wherein the molar amount of molybdenum is 0.01-0.15 based on the molar amount of manganese.
3. The catalyst according to claim 1 or 2, wherein Based on the molar amount of manganese, The molar amount of tungsten is 0.03-0.10; and / or The molar amount of molybdenum is 0.03-0.15; and / or The molar amount of vanadium is 0.2-0.5; and / or The molar amount of copper is 0.2-0.8; and / or The molar amount of cerium is 0.03-0.09; and / or The molar amount of iron is 0.07-0.2; and / or The molar amount of the carrier is 1-15.
4. A method for co-processing CO and NO in flue gas X A method for preparing a catalyst, the method comprising: Dissolve water-soluble metatungstate or tungstate in water to obtain solution A; Alternatively, water-soluble metatungstate or tungstate and water-soluble molybdate are dissolved in water respectively, and the two are mixed to obtain solution A; Dissolve water-soluble metavanadate or vanadate in water, heat at 80-90°C, dropwise add ethanolamine as a cosolvent, continue stirring until the solution becomes transparent, and mix the solution with solution A to obtain solution B; Put water-soluble salts of copper, manganese, cerium and iron into a container, add water to dissolve them, and obtain solution C; After mixing solution B and solution C, add the carrier and make them all viscous at 40-50°C; dry the obtained viscous solid, then roast at 400-500°C for 3-5 hours, and cool to obtain the catalyst. Optionally, after calcination, the obtained catalyst is further tableted, crushed, and sieved to a 40-60 mesh catalyst.
5. The preparation method according to claim 4, wherein The metatungstate or tungstate is selected from ammonium metatungstate and ammonium tungstate; and / or, The molybdate is ammonium heptamolybdate; and / or The metavanadate or polyvanadate is selected from ammonium metavanadate and ammonium polyvanadate; and / or, The water-soluble salts of copper, manganese, cerium and iron are respectively selected from their nitrates.
6. The preparation method according to claim 4 or 5, wherein: In the method, The pH value of solution C is controlled to be 2-3; and / or When preparing solution C, the water-soluble salt of manganese is first dissolved in water to form a solution, and then added into a container together with other water-soluble salts of copper, cerium and iron to dissolve.
7. The preparation method according to any one of claims 4 to 6, wherein: In the calcination process of the method, the temperature is raised to the calcination temperature at a rate of 5-10° C. / min.
8. The preparation method according to any one of claims 4 to 7, wherein: In the method, the carrier is selected from titanium dioxide (TiO2), silicon dioxide (SiO2), and aluminum oxide (Al2O3).
9. The preparation method according to any one of claims 4 to 8, wherein In the method, Dissolve ammonium metatungstate in water to obtain solution A; or dissolve ammonium metatungstate and ammonium heptamolybdate in water respectively, and mix the two to obtain solution A; Dissolve ammonium metavanadate in water and heat it in a water bath at 80-90°C, add a small amount of ethanolamine as a co-solvent, and continue stirring until the solution becomes transparent. Mix this solution with solution A to obtain solution B; Put copper nitrate trihydrate, manganese nitrate, cerium nitrate hexahydrate and iron nitrate nonahydrate into a container, add 200 ml of deionized water to dissolve, and obtain solution C; After mixing solution B and solution C, add TiO2 and make them all viscous at 40-50°C; put the obtained viscous solid into an oven for drying, then put it into a muffle furnace, heat it to 400-500°C at a rate of 5-10°C / min, roast it at 400-500°C for 3-5 hours, and then cool it naturally to room temperature.
10. The preparation method according to any one of claims 4 to 9, wherein In the method, based on the weight of the carrier, The weight percentage of metatungstate or tungstate is 1-5%; The weight percentage of molybdate is 1-5%; The weight percentage of metavanadate or polyvanadate is 3-6%; The weight percentage of water-soluble salt of copper is 5-25%; The weight percentage of water-soluble salt of manganese is 1-5%; The weight percentage of the water-soluble salt of cerium is 1-5%; The weight percentage of the water-soluble salt of iron is 1-15%.