CN115869940B - Method for preparing low-temperature denitration catalyst by utilizing titanium-based waste denitration catalyst and low-temperature denitration catalyst - Google Patents
Method for preparing low-temperature denitration catalyst by utilizing titanium-based waste denitration catalyst and low-temperature denitration catalyst Download PDFInfo
- Publication number
- CN115869940B CN115869940B CN202310214589.4A CN202310214589A CN115869940B CN 115869940 B CN115869940 B CN 115869940B CN 202310214589 A CN202310214589 A CN 202310214589A CN 115869940 B CN115869940 B CN 115869940B
- Authority
- CN
- China
- Prior art keywords
- denitration catalyst
- temperature
- acid solution
- solution
- catalyst
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Landscapes
- Catalysts (AREA)
- Exhaust Gas Treatment By Means Of Catalyst (AREA)
Abstract
The invention relates to the technical field of recycling of waste denitration catalysts, and discloses a method for preparing a low-temperature denitration catalyst by utilizing a titanium-based waste denitration catalyst and the low-temperature denitration catalyst. The method comprises the following steps: (1) Soaking the waste denitration catalyst in an acid solution, washing, drying and crushing; (2) Placing the catalyst powder into an alkali solution for reaction, and drying filter residues after solid-liquid separation; (3) Placing filter residues in an acid solution for reaction, taking an upper layer solid-liquid mixture for centrifugation, and drying to obtain a titanium slag carrier; (4) Placing the titanium slag carrier in water, adding a manganese source and an auxiliary agent source, regulating the pH value of the solution to 9-10, standing, performing solid-liquid separation, drying the obtained solid, and roasting to obtain the denitration catalyst. According to the method, part of titanium dioxide and part of vanadium and tungsten in the waste denitration catalyst are recovered to obtain titanium slag, so that the titanium slag has good hydrophilicity, mn and auxiliary agents are loaded, and the low-temperature denitration catalyst with good denitration activity is obtained.
Description
Technical Field
The invention relates to the technical field of recycling of waste denitration catalysts, in particular to a method for preparing a low-temperature denitration catalyst by utilizing a titanium-based waste denitration catalyst and the low-temperature denitration catalyst.
Background
NH 3 SCR is an important denitration technology in the field of coal burning at present, and the catalyst is NH 3 The key to SCR. After long-time use, the denitration catalyst is deactivated, and the deactivated denitration catalyst becomes waste after being unable to be regenerated. However, these wastes still contain a large amount of titanium dioxide, which still has a certain performance and value. Meanwhile, titanium dioxide has a wide application range as a catalyst.
The traditional denitration catalyst has narrower application temperature and is concentrated in a medium-high temperature section, but the medium-high temperature denitration catalyst has larger defects in the application process in the denitration field of power plants and the like, and the energy consumption is definitely improved. Mn-based denitration catalysts are typical low-temperature catalysts and have a large application market.
Disclosure of Invention
The invention aims to solve the problem that titanium dioxide in a waste denitration catalyst is not effectively utilized in the prior art, and provides a method for preparing a low-temperature denitration catalyst by utilizing a titanium-based waste denitration catalyst and the low-temperature denitration catalyst.
In order to achieve the above object, the present invention provides in one aspect a method for preparing a low temperature denitration catalyst using a titanium-based waste denitration catalyst, the method comprising the steps of:
(1) Soaking the waste denitration catalyst in an acid solution, washing, drying, and then crushing;
(2) Placing the catalyst powder obtained in the step (1) into an alkali solution for reaction, and drying filter residues after solid-liquid separation;
(3) Placing filter residues in an acid solution for reaction, then taking an upper layer solid-liquid mixture for centrifugation, and drying to obtain a titanium slag carrier;
(4) Placing the titanium slag carrier in water, adding a manganese source and an auxiliary agent source, regulating the pH value of the solution to 9-10, standing, performing solid-liquid separation, drying the obtained solid, and roasting to obtain the low-temperature denitration catalyst.
Preferably, in step (1), the acid solution is a citric acid solution and/or an oxalic acid solution; the concentration of the acid solution is 0.5-2mol/L; and/or
The soaking time is 20-60 minutes.
Preferably, in step (1), the particles are crushed to a particle size of less than 100 mesh.
Preferably, in step (2), the alkali solution is a sodium hydroxide solution and/or a potassium hydroxide solution, the concentration of the alkali solution being 5-40 wt%; and/or
In step (2), the reaction conditions include: the temperature is 80-120 ℃, the time is more than 0.5h, and the liquid-solid ratio is 5-30:1mL/g.
Preferably, in step (3), the acid solution is preferably hydrochloric acid and/or sulfuric acid; the concentration of the acid solution is 0.5-2mol/L; and/or
In step (3), the reaction conditions include: the temperature is 60-90 ℃, the time is more than 20min, and the liquid-solid ratio is 5-30:1mL/g.
Preferably, in step (4), the auxiliary source is selected from one or more of cerium source, iron source and copper source.
Preferably, in step (4), the catalyst is prepared as MnO 2 The addition amount of the manganese source is calculated as MnO 2 /(MnO 2 +carrier) x100% = 1-10 wt% based; and/or
The addition amount of the auxiliary source is calculated as the element and expressed as the auxiliary metal element/(MnO) 2 +carrier+promoter metal element) x100% = 0.5-2 wt% based on the total weight of the composition.
Preferably, in step (4), the rest time is 2 to 24 hours.
Preferably, in step (4), the firing conditions include: the temperature is 400-700 ℃ and the time is 3-6h.
In a second aspect, the invention provides a low temperature denitration catalyst prepared by the method described hereinbefore.
According to the invention, the titanium dioxide in the recovered waste denitration catalyst is regulated and controlled, and the titanium dioxide is applied to the denitration catalyst carrier to prepare the low-temperature denitration catalyst, so that the aim of recycling waste is achieved, on the one hand, the waste can be utilized on the other hand, the cost is greatly reduced, the method has a good application prospect, and meanwhile, the denitration catalyst (the titanium dioxide content is more than 85%) prepared by the method is applied to the low-temperature Duan Tuo denitration reaction, and the denitration activity can be more than 95% at 180 ℃.
Detailed Description
The following describes specific embodiments of the present invention in detail. It should be understood that the detailed description and specific examples, while indicating and illustrating the invention, are not intended to limit the invention.
The endpoints and any values of the ranges disclosed herein are not limited to the precise range or value, and are understood to encompass values approaching those ranges or values. For numerical ranges, one or more new numerical ranges may be found between the endpoints of each range, between the endpoint of each range and the individual point value, and between the individual point value, in combination with each other, and are to be considered as specifically disclosed herein.
The method for preparing the low-temperature denitration catalyst by utilizing the titanium-based waste denitration catalyst provided by the first aspect of the invention comprises the following steps of:
(1) Soaking the waste denitration catalyst in an acid solution, washing, drying, and then crushing;
(2) Placing the catalyst powder obtained in the step (1) into an alkali solution for reaction, and drying filter residues after solid-liquid separation;
(3) Placing filter residues in an acid solution for reaction, then taking an upper layer solid-liquid mixture for centrifugation, and drying to obtain a titanium slag carrier;
(4) Placing the titanium slag carrier in water, adding a manganese source and an auxiliary agent source, regulating the pH value of the solution to 9-10, standing, performing solid-liquid separation, drying the obtained solid, and roasting to obtain the low-temperature denitration catalyst.
In the method, the whole waste denitration catalyst is soaked in an acid solution, fly ash and metal impurities on the surface of the waste denitration catalyst are removed, then the waste denitration catalyst is crushed, catalyst powder is placed in an alkali solution, partial titanium, vanadium and tungsten in the catalyst powder react in the alkali solution and are dissolved in the solution, wherein titanium generates titanate, then the titanate reacts in an acid solution, the dissolved vanadium and tungsten respectively form vanadate and tungstic acid, the titanate is wrapped to form a suspended solid-liquid mixture, the lower layer is precipitated, the solid-liquid mixture on the upper layer is separated out and centrifuged (the lower layer is removed), and a titanium slag carrier is obtained after drying, and has good conveying performance and is convenient for dispersing active components better later, then a manganese source and an auxiliary agent source are added, the reaction is carried out in the alkali environment, and then the low-temperature denitration catalyst is obtained after roasting.
In the method of the invention, the waste denitration catalyst can be titanium-based denitration catalysts with various morphologies after long time passingThe denitration catalyst which is inactive after use. In a specific embodiment, the waste denitration catalyst contains 65 to 85 weight percent TiO 2 5-8 wt% SiO 2 WO 3-6 wt% 3 And 0.6 to 0.9 wt.% V 2 O 5 。
The waste denitration catalyst also needs to be purged to remove surface fly ash before being treated by adopting an acid solution.
In the method of the present invention, in a specific embodiment, in step (1), the acid solution may be various acid solutions common in the art, preferably a reducing acid solution. In particular embodiments, the reducing acid solution may be a citric acid solution and/or an oxalic acid solution.
In the method of the present invention, in order to remove impurities on the surface of the waste denitration catalyst cleanly while preventing the waste denitration catalyst from being dissolved, the concentration of the acid solution cannot be too high or too low. In particular embodiments, in step (1), the concentration of the acid solution may be 0.5-2mol/L, for example 0.5mol/L, 0.8mol/L, 1mol/L, 1.2mol/L, 1.5mol/L or 2mol/L. In the process of immersing the waste denitration catalyst in the acid solution, the solid ratio of the pickling solution is not particularly limited, as long as the waste denitration catalyst can be completely immersed and immersed for a proper time. In a specific embodiment, in step (1), the soaking time may be 20-60 minutes, for example 20 minutes, 30 minutes, 40 minutes, 50 minutes or 60 minutes.
In the method of the present invention, in order to make the elements in the waste denitration catalyst better participate in the subsequent reaction, it is necessary to pulverize the elements. In the step (1), the waste denitration catalyst after the impurity removal may be crushed to a particle size of less than 100 mesh, preferably 200 mesh or less.
In order to allow the titanium in the catalyst powder to be eluted in a proper form, while also partially eluting tungsten and vanadium, the catalyst powder is first treated with an alkali solution. The alkaline solution may be an alkaline solution well known to those skilled in the art, in particular, in step (2), the alkaline solution is a sodium hydroxide solution and/or a potassium hydroxide solution.
In order to form part of the titanium in the catalyst powder into titanate, such as sodium titanate and/or potassium titanate, and to dissolve part of the vanadium and tungsten in the catalyst powder at the same time, to recover the titanium slag carrier containing titanium, tungsten and vanadium, it is necessary to control the concentration of the alkali solution and the reaction conditions within proper ranges.
In particular embodiments, in step (2), the concentration of the alkaline solution may be from 5 to 40 wt%, preferably from 10 to 20 wt%, for example 10 wt%, 15 wt% or 20 wt%.
In a specific embodiment, in step (2), the temperature of the reaction may be 80-120 ℃, preferably 90-100 ℃, such as 90 ℃, 95 ℃ or 100 ℃.
In a specific embodiment, in step (2), the reaction time is > 0.5h, preferably 2-4h, e.g. 2h, 2.5h, 3h, 3.5h or 4h.
In particular embodiments, in step (2), the liquid to solid ratio of the reaction may be in the range of 5 to 30:1mL/g, preferably 8 to 20:1mL/g, for example 8:1mL/g, 10:1mL/g, 12:1mL/g, 14:1mL/g, 16:1mL/g, 18:1mL/g or 20:1mL/g.
In the method of the present invention, in order to form a solid-liquid mixture in suspension, the desired titanium slag and other solids are separated, and after treatment with an alkaline solution, treatment with an acidic solution is required.
In a specific embodiment, in step (3), the acid solution is an acid solution common in the art, preferably hydrochloric acid and/or sulfuric acid. In particular embodiments, the concentration of the acid solution may be 0.5-2mol/L, for example 0.5mol/L, 0.8mol/L, 1mol/L, 1.5mol/L, 1.8mol/L, or 2mol/L.
In particular embodiments, in step (3), the temperature of the reaction may be 60-90 ℃, such as 60 ℃, 65 ℃, 70 ℃, 75 ℃, 80 ℃, 85 ℃, or 90 ℃.
In a specific embodiment, in step (3), the reaction time is > 20min, preferably 30-60min, e.g. 30min, 35min, 40min, 45min, 50min, 55min or 60min.
In particular embodiments, in step (3), the liquid to solid ratio of the reaction may be in the range of 5-30:1mL/g, e.g., 5:1mL/g, 10:1mL/g, 15:1mL/g, 20:1mL/g, 25:1mL/g, or 30:1mL/g.
In the method of the invention, in order to improve the denitration activity of the prepared denitration catalyst, a certain auxiliary agent can be loaded in the denitration catalyst. In a specific embodiment, in the step (4), the auxiliary agent source is selected from one or more of a cerium source, an iron source and a copper source. The auxiliary source may be added in the form of an inorganic salt, preferably a nitrate, for example the cerium source may be added in the form of cerium nitrate. In the method of the present invention, the manganese source may be added in various forms well known to those skilled in the art, such as manganese nitrate.
In a specific embodiment, when the manganese source is added, the manganese source is added as MnO 2 Counting, firstly calculating added MnO 2 Then the amount of manganese nitrate to be added is converted according to the manganese element. In step (4), the reaction mixture is prepared with MnO 2 The addition amount of the manganese source is calculated as MnO 2 /(MnO 2 +support) x100% = 1-10 wt% based on the theoretical loading of Mn (in MnO 2 Calculated as) is 1 to 10 wt.%, preferably 3 to 8 wt.%, in particular, for example, 3 wt.%, 4 wt.%, 5 wt.%, 6 wt.%, 7 wt.%, or 8 wt.%.
In a specific embodiment, when the additive source is added, the additive source is added in an amount of additive metal element/(MnO) based on the metal element in the additive source 2 +carrier+adjuvant metal element) x100% = 0.5-2 wt%, calculated as theoretical loading of adjuvant is 0.5-2 wt%, specifically, for example, 0.5 wt%, 0.8 wt%, 1 wt%, 1.5 wt% or 2 wt%.
In a specific embodiment, in order to obtain the denitration catalyst precursor, after adding the manganese source and the auxiliary agent source, the solution needs to be left at an appropriate pH. In a specific embodiment, in step (4), the standing time is 2 to 24 hours.
In the method of the present invention, the calcination conditions may be selected as usual in the art. In a specific embodiment, in step (4), the firing temperature may be 400-700 ℃, such as 400 ℃, 450 ℃, 500 ℃, 550 ℃, 600 ℃, 650 ℃, or 700 ℃. In a specific embodiment, in step (4), the calcination time may be 3 to 6 hours, for example 3 hours, 3.5 hours, 4 hours, 4.5 hours, 5 hours, 5.5 hours or 6 hours.
In a second aspect, the invention provides a low temperature denitration catalyst prepared by the method described hereinbefore. The denitration activity of the low-temperature denitration catalyst can reach more than 95 percent at 180 ℃.
The present invention will be described in detail by way of examples, but the scope of the present invention is not limited thereto.
In the following examples and comparative examples, the terms MnO 2 /(MnO 2 +titanium slag carrier) x100% = 5 wt% the addition of the manganese source is calculated, i.e. the theoretical loading of Mn; according to Ce element/(MnO) 2 +titanium slag carrier+ce element) x100% =0.5 wt% the addition amount of the auxiliary source is calculated, that is, the theoretical loading amount of Ce.
Example 1
1) Taking a waste denitration catalyst of a coal-fired power plant of Jiangsu, and purging the waste denitration catalyst to remove surface fly ash;
2) Soaking the whole waste denitration catalyst in 0.5mol/L oxalic acid solution for 30min, washing with water, drying at 110 ℃ to constant weight, pulverizing the waste denitration catalyst to below 200 meshes, and measuring that the waste denitration catalyst contains 74.33% of TiO 2 7.22% SiO 2 WO 3.75% 3 And 0.87% of V 2 O 5 ；
3) Weighing 100g of crushed denitration catalyst powder, adding the powder into a sodium hydroxide solution with the concentration of 20 mass percent, and reacting for 3 hours at the temperature of 100 ℃ with the liquid-solid ratio of 10:1 mL/g; after the reaction is finished, filtering and drying filter residues;
4) The dried filter residues are reacted with 0.5mol/L hydrochloric acid, the liquid-solid ratio is 10:1mL/g, the reaction temperature is 80 ℃, the reaction time is 60min, the solid-liquid mixture which is not precipitated on the upper layer is taken after the reaction is completed, the catalyst titanium slag carrier is obtained after a plurality of times of centrifugation and drying, and the titanium slag carrier obtained by the method has good hydrophilicity, good conveying performance and is convenient for better dispersing active components;
5) Titanium slagThe carrier is put into deionized water, and manganese nitrate and cerium nitrate are added to ensure that the theoretical loading capacity of Mn (MnO 2 Calculated as 5 percent, the theoretical loading amount of Ce is 0.5 percent, then ammonia water is used for adjusting the pH value of the solution to 10, standing is carried out for 24 hours, centrifugal filtration is carried out, the filtered solid is dried to constant weight at 80 ℃, the dried product is roasted in a muffle furnace, the roasting temperature is 500 ℃, and the roasting time is 4 hours, thus obtaining the low-temperature denitration catalyst.
Example 2
1) Taking a waste denitration catalyst of a certain coal-fired power plant in Henan, and purging the waste denitration catalyst to remove surface fly ash;
2) Soaking the whole waste denitration catalyst in 0.5mol/L citric acid solution for 50min, washing with water, drying at 110deg.C to constant weight, pulverizing the waste denitration catalyst to below 200 mesh, and measuring that the waste denitration catalyst contains 77.17% TiO 2 5.16% SiO 2 WO 3.41% 3 And 0.66% V 2 O 5 ；
3) Weighing 100g of crushed denitration catalyst powder, adding the powder into 10 mass percent sodium hydroxide solution, and reacting for 2.5 hours at 80 ℃ with the liquid-solid ratio of 15:1 mL/g; after the reaction is completed, filtering and drying a filter cake;
4) The dried filter residues are reacted with 1mol/L sulfuric acid, the liquid-solid ratio is 30:1mL/g, the reaction temperature is 70 ℃, the reaction time is 50min, a solid-liquid mixture which is not precipitated on the upper layer is taken after the reaction is completed, and the catalyst titanium slag carrier is obtained after a plurality of times of centrifugation and drying, and the titanium slag carrier obtained by the method has good hydrophilicity, has good conveying performance and is convenient for better dispersing active components;
5) Putting titanium slag carrier into deionized water, adding manganese nitrate and cerium nitrate to make Mn theoretical load (MnO 2 Calculated as) is 5%, the Ce loading amount is 0.5%, then ammonia water is used for adjusting the pH value of the solution to 9, standing is carried out for 15h, centrifugal filtration is carried out, the filtered solid is dried to constant weight at 80 ℃, the dried product is roasted in a muffle furnace, the roasting temperature is 650 ℃, and the roasting time is 3.5h, thus obtaining the low-temperature denitration catalyst.
Example 3
1) Taking a waste denitration catalyst of a certain Ningxia coal-fired power plant, and purging the waste denitration catalyst to remove surface fly ash;
2) Soaking the whole waste denitration catalyst in 1mol/L oxalic acid solution for 40min, washing with water, drying at 110 ℃ to constant weight, pulverizing the waste denitration catalyst to below 200 meshes, and measuring that the waste denitration catalyst contains 80.38% of TiO 2 5.23% SiO 2 WO 3.05% 3 And 0.84% V 2 O 5 ；
3) Weighing 100g of crushed denitration catalyst powder, adding the powder into a 30 mass% sodium hydroxide solution, and reacting for 3 hours at 100 ℃ with a liquid-solid ratio of 20:1 mL/g; after the reaction is finished, filtering and drying filter residues;
4) The dried filter residues are reacted with 1.5mol/L hydrochloric acid, the liquid-solid ratio is 20:1mL/g, the reaction temperature is 65 ℃, the reaction time is 70min, the solid-liquid mixture which is not precipitated on the upper layer is taken after the reaction is completed, the solid-liquid mixture is centrifuged for multiple times, and the titanium slag carrier of the catalyst is obtained after the drying, and the titanium slag carrier obtained by the method has good hydrophilicity, good conveying performance and is convenient for better dispersing active components;
5) Putting titanium slag carrier into deionized water, adding manganese nitrate and cerium nitrate to make Mn theoretical load (MnO 2 Calculated as) is 5%, the theoretical loading amount of Ce is 0.5%, then ammonia water is used for adjusting the pH value of the solution to 9.5, standing is carried out for 24 hours, centrifugal filtration is carried out, the filtered solid is dried to constant weight at 80 ℃, the dried product is roasted in a muffle furnace, the roasting temperature is 450 ℃, and the roasting time is 4 hours, thus obtaining the low-temperature denitration catalyst.
Comparative example 1
The procedure of example 1 was followed, except that in step 4), the lower precipitate was taken after the completion of the reaction and dried to give a catalyst support.
Comparative example 2
The procedure of example 1 was followed except that the spent denitration catalyst was not purged and was not immersed in the oxalic acid solution.
Comparative example 3
The procedure of example 1 was followed, except that in step 5), the pH of the solution was adjusted to 7.5 with ammonia.
Comparative example 4
1) Taking a waste denitration catalyst of a coal-fired power plant of Jiangsu, and purging the waste denitration catalyst to remove surface fly ash;
2) Soaking the whole waste denitration catalyst in 0.5mol/L oxalic acid solution for 30min, washing with water, drying at 110 ℃ to constant weight, pulverizing the waste denitration catalyst to below 200 meshes, and measuring that the waste denitration catalyst contains 74.33% of TiO 2 7.22% SiO 2 WO 3.75% 3 And 0.87% of V 2 O 5 ；
3) Weighing 100g of crushed denitration catalyst powder, adding the powder into a 40 mass% sodium hydroxide solution, and reacting for 4 hours at 110 ℃ with a liquid-solid ratio of 10:1 mL/g; filtering and drying titanium slag after the reaction is completed;
4) Putting titanium slag into deionized water, adding manganese nitrate and cerium nitrate to enable the theoretical loading capacity of Mn (MnO 2 Calculated as 5 percent, the theoretical loading amount of Ce is 0.5 percent, then ammonia water is used for adjusting the pH value of the solution to 10, standing is carried out for 24 hours, centrifugal filtration is carried out, the filtered solid is dried to constant weight at 80 ℃, the dried product is roasted in a muffle furnace, the roasting temperature is 500 ℃, and the roasting time is 4 hours, thus obtaining the low-temperature denitration catalyst.
Test case
The titanium slag carriers obtained in examples 1 to 3 and comparative examples 1 to 4 were tested for water dispersibility and specific surface area, and the denitration catalysts obtained in examples 1 to 3 and comparative examples 1 to 4 were tested for denitration activity, specific surface area, manganese loading and Mn 4+ The proportion of the alloy is as follows, and the content of vanadium and tungsten is as follows. The results are shown in tables 1 and 2.
The water dispersibility test method comprises the following steps:
the degree of dispersion of the titanium dioxide particles is characterized by filtration of the titanium dioxide particles settling in an aqueous solution over a period of time. The faster the sedimentation speed, the poorer the dispersion effect;
specifically, 200g of a titanium slag carrier sample was weighed, 1L of water was added, and the mixture was stirred in a high-speed disperser at 2000R/MIN for 15 minutes, stirred for 15 minutes, and allowed to stand for 50 hours, whereby the dispersion effect (sedimentation height) of the solution was observed.
The specific surface area was measured using BET.
The method for testing the denitration activity comprises the following steps:
loading a small sample of the denitration catalyst and a small sample of the product into a catalyst performance evaluation reaction device, and introducing simulated gas to evaluate the activity of the denitration catalyst obtained in examples 1-3 and the product obtained in comparative examples 1-4. The simulated gas composition was similar to the industrial boiler tail gas composition, which was as follows: 500ppm NO, 400ppm NH 3 10% O 2 12% of water and the balance of nitrogen. Introducing the simulated gas into a denitration reactor for reaction, wherein the reaction temperature is 180 ℃, the concentration of nitrogen oxides in the flue gas before and after the reaction is analyzed by adopting a 42i-HL flue gas analyzer, and then the denitration rate of the denitration catalyst is calculated;
the concentration of nitrogen oxides in the flue gas before the reaction is a, the concentration of nitrogen oxides in the flue gas after the reaction is b, and the calculation formula of the denitration rate of the denitration catalyst is as follows:
η=(a-b)/a×100%。
the method for testing the manganese loading comprises the following steps:
measuring the content of Mn element by ICP-OES, and folding to obtain MnO 2 Is contained in the composition.
Mn 4+ The calculation method of the occupied proportion is as follows: XPS test is carried out on the sample, XPS peak separation is carried out on Mn, and bivalent Mn, trivalent Mn and tetravalent Mn are separated according to the binding energy, so that the respective peak areas are obtained, wherein the content of tetravalent Mn is the peak area of 4-valent Mn/(the peak area of bivalent Mn+the peak area of trivalent Mn+the peak area of tetravalent Mn) x100%.
The method for testing the vanadium content comprises the following steps:
measuring vanadium content by ICP-OES, and folding to obtain V 2 O 5 Is contained in the composition.
The method for testing the tungsten loading comprises the following steps:
measuring tungsten content by ICP-OES, and folding to obtain WO 3 Is contained in the composition.
The method for testing the content of titanium dioxide comprises the following steps:
measuring the content of titanium element by ICP-OES, and then folding to obtain TiO 2 Is contained in the composition.
TABLE 1 index of Carrier titanium slag
TABLE 2 denitration catalyst index
The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited thereto. Within the scope of the technical idea of the invention, a number of simple variants of the technical solution of the invention are possible, including combinations of the individual technical features in any other suitable way, which simple variants and combinations should likewise be regarded as being disclosed by the invention, all falling within the scope of protection of the invention.
Claims (13)
1. The method for preparing the low-temperature denitration catalyst by utilizing the titanium-based waste denitration catalyst is characterized by comprising the following steps of:
(1) Soaking the waste denitration catalyst in an acid solution, washing, drying, and then crushing;
(2) Placing the catalyst powder obtained in the step (1) into an alkali solution for reaction, and drying filter residues after solid-liquid separation;
(3) Placing filter residues in an acid solution for reaction, centrifuging an upper layer solid-liquid mixture, and drying to obtain a titanium slag carrier, wherein the concentration of the acid solution is 0.5-2mol/L; the reaction conditions include: the temperature is 60-90 ℃, the time is more than 20min, and the liquid-solid ratio is 5-30:1mL/g;
(4) Placing the titanium slag carrier in water, adding a manganese source and an auxiliary agent source, regulating the pH value of the solution to 9-10, standing, performing solid-liquid separation, drying the obtained solid, and roasting to obtain the low-temperature denitration catalyst.
2. The method according to claim 1, wherein in the step (1), the acid solution is a citric acid solution and/or an oxalic acid solution, and the concentration of the acid solution is 0.5-2mol/L.
3. The method of claim 1, wherein in step (1), the soaking time is 20-60 minutes.
4. A method according to claim 1 or 2, wherein in step (1) the particles are crushed to a particle size of less than 100 mesh.
5. The method according to claim 1, wherein in step (2), the alkali solution is a sodium hydroxide solution and/or a potassium hydroxide solution, and the concentration of the alkali solution is 5 to 40 wt%.
6. The method according to claim 1, wherein in step (2), the reaction conditions include: the temperature is 80-120 ℃, the time is more than 0.5h, and the liquid-solid ratio is 5-30:1mL/g.
7. The method according to claim 5 or 6, wherein in step (3), the acid solution is hydrochloric acid and/or sulfuric acid.
8. The method of claim 1, wherein in step (4), the promoter source is selected from one or more of a cerium source, an iron source, and a copper source.
9. The method of claim 7, wherein in step (4), the catalyst is prepared as MnO 2 The addition amount of the manganese source is calculated as MnO 2 /(MnO 2 +titanium slag carrier) x100% = 1-10 wt% based on the total weight of the alloy.
10. The method of claim 7, wherein in step (4), the auxiliary agent is calculated on an elemental basisThe addition amount of the source is expressed as the additive metal element/(MnO) 2 +titanium slag carrier+additive metal element) x100% = 0.5-2 wt% based on the total weight of the alloy.
11. The method according to claim 1, wherein in step (4), the standing time is 2 to 24 hours.
12. The method of claim 1, wherein in step (4), the firing conditions include: the temperature is 400-700 ℃ and the time is 3-6h.
13. A low temperature denitration catalyst prepared by the method of any one of claims 1 to 12.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310214589.4A CN115869940B (en) | 2023-03-08 | 2023-03-08 | Method for preparing low-temperature denitration catalyst by utilizing titanium-based waste denitration catalyst and low-temperature denitration catalyst |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310214589.4A CN115869940B (en) | 2023-03-08 | 2023-03-08 | Method for preparing low-temperature denitration catalyst by utilizing titanium-based waste denitration catalyst and low-temperature denitration catalyst |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115869940A CN115869940A (en) | 2023-03-31 |
| CN115869940B true CN115869940B (en) | 2023-05-05 |
Family
ID=85761983
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310214589.4A Active CN115869940B (en) | 2023-03-08 | 2023-03-08 | Method for preparing low-temperature denitration catalyst by utilizing titanium-based waste denitration catalyst and low-temperature denitration catalyst |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115869940B (en) |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6395665B2 (en) * | 1998-07-24 | 2002-05-28 | Mitsubishi Heavy Industries, Ltd. | Methods for the regeneration of a denitration catalyst |
| CN102240541B (en) * | 2011-05-23 | 2013-04-17 | 济南大学 | Amorphous composite oxide denitration catalyst and preparation method and use thereof |
| CN109750156B (en) * | 2019-03-15 | 2020-07-10 | 华北电力大学 | Method for recovering vanadium, tungsten/molybdenum and titanium elements from waste SCR denitration catalyst |
| CN115445604B (en) * | 2022-09-02 | 2023-11-10 | 国能龙源内蒙古环保有限公司 | Recycling recovery method of waste denitration catalyst |
| CN115487822A (en) * | 2022-10-18 | 2022-12-20 | 重庆科技学院 | Regeneration method of lead-poisoned Mn-Ce low-titanium blast furnace slag denitration catalyst |
-
2023
- 2023-03-08 CN CN202310214589.4A patent/CN115869940B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN115869940A (en) | 2023-03-31 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102114424A (en) | Low-temperature smoke denitration SCR (silicon controlled rectifier) catalyst and preparation method | |
| CN110724836B (en) | Method for extracting vanadium from waste SCR denitration catalyst by taking iron salt as roasting additive | |
| CN108816239B (en) | Supported catalyst, preparation method and application thereof | |
| CN112264034B (en) | Preparation method of low-temperature SCR denitration catalyst based on wolframite smelting slag | |
| CN103990496A (en) | Middle and low temperature SCR denitration catalyst with anti-poisoning performance, and preparation method thereof | |
| CN114058851A (en) | Method for recycling tungsten, molybdenum and titanium from waste denitration catalyst | |
| CN115869940B (en) | Method for preparing low-temperature denitration catalyst by utilizing titanium-based waste denitration catalyst and low-temperature denitration catalyst | |
| CN110605092B (en) | Iron-based rare earth oxygen storage type composite solid solution adsorbent and application thereof in flue gas dearsenification and demercuration | |
| CN107913695B (en) | Heavy metal deposition-resistant denitration catalyst and preparation method thereof | |
| CN108435159B (en) | Denitration catalyst for improving arsenic poisoning resistance and preparation method and application thereof | |
| CN116371429A (en) | Supported vanadate denitration catalyst and preparation method and application thereof | |
| CN113522316B (en) | Gas phase cerium-titanium sulfide supported tin oxide catalyst and preparation method and application thereof | |
| CN113528834A (en) | Method for recovering vanadium, tungsten and titanium from waste vanadium-titanium-based SCR catalyst | |
| CN115924967B (en) | Method for preparing titanium dioxide by using titanium slag and titanium dioxide | |
| CN110387471B (en) | Deep nickel removing method for waste catalytic cracking catalyst, silicon-aluminum material obtained by deep nickel removing method and application of silicon-aluminum material | |
| CN113070072B (en) | Catalyst for desulfurization and denitrification and preparation method thereof | |
| CN115869938B (en) | Treatment method of waste denitration catalyst, preparation method of denitration catalyst and application of denitration catalyst | |
| CN114733579B (en) | Method for recovering vanadium from waste denitration catalyst, catalyst regeneration agent and preparation method thereof, denitration catalyst and preparation method thereof | |
| CN107913696B (en) | Denitration catalyst capable of resisting sulfur dioxide oxidation and preparation method thereof | |
| CN112156816B (en) | Composite material and preparation method and application thereof | |
| CN115555002B (en) | Denitration catalyst and preparation method thereof | |
| CN115193446B (en) | Preparation method of catalyst for selectively catalyzing and removing NOx | |
| CN114682246B (en) | Titanium modified cerium vanadate catalyst and preparation method and application thereof | |
| CN110280264B (en) | Denitration catalyst and preparation method and application thereof | |
| CN113797981B (en) | Method for reactivating waste catalytic cracking catalyst |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |