Catalyst and Its Preparation Method and Use

Abstract

The present invention provides a catalyst, a preparation method thereof and a use thereof. The catalyst comprises: a catalyst carrier, and an active component, wherein the active component is loaded on the surface and / or inside of the catalyst carrier; wherein, based on the total mass of the catalyst, the content of the active component is 1 to 10%, and the content of the catalyst carrier is 90 to 99%. The catalyst of the present invention can achieve the synergistic removal of nitrogen oxides and carbon monoxide. The catalyst can realize the in-situ decoupling separation of the removal of nitrogen oxides and the oxidation of carbon monoxide, wherein the active component is used for removing nitrogen oxides, and the catalyst carrier is used for the oxidation of carbon monoxide.

Description

Technical Field

[0001] The present invention relates to a catalyst, a preparation method thereof, and uses thereof, belonging to the field of catalysts. Background Art

[0002] Nitrogen oxides (NO x ) are one of the main pollutants emitted from industrial flue gas, and are also important precursors for the formation of atmospheric pollutants such as haze and ozone; at the same time, China's energy structure mainly based on coal has also led to a large amount of carbon monoxide (CO) being emitted from industrial flue gas, and carbon monoxide has biological toxicity and persistence in the environment, causing great damage to human health and the ecological environment. Therefore, controlling the emissions of NO x and carbon monoxide in flue gas is a key task for improving air quality in China.

[0003] At present, ammonia selective catalytic reduction (NH3-SCR) denitrification is one of the most effective technologies for reducing NO x emissions from industrial flue gas. The core of this technology is the nitrogen oxide removal catalyst, and the most widely used SCR catalyst in industry is the V2O5-WO3 / TiO2 catalyst. The V2O5-WO3 / TiO2 catalyst can effectively control NO x emissions in the temperature window of 300-450°C. The catalytic oxidation method is the most effective technology for controlling carbon monoxide emissions, and the most widely used carbon monoxide oxidation catalyst in industry at present is the noble metal catalyst, such as Pt / CeO2 and Pt / TiO2, etc.

[0004] Using one reactor or one catalyst to simultaneously remove multiple pollutants is the most economical air pollution control technology. For NO x and carbon monoxide in flue gas, if an SCR reactor is used to simultaneously remove NO x and carbon monoxide in flue gas, it can reduce the floor area, catalyst, and energy consumption required for pollution control, and effectively reduce the cost of industrial flue gas pollutant control. However, the industrially used SCR catalyst V2O5-WO3 / TiO2 basically has no carbon monoxide oxidation activity within the working temperature window, and the industrially used carbon monoxide oxidation catalyst (noble metal catalyst) will preferentially oxidize the reducing agent NH3 to N2O and NO, showing extremely poor SCR activity. Therefore, developing an efficient catalyst is the key to realizing the synergy of flue gas denitrification and carbon monoxide oxidation.

[0005] The denitrification and co-oxidation of carbon monoxide catalyst must meet the following conditions: ① simultaneously having excellent SCR activity and carbon monoxide oxidation activity; ② the SCR reaction temperature window matches the carbon monoxide oxidation temperature window; ③ a certain stability against water and sulfur. However, currently, there is no report in the literature on a catalyst that can simultaneously meet these requirements.

[0006] Therefore, it has become an urgent technical problem to study a catalyst that can simultaneously denitrate and co-oxidize carbon monoxide. Summary of the Invention

[0007] Problems to be Solved by the Invention

[0008] In view of the technical problems existing in the prior art, the present invention first provides a catalyst. The catalyst of the present invention can achieve the co-removal of nitrogen oxides and carbon monoxide. The catalyst can achieve the in-situ decoupling separation of the removal of nitrogen oxides and the oxidation of carbon monoxide, wherein the active component is used for removing nitrogen oxides, and the catalyst carrier is used for the oxidation of carbon monoxide.

[0009] Furthermore, the present invention also provides a preparation method of the catalyst. The preparation method is simple and easy to implement, the raw materials are easy to obtain, and it is suitable for mass production.

[0010] Solutions for Solving the Problems

[0011] [1] A catalyst, which comprises:

[0012] A catalyst carrier, and

[0013] An active component, the active component being loaded on the surface and / or inside of the catalyst carrier; wherein, based on the total mass of the catalyst, the content of the active component is 1-10%, and the content of the catalyst carrier is 90-99%.

[0014] [2] The catalyst according to the above [1], wherein the catalyst carrier comprises a solid solution oxide containing tin atoms, titanium atoms, boron atoms, and optionally praseodymium atoms; preferably, based on 100% of the total molar amount of the catalyst, the molar amount of the tin atoms is 10%-50%, the molar amount of the titanium atoms is 10%-90%, the molar amount of the boron atoms is 1-10%, and the molar amount of the praseodymium atoms is 0-5%.

[0015] [3] The catalyst according to the above [2], wherein, in the catalyst carrier, the molar amount of the titanium atoms is greater than or equal to the sum of the molar amounts of the tin atoms, boron atoms, and optionally praseodymium atoms.

[0016] [4] The catalyst according to any one of the above [1]-[3], wherein the active component comprises cerium oxide, iron oxide, and optionally nickel oxide; preferably, based on 100% of the total mass of the catalyst, the content of the cerium oxide is 1-10%, the content of the iron oxide is 1-3%, and the content of the nickel oxide is 0-3%.

[0017] [5]. The catalyst according to [4] above, wherein, by mass, the content of the cerium oxide is greater than the content of the iron oxide.

[0018] [6]. A method for preparing the catalyst according to any one of [1]-[5] above, which includes the step of loading the active components on the surface and / or inside of the catalyst support.

[0019] [7]. The preparation method according to [6] above, wherein the preparation method includes the following steps:

[0020] Step 1): Prepare the catalyst support by the ice bath co-precipitation method;

[0021] Step 2): Load the active components on the surface and / or inside of the catalyst support by the impregnation method to obtain the catalyst.

[0022] [8]. The preparation method according to [7] above, wherein the preparation steps of the catalyst support include:

[0023] Under the condition of an ice water bath, mix the precursors of the catalyst support to obtain a precursor mixture;

[0024] Under the condition of an ice water bath, dissolve the precipitant in the first solvent to obtain a first solution;

[0025] Mix the precursor mixture and the first solution to obtain a precipitate;

[0026] Dry and calcine the precipitate to obtain the catalyst support.

[0027] [9]. The preparation method according to [7] or [8] above, wherein dissolve the precursor of the active component in the second solvent to obtain a second solution;

[0028] Place the catalyst support in the second solution and carry out condensation reflux under the condition of an oil bath to obtain an impregnated product;

[0029] Dry and calcine the impregnated product to obtain the catalyst support.

[0030]

[10] . Use of the catalyst according to any one of [1]-[5] above in synergistically removing nitrogen oxides and carbon monoxide from industrial flue gas.

[0031] Effects of the Invention

[0032] The catalyst of the present invention can achieve the synergistic removal of nitrogen oxides and carbon monoxide. The catalyst can realize the in-situ decoupling separation of the removal of nitrogen oxides and the oxidation of carbon monoxide, wherein the active components are used for removing nitrogen oxides, and the catalyst support is used for the oxidation of carbon monoxide.

[0033] The preparation method of the catalyst of the present invention is simple and easy to implement, and the raw materials are easy to obtain, which is suitable for mass production. Brief Description of the Drawings

[0034] Figure 1 Shows the catalyst support Sn of Example 2 0.48 Ti 0.5 B 0.01 Na 0.01 Pr 0.01 Schematic diagram of the O2 denitrification activity and carbon monoxide oxidation activity;

[0035] Figure 2 Shows the catalyst Ce of Example 2 0.05 Fe 0.01 / Sn 0.48 Ti 0.5 B 0.01 Na 0.01 Pr 0.01 Schematic diagram of the O2 denitrification activity and carbon monoxide oxidation activity;

[0036] Figure 3 Shows the catalyst Ce of Example 3 0.07 Fe 0.02 Ni 0.01 / Sn 0.4 Ti 0.6 B 0.02 Schematic diagram of the O2 denitrification activity and carbon monoxide oxidation activity;

[0037] Figure 4 Shows the X-ray diffraction patterns of the catalysts of Examples 4-6 of the present invention and TiO2. Detailed Description of the Invention

[0038] The following will detail various exemplary embodiments, features, and aspects of the present invention. The special word "exemplary" here means "serving as an example, embodiment, or illustration". Any embodiment described as "exemplary" here does not necessarily have to be interpreted as superior to or better than other embodiments.

[0039] In addition, to better illustrate the present invention, numerous specific details are given in the following detailed description. Those skilled in the art should understand that the present invention can still be implemented without some specific details. In other instances, methods, means, equipment, and steps well-known to those skilled in the art are not described in detail in order to highlight the gist of the present invention.

[0040] Unless otherwise stated, the units used in this specification are all international standard units, and the numerical values and numerical ranges appearing in the present invention should be understood to include the inevitable systematic errors in industrial production.

[0041] In this specification, the meaning expressed by "may" includes both the meaning of performing a certain process and the meaning of not performing a certain process.

[0042] In this specification, "some specific / preferred embodiments", "other specific / preferred embodiments", "embodiments", etc. mentioned refer to the specific elements related to the embodiment (for example, features, structures, properties, and / or characteristics) are included in at least one of the embodiments described herein, and may or may not exist in other embodiments. In addition, it should be understood that the elements can be combined in various embodiments in any suitable manner.

[0043] In this specification, the numerical range expressed by "numerical value A to numerical value B" refers to the range including the endpoint numerical values A and B.

[0044] In this specification, when "normal temperature" or "room temperature" is used, the temperature can be 10 - 40 °C.

[0045] <First aspect>

[0046] The first aspect of the present invention provides a catalyst, which comprises:

[0047] A catalyst carrier, and

[0048] An active component, which is loaded on the surface and / or inside of the catalyst carrier; wherein, based on the total mass of the catalyst, the content of the active component is 1 - 10%, for example: 2%, 4%, 6%, 8%, etc.; the content of the catalyst carrier is 90 - 99%, for example: 92%, 94%, 96%, 98%, etc. When the content of the active component is 1 - 10% and the content of the catalyst carrier is 90 - 99%, a denitrification rate of 80 - 95% and a CO oxidation activity of 70 - 95% can be achieved.

[0049] The catalyst of the present invention can achieve the synergistic removal of nitrogen oxides and carbon monoxide. Specifically, in the present invention, the catalyst can achieve the in-situ decoupling separation of the removal of nitrogen oxides and the oxidation of carbon monoxide, wherein the active component is mainly used for the removal of nitrogen oxides, while the catalyst carrier is mainly used for the oxidation of carbon monoxide.

[0050] Catalyst support

[0051] In the present invention, the catalyst carrier is mainly used for the oxidation of carbon monoxide.

[0052] In some specific embodiments, the catalyst support may include a solid solution oxide containing tin atoms, titanium atoms, boron atoms, and optionally present praseodymium atoms; when a solid solution oxide containing tin atoms, titanium atoms, boron atoms, and optionally present praseodymium atoms is used as the catalyst support, it can be used for carbon monoxide oxidation.

[0053] In the present invention, the catalyst support is a solid solution oxide containing tin atoms, titanium atoms, boron atoms, and optionally present praseodymium atoms, in which no segregation of tin dioxide-containing substances occurs. Moreover, after doping with atoms such as tin, titanium, boron, and optionally praseodymium, the catalyst support of the present invention can generate lattice defects, which is beneficial to activating oxygen molecules to generate active oxygen species, and these active oxygen species can oxidize carbon monoxide.

[0054] Preferably, based on 100% of the total molar amount of the catalyst, the molar amount of the tin atoms is 10% - 50%, for example: 15%, 20%, 25%, 30%, 35%, 40%, 45%, etc.; the molar amount of the titanium atoms is 10% - 90%, for example: 20%, 30%, 40%, 50%, 60%, 70%, 80%, etc.; the molar amount of the boron atoms is 1 - 10%, for example: 2%, 4%, 6%, 8%, etc.; the molar amount of the praseodymium atoms is 0 - 5%, for example: 1%, 2%, 3%, 4%, etc. When the molar amounts of the tin atoms, titanium atoms, boron atoms, and optionally present praseodymium atoms are within the above ranges, the denitration rate can reach 80 - 95%, and the oxidation activity of carbon monoxide can reach 70 - 95%.

[0055] In some specific embodiments, in the catalyst support, the molar amount of the titanium atoms is greater than or equal to the sum of the molar amounts of the tin atoms, boron atoms, and optionally present praseodymium atoms. In the catalyst support, due to the relatively high content of titanium atoms, the basic form of the formed solid solution oxide is rutile-phase titanium dioxide, specifically as Figure 4 shown.

[0056] Active component

[0057] In the catalyst support of the present invention, the active oxygen species generated by the catalyst support activating oxygen can oxidize carbon monoxide but have a relatively weak affinity for ammonia and nitrogen oxides, and have a poor reduction performance for nitrogen oxides. Therefore, the present invention uses an active component to remove nitrogen oxides. The active component of the present invention has a relatively poor affinity for carbon monoxide, and thus has a poor oxidation activity for carbon monoxide, but it does not affect the oxidation of carbon monoxide by the catalyst support.

[0058] In some specific embodiments, the active components include cerium oxide, iron oxide, and optionally nickel oxide; preferably, based on the total mass of the catalyst being 100%, the content of cerium oxide is 1-10%, for example: 2%, 4%, 6%, 8%, etc.; the content of iron oxide is 1-3%, for example: 1.5%, 2%, 2.5%, etc.; the content of nickel oxide is 0-3%, for example: 1%, 1.5%, 2%, 2.5%, etc. The active components of the present invention have excellent removal effects on nitrogen oxides.

[0059] Specifically, in the present invention, the cerium oxide may be cerium dioxide, the iron oxide is iron(III) oxide, and the nickel oxide is nickel oxide.

[0060] In some specific embodiments, by mass, the content of cerium oxide is greater than that of iron oxide. When the content of cerium oxide is greater than that of iron oxide, it is beneficial to improve the removal effect of nitrogen oxides in the synergistic control process.

[0061] Based on the reaction mechanisms of carbon monoxide catalytic oxidation and selective catalytic reduction, the present invention decouples and separates the carbon monoxide catalytic oxidation and selective catalytic reduction reactions on the catalyst support and the active components, reduces the mutual influence between the two catalytic reactions, and regulates the interaction between the support and the active components to construct a highly efficient catalyst for synergistic denitrification and carbon monoxide oxidation.

[0062] <Second aspect>

[0063] The second aspect of the present invention provides a preparation method of the catalyst according to the first aspect of the present invention, which includes the step of loading the active components on the surface and / or inside of the catalyst support. The preparation method of the present invention is simple and easy to implement, the raw materials are easy to obtain, and it is suitable for mass production.

[0064] In some specific embodiments, the preparation method includes the following steps:

[0065] Step 1) Prepare the catalyst support by the ice bath co-precipitation method;

[0066] Step 2) Load the active components on the surface and / or inside of the catalyst support by the impregnation method to obtain the catalyst.

[0067] Preparation of catalyst support

[0068] In the present invention, the preparation steps of the catalyst support may include:

[0069] Under the condition of an ice-water bath, mix the precursors of the catalyst support to obtain a precursor mixture;

[0070] Under the condition of an ice-water bath, a precipitant is dissolved in a first solvent to obtain a first solution;

[0071] The precursor mixture and the first solution are mixed to obtain a precipitate;

[0072] The precipitate is dried and then calcined to obtain a catalyst support.

[0073] In the present invention, under the condition of an ice-water bath, the precursors of the catalyst support are mixed to obtain a precursor mixture; specifically, the precursors of the catalyst support can be uniformly mixed by stirring or ultrasonic treatment. The present invention does not particularly limit the time of stirring or ultrasonic treatment, which can be selected according to the degree of mixing. Specifically, it can be 30 min or more.

[0074] For the precursors of the catalyst support, in the present invention, the precursors of the catalyst support include one or more combinations of soluble salts of metal elements. Specifically, the soluble salts can be one or more mixtures of their respective inorganic acid salts such as nitrates, sulfates, hydrochlorides, etc. or their hydrates, or one or more mixtures of organic acid salts such as acetates, oxalates, etc. or their hydrates.

[0075] In some specific embodiments, the precursors of the catalyst support include soluble salts of tin element, soluble salts of titanium element, soluble salts of boron element, and optionally soluble salts of praseodymium element.

[0076] Furthermore, in the present invention, the precursors of the catalyst support preferably include titanium tetrachloride, tin tetrachloride, ammonium borate, and optionally praseodymium nitrate. When the above four precursors are used for preparation, lattice defects can be generated, which is beneficial to activating oxygen molecules to produce active oxygen species, and the active oxygen species can oxidize carbon monoxide.

[0077] In some specific embodiments, based on the total molar amount of the precursors of the catalyst support being 100%, the molar amount of titanium tetrachloride is 10% - 90%, for example: 20%, 30%, 40%, 50%, 60%, 70%, 80%, etc.; the molar amount of tin tetrachloride is 10% - 50%, for example: 15%, 20%, 25%, 30%, 35%, 40%, 45%, etc.; the molar amount of ammonium borate is 1 - 10%, for example: 2%, 4%, 6%, 8%, etc.; the molar amount of praseodymium nitrate is 0 - 5%, for example: 1%, 2%, 3%, 4%, etc. When the content of each component of the precursors of the catalyst support is within the above range, the required catalyst support can be obtained.

[0078] Further, in the present invention, the molar content of titanium tetrachloride is greater than or equal to the sum of the molar contents of the three components of tin tetrachloride, ammonium borate, and praseodymium nitrate. When the molar content of titanium tetrachloride is relatively high, the basic form of the formed solid solution oxide is rutile-phase titanium dioxide.

[0079] Further, also under the condition of an ice-water bath, the precipitant is dissolved in the first solvent to obtain a first solution. This first solution is used to precipitate the precursor of the catalyst support.

[0080] Regarding the precipitant, the present invention is not particularly limited either, and it can be a commonly used precipitant in the art. Preferably, the precipitant can be ammonia water and / or ammonium carbonate.

[0081] Specifically, in the present invention, the ratio of the molar amount of the precipitant to the sum of the molar amounts of the precursor of the catalyst support is 3 to 6:1, for example: 3.5:1, 4:1, 4.5:1, 5:1, 5.5:1, etc.

[0082] Under the action of the precipitant, after mixing the precursor mixture and the first solution, a precipitate will be generated. Specifically, the precipitate can be generated by means of rapid stirring or ultrasonic waves. Then, the precipitate is obtained through solid-liquid separation. Regarding the method of solid-liquid separation, the present invention is not particularly limited and can be a commonly used method in the art, such as filtration, centrifugal separation, etc.

[0083] In addition, in the present invention, regarding the first solvent, the present invention is not particularly limited and can be a commonly used polar solvent in the art. Preferably, the first solvent can all be water.

[0084] After drying and calcining the precipitate, a catalyst support is obtained. Regarding the drying temperature and time, the present invention is not particularly limited. Generally, it can be at 60 to 120°C, for example: 70°C, 80°C, 90°C, 100°C, 110°C, etc.; the drying time is 6 to 24 hours, for example: 8 hours, 10 hours, 12 hours, 15 hours, 18 hours, 20 hours, etc.

[0085] In some specific embodiments, in order to obtain a catalyst support with excellent performance, the calcination is carried out at a heating rate of 1 to 5°C / min, for example: 2°C / min, 3°C / min, 4°C / min, etc., and the temperature is raised to a calcination temperature of 200 to 600°C, for example: 250°C, 300°C, 350°C, 400°C, 450°C, 500°C, 550°C, etc.; the calcination time is 2 to 6 h, for example: 2.5 h, 3 h, 3.5 h, 4 h, 4.5 h, 5 h, 5.5 h, etc. Further, in the present invention, the calcination can be carried out in an air atmosphere.

[0086] Further, in the present application, in order to obtain a catalyst support with a suitable lattice, the calcination can be carried out in stages. Specifically, the temperature can be raised at a rate of 1-5 °C / min to 200-349 °C for calcination for 1-3 h, and then further raised to 350 °C - 600 °C for calcination for 2-5 h. Preferably, in the present invention, the calcination can be carried out in an air atmosphere.

[0087] Loading of active component

[0088] In the present invention, the loading of the active component may include the following steps:

[0089] Dissolve the precursor of the active component in a second solvent to obtain a second solution;

[0090] Place the catalyst support in the second solution and carry out condensation reflux under oil bath conditions to obtain an impregnated product;

[0091] Dry and then calcine the impregnated product to obtain a catalyst support.

[0092] Specifically, dissolve the precursor of the active component in a second solvent to obtain a second solution; specifically, the precursor of the catalyst support can be dissolved by stirring or ultrasonic means. The present invention does not make a special limitation on the time of stirring or ultrasonic treatment, which can be selected according to the degree of mixing. Specifically, it can be more than 30 min.

[0093] For the precursor of the active component, in the present invention, the precursor of the active component includes one or a combination of two or more soluble salts of metal elements. Specifically, the soluble salts can be one or a mixture of two or more of their respective inorganic acid salts such as nitrates, sulfates, hydrochlorides, etc. or their hydrates, or can be one or a mixture of two or more of organic acid salts such as acetates, oxalates, etc. or their hydrates.

[0094] In some specific embodiments, the precursor of the active component includes a soluble salt of cerium element, a soluble salt of iron element, and an optional soluble salt of nickel element.

[0095] Further, in the present invention, the precursor of the active component preferably includes nitrate and / or chloride of cerium element, nitrate and / or chloride of iron element, and optionally nitrate and / or chloride of nickel element. By using nitrate and / or chloride, the active sites on the surface of the catalyst support for carbon monoxide oxidation will not be occupied.

[0096] The second solvent is the same as or different from the first solvent. Specifically, the present invention does not make a special limitation on the second solvent, which can be a commonly used polar solvent in the art. Preferably, the first solvent can all be water.

[0097] Furthermore, before impregnation, the second solution can be heated, which is beneficial to improving the dispersion of the active components. The present invention does not particularly limit the heating temperature, which can generally be 50-100 °C, for example: 60 °C, 70 °C, 80 °C, 90 °C, etc.

[0098] Furthermore, the catalyst support is placed in the second solution and condensed and refluxed under oil bath conditions to obtain an impregnated product. Condensing and refluxing under oil bath conditions is also beneficial to improving the dispersion of the active components.

[0099] For the oil bath temperature, it can be 80-120 °C, for example: 90 °C, 100 °C, 110 °C, etc.; for the oil bath time, it can be 1-5 hours, for example: 1.5 h, 2 h, 2.5 h, 3 h, 3.5 h, 4 h, 4.5 h, etc. During the oil bath, stirring can be appropriately carried out to make the impregnation more complete.

[0100] Finally, the impregnated product is dried and then calcined to obtain the catalyst. The present invention does not particularly limit the drying temperature and time, which can generally be at 60-120 °C, for example: 70 °C, 80 °C, 90 °C, 100 °C, 110 °C, etc.; the drying time is 6-24 hours, for example: 8 hours, 10 hours, 12 hours, 15 hours, 18 hours, 20 hours, etc.

[0101] In some specific embodiments, in order to obtain a catalyst with excellent performance, the calcination is carried out at a heating rate of 1-5 °C / min, for example: 2 °C / min, 3 °C / min, 4 °C / min, etc.; the temperature is raised to the calcination temperature of 200-600 °C, for example: 250 °C, 300 °C, 350 °C, 400 °C, 450 °C, 500 °C, 550 °C, etc.; the calcination time is 1-5 h, for example: 1.5 h, 2 h, 2.5 h, 3 h, 3.5 h, 4 h, 4.5 h, etc. Further, in the present invention, the calcination can be carried out in an air atmosphere.

[0102] <The third aspect>

[0103] The third aspect of the present invention provides a use of the catalyst according to the first aspect of the present invention for synergistically removing nitrogen oxides and carbon monoxide in industrial flue gas.

[0104] Examples

[0105] The following will describe the embodiments of the present invention in detail in conjunction with the examples. However, those skilled in the art will understand that the following examples are only used to illustrate the present invention and should not be regarded as limiting the scope of the present invention. Those not specified in the examples are carried out under conventional conditions or conditions recommended by the manufacturer. Those reagents or instruments not specified by the manufacturer can be obtained as conventional products through commercial purchase.

[0106] Example 1

[0107] Support Sn 0.48 Ti 0.5 B 0.01 Pr 0.01 Preparation of O2

[0108] Under the condition of an ice-water bath, titanium tetrachloride, tin tetrachloride, ammonium borate and praseodymium nitrate were mixed according to a molar ratio of 0.48:0.5:0.01:0.01 and stirred for half an hour to obtain a precursor mixture; then, under the condition of an ice-water bath, the precipitant ammonia water was dissolved in deionized water to form a second solution; under the condition of an ice-water bath, the above precursor mixture was gradually added to the second solution, and a precipitate was obtained by rapid stirring. After being washed thoroughly with deionized water and dried, it was calcined in an air atmosphere. The calcination procedure was as follows: heating to 250 °C at a heating rate of 2 °C / min and calcining for 2 h, and then continuing to heat to 500 °C and calcining for 3 h to obtain a catalyst support, denoted as: Sn 0.48 Ti 0.5 B 0.01 Pr 0.01 O2

[0109] Example 2

[0110] (1) Support Sn 0.48 Ti 0.5 B 0.01 Pr 0.01 Preparation of O2

[0111] Under the condition of an ice-water bath, titanium tetrachloride, tin tetrachloride, ammonium borate and praseodymium nitrate were mixed according to a molar ratio of 0.48:0.5:0.01:0.01 and stirred for half an hour to obtain a precursor mixture; then, under the condition of an ice-water bath, the precipitant ammonia water was dissolved in deionized water to form a second solution; under the condition of an ice-water bath, the above precursor mixture was gradually added to the second solution, and a precipitate was obtained by rapid stirring. After being washed thoroughly with deionized water and dried, it was calcined in an air atmosphere. The calcination procedure was as follows: heating to 250 °C at a heating rate of 2 °C / min and calcining for 2 h, and then continuing to heat to 450 °C and calcining for 3 h to obtain a catalyst support.

[0112] (2) Active component Ce 0.05 Fe 0.01 :

[0113] Dissolve cerium nitrate and iron nitrate in deionized water according to the loadings of 5% and 1% by mass respectively to obtain a second solution; heat the second solution to 80 °C; add the carrier prepared in step (1) above to the second solution, transfer the obtained mixed product to a distillation flask, carry out condensation reflux in an oil bath at 100 °C, stir for 3 hours and then filter to obtain an impregnated product; after drying the impregnated product, carry out calcination in an air atmosphere, wherein the calcination procedure is: raise the temperature to 400 °C at a heating rate of 2 °C / min and calcine for 3 h to obtain a catalyst, denoted as: Ce 0.05 Fe 0.01 / Sn 0.48 Ti 0.5 B 0.01 Pr 0.01 O2.

[0114] Use the DX-4000 infrared spectroscopic gas analyzer produced by GASMET Company of Finland to detect the ammonia oxidation rate. The ammonia oxidation rate of the obtained catalyst is about 36% at 400 °C, the test atmosphere is 500 ppm NH3 + 3% O2, and the space velocity is 20000 h -1 . The ratio of Lewis acid / (Lewis acid + Brønsted acid) is about 30%. The test method is the pyridine adsorption infrared experiment. Specifically, the catalyst is ground into powder and then pressed into tablets for testing. The test temperature is 150 °C; use a specific surface area analyzer of the catalyst to detect the specific surface area of the catalyst, and calculate the specific surface area of the catalyst according to the BET equation and the nitrogen adsorption and desorption curve. The specific surface area of the catalyst is about 60 m 2 / g.

[0115] Example 3

[0116] Support Sn 0.3 Ti 0.6 B 0.1 O2 preparation:

[0117] Under the condition of an ice-water bath, mix titanium tetrachloride, tin tetrachloride and ammonium borate in a molar ratio of 0.3:0.6:0.1, stir for half an hour to obtain a precursor mixture; then, under the condition of an ice-water bath, dissolve the precipitant ammonia water in deionized water to form a second solution; under the condition of an ice-water bath, gradually add the above precursor mixture to the second solution, stir rapidly to obtain a precipitate, wash it thoroughly with deionized water and dry it, and then carry out calcination in an air atmosphere, wherein the calcination procedure is: raise the temperature to 250 °C at a heating rate of 2 °C / min and calcine for 2 h, and then continue to raise the temperature to 500 °C and calcine for 3 h to obtain a catalyst support.

[0118] (2) Active component Ce 0.07 Fe 0.02 Ni 0.01

[0119] Dissolve cerium nitrate, iron nitrate, and nickel nitrate in deionized water according to loadings of 7%, 2%, and 1% by mass, respectively, to obtain a second solution; heat the second solution to 80 °C; add the carrier prepared in step (1) above to the second solution, transfer the resulting mixture to a distillation flask, carry out condensation reflux in an oil bath at 100 °C with stirring for 3 hours, then filter and dry, and perform calcination in an air atmosphere. The calcination procedure is as follows: raise the temperature to 450 °C at a heating rate of 2 °C / min and calcine for 3 h to obtain a catalyst, denoted as: Ce 0.07 Fe 0.02 Ni 0.01 / Sn 0.3 Ti 0.6 B 0.1 O2.

[0120] Use the DX-4000 infrared spectroscopic gas analyzer produced by GASMET Company of Finland to detect the ammonia oxidation rate. The ammonia oxidation rate of the obtained catalyst is about 50% at 400 °C, the test atmosphere is 500 ppm NH3 + 3% O2, and the space velocity is 20,000 h -1 . The ratio of Lewis acid / (Lewis acid + Bronsted acid) is about 40%. The test method is the pyridine adsorption infrared experiment. Specifically, the catalyst is ground into powder and then pressed into tablets for testing. The test temperature is 150 °C; use a specific surface area analyzer of the catalyst to detect the specific surface area of the catalyst, and calculate the specific surface area of the catalyst according to the BET equation and the nitrogen adsorption and desorption curve. The specific surface area of the catalyst is about 70 m 2 / g.

[0121] Example 4

[0122] Carrier Sn 0.49 Ti 0.5 B 0.01 Preparation of O2

[0123] Under ice-water bath conditions, mix titanium tetrachloride, tin tetrachloride, and ammonium borate in a molar ratio of 0.49:0.5:0.01, stir for half an hour to obtain a precursor mixture; then, under ice-water bath conditions, dissolve the precipitant ammonia water in deionized water to form a second solution; under ice-water bath conditions, gradually add the above precursor mixture to the second solution, stir rapidly to obtain a precipitate, wash it thoroughly with deionized water and dry it, and then perform calcination in an air atmosphere. The calcination procedure is as follows: raise the temperature to 250 °C at a heating rate of 2 °C / min and calcine for 2 h, and then continue to raise the temperature to 500 °C and calcine for 3 h to obtain a catalyst carrier, denoted as: Sn 0.49 Ti 0.5 B 0.01 O2.

[0124] Example 5

[0125] Carrier Sn0.2 Ti 0.75 B 0.05 Preparation of O2

[0126] Under the condition of an ice - water bath, titanium tetrachloride, tin tetrachloride and ammonium borate were mixed according to a molar ratio of 0.2:0.75:0.05 and stirred for half an hour to obtain a precursor mixture; then, under the condition of an ice - water bath, the precipitant ammonia water was dissolved in deionized water to form a second solution; under the condition of an ice - water bath, the above - mentioned precursor mixture was gradually added to the second solution, and a precipitate was obtained by rapid stirring. After being washed thoroughly with deionized water and dried, it was calcined in an air atmosphere. The calcination procedure was as follows: heated to 250 °C at a heating rate of 2 °C / min and calcined for 2 h, then continued to be heated to 500 °C and calcined for 3 h to obtain a catalyst support, denoted as: Sn 0.2 Ti 0.75 B 0.05 O2.

[0127] Example 6

[0128] Support Sn 0.1 Ti 0.89 B 0.01 Preparation of O2

[0129] Under the condition of an ice - water bath, titanium tetrachloride, tin tetrachloride and ammonium borate were mixed according to a molar ratio of 0.1:0.89:0.01 and stirred for half an hour to obtain a precursor mixture; then, under the condition of an ice - water bath, the precipitant ammonia water was dissolved in deionized water to form a second solution; under the condition of an ice - water bath, the above - mentioned precursor mixture was gradually added to the second solution, and a precipitate was obtained by rapid stirring. After being washed thoroughly with deionized water and dried, it was calcined in an air atmosphere. The calcination procedure was as follows: heated to 250 °C at a heating rate of 2 °C / min and calcined for 2 h, then continued to be heated to 500 °C and calcined for 3 h to obtain a catalyst support, denoted as: Sn 0.1 Ti 0.89 B 0.01 O2.

[0130] Using the catalyst supports of Examples 4 - 6, when analyzing by powder X - ray diffraction method with CuK α radiation experimental conditions, the 2θ(°) of the diffraction peak and the intensity of the diffraction peak are as Figure 4 shown. It can be seen from Figure 4 that in the catalyst support of the present application, due to the relatively high content of titanium atoms, the basic form of the formed solid - solution oxide is rutile - phase titanium dioxide.

[0131] Performance test

[0132] The catalyst support of Example 1 and the catalysts of Examples 2-3 were tested for denitrification and carbon monoxide oxidation activity. Among them, the test conditions were as follows: carbon monoxide concentration of 1000 ppm, nitrogen oxide concentration of 500 ppm, ammonia concentration of 500 ppm, and oxygen concentration of 5%. During the test, the operating temperature was 270-420 °C, and the space velocity was 60000 h -1 , and the results are as Figures 1-3 shown.

[0133] It can be seen from Figure 1 that the carbon monoxide oxidation activity of the catalyst support Sn 0.48 Ti 0.5 B 0.01 Pr 0.01 O2 of Example 1 was greater than 90%, but the denitrification activity was only 10-35%. It can be seen from Figure 2 that the carbon monoxide oxidation activity of the catalyst Ce 0.05 Fe 0.01 / Sn 0.48 Ti 0.5 B 0.01 Pr 0.01 O2 of Example 2 was greater than 90%, and the denitrification activity was also greater than 95%.

[0134] The catalyst Ce 0.05 Fe 0.01 / Sn 0.48 Ti 0.5 B 0.01 Pr 0.01 O2 of Example 2 and the catalyst support Sn 0.48 Ti 0.5 B 0.01 Pr 0.01 O2 of Example 1 had little difference in carbon monoxide oxidation activity, but the denitrification activity increased significantly. This is due to the use of the active component for denitrification.

[0135] It can be seen from Figure 3 that the carbon monoxide oxidation activity of the catalyst Ce 0.07 Fe 0.02 Ni 0.01 / Sn 0.3 Ti 0.6 B 0.1 O2 of Example 3 was greater than 90%, and the denitrification activity was also greater than 95%.

[0136] Pilot experiment

[0137] In the pilot-scale test conducted in a coal-fired power plant, the flue gas volume was 6000 m 3 / h, and the inlet flue gas temperature was about 320 °C. The pilot-scale test used the Ce of Example 2 prepared by integral extrusion molding.0.05 Fe 0.01 / Sn 0.48 Ti 0.5 B 0.01 Pr 0.01 O2 catalyst, with an airspeed of 5000 h -1 , and the pilot run time was 30 days. During the pilot run, an infrared gas analyzer DX-4000 produced by Finnish company GASMET was used to continuously detect NO, NO2, CO, CO2, SO2 and H2O in the inlet and outlet flue gases online. The stable effect after the pilot run is shown in Table 1.

[0138] Table 1 Stable effect of the catalyst in Example 2 during pilot run

[0139] Serial number Name Unit Inlet Outlet 1h average value Efficiency 1 <![CDATA[NO x > <![CDATA[mg / Nm 3 > ～300 12.5 95％ 2 CO <![CDATA[mg / Nm 3 > ～1100 55 90.1％ 3 <![CDATA[SO2]]> <![CDATA[mg / Nm 3 > ～200 165 17.5％ 4 <![CDATA[H2O]]> ％ 8.3 8.1 -

[0140] As can be seen from Table 1, the denitrification and carbon monoxide oxidation catalyst of the present invention has excellent denitrification and carbon monoxide oxidation performance, and can provide an effective strategy for the synergistic removal of nitrogen oxides and carbon monoxide in industrial flue gas.

[0141] It should be noted that although the technical solutions of the present invention are introduced by specific examples, those skilled in the art can understand that the present invention should not be limited thereto.

[0142] The embodiments of the present invention have been described above. The above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations are obvious to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The choice of terms used herein is intended to best explain the principles of the embodiments, practical applications, or improvements to technologies in the market, or to enable other ordinary skilled persons in the art to understand the embodiments disclosed herein.

Claims

1. A catalyst, characterized in that, The catalyst includes: a catalyst support, and an active component, which is loaded on the surface and / or inside of the catalyst support; wherein, based on the total mass of the catalyst, the content of the active component is 1-10%, and the content of the catalyst support is 90-99%; the catalyst support includes a solid solution oxide containing tin atoms, titanium atoms, boron atoms and optionally present praseodymium atoms, the molar amount of the titanium atoms is greater than or equal to the sum of the molar amounts of the tin atoms, boron atoms and optionally present praseodymium atoms, and the basic form of titanium dioxide in the solid solution oxide is rutile phase titanium dioxide; the active component includes cerium oxide, iron oxide and optionally present nickel oxide, and the content of the cerium oxide is greater than the content of the iron oxide; Based on the total molar amount of the catalyst being 100%, the molar amount of the tin atoms is 10%-50%, the molar amount of the titanium atoms is 10%-80%, the molar amount of the boron atoms is 1-10%, and the molar amount of the praseodymium atoms is 0-5%.

2. The catalyst according to claim 1, characterized in that, Based on the total mass of the catalyst being 100%, the content of the cerium oxide is 1-8%, the content of the iron oxide is 1-3%, and the content of the nickel oxide is 0-3%.

3. A method for preparing the catalyst according to claim 1 or 2, characterized in that: It includes the step of loading the active component on the surface and / or inside of the catalyst support.

4. The preparation method according to claim 3, characterized in that, The preparation method includes the following steps: Step 1) Prepare the catalyst support by the ice bath co-precipitation method; Step 2) Load the active component on the surface and / or inside of the catalyst support by the impregnation method to obtain the catalyst.

5. The preparation method according to claim 4, characterized in that, The preparation steps of the catalyst support include: Under the condition of an ice water bath, mix the precursors of the catalyst support to obtain a precursor mixture; Under the condition of an ice water bath, dissolve the precipitant in the first solvent to obtain a first solution; Mix the precursor mixture and the first solution to obtain a precipitate; Dry and calcine the precipitate to obtain the catalyst support.

6. The preparation method according to claim 4 or 5, characterized in that, Dissolve the precursor of the active component in the second solvent to obtain a second solution; Place the catalyst support in the second solution and carry out condensation reflux under the condition of an oil bath to obtain an impregnated product; Dry and calcine the impregnated product to obtain the catalyst.

7. Use of the catalyst according to claim 1 or 2 for synergistically removing nitrogen oxides and carbon monoxide from industrial flue gas.

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