Hydrogen oxidation catalyst and method for producing the same

Abstract

The present invention provides a hydrogen oxidation catalyst, a hydrogen oxidation catalyst comprising a titanium dioxide support on which platinum clusters are supported, characterized in that the platinum clusters comprise Pt 0 , the Pt 0 constituting a terrace, a step, a kink crystal face, the terrace crystal face being more than the step, kink crystal face.

Description

Technical Field

[0001] This invention relates to a hydrogen oxidation catalyst and its preparation method, and more specifically, to a hydrogen oxidation catalyst and its preparation method that can control low concentrations of hydrogen under extremely low temperature and room temperature conditions. Background Technology

[0002] Currently, with increasing global attention on hydrogen energy, major countries such as the United States, Japan, and Europe are committed to the development of hydrogen energy technologies. Furthermore, continuous investment is being made in safety research regarding potential hydrogen leaks and explosions during the hydrogenation process. Specifically, hydrogen poses a risk of explosion due to its potential for spontaneous combustion in the surrounding environment at concentrations above 4 vol%, thus raising safety concerns related to hydrogen in various fields such as fuel cells, lead-acid batteries, and semiconductor processes.

[0003] Currently, research on hydrogen energy stability mainly focuses on hydrogen storage and cutoff, leak prevention sensors, etc., with recent research on hydrogen removal technology. Representative hydrogen removal technologies include igniters, thermal recombiners, or catalytic oxidation methods to prevent hydrogen explosion losses. Igniters and thermal recombiners control hydrogen by injecting heat energy to the reaction temperature at which hydrogen can recombine into water; however, they have drawbacks such as limited space requirements and the need for additional energy sources.

[0004] In contrast, catalytic oxidation technology removes hydrogen by using a catalyst to combine gaseous oxygen and hydrogen, and it is a technology that can safely control hydrogen. Therefore, among the three methods mentioned above, catalytic oxidation technology, which uses a catalyst to combine hydrogen and oxygen, has attracted the most attention.

[0005] This catalytic oxidation technology does not require additional energy and can recover the heat generated by the exothermic reaction of hydrogen and oxygen, making it suitable for heating or hot water supply, or as a source of thermal energy for the system, thus offering advantages in energy efficiency. Furthermore, it has the advantage of utilizing natural convection caused by the heat generated from processing hydrogen produced in a confined space for continuous processing. Relatedly, Patent No. 10-0998325 relates to a catalyst preparation technique for oxidizing formaldehyde at room temperature using a platinum / titanium dioxide catalyst; Patent No. 10-1660014 relates to platinum-based catalysts, specifically a platinum / titanium dioxide catalyst capable of removing hydrogen at room temperature; and Patent No. 10-1331391 relates to a palladium / titanium dioxide catalyst (not a platinum / titanium dioxide catalyst) and its manufacturing method, disclosing a palladium / titanium dioxide catalyst capable of removing formaldehyde, carbon monoxide, and hydrogen contained in room temperature air, and its manufacturing method.

[0006] Thus, the prior art discloses a catalyst that can remove hydrogen at room temperature, but in fact does not disclose a catalyst that can remove low concentrations of hydrogen at extremely low temperatures. Summary of the Invention

[0007] Technical issues

[0008] Therefore, the present invention aims to solve the above-mentioned problems arising in the prior art, and the object of the present invention is to provide a hydrogen oxidation catalyst capable of removing hydrogen at non-room temperature, low temperature and low concentration.

[0009] Technical solution

[0010] According to one aspect of the present invention, a hydrogen oxidation catalyst is provided, comprising a titanium dioxide support loaded with platinum clusters, wherein the platinum clusters contain Pt. 0 The Pt 0 It includes terrace, step, and kink crystal surfaces, with more terrace crystal surfaces than step and kink crystal surfaces.

[0011] In one embodiment of the present invention, the oxidation ratio of the platinum cluster (Pt) 0 / Pt total It can be 40% to 50%.

[0012] In one embodiment of the present invention, the hydrogen oxidation catalyst can exhibit hydrogen oxidation activity at extremely low temperatures (-10°C) within a temperature range of 25°C.

[0013] In one embodiment of the present invention, the titanium dioxide support may also be loaded with one or more cocatalysts selected from palladium and antimony.

[0014] In one embodiment of the present invention, the hydrogen oxidation catalyst can also have a hydrogenation activity of more than 95% under the condition of simultaneous injection of helium oxide.

[0015] In one embodiment of the present invention, the hydrogen oxidation catalyst can also have more than 80% hydrogenation activity when carbon monoxide is injected simultaneously.

[0016] According to another aspect of the present invention, a method for preparing a hydrogen oxidation catalyst is provided, the method comprising: loading a platinum cluster precursor onto a titanium dioxide support; and calcining the loaded platinum cluster / titanium dioxide at 200–300 °C, wherein the platinum cluster comprises Pt. 0 The Pt 0It includes terrace, step, and kink crystal planes, and within the calcination temperature range, the terrace crystal planes are more numerous than the step and kink crystal planes.

[0017] In one embodiment of the present invention, the platinum cluster precursor may be 0.5 parts by weight or more relative to 100 parts by weight of titanium dioxide carrier.

[0018] In one embodiment of the present invention, the platinum cluster precursor can be one of Ptc(MA), Ptc(EN), and Ptc(EA).

[0019] As an embodiment of the present invention, in the calcination step, the oxidation ratio of the reduced platinum clusters (Pt) is... 0 / Pt total It can be 40% to 50%.

[0020] In one embodiment of the present invention, the method may further include loading a cocatalyst precursor comprising one or more of palladium and antimony onto the titanium dioxide support before loading the platinum cluster precursor onto the titanium dioxide support.

[0021] In one embodiment of the present invention, the above-mentioned cocatalyst precursor may be 0.1 to 2.0 parts by weight relative to 100 parts by weight of titanium dioxide support.

[0022] Invention Effects

[0023] The hydrogen oxidation catalyst according to the present invention can effectively control low concentrations of hydrogen not only at room temperature, but also at extremely low temperatures.

[0024] Furthermore, since there is no need for a reduction process using a hydrogen oxidation catalyst, Pt can be produced solely through a firing process. 0 This species can reduce manufacturing time and costs. Attached Figure Description

[0025] Figure 1 shows Pt 0 A diagram of the reaction crystallization plane.

[0026] Figures 2 and 3 show the activity of the hydroxide reaction based on the hydrogen concentration of the Pt precursor and the reaction temperature, respectively.

[0027] Figure 4 shows the FT-IR analysis results of the adsorption characteristics of the Pt precursor.

[0028] Figure 5 is a graph showing the hydrogen reactivity based on the sintering temperature.

[0029] Figure 6 shows the FT-IR analysis results of the adsorption characteristics based on the calcination temperature.

[0030] Figure 7 shows the hydroxide activity diagrams for different Ptc contents;

[0031] Figures 8 and 9 show the hydrogen reaction activity based on the addition of a co-catalyst, respectively.

[0032] Figures 10 and 11 show the hydrogen reactivity based on the amount of co-catalyst added.

[0033] Figures 12, 13, and 14 show the hydrogen reactivity when carbon monoxide and hydrogen of different concentrations flow in simultaneously.

[0034] Figures 15, 16, and 17 show the hydrogen reactivity when helium oxide and hydrogen flow in simultaneously at different concentrations.

[0035] Figure 18 is a graph showing the hydrogen reaction activity at different reaction temperatures depending on the addition of a co-catalyst.

[0036] Figure 19 is a graph showing the selective reactivity with respect to hydrogen and carbon monoxide. Detailed Implementation

[0037] Because this disclosure allows for various modifications and numerous embodiments, specific embodiments will be shown in the accompanying drawings and described in detail in the written description. However, this is not intended to limit the invention to the specific embodiments, and it should be understood that all modifications, equivalents, and substitutions that do not depart from the spirit and scope of the invention are included within its scope. In describing the invention, detailed descriptions of relevant prior art are omitted where it is determined that such descriptions might obscure the essence of the invention.

[0038] Figure 1 shows Pt 0 A diagram of the reaction crystallization plane.

[0039] Referring to Figure 1, Pt 0 It possesses a stepped crystal structure, forming three reactive crystal faces as the atoms grow. When the stepped crystal structure is observed three-dimensionally, the flat surfaces that appear planar are called terrace surfaces, the corner surfaces between the terrace surfaces that appear as steps are called step surfaces, and the apex surfaces of the step surfaces that are cut off or appear curved are called kink surfaces. At this point, the step and kink surfaces are highly reactive, thus easily dissociating and adsorbing, while the terrace surface is less reactive, thus exhibiting the characteristic of direct molecular adsorption compared to dissociation and adsorption. Furthermore, as a result of FT-IR (Fourier transform-infrared) analysis, the terrace surface shows a wavenumber (cm²) range of 2075–2100. -1The step surface is displayed as 2050–2075 wavenumbers (cm). -1 The crack (Kink) surface shows a wavenumber (cm) of 2000–2050. -1 Each reaction crystal plane can be defined. The three reaction crystal planes mentioned above exhibit different adsorption properties due to the different arrangements of atoms, and their activity in the hydroxide reaction varies depending on the degree of growth of each reaction crystal plane, which will be explained in detail in the experimental examples described later.

[0040] In this specification, "platinum cluster (Ptc)" refers to Pt residues that remain after calcination and are supported on a catalyst support. 0 The platinum structure means that Pt 0 In the reaction crystallization plane, the terrace plane dominates all platinum structures. At this point, the reaction crystallization plane associated with the hydroxide reaction is Pt. 0 The reaction crystal plane, rather than the overall Pt representing various oxidation states.

[0041] Furthermore, in this specification, "Pt" 0 The dominant existence of terrace surfaces means that due to Pt 0 The growth of terrace surfaces in the reaction crystallization plane is maximized. There are more terrace surfaces than step and kink surfaces. Therefore, during the hydrogen oxidation reaction, the proportion of terrace surfaces that adsorb hydrogen as reaction crystallization planes is higher than the sum of the proportions of step and kink surfaces.

[0042] This invention provides a hydrogen oxidation catalyst comprising a titanium dioxide support with platinum clusters, which removes low concentrations of hydrogen not only at room temperature but also at extremely low temperatures, wherein the platinum clusters contain Pt. 0 The Pt 0 It includes terrace, step, and kink crystal surfaces, with more terrace crystal surfaces than step and kink crystal surfaces.

[0043] In particular, unlike previous technologies that used PtCl4 and Pt(OH)2 as platinum precursors to remove hydrogen only at room temperature, the hydrogen oxidation catalyst of this invention, which uses a platinum cluster-supported catalyst, can remove hydrogen not only at room temperature (25°C) but also at extremely low temperatures (-10°C). The following experimental examples illustrate in detail the hydrogen removal effect at both room temperature and extremely low temperatures with the use of platinum clusters.

[0044] Platinum clusters, equivalent to active metals, can be used on the surface of hydrogen oxidation catalysts in the form of Pt. 0 or Pt 2+ Oxidation to species, Pt 0 This corresponds to the main factor in the reactivity of the hydroxide reaction. In one embodiment of the invention, the oxidation ratio of the platinum cluster (Pt) 0 / Pt total It can be 40% to 50%.

[0045] As described above, the aforementioned Pt 0 Different reaction crystal surfaces, such as terraces, steps, and kinks, are formed based on the arrangement of atoms on the crystal surface. Different arrangements of atoms on these crystal surfaces result in different adsorption properties. In existing technology using Pt(OH)₂ as a platinum precursor, it only exhibits hydrogen adsorption properties at room temperature. At this temperature, Pt… 0 The crystal planes are mainly Step and Kink planes, with the Step plane having a particularly high proportion. In contrast, this invention using platinum clusters not only exhibits low-concentration hydrogen adsorption properties at room temperature, but also... 0 The crystallographic planes of Pt mainly exhibit terrace surfaces. That is, during the hydrogen adsorption process, Pt... 0w When there are more Terrace surfaces than Step and Kink surfaces, low concentrations of hydrogen can be controlled not only at room temperature but also at ultra-low temperatures.

[0046] The aforementioned titanium dioxide support can be further loaded with one or more co-catalysts, namely palladium and antimony. With the addition of co-catalysts, the hydrogen oxidation activity at extremely low temperatures is improved, and the resistance to poisoning caused by the simultaneous inflow of carbon monoxide and helium oxides is enhanced. This effect is described in detail in the experimental examples described later.

[0047] Furthermore, the present invention provides a method for preparing a hydrogen oxidation catalyst, the method comprising the steps of loading a platinum cluster precursor onto a titanium dioxide support and calcining the titanium dioxide support loaded with the platinum cluster precursor.

[0048] The aforementioned platinum cluster precursor can be one of Ptc(MA), Ptc(EN), and Ptc(EA), but Ptc(MA) is preferred when considering high specific surface area and active particle size. In Ptc(MA), Ptc(EN), and Ptc(EA), MA represents methanol, EN represents nitric acid, and EA represents ethanol, and the platinum cluster precursor is prepared by processing each material.

[0049] Based on 100 parts by weight of titanium dioxide scaffold, preferably with a platinum cluster precursor loading of 0.5 parts by weight or more, within this range, not only can low concentrations of hydrogen present at room temperature be removed, but also low concentrations of hydrogen present at extremely low temperatures can be removed.

[0050] In particular, the present invention can represent Pt by calcining a titanium dioxide support loaded with a platinum cluster precursor. 0 The oxidation of PtCl4 and Pt(OH)2 is required when preparing hydrogen oxidation catalysts using conventional platinum precursors. This requires a reduction process following the calcination of the catalyst to represent the oxidation of Pt. 0 In contrast, this invention, by using a platinum cluster precursor, can represent Pt through a single sintering process. 0 Because of this species, the cost and time of preparation processes can be reduced.

[0051] During calcination, the oxidation ratio of the reduced platinum cluster precursor (Pt) 0 / Pt tota1 The concentration can be 40% to 50%, and within this range, low concentrations of hydrogen can be controlled not only at room temperature but also at ultra-low temperatures.

[0052] The preferred calcination temperature during the calcination process is 200–300°C. Within this range, Pt 0 The oxidation process can maintain the aforementioned ratio range of the paper, with the Terrace surface dominating, thus allowing control of low hydrogen concentrations at ultra-low temperatures. Beyond this range, the catalyst specific surface area decreases significantly, and Pt... 2+ Maximize growth, thereby not only reducing Pt 0 The proportion, and due to Pt 0 The growth of the Step and Kink surfaces reduces the proportion of the Terrace surface, thereby decreasing the activity of low-concentration hydroxides at extremely low temperatures.

[0053] In an exemplary embodiment of the present invention, before loading the platinum cluster precursor onto the titanium dioxide support, the step of loading a cocatalyst precursor containing one or more of palladium and antimony onto the titanium dioxide support may be included.

[0054] The aforementioned cocatalyst precursor can improve the hydrogenation activity under extremely low temperature conditions and enhance the resistance to toxicity caused by the simultaneous inflow of carbon monoxide and helium oxide. Preferably, 0.1 to 2.0 parts by weight of the aforementioned cocatalyst precursor are loaded relative to 100 parts by weight of titanium dioxide support.

[0055] The present invention will now be described in more detail based on preferred experimental examples. However, the technical concept of the present invention is not limited thereto, and can certainly be implemented in various ways by those skilled in the art.

[0056]

Example

[0057] Experimental Example 1: Comparison of hydrogen reactivity

[0058] Figures 2 and 3 show the activity of the hydroxide reaction based on the hydrogen concentration of the Pt precursor and the reaction temperature, respectively.

[0059] Referring to Figure 2, the hydrogen oxidation activity of the catalyst prepared by Ptc(MA) remains at 100% even in low concentrations of hydrogen. In contrast, the hydrogen oxidation activity of the catalyst prepared by PtCI4 and Pt(OH)2 is significantly reduced in low concentrations of hydrogen.

[0060] Furthermore, as shown in Figure 3, the catalyst made of Ptc(MA) maintains high hydrogen hydration activity not only at room temperature (25°C) but also at extremely low temperatures (-10°C), while the catalysts made of PtCl4 and Pt(OH)2 show almost no hydrogen hydration activity at extremely low temperatures.

[0061] In other words, the hydrogen oxidation catalyst according to the present invention is expected to enable low-concentration hydrogen control not only at room temperature but also at ultra-low temperatures.

[0062] Experimental Example 2: Comparison of Oxidation States and Physical Properties of Pt Precursors

[0063] Table 1 shows the oxidation state and physical properties of each Pt precursor.

[0064] [Table 1]

[0065]

[0066]

[0067] Referring to Table 1, Ptc(MA) has approximately 4.5 times the specific surface area compared to PtCl4 and approximately 3.6 times the specific surface area compared to Pt(OH)2. The reaction particle size is 4.85 nm, and the lattice oxygen (0 α The proportion of [missing information] is also high. Therefore, regarding Experimental Example 1, the aforementioned superior characteristics are considered to contribute to the high activity of the hydrogenation reaction of the platinum cluster-supported catalyst according to the present invention.

[0068] Experimental Example 3: Comparison of the adsorption characteristics of Pt precursors Figure 4 shows the FT-IR analysis results representing the adsorption characteristics of the Pt precursor, and Table 2 shows the FT-IR analysis results.

[0069] [Table 2]

[0070]

[0071] Referring to Figure 4 and Table 2, it can be confirmed that Ptc(MA) changes with Pt 0 The Pt(OH)2 grows on the terrace surface, where adsorption actively occurs, and Pt(OH)2 follows the growth of Pt. 0The Pt catalyst grows on a step and kink surface, with adsorption mainly occurring on the step surface. That is, in the hydrogen oxidation catalyst of this invention... 0 The plateau surface is dominant, and hydrogen adsorption occurs actively on this plateau surface, allowing for low-concentration hydrogen control not only at room temperature but also at low temperatures.

[0072] Experimental Example 4: Comparison of hydrogen reactivity, physical properties, and oxidation state based on calcination temperature

[0073] Figure 5 and Table 3 show the results of hydrogen reactivity, physical properties, and oxidation state at different calcination temperatures of the present invention.

[0074] [Table 3]

[0075]

[0076] Referring to Figure 5 and Table 3, it can be confirmed that, under firing conditions of 200℃ and 300℃, Pt 0 The platinum cluster-supported hydrogen oxidation catalyst exhibits a high specific surface area and small particle size. However, when calcined at temperatures above 300°C, the specific surface area decreases dramatically, and the particle size increases. Most importantly, it can be confirmed that calcination at 200°C and 300°C demonstrates high hydrogen reactivity not only at room temperature but also at extremely low temperatures (-10°C). However, calcination at temperatures above 300°C results in a gradual decrease in hydrogen reactivity at room temperature, and almost no hydrogen reactivity at extremely low temperatures (-10°C). Therefore, it can be determined that calcination at 200-300°C results in high hydrogen control performance at extremely low temperatures and low concentrations.

[0077] Experimental Example 5: Comparison of Adsorption Characteristics Based on Firing Temperature

[0078] Figure 6 is a graph showing the FT-IR analysis results of the adsorption characteristics of the present invention according to the sintering temperature, and Table 4 is a table showing the FT-IR analysis results.

[0079] [Table 4]

[0080] Firing temperature (°C) Kink Step Terrace <![CDATA[FT-IR wavenumber(cm -1 )]]> 2000～2050 2050～2075 2075～2100 200 4.61 37.1 58.29 300 2.83 11.7 85.2 400 8.1 20.1 71.8 500 9.7 26.1 64.2 600 12.7 57.2 31.1

[0081] Referring to Figure 6 and Table 4, in this invention, Pt 0The plateau surface exhibits dominance, particularly when calcined at 300°C, where its specific gravity reaches a maximum of 85.2%. However, when calcined at temperatures above 300°C, the specific gravity of the plateau surface decreases. Therefore, the platinum cluster-supported hydrogen oxidation catalyst, when calcined at 300°C, promotes plateau surface growth, indicating excellent control performance for low-concentration hydrogen not only at room temperature but also at extremely low temperatures.

[0082] Experimental Example 6: Comparison of Hydrogenation Activity Based on Ptc Content

[0083] Figure 7 is a graph showing the hydroxide activity of the present invention with different positive temperature coefficient contents.

[0084] Referring to Figure 7, it can be confirmed that as the Ptc content increases, at extremely low temperatures (-

[0085] Hydrogen hydroxide activity increases at 10°C, and the minimum Ptc content required to exhibit hydrogen hydroxide activity at extremely low temperatures is 0.1%. That is, it can be confirmed that in order to control low concentrations of hydrogen at extremely low temperatures, the Ptc content should be at least 0.1 parts by weight relative to 100 parts by weight of titanium dioxide support.

[0086] Experimental Example 7: Comparison of hydrogen reactivity based on the addition of a co-catalyst

[0087] Figures 8 and 9 show the hydrogen reaction activity based on the addition of a co-catalyst, respectively.

[0088] Referring to Figure 8, when Pd and Sb are added as co-catalysts, at extremely low temperatures (-

[0089] The hydrogen reactivity is high at -10°C, but somewhat lower at extremely low temperatures without the addition of a co-catalyst. Furthermore, referring to Figure 9, Ptc(MA) and Pt(OH)₂, with the same co-catalyst, exhibit very large differences in hydrogen reactivity at ultra-low temperatures. Therefore, it can be confirmed that by adding Pd or Sb co-catalysts to the hydrogen oxidation catalyst supported on the platinum clusters of this invention, the reactivity of low-concentration hydrogen can be improved at extremely low temperatures (-10°C).

[0090] Experimental Example 8: Comparison of hydrogen reactivity based on co-catalyst content

[0091] Figures 10 and 11 are graphs showing the hydrogen reactivity depending on the amount of Pd and Sb added, respectively.

[0092] Referring to Figures 10 and 11, as the Pd content increases from 0.1 to 0.5, the reactivity for low-concentration hydrogen at extremely low temperatures (-10°C) improves. Similarly, as the Sb content increases from 1.0 to 2.0, the reactivity for low-concentration hydrogen at extremely low temperatures also improves, but when the content exceeds 2.0, the reactivity for hydrogen slightly decreases. Therefore, it can be confirmed that, based on 100 parts by weight of titanium dioxide support, only the addition of 0.1 to 2.0 parts by weight of a co-catalyst results in excellent reactivity for low-concentration hydrogen at extremely low temperatures.

[0093] Experimental Example 9: Comparison of carbon monoxide endothelial toxicity based on the addition of co-catalysts

[0094] Figures 12, 13, and 14 show the hydrogen reactivity when carbon monoxide and hydrogen of different concentrations flow in simultaneously.

[0095] Referring to Figures 12 and 13, it can be confirmed that at a reaction temperature of -10℃ to 25℃, when carbon monoxide and hydrogen at a concentration of 2.5 ppm or 5.0 ppm flow in simultaneously, the hydrogen reactivity with resistance to toxicity is higher when Pd or Sb is added as a co-catalyst compared to the case without the addition of a co-catalyst. In particular, when Pd is added as a co-catalyst, the hydrogen reactivity with high resistance to carbon monoxide toxicity remains high.

[0096] Furthermore, referring to Figure 14, at a reaction temperature of 50°C, when 5.0 ppm of carbon monoxide and hydrogen flow in simultaneously, if Pd is added as a co-catalyst, it exhibits nearly 100% hydrogen reactivity, thus showing very high carbon monoxide endothelial toxicity. However, the hydrogen reactivity of Pt(OH)2 decreases sharply, thus showing very low carbon monoxide endothelial toxicity.

[0097] Experimental Example 10: Comparison of Helium Oxide Endothelial Toxicity Based on the Addition of Co-catalysts

[0098] Figures 15, 16, and 17 show the hydrogen reactivity when helium oxide and hydrogen flow in simultaneously at different concentrations.

[0099] Referring to Figures 15 and 16, at reaction temperatures ranging from -10°C to 25°C, when helium oxide at concentrations of 2.5 ppm or 5.0 ppm is simultaneously introduced along with hydrogen, the addition of Pd or Sb as a co-catalyst demonstrates resistance to helium oxide toxicity. Therefore, the hydrogen reactivity is higher than in the case without a co-catalyst. Particularly with the addition of Pd as a co-catalyst, high resistance to helium oxide toxicity is confirmed, thus maintaining high hydrogen reactivity. Furthermore, compared to Experimental Example 9, it is confirmed that the increase in skin toxicity resistance caused by the addition of a co-catalyst is greater for helium oxide than for carbon monoxide.

[0100] Furthermore, referring to Figure 17, at a reaction temperature of 50°C, when 5.0 ppm of helium oxide and hydrogen flow in simultaneously, Pd, when added as a co-catalyst, exhibits nearly 100% hydrogen reactivity, thus demonstrating that helium oxide has very high endothelial toxicity. However, the hydrogen reactivity of Pt(OH)2 decreases sharply, thus demonstrating that helium oxide has very low endothelial toxicity.

[0101] Experimental Example 11: Comparison of hydrogen reactivity at different reaction temperatures with added co-catalysts

[0102] Figure 18 is a graph showing the hydrogen reaction activity at different reaction temperatures depending on the addition of a co-catalyst.

[0103] Referring to Figure 18, it can be confirmed that Pt(OH)2 without the addition of a cocatalyst only exhibits hydrogen reactivity at 50°C, and especially at extremely low temperatures (-10°C) it shows almost no hydrogen reactivity. In contrast, Ptc(MA) with Pd added as a cocatalyst exhibits high hydrogen reactivity over a wide temperature range of -10°C to 50°C.

[0104] Experimental Example 12: Comparison of the selective reactivity of hydrogen and carbon monoxide

[0105] Figure 19 is a graph showing the selective reactivity with respect to hydrogen and carbon monoxide.

[0106] Referring to FIG19, it can be confirmed that in the case of the addition of Ptc or Ptc co-catalyst in the present invention, the reactivity with hydrogen is high even when hydrogen and carbon monoxide coexist, thus enabling selective control of hydrogen. In contrast, Pt(OH)2 only exhibits reactivity with carbon monoxide, thus making it difficult to control hydrogen.

Claims

1. A hydrogen oxidation catalyst comprising a titanium dioxide support loaded with platinum clusters, characterized in that, The platinum cluster contains Pt 0 The Pt 0 It includes terrace, step, and kink crystal planes, wherein the number of terrace crystal planes exceeds the number of step and kink crystal planes, and Pt 0 / ( Pt 0 +Pt 2+ = 40~50%; The method for preparing the hydrogen oxidation catalyst includes: The platinum cluster precursor is loaded onto the titanium dioxide support, wherein the platinum cluster precursor is selected from Ptc(MA), Ptc(EN), and Ptc(EA), wherein Ptc(MA) is a methanol-treated platinum cluster precursor, Ptc(EN) is a nitric acid-treated platinum cluster precursor, and Ptc(EA) is an ethanol-treated platinum cluster precursor, and the platinum cluster precursor is 0.5 to 5 parts by weight relative to 100 parts by weight of the titanium dioxide support; and The platinum cluster / titanium dioxide was calcined at 200~300°C.

2. The hydrogen oxidation catalyst according to claim 1, characterized in that, The hydrogen oxidation catalyst exhibits hydrogen oxidation activity at temperatures ranging from -10°C to 25°C.

3. The hydrogen oxidation catalyst according to claim 1, characterized in that, The titanium dioxide support also contains one or more co-catalysts selected from palladium and antimony.

4. The hydrogen oxidation catalyst according to claim 3, characterized in that, The hydrogen oxidation catalyst also has a hydrogen conversion rate of over 95% under the condition of simultaneous injection of nitrogen oxides.

5. The hydrogen oxidation catalyst according to claim 3, characterized in that, The hydrogen oxidation catalyst also has a hydrogen conversion rate of over 80% under the condition of simultaneous injection of carbon monoxide.

6. A method for preparing a hydrogen oxidation catalyst, characterized in that, Include: A platinum cluster precursor is loaded onto a titanium dioxide support, wherein the platinum cluster precursor is selected from Ptc(MA), Ptc(EN), and Ptc(EA), wherein Ptc(MA) is a methanol-treated platinum cluster precursor, Ptc(EN) is a nitric acid-treated platinum cluster precursor, and Ptc(EA) is an ethanol-treated platinum cluster precursor, and the amount of the platinum cluster precursor is 0.5 to 5 parts by weight relative to 100 parts by weight of the titanium dioxide support; and The supported platinum cluster precursor / titanium dioxide was calcined at 200-300°C to obtain a platinum cluster-supported titanium dioxide carrier for hydrogen oxidation catalyst, wherein the platinum cluster contains Pt. 0 And Pt 0 / ( Pt 0 +Pt 2+ ) = 40~50%, the Pt 0 It includes terrace, step, and kink crystal planes, and within the calcination temperature range, the number of terrace crystal planes exceeds the number of step and kink crystal planes.

7. The method for preparing the hydrogen oxidation catalyst according to claim 6, characterized in that, Before loading the platinum cluster precursor onto the titanium dioxide support, the method further includes the step of loading a cocatalyst precursor comprising one or more of palladium and antimony onto the titanium dioxide support.

8. The method for preparing the hydrogen oxidation catalyst according to claim 6, characterized in that, The cocatalyst precursor is 0.1 to 2.0 parts by weight relative to 100 parts by weight of titanium dioxide support.

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