Preparation method and application of a denitrification and mercury co-removal SCR honeycomb catalyst

Abstract

The present invention discloses a preparation method and application of a denitrification and mercury co-removal SCR honeycomb catalyst, which relates to the technical field of flue gas denitrification. The raw material components of the denitrification catalyst of the present invention include: anatase catalytic titanium dioxide, pseudo-boehmite, ammonium metavanadate-monoethanolamine aqueous solution, ammonium heptamolybdate, ammonium metatungstate, glass fiber, cerium nitrate, copper nitrate, antimony acetate, silica sol, sesbania powder and polyethylene oxide. The denitrification and mercury co-removal SCR catalyst prepared by the present invention has a large specific surface area, good dispersion of active components, strong mercury adsorption and oxidation ability, remarkable denitrification effect, and has a good Hg<supgt;0< / supgt; oxidation rate, and is very suitable for the denitrification and mercury emission control of fixed-source flue gas such as thermal power plants, coking plants, waste incinerators, iron and steel sintering machines, and cement kilns.

Description

Technical Field

[0001] The present invention relates to the technical field of flue gas denitrification, and in particular to a preparation method and application of a denitrification and mercury co-removal SCR honeycomb catalyst. Background Art

[0002] NOx in the atmosphere mainly comes from the combustion of fossil fuels. The NOx generated by combustion has the characteristics of high emission concentration and concentrated emission locations. Therefore, it is difficult to participate in the nitrogen cycle process, resulting in environmental pollution. At the same time, mercury is also one of the most volatile trace elements in coal, and mercury can seriously endanger life health and the ecological environment. Therefore, the treatment of nitrogen oxides and mercury pollutants in flue gas is an urgent problem to be solved in the sustainable development process of current industrial production.

[0003] Due to the volatility, persistence and bioaccumulation of mercury in the environment, mercury emissions have attracted wide attention in recent years. Coal-fired power plants are the main anthropogenic sources of mercury pollutant emissions. Mercury in coal-fired flue gas mainly exists in the following three forms: elemental mercury (Hg 0 ), oxidized mercury (Hg 2+ ), and particulate-bound mercury (Hg p ). Among them, Hg 0 is difficult to be captured by existing air pollution control devices (APCDs), while Hg 2+ and Hg p can be easily removed through a wet flue gas desulfurization (WFGD) system and an electrostatic precipitator. Therefore, oxidizing Hg 0 to Hg 2+ and removing it is of great significance for improving the mercury removal rate.

[0004] Nitrogen oxides (NOx) are a kind of air pollutants and have a significant impact on acid rain and urban photochemical smog. Selective catalytic reduction (SCR) denitrification systems are widely used in coal-fired power plants around the world to control NOx emissions due to their high efficiency and economic feasibility. Nowadays, the most widely used commercial SCR catalyst is the V2O5 / TiO2-based catalyst, using tungsten trioxide (WO3) or molybdenum trioxide (MoO3) as a promoter to improve the stability and SO2 resistance of the catalyst. However, the existing SCR catalysts have very limited oxidation ability for elemental mercury in flue gas. Therefore, providing an SCR catalyst for denitrification and mercury co-removal is an urgent technical problem to be solved. Summary of the Invention

[0005] The purpose of the present invention is to provide a preparation method and application of a denitrification and mercury co-removal SCR honeycomb catalyst to solve the problems existing in the above-mentioned prior art and synchronously achieve high-efficiency denitrification and mercury removal of flue gas.

[0006] To achieve the above purpose, the present invention provides the following solutions:

[0007] One of the technical solutions of the present invention is to provide a denitrification and mercury co-removal SCR honeycomb catalyst, which comprises the following raw material components in parts by mass:

[0008] 63.5-65 parts of anatase catalytic titanium dioxide, 1.0-1.2 parts of pseudoboehmite, 11-13 parts of ammonium metavanadate-monoethanolamine aqueous solution, 2.0-2.3 parts of ammonium heptamolybdate, 1.3-1.6 parts of ammonium metatungstate, 5-5.5 parts of glass fiber, 1.1-1.5 parts of cerium nitrate, 1.9-2.2 parts of copper nitrate, 1.3-1.6 parts of antimony acetate, 1.5-2.5 parts of silica sol, 0.4-0.8 parts of lactic acid, 0.5-1 part of sesbania powder and 0.5-1 part of polyoxyethylene.

[0009] The anatase titanium dioxide mainly contains TiO2 component, with a specific surface area of 100-110 m 2 / g, and the particle size distribution D50 ranges from 0.8 to 1.2 μm. It mainly plays the role of the catalyst substrate, provides a carrier for the uniform distribution of the catalyst active components, and improves the N2 selectivity.

[0010] Pseudoboehmite, with the main component of Al2O3·nH2O (n = 0.08-0.62), mainly functions to improve the compressive strength of the catalyst.

[0011] The ammonium metavanadate-monoethanolamine aqueous solution is a homogeneous solution obtained by stirring and mixing ammonium metavanadate, monoethanolamine and water in a mass ratio of 1:1:3 at 75 °C ± 5 °C; monoethanolamine is a co-solvent for ammonium metavanadate. Ammonium metavanadate is the precursor of the denitrification reaction active component V2O5, which is converted into V2O5 after calcination to provide active sites for the denitrification reaction.

[0012] The silica sol is a 25 wt.% silica sol, which is used in combination with pseudoboehmite to improve the mechanical strength of the catalyst.

[0013] Antimony acetate, the main function of which is to improve the anti-SO2 performance of the catalyst and reduce the SO2 / SO3 conversion rate;

[0014] Cerium nitrate, the main function of which is to increase the acid amount of the catalyst and improve the denitrification performance of the catalyst at high temperature;

[0015] Copper nitrate, the main function of which is to improve the oxidation performance of the catalyst and enhance the oxidation ability of the catalyst for Hg 0 of.

[0016] The main components of the glass fiber are SiO2, Al2O3, and CaO, which play a framework role in the catalyst and improve the structural strength of the catalyst.

[0017] Lactic acid adjusts the pH value of the catalyst mud and mainly improves the plasticity of the material.

[0018] Sesbania powder, with a viscosity range of 850 - 950 mPa·s, is a pore-forming agent, mainly improving the water absorption and water retention of the mud, and improving the plasticity of the mud.

[0019] Polyethylene oxide (PEO), with a viscosity range of 250 - 350 mPa·s, comprehensively exerts the functions of a thickening agent, a flocculant and a lubricant, and improves the plasticity of the mud.

[0020] Ammonium heptamolybdate and ammonium metatungstate are catalyst activity promoters, used to improve the anti-sintering ability of the catalyst, enhance the thermal stability of the catalyst, and improve the resistance of the catalyst to arsenic and alkali metal poisoning.

[0021] As a further preference of the present invention, the raw material components of the above-mentioned denitrification and mercury co-removal SCR honeycomb catalyst further include 3.5 - 5 parts by mass of ammonia water.

[0022] The second technical solution of the present invention is to provide a preparation method of the above-mentioned denitrification and mercury co-removal SCR honeycomb catalyst, including the following steps:

[0023] (1) Mix anatase titanium dioxide, silica sol, pseudo-boehmite and water so that the water content of the system is 38% - 39%, and stir and mix at 60 - 80 °C to obtain a mixture A;

[0024] (2) Add ammonium metatungstate, cerium nitrate, copper nitrate and antimony acetate to the obtained mixture A and mix to obtain a mixture B;

[0025] (3) Adjust the pH value of the mixture B to 8.2 - 8.5, then add ammonium heptamolybdate and ammonium metavanadate - monoethanolamine aqueous solution, and control the water content of the system to be 33% - 34% to obtain a mixture C;

[0026] (4) After heating and stirring the mixture C to adjust the water content of the system to 30 - 31%, adjust the pH value to 7.6 - 8.0, then add glass fiber and mix and stir, then add sesbania powder and polyethylene oxide, control the water content of the system to be 26 - 29%, then carry out aging treatment, and extrude the aged mud through a professional extrusion die to obtain honeycomb catalyst monomers, and then through drying and calcination treatment, to obtain the denitrification and mercury co-removal SCR honeycomb catalyst.

[0027] The third technical solution of the present invention is to provide another preparation method of the denitrification and mercury co-removal SCR honeycomb catalyst, including the following steps:

[0028] (1) Mix anatase titanium dioxide, silica sol, pseudo-boehmite and water so that the water content of the system is 38% - 39%, and stir and mix at 60 - 80 °C to obtain a mixture A;

[0029] (2) Add ammonium metatungstate, cerium nitrate, copper nitrate and antimony acetate to the obtained mixture A, and mix them to obtain mixture B;

[0030] (3) Add ammonia water to make the pH value of mixture B be 8.2 - 8.5, then add ammonium heptamolybdate and ammonium metavanadate - monoethanolamine aqueous solution, and adjust the water content of the system to 33% - 34% to obtain mixture C;

[0031] (4) Heat and stir mixture C, after adjusting the water content of the system to 30 - 31%, add lactic acid to adjust the pH value to 7.6 - 8.0, then add glass fiber and mix and stir, then add sesbania powder and polyethylene oxide, adjust the water content of the system to 26 - 29%, then carry out aging treatment, extrude the obtained aged mud through a professional extrusion die to obtain honeycomb catalyst monomers, and then carry out drying and calcination treatment to obtain the denitrification and mercury - synergistic removal SCR honeycomb catalyst.

[0032] A further preferred preparation process of the present invention is as follows:

[0033] (1) Add anatase titanium dioxide, silica sol and pseudo - boehmite to a kneader and knead them evenly, then add deionized water until the water content is 38% - 39%, and mix and stir the obtained slurry - like mixture evenly at 60 - 80 °C to obtain mixture A;

[0034] (2) Add ammonium metatungstate, cerium nitrate, copper nitrate and antimony acetate to mixture A and mix them evenly to obtain mixture B;

[0035] (3) Add ammonia water to the obtained mixture B to adjust the pH value of the reaction system to 8.2 - 8.5, then add ammonium heptamolybdate and mix evenly, then add ammonium metavanadate - monoethanolamine aqueous solution, stir for 60 min, then heat up and remove moisture until the water content of the mud in the kneader is 33% - 34% to obtain mixture C;

[0036] (4) Heat and stir mixture C, after adjusting the water content of the system to 30 - 31%, add lactic acid to adjust the pH to 7.6 - 8.0, add glass fiber to the obtained mixture C, knead for 40 - 60 min, then adjust the water content of the mud to 30 - 31%, then add sesbania powder and polyethylene oxide, continue to stir and adjust the water content of the mixed material to 28%, and the pH value to 7.6 - 8.0, then continue to stand and age in the kneader for 8 - 12 h to obtain aged mud D.

[0037] (5) Extrude the aged mud D into strip - shaped mud through a pre - extruder, remove impurities in the mud, and extrude honeycomb catalyst monomers with an extrusion die (11 - 30 holes).

[0038] (6) Calcinate the extruded honeycomb catalyst monomers after two - stage drying, the calcination temperature is 500 °C, and the calcination time is 35 h.

[0039] As a further preference of the present invention, the two-stage drying of the present invention is specifically as follows:

[0040] The temperature of the first-stage drying is 30°C - 60°C, the humidity is 80 - 10%, and the drying time is 8 days, which are in turn high humidity and low temperature (humidity 80% - 60%, temperature 30°C - 40°C), medium humidity and medium temperature (humidity 60% - 20%, temperature 40°C - 50°C), low humidity and high temperature (humidity 20% - 10%, temperature 50°C - 60°C); the temperature of the second-stage drying is 60°C, and the time is 24h.

[0041] The fourth technical solution of the present invention is to provide the application of the above denitrification and mercury co-removal SCR honeycomb catalyst in flue gas denitrification and / or mercury removal.

[0042] The content range of the main components in the catalyst of the present invention is as follows: TiO2: 79 - 86%; V2O5: 2.2 - 2.7%; WO3: 1.4 - 1.8%; MoO3: 2.0 - 2.3%; CeO2: 0.8 - 1.2%; CuO: 0.7 - 0.8%; Sb2O3: 0.7 - 0.9%; SiO2: 3.7 - 5.5%; Al2O3: 1.2 - 1.5%; CaO%: 1.5 - 2.5%.

[0043] The present invention adopts a kneading and extrusion molding process to prepare a denitrification and mercury co-removal SCR catalyst by Ce, Cu, and Sb modification and doping, which increases the interaction between the active components and the carrier, and increases the chemisorbed oxygen O β of the catalyst, forming a catalyst with a large specific surface area, good dispersion of active components, and strong mercury adsorption and oxidation ability, reducing the adsorption performance of the catalyst for SO2, and overcoming the problems of low oxidation efficiency, poor stability, and high SO2 / SO3 conversion rate of traditional SCR denitrification and mercury removal catalysts.

[0044] The present invention provides a CeO2 / CuO / Sb2O3 modified vanadium-titanium-based honeycomb catalyst structure system, which introduces an appropriate proportion of SiO2 and Al2O3, improving the mechanical compressive strength of the catalyst (radial compressive strength > 0.85 MPa, axial compressive strength > 3.20 MPa). Compared with the traditional vanadium-titanium honeycomb catalyst, the catalyst prepared by the present invention has higher denitrification and Hg oxidation performance.

[0045] The denitrification and mercury removal principle of the catalyst of the present invention is as follows: Gaseous Hg in the flue gas 0 (Hg g 0 ) is first adsorbed on the catalyst surface to form adsorbed Hg 0 (Hg 0 ad ). The redox reaction existing on the catalyst surface Generates a large amount of chemisorbed oxygen, and the adsorbed Hg 0 reacts with the abundant chemisorbed oxygen on the catalyst surface to form adsorbed HgO (HgO ad ). The consumed chemisorbed oxygen can be replenished to the oxygen vacancies on the catalyst surface through gaseous O2 in the flue gas and thus regenerated, achieving the efficient oxidation of Hg 0 . After the HgO adsorbed on the catalyst surface reaches adsorption saturation, it will be released into the flue gas, thus ensuring that the catalyst can efficiently oxidize Hg 0 for a long time.

[0046] The denitrification and mercury co-removal SCR catalyst prepared by the present invention is applicable to a flue gas temperature of 200 - 380 °C, an air velocity of 3000 / h - 5000 / h, a NOx concentration in the flue gas of 300 - 650 mg / Nm 3 , an O2 content of 4 - 16% (volume fraction), a SO2 concentration of 300 - 500 mg / Nm 3 , a Hg content of 300 - 600 ng / m 3 . When the ammonia-nitrogen molar ratio is 1, a denitrification efficiency of over 90% can be achieved. Meanwhile, the mercury oxidation rate also reaches over 90%.

[0047] The present invention discloses the following technical effects:

[0048] The denitrification and mercury co-removal SCR catalyst prepared by the present invention has a large specific surface area, good dispersion of active components, strong mercury adsorption and oxidation ability, significant denitrification effect, and a good Hg 0 oxidation rate, and is applicable to the denitrification and mercury emission control of fixed-source flue gases such as thermal power plants, coking plants, waste incinerators, iron and steel sintering machines, and cement kilns. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0050] Figure 1 Shows the oxidation rate of elemental Hg in the flue gas by the catalysts prepared in Examples 1 - 4 and Comparative Examples 1 - 2 of the present invention.

[0051] Figure 2 Shows the denitrification efficiency of the catalysts prepared in Examples 1 - 4 and Comparative Examples 1 - 2 of the present invention;

[0052] Figure 3 Shows a physical diagram of the denitrification and mercury co-removal SCR honeycomb catalyst prepared in Example 1 of the present invention. Detailed Embodiments

[0053] The various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation on the present invention, but rather as a more detailed description of certain aspects, features, and implementation schemes of the present invention.

[0054] It should be understood that the terms used in the present invention are only for describing specific embodiments and are not used to limit the present invention. Additionally, for the numerical ranges in the present invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any intermediate value within any stated value or stated range, as well as each smaller range between any other stated value or intermediate value within the stated range, is also included in the present invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0055] Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the present invention pertains. Although the present invention only describes preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials related to the documents. In case of conflict with any incorporated document, the content of this specification shall prevail.

[0056] Without departing from the scope or spirit of the present invention, various improvements and changes can be made to the specific embodiments of the present invention specification, which are obvious to those skilled in the art. Other embodiments obtained from the specification of the present invention are obvious to those skilled in the art. The specification and embodiments of the present invention are merely exemplary.

[0057] Regarding the use of "comprising", "including", "having", "containing", etc. herein, they are all open-ended terms, meaning including but not limited to.

[0058] The types and mass ratios of the raw materials of the SCR honeycomb catalyst for simultaneous denitrification and mercury removal in the embodiments of the present invention are shown in Table 1 as follows:

[0059] Table 1

[0060] Name Parts by mass Name Parts by mass Anatase titanium dioxide 63.5-65 Copper nitrate 1.9-2.2 Pseudoboehmite 1.0-1.2 Antimony acetate 1.3-1.6 Ammonium metavanadate - monoethanolamine aqueous solution 11-13 Silica sol 1.5-2.5 Ammonium heptamolybdate 2.0-2.3 Lactic acid 0.4-0.8 Ammonium metatungstate 1.3-1.6 Ammonia water 3.5-5 Glass fiber 5-5.5 Sesbania powder 0.5-1 Cerium nitrate 1.1-1.5 Polyoxyethylene 0.5-1

[0061] Among them, the ammonium metavanadate - monoethanolamine aqueous solution is a homogeneous solution obtained by stirring and mixing ammonium metavanadate, monoethanolamine, and water in a mass ratio of 1:1:3 at 75°C ± 5°C until evenly mixed; the glass fiber is 6mm glass fiber; the silica sol is a 25% silica sol solution; the viscosity of polyethylene oxide is 250 mPa·s; the specific surface area of anatase titanium dioxide is 100 m 2 / g, with a particle size distribution D50 of 1.2 μm; pseudo-boehmite Al2O3·nH2O (n = 0.55); the viscosity of sesbania powder is 850 mPa·s; the ammonia water concentration is 25-27%; the glass fiber is an alkali-free glass fiber.

[0062] The mass parts composition of Examples 1-4 and Comparative Examples 1-2 is shown in Table 2 as follows:

[0063] Table 2

[0064]

[0065] During the preparation process, taking the mass parts of anatase titanium dioxide as the initial standard, the rest of the raw materials are weighed successively according to the ratio.

[0066] The preparation process of the denitrification and mercury co-removal SCR honeycomb catalysts of Examples 1-4 is as follows:

[0067] (1) After mixing anatase titanium dioxide, silica sol, and pseudo-boehmite evenly in a kneader, deionized water is added until the water content is 38%. The obtained slurry mixture is mixed and stirred evenly at 60 °C to obtain mixture A;

[0068] (2) Ammonium metatungstate, cerium nitrate, copper nitrate, and antimony acetate are added to mixture A and mixed evenly to obtain mixture B;

[0069] (3) After adding ammonia water to adjust the pH value of the reaction system to 8.2 in the obtained mixture B, ammonium heptamolybdate is added and mixed evenly. Then, an ammonium metavanadate-monoethanolamine aqueous solution is added, and after stirring for 60 min, the temperature is raised to remove moisture until the moisture content of the mud in the kneader is 34% to obtain mixture C;

[0070] (4) The mixture C is heated and stirred for 40 min. After adjusting the system water content to 30%, lactic acid is added to adjust the pH value to 7.6, then glass fiber is added and mixed and stirred. After that, sesbania powder and polyoxyethylene are added, and the system water content is adjusted to 28%. Then, aging treatment is carried out to obtain the aged mud D.

[0071] (5) The aged mud D is extruded into strip-shaped mud through a pre-extruder. After removing the impurities in the mud, honeycomb catalyst monomers are extruded through an extrusion die (30 holes).

[0072] (6) The extruded honeycomb catalyst monomers are dried in two stages and then calcined. The calcination temperature is 500 °C and the calcination time is 35 h to obtain the denitrification and mercury co-removal SCR honeycomb catalysts.

[0073] Among them, the two-stage drying is specifically as follows:

[0074] First-stage drying: First, dry for 2 days at a humidity of 80% and a temperature of 40°C, then dry for 4 days at a humidity of 60% and a temperature of 45°C, and finally dry for 2 days at a humidity of 20% and a temperature of 55°C. The temperature of the second-stage drying is 60°C and the time is 24 h.

[0075] The physical diagram of the denitration and mercury co-removal SCR honeycomb catalyst prepared in Example 1 of the present invention is shown in Figure 3 .

[0076] The preparation process of the catalyst of Comparative Example 1 is as follows:

[0077] (1) After adding anatase titanium dioxide to a kneader and kneading evenly, add deionized water until the water content is 38%, and mix and stir the obtained slurry mixture evenly at 60°C to obtain mixture A;

[0078] (2) After adding ammonia water to the obtained mixture A to adjust the pH of the reaction system to 8.2, add ammonium heptamolybdate and mix evenly, then add an aqueous solution of ammonium metavanadate - monoethanolamine, stir for 60 min, and then heat up to remove moisture until the moisture content of the mud in the kneader is 34% to obtain mixture B;

[0079] (3) Heat and stir mixture B for 40 min. After the water content of the condition system is 30%, add lactic acid to adjust the pH value to 7.6, then add glass fiber, knead for 40 min, adjust the moisture content of the mud to 30%, then add sesbania powder and polyethylene oxide, continue to stir and adjust until the moisture content of the mixed material is 28% and the pH value is 7.6, and then continue to age in the kneader for 8 h to obtain aged mud C.

[0080] (4) Extrude the aged mud C into strip-shaped mud through a pre-extruder, remove the impurities in the mud, and then extrude honeycomb catalyst monomers through an extrusion die (30 holes).

[0081] (5) After drying the extruded honeycomb catalyst monomers in two stages (the two-stage drying is the same as in Example 1), calcine them at a calcination temperature of 500°C and a calcination time of 35 h to obtain the catalyst.

[0082] The preparation process of the catalyst of Comparative Example 2 is as follows:

[0083] (1) After adding anatase titanium dioxide to a kneader and kneading evenly, add deionized water until the water content is 38%, and mix and stir the obtained slurry mixture evenly at 60°C to obtain mixture A;

[0084] (2) Add ammonium metatungstate to mixture A to obtain mixture B;

[0085] (3) After adding ammonia water to the obtained mixture B to adjust the pH of the reaction system to 8.2, an ammonium metavanadate-monoethanolamine aqueous solution was added. After stirring for 60 min, the mixture was heated to remove moisture until the moisture content of the mud in the kneader was 34%, obtaining mixture C;

[0086] (4) The mixture C was heated and stirred for 40 min. After adjusting the moisture content of the system to 30%, lactic acid was added to adjust the pH value to 7.6, and then glass fiber was added. After kneading for 40 min, the moisture content of the mud was adjusted to 30%. Then, sesbania powder and polyethylene oxide were added, and stirring was continued to adjust the moisture content of the mixed material to 28% and the pH value to 7.6. Then, it was aged in the kneader for 8 h to obtain the aged mud D.

[0087] (5) The aged mud D was extruded into strip-shaped mud through a pre-extruder. After removing impurities from the mud, it was extruded through an extrusion die (30 holes) to obtain honeycomb catalyst monomers.

[0088] (6) The extruded honeycomb catalyst monomers were calcined after two-stage drying (the two-stage drying was the same as in Example 1). The calcination temperature was 500 °C and the calcination time was 35 h to obtain the catalyst.

[0089] The component contents of the catalysts prepared in Example 1 and Comparative Examples 1-2 of the present invention are shown in Table 3, where the component contents were characterized by XRF (X-ray fluorescence spectrometer).

[0090] Table 3

[0091] Sample <![CDATA[TiO2]]> <![CDATA[V2O5]]> <![CDATA[MoO3]]> <![CDATA[Sb2O3]]> <![CDATA[CeO2]]> <![CDATA[WO3]]> CuO <![CDATA[SO3]]> <![CDATA[Na2O]]> (％) (％) (％) (％) (％) (％) (％) (％) (％) Example 1 81.318 2.25 2.008 0.874 0.998 1.615 0.75 1.187 0.212 Comparative Example 1 83.503 2.13 2.209 / / / / 2.837 0.262 Comparative Example 2 84.563 2.23 / / / 1.716 / 2.076 0.259 Sample MgO <![CDATA[Al2O3]]> <![CDATA[SiO2]]> <![CDATA[P2O5]]> <![CDATA[K2O]]> CaO <![CDATA[Fe2O3]]> <![CDATA[ZrO2]]> <![CDATA[Nb2O5]]> (％) (％) (％) (％) (％) (％) (％) (％) (％) Example 1 0.203 1.214 5.001 0.014 0.036 2.17 0.111 0.014 0.025 Comparative Example 1 0.161 0.909 5.781 0.015 0.053 1.996 0.102 0.013 0.029 Comparative Example 2 0.162 1.001 5.802 0.006 0.057 1.987 0.099 0.015 0.027

[0092] The specific surface area, pore volume, and pore diameter of the catalysts prepared in Examples 1-4 and Comparative Examples 1-2 of the present invention are shown in Table 4.

[0093] Table 4

[0094]

[0095] The radial compressive strength and axial compressive strength of the catalysts prepared in Examples 1-4 and Comparative Examples 1-2 of the present invention are shown in Table 5.

[0096] Table 5

[0097]

[0098] The catalysts prepared in Examples 1-4 and Comparative Examples 1-2 were placed at 200-380 °C, with flue gas components NO (400 mg / Nm 3 ), O2 (5%), ammonia-nitrogen molar ratio of 1, SO2 (400 mg / Nm 3 ), Hg (450 ng / m 3 ), the carrier gas was N2, and the reaction space velocity was 4000 h -1In the flue gas environment, the denitrification efficiency and the oxidation rate of elemental Hg were measured.

[0099] The measurement results of the oxidation rate of elemental Hg in the flue gas are shown in Table 6 and Figure 1 .

[0100] Table 6

[0101]

[0102]

[0103] The measurement results of the denitrification efficiency are shown in Table 7 and Figure 2 .

[0104] Table 7

[0105]

[0106] The embodiments described above are only descriptions of the preferred modes of the present invention, and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, various deformations and improvements made by those of ordinary skill in the art to the technical solutions of the present invention should fall within the protection scope determined by the claims of the present invention.

Claims

1. A denitrification and mercury co-removal SCR honeycomb catalyst, characterized in that, Comprising the following raw material components in parts by mass: 63.5 - 65 parts of anatase catalytic titanium dioxide, 1.0 - 1.2 parts of pseudo - boehmite, 11 - 13 parts of ammonium metavanadate - monoethanolamine aqueous solution, 2.0 - 2.3 parts of ammonium heptamolybdate, 1.3 - 1.6 parts of ammonium metatungstate, 5 - 5.5 parts of glass fiber, 1.1 - 1.5 parts of cerium nitrate, 1.9 - 2.2 parts of copper nitrate, 1.3 - 1.6 parts of antimony acetate, 1.5 - 2.5 parts of silica sol, 0.5 - 1 part of sesbania powder, and 0.5 - 1 part of polyoxyethylene; The preparation method of the denitrification and mercury - co - removal SCR honeycomb catalyst comprises the following steps: (1) Mix anatase titanium dioxide, silica sol, pseudo - boehmite and water so that the water content of the system is 38% - 39%, and stir - mix at 60 - 80 °C to obtain mixture A; (2) Add ammonium metatungstate, cerium nitrate, copper nitrate and antimony acetate to the obtained mixture A and mix to obtain mixture B; (3) Adjust the pH value of mixture B to 8.2 - 8.5, then add ammonium heptamolybdate and ammonium metavanadate - monoethanolamine aqueous solution, and control the water content of the system to be 33% - 34% to obtain mixture C; (4) Carry out temperature - rising stirring on mixture C, adjust the water content of the system to 30% - 31%, then adjust the pH value to 7.6 - 8.0, add glass fiber and stir - mix, then add sesbania powder and polyoxyethylene, control the water content of the system to be 26% - 29%, then carry out aging treatment, extrude and form the obtained aged mud material, dry it and then carry out calcination treatment to obtain the denitrification and mercury - co - removal SCR honeycomb catalyst.

2. The denitrification and mercury co-removal SCR honeycomb catalyst according to claim 1, wherein The ammonium metavanadate - monoethanolamine aqueous solution is a homogeneous solution obtained by mixing ammonium metavanadate, monoethanolamine and water in a mass ratio of 1:1:3 at 75 °C ± 5 °C.

3. The preparation method of the SCR honeycomb catalyst for denitrification and mercury co-removal according to claim 1, characterized in that, Comprising the following steps: (1) Mix anatase titanium dioxide, silica sol, pseudo - boehmite and water so that the water content of the system is 38% - 39%, and stir - mix at 60 - 80 °C to obtain mixture A; (2) Add ammonium metatungstate, cerium nitrate, copper nitrate and antimony acetate to the obtained mixture A and mix to obtain mixture B; (3) Adjust the pH value of mixture B to 8.2 - 8.5, then add ammonium heptamolybdate and ammonium metavanadate - monoethanolamine aqueous solution, and control the water content of the system to be 33% - 34% to obtain mixture C; (4) Carry out temperature - rising stirring on mixture C, adjust the water content of the system to 30% - 31%, then adjust the pH value to 7.6 - 8.0, add glass fiber and stir - mix, then add sesbania powder and polyoxyethylene, control the water content of the system to be 26% - 29%, then carry out aging treatment, extrude and form the obtained aged mud material, dry it and then carry out calcination treatment to obtain the denitrification and mercury - co - removal SCR honeycomb catalyst.

4. A denitrification and mercury co-removal SCR honeycomb catalyst, characterized in that, Comprising the following raw material components in parts by mass: 63.5 - 65 parts of anatase catalytic titanium dioxide, 1.0 - 1.2 parts of pseudo - boehmite, 11 - 13 parts of ammonium metavanadate - monoethanolamine aqueous solution, 2.0 - 2.3 parts of ammonium heptamolybdate, 1.3 - 1.6 parts of ammonium metatungstate, 5 - 5.5 parts of glass fiber, 1.1 - 1.5 parts of cerium nitrate, 1.9 - 2.2 parts of copper nitrate, 1.3 - 1.6 parts of antimony acetate, 1.5 - 2.5 parts of silica sol, 0.5 - 1 part of sesbania powder, 0.5 - 1 part of polyoxyethylene, 3.5 - 5 parts of ammonia water, and 0.4 - 0.8 part of lactic acid; The preparation method of the denitrification and mercury - removal synergistic SCR honeycomb catalyst comprises the following steps: (1) Mix anatase titanium dioxide, silica sol, pseudo - boehmite and water so that the water content of the system is 38% - 39%, and stir and mix at 60 - 80 °C to obtain mixture A; (2) Add ammonium metatungstate, cerium nitrate, copper nitrate and antimony acetate to the obtained mixture A and mix to obtain mixture B; (3) Add ammonia water to make the pH value of mixture B 8.2 - 8.5, then add ammonium heptamolybdate and ammonium metavanadate - monoethanolamine aqueous solution, and adjust the water content of the system to 33% - 34% to obtain mixture C; (4) Carry out heating and stirring on mixture C. After adjusting the water content of the system to 30 - 31%, add lactic acid to adjust the pH value to 7.6 - 8.0, then add glass fiber and mix and stir. After that, add sesbania powder and polyoxyethylene, adjust the water content of the system to 26 - 29%, then carry out aging treatment. Extrude and form the obtained aged mud material, dry it and then carry out calcination treatment to obtain the denitrification and mercury - removal synergistic SCR honeycomb catalyst.

5. The preparation method of the SCR honeycomb catalyst for denitrification and mercury co-removal according to claim 4, characterized in that, Comprises the following steps: (1) Mix anatase titanium dioxide, silica sol, pseudo - boehmite and water so that the water content of the system is 38% - 39%, and stir and mix at 60 - 80 °C to obtain mixture A; (2) Add ammonium metatungstate, cerium nitrate, copper nitrate and antimony acetate to the obtained mixture A and mix to obtain mixture B; (3) Add ammonia water to make the pH value of mixture B 8.2 - 8.5, then add ammonium heptamolybdate and ammonium metavanadate - monoethanolamine aqueous solution, and adjust the water content of the system to 33% - 34% to obtain mixture C; (4) Carry out heating and stirring on mixture C. After adjusting the water content of the system to 30 - 31%, add lactic acid to adjust the pH value to 7.6 - 8.0, then add glass fiber and mix and stir. After that, add sesbania powder and polyoxyethylene, adjust the water content of the system to 26 - 29%, then carry out aging treatment. Extrude and form the obtained aged mud material, dry it and then carry out calcination treatment to obtain the denitrification and mercury - removal synergistic SCR honeycomb catalyst.

6. Application of the denitrification and mercury - removal synergistic SCR honeycomb catalyst according to claim 1 or 4 in flue gas denitrification and / or mercury removal.

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