KR102265558B1 - High strength honeycomb structures for selective catalystic reduction catalyst and method of manufacturing the same - Google Patents

Abstract

The present invention relates to titania carrier particles formed from a composition for preparing a carrier comprising a silicon dioxide compound and a raw metatitanic acid in a weight ratio of 1:9 to 1:11, and silicon dioxide supported on the surface; It relates to a honeycomb structure for a selective catalytic reduction catalyst comprising a, and a method for preparing the same. Through this, the present invention has excellent abrasion resistance and strength, can reduce physical damage due to wear and drift, has a high degree of strength improvement over time, and has excellent compressive strength and hardness. Honeycomb structure for selective catalytic reduction catalyst and economical thereof A method for preparing phosphorus is provided.

Description

HIGH STRENGTH HONEYCOMB STRUCTURES FOR SELECTIVE CATALYSTIC REDUCTION CATALYST AND METHOD OF MANUFACTURING THE SAME

The present invention relates to a honeycomb structure for a high-strength selective catalytic reduction catalyst and a method for preparing the same.

The Selective Catalytic Reduction (SCR) facility is one of the exhaust gas post-treatment facilities. It converts nitrogen oxides (NOx) generated from facilities that use high-temperature combustion reactions such as thermal power plants, incinerators, and chemical plants into non-hazardous substances. used to do

The selective catalytic reduction facility mixes ammonia, a reducing agent, with exhaust gas at a relatively low temperature of 200°C to 500°C, and then reduces nitrogen oxides in the catalyst layer to harmless nitrogen and water vapor and discharges them.

On the other hand, in recent thermal power plants, etc., there are cases in which low-calorie coal is used for cost reduction. The combustion of low calorie coal increases the flow rate of exhaust gas and the amount of fly ash generated, thereby continuously increasing the non-uniformity of the exhaust gas flow rate and pressure loss due to side-flow. In this case, wear and tear may occur not only in the selective catalytic reduction catalyst, but also in a guide vane, a baffle plate, a duct, etc., which are structures of a flue gas denitration facility.

The wear and tear of the selective catalytic reduction catalyst primarily causes a decrease in denitration performance and an increase in the amount of reducing agent used, thereby increasing the cost of post-treatment of exhaust gas. In addition, wear and tear of the selective catalytic reduction catalyst may cause excessive generation of viscous by-products such as ammonium sulfate and ammonium bisulfate by changing the operating conditions of the exhaust gas post-treatment facility outside the assumed range. In this case, the differential pressure in the equipment increases, which may cause secondary problems such as desensitization or operation shutdown.

Accordingly, there is an increasing demand for the development of a structure for a selective catalytic reduction catalyst having excellent wear resistance and strength in order to solve the above problems.

The prior art of the present invention is described in Korean Patent No. 10-0641694 and Korean Patent No. 10-1042018.

One object of the present invention is to provide a honeycomb structure for a high-strength selective catalytic reduction catalyst that has excellent abrasion resistance and strength, and can reduce physical damage due to wear and drift, and a method for manufacturing the same.

Another object of the present invention is to provide a honeycomb structure for a high-strength selective catalytic reduction catalyst having high strength improvement over time and excellent compressive strength and hardness, and a method for manufacturing the same.

All of the above and other objects of the present invention can be achieved by the present invention described below.

One embodiment of the present invention is formed from a composition for preparing a carrier comprising a silicon dioxide compound and a raw metatitanic acid in a weight ratio of 1:9 to 1:11, and silicon dioxide is supported on the surface of the titania carrier particles; It relates to a honeycomb structure for a selective catalytic reduction catalyst comprising a.

The carrier particle has an anatase titania crystalline phase, sulfur trioxide (SO ₃ ) 1 wt% to 2 wt%; 1 wt% to 5 wt% tungsten trioxide (WO _{3 );} Silicon dioxide (SiO ₂ ) 4% to 20% by weight; And titanium dioxide (TiO ₂ ) It may contain 75 wt% to 90 wt%.

The honeycomb structure for the selective catalytic reduction catalyst may include the support particles; catalytically active substances; organic binders; and an inorganic binder, and may have a moisture content of 25% to 40%, and a plasticity of 30% to 50%, which may be formed from a kneaded clay composition.

The honeycomb structure for the selective catalytic reduction catalyst may have a cross-sectional compressive strength of 13 kgf/cm ² or more, and a longitudinal compressive strength of 30 kgf/cm ^{2 or} more.

The honeycomb structure for the selective catalytic reduction catalyst may have an abrasion rate of 8% or less, expressed by Equation 1 below.

<Equation 1>

Wear rate (%) = {│( W ₀ - W ₁ )│ / W ₀ } × 100

(In Equation 1, W ₀ is the mass measured before the abrasion test of the honeycomb structure specimen having an external size of 42 mm x 42 mm x 100 mm (width x length x length, thickness: 0.6 mm),

W ₁ is the mass measured after performing a wear test on the specimen at a flow rate of 17 m/s and an abrasive discharge amount of 25 kg/h for 30 minutes.

Another embodiment of the present invention comprises the steps of heat-treating a composition for preparing a carrier comprising a silicon dioxide compound and a raw meta-titanic acid in a weight ratio of 1:9 to 1:11 to prepare titania carrier particles having silicon dioxide supported on the surface. ; preparing a clay composition by mixing and kneading the support particles, a catalytically active material, an organic binder, and an inorganic binder; and extruding the clay composition into a honeycomb shape, drying and calcining to prepare a honeycomb structure; It relates to a method for manufacturing a honeycomb structure for a selective catalytic reduction catalyst comprising a.

The step of preparing the carrier particles may include neutralizing the metatitanic acid raw material with ammonia, then mixing it with a silicon dioxide compound dispersion or impregnating it with a colloidal silicon dioxide solution, followed by heat treatment.

The heat treatment may be performed at 500° C. to 700° C. for 1 hour to 4 hours.

The carrier particles have an anatase titania crystalline phase, and contain 1 wt% to 2 wt% of sulfur trioxide; 1 wt% to 5 wt% tungsten trioxide; 4% to 20% by weight of silicon dioxide; and 75 wt% to 90 wt% of titanium dioxide.

Preparing the soil composition may include adjusting the moisture content of the soil composition to 25% to 40%, and the plasticity to 30% to 50%.

The present invention provides a honeycomb structure for a selective catalytic reduction catalyst that has excellent wear resistance and strength, can reduce physical damage caused by wear and drift, has a high degree of strength improvement over time, and has excellent compressive strength and hardness, and a method for manufacturing the same do.

1 shows the evaluation results of extrusion formability of the honeycomb structure prepared in Example 1 of the present invention.
2 shows the evaluation results of extrusion formability of the honeycomb structure prepared in Comparative Example 1 of the present invention.
3 shows the evaluation results of extrusion formability of the honeycomb structure prepared in Comparative Example 2 of the present invention.
4 shows the evaluation results of extrusion formability of the honeycomb structure prepared in Comparative Example 3 of the present invention.
5 shows the results of evaluation of the wear rate of the honeycomb structure manufactured in Example 1 of the present invention.
6 shows the evaluation results of the wear rate of the honeycomb structure manufactured in Comparative Example 1 of the present invention.

One embodiment of the present invention is formed from a composition for preparing a carrier comprising a silicon dioxide compound and a raw metatitanic acid in a weight ratio of 1:9 to 1:11, and silicon dioxide is supported on the surface of the titania carrier particles; It relates to a honeycomb structure for a selective catalytic reduction catalyst comprising a.

Through this, the present invention provides a honeycomb structure for a selective catalytic reduction catalyst that has excellent abrasion resistance and strength, can reduce physical damage due to wear and drift, has a high degree of strength improvement over time, and has excellent compressive strength and hardness. .

In particular, when the honeycomb structure of the present invention is applied as a catalyst structure to a selective catalytic reduction facility of a thermal power plant, it prevents direct wear and damage caused by the non-uniformity and drift of the flow rate caused by the fly ash contained in the exhaust gas. the effect is very good.

The carrier particles are produced using a raw metatitanic acid and a silicon dioxide compound as raw materials, and are titania carrier particles formed by supporting a silicon dioxide compound on the surface of a metatitanic acid raw material. The carrier particle is a calcined (heat-treated) body of a composition for preparing a carrier including a raw metatitanic acid and a silicon dioxide compound.

The meta-titanic acid raw material is converted to titania while being accompanied by a dehydration reaction from _{meta-titanic acid (TiO(OH 2} )) molecules in the heat treatment process during loading, as compared with the case of using a conventional titania carrier. Accordingly, the support particle can further improve the support and distribution of silicon dioxide, and even at a relatively low heat treatment temperature, titania and silicon dioxide form a stronger bond, thereby further improving the strength of the support particle.

The metatitanic acid raw material has a specific surface area (BET) of 80 m / g to 120 m / g, for example, 81.6 m / g to 91.6 m / g, and a pore volume of 0.2 cm 3 /g to 0.3 cm 3 /g , having a pore diameter between 9 nm and 13 nm, for example between 10.7 nm and 12.3 nm can be Within the above range, the raw metatitanic acid may further improve the abrasion resistance and strength of the carrier particles and the honeycomb structure for the selective catalytic reduction catalyst including the same. The specific surface area, pore volume, and pore size were measured by adding 0.5 g of the raw material to the cell using a surface characterization analyzer (Tristar II3020, Micromeritics, USA), raising the temperature to 300 ° C. degassing), and measuring 17 points of adsorption and desorption by an analysis method using nitrogen gas.

The metatitanic acid raw material has a D10 particle size of 0.4 μm to 1 μm, for example, 0.423 μm to 0.707 μm, a D50 particle size of 1 μm to 2 μm, for example, 1.026 μm to 1.732 μm, D90 particle size 1 μm to 5 μm, For example, it may be 1.693 μm to 3.370 μm. Within the above range, the meta-titanic acid raw material may further improve the abrasion resistance and strength of the carrier particles and the honeycomb structure for the selective catalytic reduction catalyst including the same. The D10 particle diameter, D50 particle diameter, and D90 particle diameter are measured using a particle size analyzer (Microtrac Bluewave particle size analyzer, Betaeck Inc.) which is applied and measured according to the principle of a laser diffraction (scattering) method.

The metatitanic acid raw material may have a packing density of 0.5 g/cm ³ to 0.7 g/cm ³ , for example, 0.62 g/cm ³ to 0.65 g/cm ³ . Within the above range, the raw metatitanic acid may further improve the abrasion resistance and strength of the carrier particles and the honeycomb structure for the selective catalytic reduction catalyst including the same. The packing density is calculated as the average value after reducing the volume by tapping the powder sample, measuring the increase in the tap density three times using a tap-density analyzer.

The silicon dioxide compound may be, for example, clay containing 98% or more of silicon dioxide, or colloidal silica. In one embodiment, when the clay is used as the silicon dioxide compound, it is possible to obtain the effect of more easily controlling the moisture content and plasticity when applied to the clay composition while reducing the production cost. In another embodiment, when colloidal silica is used as the silicon dioxide compound, it is possible to obtain the effect of more uniformly improving the particle distribution of the carrier particles, and more smoothly dispersing and supporting the particles.

The silicon dioxide compound and the metatitanic acid raw material in the composition for preparing the support are included in a weight ratio of 1:9 to 1:11, so that the produced support particles further improve the extrusion moldability of the honeycomb structure for the selective catalytic reduction catalyst, and at the same time It can improve shape retention, abrasion resistance and strength. When the weight of the silicon dioxide compound and the weight of the metatitanic acid raw material is less than 9 times (less than 1:9), shape retention is deteriorated during the manufacture of the honeycomb structure for the selective catalytic reduction catalyst, and defects may occur in the extrusion appearance. When the weight of the silicon dioxide compound and the weight of the metatitanic acid raw material is more than 11 times (exceeding 1:11), fluidity may be reduced during the manufacture of the honeycomb structure for the selective catalytic reduction catalyst, and physical damage may occur due to pressure increase.

The carrier particles may have an anatase-type titania crystal phase. In this case, when the carrier particles are applied to a honeycomb structure for a selective catalytic reduction catalyst, the reduction reaction of the catalyst can proceed more smoothly as compared to the case in which the carrier particles have a rutile-type titania crystal phase.

The anatase-type titania crystalline phase of the carrier particles may be achieved by controlling the heat treatment temperature during support, for example, by performing heat treatment at 500°C to 700°C. Within the above range, it is possible to further increase the fraction of the anatase-type crystal phase of the carrier particles and further reduce the phase transition to the rutile-type titania crystal phase.

The carrier particles may additionally include sulfur trioxide and/or tungsten trioxide in addition to the titania component derived from the metatitanic acid raw material and the silicon dioxide component derived from the silicon dioxide compound. In this case, sulfur trioxide and/or tungsten trioxide may be partially derived from the raw material during the preparation process of the meta-titanic acid raw material. In this case, sulfur trioxide and/or tungsten trioxide among the support particles form acid sites on the surface of the titania component of the support particles, and when applied to a honeycomb structure for a selective catalytic reduction catalyst, it is possible to further increase the active reaction of the catalyst, and It is possible to further improve the binding force during the preparation of the composition.

Specifically, the carrier particles may contain 1 wt% to 2 wt% of sulfur trioxide; 1 wt% to 5 wt% tungsten trioxide; 4% to 20% by weight of silicon dioxide; and 75 wt% to 90 wt% of titanium dioxide. Within the above range, the carrier particles may further increase the active reaction of the catalyst and further improve abrasion resistance and strength when applied to the honeycomb structure for the selective catalytic reduction catalyst.

The honeycomb structure for a selective catalytic reduction catalyst of the present invention includes the support particles. Specifically, the honeycomb structure for the selective catalytic reduction catalyst may be formed from a soil composition including the support particles. More specifically, the honeycomb structure for the selective catalytic reduction catalyst may be a dried and fired body of the soil composition including the support particles.

The clay composition comprises, in the carrier particles, a catalytically active material; organic binders; inorganic binders; One or more of these may be additionally included. In one embodiment, the clay composition comprises a carrier particle; catalytically active substances; organic binders; and inorganic binders. In this case, the elongation and yield stress of the clay composition may be improved, and the moisture content and plasticity may be adjusted to an appropriate range, thereby further improving extrusion moldability.

The content of the carrier particles in the kneaded clay composition may be 75 wt% to 90 wt%. Within the above range, it is possible to improve mechanical properties, abrasion resistance, and strength when manufacturing a honeycomb structure for a selective catalytic reduction catalyst.

The catalytically active material is not particularly limited as input for catalytic activity of the honeycomb structure for the selective catalytic reduction catalyst. A catalyst component and/or a crude catalyst component, such as tungsten oxide or vanadium oxide, may be used individually by 1 type, or in mixture of 2 or more types, respectively.

The content of the catalytically active material in the kneaded clay composition may be 0.5 wt% to 20 wt%. Within the above range, it is possible to further promote catalytic activity in the preparation of the honeycomb structure for a selective catalytic reduction catalyst, and at the same time improve mechanical properties, abrasion resistance and strength.

The organic binder binds the components in the clay composition, serves to improve compatibility, and serves to physically and chemically reinforce the shape of the honeycomb structure for the selective catalytic reduction catalyst. The organic binder may be excellent in extrusion moldability when manufacturing a honeycomb structure for a selective catalytic reduction catalyst and at the same time more excellent in shape retention.

The content of the organic binder in the kneaded clay composition may be 1 wt% to 5 wt%. Within the above range, it is possible to further improve extrusion moldability when manufacturing a honeycomb structure for a selective catalytic reduction catalyst, and at the same time improve mechanical properties, abrasion resistance and strength.

The inorganic binder binds the components in the clay composition, serves to improve compatibility, and serves to physically and chemically reinforce the shape of the honeycomb structure for the selective catalytic reduction catalyst.

The inorganic binder may be, for example, at least one of alumina, glass, water glass, and glass fiber. Each of the inorganic binders of the above examples may be used alone or as a mixture of two or more. In this case, when the honeycomb structure for the selective catalytic reduction catalyst is manufactured, the extrusion moldability may be excellent and the shape retention property may be further excellent. The glass fibers are re-agglomerated after being dispersed in the clay composition, thereby further improving extrusion moldability during the manufacture of the honeycomb structure for a selective catalytic reduction catalyst and at the same time further improving abrasion resistance and strength.

The content of the inorganic binder in the kneaded clay composition may be 1 wt% to 20 wt%. Within the above range, it is possible to further improve extrusion moldability when manufacturing a honeycomb structure for a selective catalytic reduction catalyst, and at the same time improve mechanical properties, abrasion resistance and strength.

The kneaded clay composition may have a moisture content of 25% to 40%, and a plasticity of 30% to 50%. Within the above range, the yield stress, bonding strength, and plasticity of the clay composition are further improved, thereby further improving extrusion moldability and shape retention in the manufacture of a honeycomb structure for a selective catalytic reduction catalyst.

The selective catalytic reduction honeycomb structure of the catalyst and the cross-sectional direction the compressive strength can be 13kgf / cm ² or more, for example 13kgf / cm ² to 35 kgf / cm ^2, specifically, 13kgf / cm ² to 25 kgf / cm greater than ^2, The longitudinal compressive strength may be 30 kgf/cm ² or more, specifically 30 kgf/cm ² to 55 kgf/cm ² , and more specifically 30 kgf/cm ² to 45 kgf/cm ² . Within the above range, it is possible to further improve the abrasion resistance and strength of the honeycomb structure for the selective catalytic reduction catalyst, further reduce physical damage due to wear and drift, increase the strength improvement over time, and further improve the compressive strength and hardness have.

The honeycomb structure for the selective catalytic reduction catalyst may have an abrasion rate of 8% or less, specifically 0.1% to 8%, and more specifically 1% to 8%, expressed by Equation 1 below. Within the above range, it is possible to further improve the abrasion resistance and strength of the honeycomb structure for the selective catalytic reduction catalyst, further reduce physical damage due to wear and drift, increase the strength improvement over time, and further improve the compressive strength and hardness have.

<Equation 1>

Wear rate (%) = {│( W ₀ - W ₁ )│ / W ₀ } × 100

(In Equation 1, W ₀ is the mass measured before the abrasion test of the honeycomb structure specimen having an external size of 42 mm x 42 mm x 100 mm (width x length x length, thickness: 0.6 mm), and W ₁ is the specimen It is the mass measured after abrasion test for 30 minutes at a flow rate of 17 m/s and an abrasive discharge amount of 25 kg/h).

Another embodiment of the present invention is to prepare carrier particles in which the silicon dioxide compound is supported on the metatitanic acid raw material in a weight ratio of 1:9 to 1:11 by adding the metatitanic acid raw material to the silicon dioxide compound solution, and then performing heat treatment. step; mixing and kneading a catalytically active material, an organic binder and an inorganic binder with the support particles to prepare a clay composition; and extruding the kneaded clay composition into a honeycomb shape, drying and calcining to prepare a honeycomb structure; It relates to a method for manufacturing a honeycomb structure for a selective catalytic reduction catalyst comprising a. Through this, the honeycomb structure for the selective catalytic reduction catalyst of the present invention described above can be manufactured more economically and with excellent efficiency.

Specific details of each component used in the method for manufacturing the honeycomb structure for the selective catalytic reduction catalyst are the same as described above.

In the step of preparing the carrier particles, a composition for preparing a carrier including a raw metatitanic acid and a silicon dioxide compound is prepared, and the carrier particle is prepared by heat treatment.

Specifically, the step of preparing the carrier particles may include neutralizing the metatitanic acid raw material with ammonia and then mixing it with a silicon dioxide compound dispersion or impregnating it with a colloidal silicon dioxide solution, followed by heat treatment.

The meta-titanic acid raw material may be formed by, for example, hydrolyzing titanium sulfate to form primary particles of 10 nm or less, and then preparing secondary aggregated particles of 0.5 μm to 2.5 μm. In this case, the meta-titanic acid raw material may contain some sulfur compounds during the manufacturing process.

The meta-titanic acid raw material may be used _{after being neutralized with ammonia (NH 3 ) after washing with water.} In this case, ions including sulfur atoms included in the metatitanic acid raw material may be combined with ammonia and removed with ammonium sulfate. In this case, the removal rate of unnecessary sulfur compounds from the carrier particles may be increased, and some sulfur trioxide may form acid sites on the surface of the titania component of the carrier particles.

The composition for preparing the carrier may be prepared by mixing the raw metatitanic acid with a silicon dioxide compound dispersion or impregnating it with a colloidal silicon dioxide solution.

The silicon dioxide compound dispersion may be, for example, a clay dispersion containing 98% or more of silicon dioxide. In this case, it is possible to obtain the effect of more easily controlling the moisture content and plasticity when applied to the soil composition while reducing the production cost of the carrier particles. The colloidal silica solution may be prepared by, for example, an ion exchange method using sodium silicate and water as raw materials. In this case, it is possible to obtain the effect of more uniformly improving the particle distribution of the carrier particles, and more smoothly dispersing and carrying.

The heat treatment may be performed at 500° C. to 700° C. for 1 hour to 4 hours. Within the above range, it is possible to further increase the fraction of the anatase-type crystal phase of the carrier particles and further reduce the phase transition to the rutile-type titania crystal phase.

The preparing of the carrier particles may include preparing the carrier particles having an anatase-type titania crystal phase. In this case, when the carrier particles are applied to a honeycomb structure for a selective catalytic reduction catalyst, the reduction reaction of the catalyst can proceed more smoothly, compared to the case in which the carrier particles have a rutile-type titania crystal phase.

The preparing of the carrier particles may include preparing the carrier particles additionally comprising sulfur trioxide and/or tungsten trioxide in addition to the titania component derived from the meta-titanic acid raw material and the silicon dioxide component derived from the silicon dioxide compound.

Specifically, the carrier particles may contain 1 wt% to 2 wt% of sulfur trioxide; 1 wt% to 5 wt% tungsten trioxide; 4% to 20% by weight of silicon dioxide; and 75 wt% to 90 wt% of titanium dioxide. Within the above range, the carrier particles may further increase the active reaction of the catalyst and further improve abrasion resistance and strength when applied to the honeycomb structure for the selective catalytic reduction catalyst.

The step of preparing the clay composition comprises: a catalytically active material to the support particles; organic binders; inorganic binders; One or more of them are additionally mixed and then kneaded, including preparing a clay composition. Specific components and their contents included in the clay composition are as described above. The kneading method of the soil composition is not particularly limited, and a general method for preparing the soil composition may be employed.

In one embodiment, the clay composition comprises a carrier particle; catalytically active substances; organic binders; All inorganic binders may be included. In this case, the elongation and yield stress of the clay composition may be improved, and the moisture content and plasticity may be adjusted to an appropriate range, thereby further improving extrusion moldability.

The step of preparing the kneaded clay composition may include adjusting the moisture content of the clay composition to 25% to 40%, and the plasticity to 30% to 50%. In this case, the yield stress, bonding strength, and plasticity of the clay composition are further improved, thereby further improving extrusion moldability and shape retention when manufacturing the honeycomb structure for a selective catalytic reduction catalyst.

The manufacturing of the honeycomb structure includes extruding the clay composition into a honeycomb shape, drying and calcining, to prepare a honeycomb structure for a selective catalytic reduction catalyst.

The extrusion may be performed in a vacuum extrusion method at room temperature, but is not limited thereto. In this case, the abrasion resistance and strength of the honeycomb structure for the selective catalytic reduction catalyst can be further improved.

The drying may be performed, for example, at 30° C. to 70° C. for 6 hours to 18 hours. In this case, the occurrence of dry cracks in the honeycomb structure for the selective catalytic reduction catalyst can be prevented, and the abrasion resistance and strength can be further improved.

The firing may be performed, for example, in a hot air method in a continuous firing furnace at 300° C. to 600° C. for 6 hours to 8 hours. In this case, the abrasion resistance and strength of the honeycomb structure for the selective catalytic reduction catalyst can be further improved.

Hereinafter, the present invention will be described in detail through Examples and Comparative Examples. However, these are provided only to explain the present invention in detail, and the scope of the present invention is not limited thereto.

Example 1

After preparing 10 g of clay (MIZUKA-ACE #20, particle size 90 μm) as a silicon dioxide compound, it was dispersed in 100 g of water to prepare a dispersion. 100 g of metatitanic acid raw material (NANO Chemical, NMTA-01) was added to the dispersion, followed by stirring. The stirring was carried out by a propeller method for 1 hour at room temperature, and then the finished solution was washed twice with aqueous ammonia solution/filtered, and then distilled under reduced pressure to remove all solvents.

The solid content from which the solvent has been removed was put into a kiln at room temperature and heat-treated at 600° C. for 2 hours to prepare a silicon dioxide compound-supported titania carrier particle.

To 500 kg of the titania support particles, 500 kg of a catalytically active material (TiO ₂ ), 25 kg of an organic binder; After 50 kg of inorganic binder (clay and glass fiber) was added, a clay composition was prepared by kneading at 40°C to 60°C for 2 hours using a Kneader-mixer device. In the kneaded clay composition, 83 kg of titania support particles, 3 kg of catalytically active material, 3 kg of organic binder, and 10 kg of inorganic binder were included.

After measuring the moisture content and plasticity of the kneaded clay composition as described above, the honeycomb structure having an external size of 42 mm x 42 mm x 100 mm (width x length x length, thickness 0.6 mm) under constant speed conditions using a 1" molding extruder. Specimens were prepared.

Example 2

50 kg of a colloidal silica solution (40NH/130, particle size 22 μm) was prepared as a silicon dioxide compound, and 500 kg of the metatitanic acid raw material prepared in Preparation Example 1 was added and impregnated. The impregnation was carried out using a knead-mixer for 1 hour at room temperature, and then the finished dough was washed/filtered twice with aqueous ammonia solution, and then distilled under reduced pressure to remove all solvents. The solid content from which the solvent has been removed was put into a kiln at room temperature and heat-treated at 600° C. for 2 hours to prepare titania carrier particles on which the silicon dioxide compound was supported.

To 500 kg of the titania carrier particles, a catalytically active material (TiO ₂ 500 kg), 25 kg organic binder; After 50 kg of inorganic binder (clay and glass fiber) was added, the mixture was kneaded for 2 hours at 40°C to 60°C using a Kneader-mixer device.

After measuring the moisture content and plasticity of the clay composition kneaded as described above, under constant speed conditions using a 1" molding extruder, a honeycomb structure having an external size of 42 mm x 42 mm x 100 mm (width x length x length, thickness 0.6 mm) Specimens were prepared.

Comparative Example 1

It was prepared in the same manner as in Example 1, except that the weight ratio of the silicon dioxide compound and the raw metatitanic acid in the composition for preparing the carrier was changed to 1:6.

Comparative Example 2

It was prepared in the same manner as in Example 1, except that the weight ratio of the silicon dioxide compound and the raw metatitanic acid in the composition for preparing the carrier was changed to 1:8.

Comparative Example 3

It was prepared in the same manner as in Example 1, except that the weight ratio of the silicon dioxide compound and the raw metatitanic acid in the composition for preparing the carrier was changed to 1:12.

In Table 1 below, "weight ratio" is a weight ratio between the silicon dioxide compound and the metatitanic acid raw material.

Example 1 Example 2 Comparative Example 1 Comparative Example 2 Comparative Example 3 weight ratio 1:10 1:10 1:6 1:8 1:12 carrier crystalline phase anatase anatase anatase anatase anatase

<Evaluation of physical properties>

1. moisture content

After setting the zero point with an infrared moisture content measuring device (manufacturer KETT, product name FD-660), 5 g of a clay composition specimen was collected, heated at 150 ° C for 20 minutes, dried according to the setting value, and then the weight before and after moisture removal was measured. It was measured to measure the moisture content contained in the material. The results are shown in Table 2 below.

2. plasticity

5 g of the kneaded clay composition specimen was collected, and the plasticity was measured with a plasticity measuring device (manufacturer Askakiki, product name: Curd meter MAX ME-500). The results are shown in Table 2 below.

3. Extrusion Formability

After the extrusion was performed, the shape was visually evaluated. If cracks occurred or the shape was not maintained, it was evaluated as "unsuitable", and if no cracks were found at all, it was evaluated as "acceptable", and the results are shown in Table 2.

4. Visual inspection

The appearance inspection procedure was carried out based on the 'VGB guideline, which is the SCR catalyst guideline, and the inspection standard was conducted based on the SCR denitration catalyst technical specification for thermal power plants of Nano. All catalysts were first checked for crystals through visual inspection, and the occurrence of chips or cracks was determined using calipers. If a chip or crack was found, it was evaluated as "bad", and if it was not found at all, it was evaluated as "excellent", and the results are shown in Table 3.

5. Compressive strength

Compressive strength measurement was performed using Testmate's TM-UMS015T universal material tester, and a ceramic pad was applied to the surface to which the pressure is applied to keep the pressure supply balanced at a crosshead speed of 3 mm/min. did. The compressive strength evaluation was performed in the cross-wise direction and the length-wise direction, respectively. The results are shown in Table 3 below.

6. Wear rate and wear resistance

Using the catalyst wear resistance test apparatus described in Korean Patent Registration No. 10-1791332, the wear rate represented by the following Equation 1 was calculated. The results are shown in Table 3 below. Photos before and after the wear rate evaluation are shown in FIGS. 5 (Example 1) and 6 (Comparative Example 1), respectively. The wear resistance was evaluated as "unsuitable" when the wear rate exceeded 8%, and evaluated as "suitable" when the wear rate was 8% or less.

<Equation 1>

Wear rate (%) = {│( W ₀ - W ₁ )│ / W ₀ } × 100

In Equation 1, W ₀ is the mass measured before the abrasion test of the honeycomb structure specimen having an external size of 42 mm x 42 mm x 100 mm (width x length x length, thickness: 0.6 mm), and W ₁ is the specimen with a flow rate of 17 m / In s, the abrasive discharge amount is 25 kg/h, and it is the mass measured after a wear test for 30 minutes.

moisture content
(%) plasticity
(%) extrusion formability Example 1 29.4 36.2 Figure 1 fitness Example 2 28.3 37.3 - fitness Comparative Example 1 20.1 25.7 Figure 2 incongruity Comparative Example 2 21.5 27.5 Fig. 3 incongruity Comparative Example 3 23.2 26.1 Fig. 4 incongruity

Visual inspection result Cross-sectional compressive strength (kgf/cm ² ) Compressive strength in the longitudinal direction (kgf/cm ² ) wear rate
(%) wear resistance
Example 1 Great 17.5 36.2 4.5 fitness Example 2 Great 13.3 31.0 5.7 fitness Comparative Example 1 bad 10.5 28.3 10.5 incongruity Comparative Example 2 bad 10.1 26.7 8.2 incongruity Comparative Example 3 bad 12.5 29.7 9.7 incongruity

As can be seen from the results of Tables 2, 3 and 5, in the case of Examples 1 and 2 in which the nano silica compound was supported on the meta-titanic acid raw material, the compressive strength was remarkably excellent in the cross-sectional direction, and the abrasion resistance was suitable was confirmed.

On the other hand, as can be seen from the results of Tables 2, 3 and 6, when the weight ratio of the silicon dioxide compound and the raw metatitanic acid in the composition for preparing a carrier is out of the scope of the present invention, all the effects of the present invention can be obtained. It was confirmed that it cannot.

Simple modifications or changes of the present invention can be easily carried out by those of ordinary skill in the art, and all such modifications or changes can be considered to be included in the scope of the present invention.

Claims (10)

A composition for preparing a carrier comprising a silicon dioxide compound and a metatitanic acid ^{raw material having a packing density of 0.5 g/cm 3} to 0.7 g/cm ³ in a weight ratio of 1:9 to 1:11 is washed with ammonia water, filtered, and calcined. ,
A honeycomb structure for a selective catalytic reduction catalyst comprising titania support particles supported on a surface of silicon dioxide, wherein the support particles have an anatase-type titania crystal phase,
The silicon dioxide compound is a clay containing 98% or more of silicon dioxide,
The honeycomb structure for the selective catalytic reduction catalyst may include the support particles; catalytically active substances; organic binders; and an inorganic binder, wherein the honeycomb structure for a selective catalytic reduction catalyst is formed from a kneaded clay composition having a moisture content of 25% to 40%, and a plasticity of 30% to 50%.
According to claim 1,
The carrier particles are
1 wt% to 2 wt% of sulfur trioxide;
1 wt% to 5 wt% tungsten trioxide;
4% to 20% by weight of silicon dioxide; and
Which contains 75% to 90% by weight of titanium dioxide,
Honeycomb structure for selective catalytic reduction catalyst.
delete According to claim 1,
The selective catalytic reduction catalyst of a honeycomb structure, a honeycomb structure for selective catalytic reduction catalyst and the cross-sectional direction compressive strength of at least 13kgf / cm ^2, the longitudinal compressive strength of not less than 30kgf / cm ² for.
According to claim 1,
The honeycomb structure for the selective catalytic reduction catalyst has an abrasion rate of 9% or less, expressed by the following formula 1, of the honeycomb structure for a selective catalytic reduction catalyst:
<Equation 1>
Wear rate (%) = {│( W ₀ - W ₁ )│ / W ₀ } × 100
In Equation 1, W ₀ is the mass measured before the abrasion test of the honeycomb structure specimen having an external size of 42 mm x 42 mm x 100 mm (width x length x length, thickness: 0.6 mm), and W ₁ is the flow rate of the specimen. This is the mass measured after an abrasion test for 30 minutes at 17 m/s and an abrasive discharge rate of 25 kg/h.
By calcining a composition for preparing a carrier comprising a silicon dioxide compound and a metatitanic acid ^{raw material having a packing density of 0.5 g/cm 3} to 0.7 g/cm ³ in a weight ratio of 1:9 to 1:11, silicon dioxide is supported on the surface. preparing titania carrier particles;
preparing a clay composition by mixing and kneading a catalyst raw material, an organic binder, and an inorganic binder with the support particles; and
manufacturing a honeycomb structure by extruding the kneaded clay composition into a honeycomb shape, drying and calcining;
A method for producing a honeycomb structure for a selective catalytic reduction catalyst comprising:
The silicon dioxide compound is a clay containing 98% or more of silicon dioxide,
The step of preparing the carrier particles includes washing and filtering the composition for preparing the carrier with ammonia water and calcining,
The carrier particles have an anatase-type titania crystal phase,
The step of preparing the kneaded clay composition comprises adjusting the moisture content of the clay composition to 25% to 40% and plasticity to 30% to 50%, a method for producing a honeycomb structure for a selective catalytic reduction catalyst.
delete delete 7. The method of claim 6,
The carrier particles are
1 wt% to 2 wt% of sulfur trioxide;
1 wt% to 5 wt% tungsten trioxide;
4% to 20% by weight of silicon dioxide; and
Which contains 75% to 90% by weight of titanium dioxide,
A method for manufacturing a honeycomb structure for a selective catalytic reduction catalyst. delete

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