KR-102960951-B1 - HONEYCOMB SHAPE CATALYST FOR DECOMPOSITION OF PERFLUORINATED COMPOUNDS

KR102960951B1KR 102960951 B1KR102960951 B1KR 102960951B1KR-102960951-B1

Abstract

A honeycomb-shaped catalyst for decomposing perfluorinated compounds according to embodiments of the present invention comprises a body, a plurality of channels penetrating in a direction opposite to one side of the body, and a partition defining the channels, comprises aluminum oxide, and has a density of 300 g/L or more.

Inventors

김동우
김민지
지승환
정관형
안혜진
장하늘

Assignees

주식회사 에코프로에이치엔

Dates

Publication Date: 20260508
Application Date: 20250122
Priority Date: 20240221

Claims (14)

Body; A plurality of channels penetrating in a direction facing one side from one side of the body; and It includes a partition defining the above channels, It contains aluminum oxide as a catalyst, and A honeycomb-shaped catalyst for decomposing perfluorinated compounds having a density of 350 g/L to 1,100 g/L.
A honeycomb-shaped catalyst for decomposing perfluorinated compounds according to claim 1, wherein the density is 400 g/L to 1,000 g/L.
A honeycomb-shaped catalyst for decomposing perfluorinated compounds according to claim 1, wherein the number of channels per square inch (CPSI) of the catalyst is 30 to 150.
In claim 1, the catalyst further comprises pores, and A honeycomb-shaped catalyst for decomposing perfluorinated compounds, wherein the average diameter of the pores is 50 Å to 300 Å.
A honeycomb-shaped catalyst for decomposing perfluorinated compounds according to claim 4, wherein the volume of pores contained per unit mass of the catalyst is 0.2 cm³ /g to 0.6 cm³ /g.
A honeycomb-shaped catalyst for decomposing perfluorinated compounds according to claim 4, wherein the porosity of the catalyst according to the following formula 1 is 10 to 100: [Equation 1] Porosity = (PV/PD)× 10⁴ (In Equation 1, PV is the numerical value of the volume of pores contained per unit mass of the catalyst ( cm³ /g), and PD is the numerical value of the average diameter (Å) of the pores contained in the catalyst).
A honeycomb-shaped catalyst for decomposing perfluorinated compounds according to claim 1, wherein the surface area per unit mass of the catalyst is 40 m² /g or more.
A honeycomb-shaped catalyst for decomposing perfluorinated compounds according to claim 1, wherein the catalyst material distribution index according to the following formula 2 of the catalyst is 70 to 500: [Equation 2] Catalyst distribution index = {D×(L1/L2)}×100 In Equation 2, D is the numerical value of the density (kg/L) of the catalyst, L1 is the numerical value of the length (mm) of the channel of the catalyst, and L2 is the numerical value of the shortest distance (mm) between two adjacent channels of the catalyst.
A honeycomb-shaped catalyst for decomposing perfluorinated compounds according to claim 1, wherein the content of the aluminum oxide is 40% to 95% by weight of the total weight of the catalyst.
A honeycomb - shaped catalyst for decomposing perfluorinated compounds according to claim 1, wherein the aluminum oxide comprises one or more of alpha alumina (α- Al₂O₃ ), beta alumina (β- Al₂O₃ ), gamma alumina (γ- Al₂O₃ ), delta alumina (δ- Al₂O₃ ) , theta alumina (θ- Al₂O₃ ), and kappa alumina (κ- Al₂O₃ ) .
A honeycomb-shaped catalyst for decomposing perfluorinated compounds according to claim 1, wherein the strength reduction rate according to the following formula 3 is 45% or less: [Equation 3] Strength reduction rate (%) = 100 - [{1-(S E /S I )}×100] (In Equation 3, SE is the strength of the catalyst measured after passing a gas containing a perfluorinated compound for 300 hours, and SI is the strength of the catalyst measured without passing a gas containing a perfluorinated compound).
A honeycomb-shaped catalyst for decomposing perfluorinated compounds according to claim 1, wherein the surface area reduction rate according to the following formula 4 is 75% or less: [Equation 4] Surface area reduction rate (%) = 100 - [{1-(A E /A I )}×100] (In Equation 4, A E is the surface area of the catalyst measured after exposure to 950 °C for 4 hours, and A I is the surface area of the catalyst measured without exposure to heat).
A honeycomb-shaped catalyst assembly for decomposing perfluorinated compounds, wherein a plurality of honeycomb-shaped catalysts for decomposing perfluorinated compounds according to claim 1 are stacked and the channels of the catalysts are connected.
A step of preparing a honeycomb-shaped catalyst assembly for decomposing perfluorinated compounds according to claim 13; and A method for removing perfluorinated compounds, comprising the step of injecting a gas containing perfluorinated compounds into one side of the honeycomb-shaped catalyst assembly for decomposing perfluorinated compounds.

Description

Honeycomb-shaped catalyst for the decomposition of perfluorinated compounds The present invention relates to a honeycomb-shaped catalyst for decomposing perfluorinated compounds. Perfluorinated compounds (PFCs) are a type of organic fluorine compound that contains an excess amount of fluorine atoms (F). Functional groups of perfluorinated compounds may include halogens, carboxyl groups, oxy groups, sulfonic acid groups, etc. Examples of perfluorinated compounds include carbon tetrafluoride ( CF4 ), perfluoroheptanoic acid, and polytetrafluoroethylene (PTFE). Perfluorinated compounds can be used as etchants and cleaning agents in semiconductor manufacturing processes. Perfluorinated compounds have a high global warming potential and, due to their high stability and low decomposition rate, can remain in the surrounding environment and cause environmental pollution. Additionally, they can remain in the human body and cause diseases such as thyroid disorders, hormonal disorders, and diabetes. As the use of perfluorinated compounds increases due to factors such as the growing demand for semiconductors and environmental issues become more prominent, there is a growing demand for the decomposition of perfluorinated compounds. Catalytic decomposition is known as a method for decomposing perfluorinated compounds. For example, CF4 among perfluorinated compounds decomposes at high temperatures of 1,000°C or higher, but when using a catalyst, it can be decomposed at a temperature of about 700°C to 750°C. When a catalyst is exposed to perfluorinated compounds for a long period, damage to the surface structure may occur due to the adsorption/desorption of fluorine on the catalyst surface, which may lead to a decrease in the durability of the catalyst. In addition, when a catalyst is housed in a chamber and a gas containing perfluorinated compounds is passed through it, there are difficulties in long-term operation due to pressure loss caused by the pressure difference before and after permeation. Korean Patent Publication No. 10-2023-0083099 discloses a catalyst for decomposing perfluorinated compounds containing rare earth metals. However, considering energy efficiency, there is a need for a catalyst capable of decomposing perfluorinated compounds at a relatively low temperature. Additionally, there is a need for a catalyst with improved lifespan characteristics due to enhanced durability. FIGS. 1 and 2 are schematic diagrams showing a honeycomb-shaped structure of a honeycomb-shaped catalyst for decomposing perfluorinated compounds according to exemplary embodiments. FIG. 3 is a schematic diagram showing a reactor comprising a catalyst assembly according to exemplary embodiments. Hereinafter, the present disclosure will be described in detail with reference to the attached drawings. However, this is merely illustrative and the present disclosure is not limited to the specific embodiments described illustratively. Exemplary embodiments of the present invention provide a honeycomb-shaped catalyst for decomposing perfluorinated compounds (hereinafter referred to as "catalyst (100)") comprising aluminum oxide and having a density within a predetermined range. Additionally, a honeycomb-shaped catalyst assembly for decomposing perfluorinated compounds (hereinafter referred to as "catalyst assembly (200)") comprising the above-mentioned honeycomb-shaped catalysts for decomposing perfluorinated compounds is provided. Furthermore, a method for removing perfluorinated compounds using the above-mentioned catalyst is provided. The term "contact area" as used in the present invention may refer to an area controlled by the shape of the catalyst (100). For example, the contact area may be controlled by controlling the number of channels per square inch (CPSI). The term "surface area" used in the present invention may refer to an area controlled by pores included in the catalyst (100). For example, the surface area may be controlled by controlling the size, volume, number, etc. of the micropores included in the catalyst (100). FIGS. 1 and 2 are schematic diagrams showing the structure of a honeycomb-shaped catalyst for decomposing perfluorinated compounds according to exemplary embodiments. For example, FIG. 2 is a diagram showing the top surface of a honeycomb-shaped catalyst for decomposing perfluorinated compounds according to exemplary embodiments. In this specification, "height direction" may indicate the direction in which the channels are formed. For example, it may indicate the direction in which a gas containing a perfluorinated compound is permeated. For example, it may indicate a direction perpendicular to the x-axis direction and the y-axis direction of FIG. 2. Referring to FIG. 1, the catalyst (100) may have a honeycomb shape including a plurality of channels (105). For example, the catalyst (100) may include a body (101), a plurality of channels (105), and a partition (106) defining the channels (105). In one embodiment,