KR102312917B1 - Catalyst compound and combustion device comprising thereof - Google Patents

Abstract

According to an embodiment of the present invention, an activated carbon substrate; and an acid site provided on the activated carbon substrate, wherein the acid site includes a Bronsted acid site and a Lewis acid site, and the ratio of the Bronsted acid site to the Lewis acid site is 1.3 to 1.6 Phosphorus, a catalyst compound is provided.

Description

CATALYST COMPOUND AND COMBUSTION DEVICE COMPRISING THEREOF

The present invention relates to a catalyst compound and a combustion device comprising the catalyst compound.

Recently, with the development of aircraft technology, more and more aircraft are operating at a higher speed than before. One of the essential techniques to secure a strong driving force is to remove heat. This is because, when an aircraft gains strong propulsion and moves quickly, frictional heat due to friction between the aircraft and air and combustion heat due to fuel combustion are generated very much. If not properly removed, this heat can cause deformation of the components that make up the aircraft, which can cause the aircraft to malfunction.

In order to remove heat, various heat dissipating members are provided on the aircraft. For example, heat dissipation panels with high thermal conductivity, cooling piping, etc. are provided to remove combustion heat. However, due to the characteristics of the aircraft, the internal space is limited and the weight of the aircraft must be reduced. Therefore, it is very difficult to provide an excellent heat dissipation effect while satisfying these limitations.

An effective heat dissipation method used recently is to use an endothermic fuel. The endothermic fuel can be decomposed into low molecular weight substances before combustion. The decomposition reaction of the endothermic fuel is an endothermic reaction that absorbs heat. Accordingly, while the heat generated in the aircraft is used as the reaction heat of the endothermic fuel decomposition reaction, a heat dissipation effect can be provided.

Heat dissipation using such an endothermic fuel is very advantageous because it does not significantly increase the weight or increase the volume of the aircraft in terms of using the fuel used for the aircraft. However, in order to provide the heat dissipation effect using the endothermic fuel, the endothermic fuel decomposition reaction must proceed smoothly. Therefore, there is a need for an excellent catalyst compound capable of promoting the endothermic fuel decomposition reaction.

An object of the present invention is to provide a combustion device that includes a catalyst compound capable of promoting the decomposition reaction of an endothermic fuel and a catalyst compound, which promotes an endothermic fuel decomposition reaction, and thus has excellent heat dissipation performance.

According to an embodiment of the present invention, an activated carbon substrate; and an acid site provided on the activated carbon substrate, wherein the acid site includes a Bronsted acid site and a Lewis acid site, and the ratio of the Bronsted acid site to the Lewis acid site is 1.3 to 1.6 Phosphorus, a catalyst compound is provided.

According to an embodiment of the present invention, the acid site comprises at least one of a weak acid site, a medium acid site, and a strong acid site, wherein the steel on the activated carbon substrate is The catalyst compound is provided, wherein the density of acid sites is from 0.5 mmol-NH3/g to 1.8 mol-NH3/g.

According to an embodiment of the present invention, the catalyst compound has at least one or more pores, the pores include mesopores and micropores, and the micropores are pores having an average diameter of about 2 nm or less. A catalyst compound is provided, wherein the mesopores are pores other than micropores.

According to an embodiment of the present invention, the volume of the mesopores is 0.4 cm ³ g ^-1 to 0.6 cm ³ g ^-1 , the catalyst compound is provided.

According to one embodiment of the present invention, the average diameter of the pores is 4.5nm to 6.0nm, the catalyst compound is provided.

According to an embodiment of the present invention, the Bronsted acid site promotes the conversion of an aliphatic hydrocarbon compound to a carbonium ion (Carbonium Ion), a catalyst compound is provided.

According to one embodiment of the present invention, the catalyst compound has a specific surface area of 560 m ² g ^-1 to 780 m ² g ^-1 , the catalyst compound is provided.

According to an embodiment of the present invention, a combustion chamber for burning the fuel supplied from the fuel pipe is provided, a catalyst layer is provided on one surface of the fuel pipe, and the catalyst layer is an activated carbon substrate; and an acid site provided on the activated carbon substrate, wherein the acid site includes a Bronsted acid site and a Lewis acid site, and the ratio of the Bronsted acid site to the Lewis acid site is 1.3 to 1.6 A combustion device comprising phosphorus, a catalyst compound is provided.

According to an embodiment of the present invention, the catalyst compound decomposes hydrocarbons contained in the fuel into hydrocarbons having a lower molecular weight, a combustion device is provided.

According to an embodiment of the present invention, there is provided a combustion device, wherein the decomposition of hydrocarbons by the catalyst compound is an endothermic reaction, and the catalyst layer absorbs heat generated from the combustion chamber.

According to an embodiment of the present invention, a catalyst compound capable of promoting an endothermic fuel decomposition reaction is provided.

In addition, according to an embodiment of the present invention, an endothermic fuel decomposition reaction is promoted by including a catalyst compound, and thus a combustion device having excellent heat dissipation performance is provided.

1 is a cross-sectional view showing a combustion device according to an embodiment of the present invention.
2A and 2B are graphs showing compositions of catalyst compounds according to an embodiment and a comparative example of the present invention.
3 is a graph showing the composition of a catalyst compound according to an embodiment and a comparative example of the present invention.
4 is a graph showing the composition of a catalyst compound according to an embodiment and a comparative example of the present invention.
5 is a graph showing the composition of a catalyst compound according to an embodiment and a comparative example of the present invention.
6 is a graph showing the activity of a catalyst compound according to an embodiment and a comparative example of the present invention.
7 is a graph showing the activity of a catalyst compound according to an embodiment and a comparative example of the present invention.
8 is a graph showing the activity of a catalyst compound according to an embodiment and a comparative example of the present invention.

Since the present invention can have various changes and can have various forms, specific embodiments are illustrated in the drawings and described in detail in the text. However, this is not intended to limit the present invention to the specific disclosed form, it should be understood to include all modifications, equivalents and substitutes included in the spirit and scope of the present invention.

According to an embodiment of the present invention, a catalyst compound for accelerating a fuel cracking reaction is provided. Since the fuel cracking reaction promoted by the catalyst compound is an endothermic reaction, ambient heat can be removed when the fuel cracking reaction is performed.

The catalyst compound comprises an activated carbon substrate and an acid site provided on the activated carbon substrate.

As the activated carbon substrate, those obtained from various sources may be used. For example, bituminous coal-derived activated carbon, petroleum pitch-derived activated carbon, or the like may be used as the activated carbon substrate.

The activated carbon substrate may include at least one or more pores. The pores may be provided in the form of pores having one surface of the activated carbon substrate open, and may have various shapes and various sizes. The aforementioned pores may include mesopores and micropores. Mesopores may mean pores having a diameter of about 2 nm or more, and micropores may mean pores having a diameter of about 2 nm or less. In this case, the diameter of the pore means the average diameter of the pore, and when the pore has an atypical shape, the diameter of a circle having the same area as the pore and the inlet may be approximated as the diameter of the pore.

The average diameter of the pores included in the activated carbon substrate may be about 4.5 nm to about 6.0 nm. The above-mentioned average diameter of pores may mean the average diameter of all pores including mesopores and micropores. As the pores have the average diameter of the size described above, it is possible to prevent coke from being generated and accumulated in the pores. In addition, the reactants, intermediate products, and final products can freely move in and out of the pores, so the catalytic activity is excellent.

The pores included in the activated carbon substrate may affect the fuel decomposition reaction and coke formation inhibition. For example, the specific surface area and volume of the mesopores may be considered important in order to increase the conversion rate and suppress the formation of coke during the process of hydrocracking fuel. Mesopores can provide adsorption sites that facilitate diffusion of free radicals of hydrocarbons and inhibit polymerization or condensation of hydrocarbon molecules. Alternatively, activated carbon-based mesopores allow micelles and aggregates to easily access the catalytically active site, thereby inhibiting coke formation.

The volume of the mesopores included in the activated carbon substrate may be from about 0.4 cm ³ g ^-1 to about 0.6 cm ³ g ^-1 . When the volume of the mesopores is ^{less than about 0.4 m 2} g ^-1 , the effect of inhibiting coke formation by the mesopores may be reduced. On the other hand, when the volume of the mesopores ^{exceeds about 0.6 m 2} g ^-1 , there is a fear that the catalytic activity is reduced.

The activated carbon substrate or catalyst compound may have a specific surface area of from about 560 m ² g ⁻¹ to about 780 m ² g ⁻¹ . As the specific surface area of the activated carbon substrate is provided in the above range, the size of the unit catalyst compound can be kept small while the catalytic reaction is performed over a sufficiently large area.

Acid sites are provided on the activated carbon substrate. The acid site may be provided in a form in which an acidic functional group is bonded to the activated carbon substrate. The acid sites include Bronsted acid sites and Lewis acid sites.

The acid sites can serve as catalytically active sites that promote fuel cracking reactions. The acid site may specifically promote a reaction for decomposing a hydrocarbon compound into a low molecular hydrocarbon compound.

For example, if the fuel is n-dodecane, the decomposition reaction of the fuel may begin with the formation of penta-coordinated carbonium ions starting from protolysis of the reactant at the Bronsted acid site. The n-dodecane carbonium ion dissociates into small molecules of paraffin or hydrogen molecules and carbenium ions. Additionally, carbenium ions are formed by the hydrate extraction reaction of n-dodecane carried out at the Lewis acid site.

The carbenium ions formed can undergo hydrate transfer reactions with intermediate products or decompose into smaller carbenium ions. Accordingly, alkane and alkene compounds can be made. The produced alkane and alkene compound can be decomposed into molecules of smaller molecular weight through the same mechanism as the reaction described above.

As described above, the Bronsted acid site and the Lewis acid site decompose the hydrocarbon compound into molecules of smaller molecular weight by different mechanisms. Accordingly, since both Bronsted acid sites and Lewis acid sites are included, hydrocarbon compounds can be decomposed by various mechanisms, thereby greatly reducing the activation energy of the fuel decomposition reaction.

The ratio of the Bronsted scattering points to the Lewis scattering points (the number of Bronsted scattering points/the number of Lewis scattering points) may be about 1.3 to about 1.6. As the Bronsted acid point and the Lewis acid point are provided in the above-described ranges, the formation of carbenium ions, formation of carbonium ions, and decomposition of hydrocarbon compounds can be efficiently performed.

Acid sites may include weak acid sites, medium acid sites, and strong acid sites. A weak acid point, a medium acid point, and a strong acid point may be divided according to the position of a peak that appears when _{ammonia elevated temperature desorption (NH 3 -TPD) is performed.} Specifically, the weak scattering point may have a peak position of about 323K to about 473K, a medium scattering point may have a peak position of about 473K to about 773K, and a strong scattering point may have a peak position of about 773K to about 923K.

The strong acid site may stabilize the above-described formed carbenium ions and the like, and thus a chain reaction for generating low molecular weight hydrocarbons from the stable carbenium ions may proceed. The density of strong acid sites may be from about 0.5 mmol-NH3/g to about 1.8 mol-NH3/g. As a strong acid site is provided in the above-described range, stabilization of carbenium ions and a chain decomposition reaction of fuel proceeding from stable carbenium ions may occur more smoothly. Accordingly, the fuel decomposition reaction efficiency by the catalyst may be improved.

The acid site may be prepared by a series of processes including a reaction of heat-treating an activated carbon substrate in an oxygen atmosphere.

The catalyst compound according to an embodiment of the present invention may be used to decompose fuel containing hydrocarbons into low molecular weight hydrocarbons. Due to the presence of the catalyst compound, the fuel decomposition reaction is promoted, and accordingly, reaction heat absorption according to the fuel decomposition reaction occurs actively. Reaction heat absorption can be used to remove the heat generated by the aircraft.

Hereinafter, a combustion device including the above-described catalyst compound will be described.

1 is a cross-sectional view showing a combustion device according to an embodiment of the present invention.

The combustion device 10 may be a device that is provided to a moving body to provide a driving force so that the moving body can be propelled. Combustion device 10 may be provided, for example, on a ship, aircraft, automobile, truck, bus, or the like.

The combustion device 10 includes a fuel pipe 100 and a combustion chamber 200 .

The fuel pipe 100 is a passage for moving the fuel stored in the moving body to the combustion chamber 200 . The fuel pipe 100 may thus further be provided with a pump for pulling up and moving the stored fuel.

The fuel pipe 100 may be provided in various forms, such as a square duct, a round pipe, and the like. The diameter and length of the fuel pipe 100 may vary depending on the type and shape of the moving body.

The fuel pipe 100 may be provided adjacent to the combustion chamber 200 . Accordingly, heat generated in the combustion chamber 200 may be diffused to the fuel pipe 100 . The heat diffused to the fuel pipe 100 heats the fuel passing through the fuel pipe 100 . As the fuel is heated and provided, the fuel may be burned faster and more efficiently in the combustion chamber 200 .

A catalyst layer 150 is provided on one surface of the fuel pipe 100 . The catalyst layer comprises a catalyst compound as described above. The catalyst compound may decompose the fuel passing through the fuel piping 100 . Specifically, the fuel containing hydrocarbon compounds is decomposed into low molecular weight hydrocarbon molecules by the catalyst compound. For example, fuels such as n-dodecane can be decomposed into molecules of alkanes, alkenes, or alkenes having 1 to 4 carbon atoms.

The above-described reaction of the catalyst layer 150 is an endothermic reaction. Accordingly, only the reaction heat required for fuel decomposition can be absorbed from the combustion chamber 200 . In particular, as the fuel pipe 100 is provided adjacent to the combustion chamber 200 , heat generated in the combustion chamber 200 may be provided to the fuel inside the fuel pipe 100 . The heat provided to the fuel can be consumed as reaction heat of the fuel decomposition reaction. Accordingly, heat generated in the combustion chamber 200 may be removed.

The catalyst layer 150 may be provided in various forms in the fuel pipe 100 . For example, the catalyst layer 150 may be provided to cover the inner surface of the fuel pipe 100 . Alternatively, the catalyst layer 150 may be positioned inside the fuel pipe 100 in a lattice form to contact the fuel over a larger area. The shape of the catalyst layer 150 may vary depending on the shape of the fuel pipe 100 and the type of moving body.

The combustion chamber 200 is a place where fuel decomposed into low molecular weight compounds through the catalyst layer 150 is burned. The fuel may be ignited and combusted at a combustion tip 210 provided in the combustion chamber 200 . By burning the fuel, the moving body can obtain propulsion.

According to an embodiment of the present invention, the catalyst compound absorbs reaction heat while decomposing the fuel, thereby providing a heat dissipation effect to the moving body.

In the above, a catalyst compound according to an embodiment of the present invention and a configuration of a combustion device including the catalyst compound have been described. Hereinafter, the advantageous effects of the above-described catalyst compounds will be looked at in more detail.

Test Example 1. Physical property test of catalyst compound

After preparing the catalyst compounds according to Examples and Comparative Examples, their physical properties were tested. The catalyst compounds according to Examples 1 and 2 were prepared by oxidizing active charcoal having a size of 30 mesh to 50 mesh at about 673 K and about 473 K, respectively, for about 2 hours in air. Catalyst compounds according to Examples 1 and 2 were prepared by heating from room temperature at a rate of about 5 K/min.

As the catalyst compound according to Comparative Example 1, untreated active charcoal was used, and as the catalyst compound according to Comparative Example 2, ZSM-5 zeolite (SiO ₂ /Al ₂ O ₃ molar ratio = 23) was used.

sample specific surface area
(m ² g ^-1 ) micropore specific surface area
(m ² g ^-1 ) mesopore specific surface area
(m ² g ^-1 ) volume
(cm ³ g ^-1 ) micropore volume
(cm ³ g ^-1 ) mesopore volume
(cm ³ g ^-1 ) average pore diameter
(nm) before use Comparative Example 2 294 248 46 0.18 0.12 0.06 2.5 Comparative Example 1 575 323 252 0.43 0.17 0.26 4.8 Example 2 563 318 245 0.42 0.17 0.25 4.8 Example 1 769 356 413 0.70 0.18 0.52 5.7 after use Comparative Example 2 8.5 - 8.5 0.025 0.0006 0.0244 226 Comparative Example 1 176 47.6 128.4 0.17 0.02 0.15 5.3 Example 2 147 26.9 120.1 0.16 0.01 0.15 5.4 Example 1 126 24.7 101.3 0.16 0.01 0.15 6.7

Referring to Table 1, it can be seen that the catalyst compound according to the example has a larger mesopore volume than the catalyst compound according to the comparative example. This means that the catalyst compound according to the example has an expanded pore structure compared to the catalyst compound according to the comparative example. In particular, the catalyst compound according to Example 1 shows that the pore structure can be expanded by high temperature. The catalyst compound according to Example 1 shows that some of the partition walls constituting the micropores are collapsed by high temperature, and thus mesopores can be generated.

Catalyst deactivation due to carbon deposition such as coke can be prevented due to an increase in the mesopore structure and an increase in specific surface area. In addition, as the reactants and intermediate products move freely through the mesopores, the catalytic activity and chain reaction rate can be improved.

Test Example 2. XPS analysis

2a and 2b show the composition of the catalyst compound according to an embodiment of the present invention and a comparative example through XPS analysis.

XPS analysis was performed to analyze the surface functional group characteristics and structural defects of the catalyst compounds of Examples and Comparative Examples. The catalyst compounds of Examples and Comparative Examples provided in this Test Example are the same as the catalyst compounds of Examples and Comparative Examples provided in Test Example 1.

FIG. 2A is a C1 peak analysis result of the catalyst compound, and FIG. 2B is an O1 peak analysis result of the catalyst compound.

Referring to FIG. 2A , both the Example and the Comparative Example showed a main peak at about 284.78 eV, which is due to the graphite structure of the activated carbon substrate. Also, the peak at about 285.59 eV is due to structural defects such as carbon with diamond structure in the activated carbon-based region. The peaks at about 286.19 eV, about 287.21 eV, and about 289.44 eV are due to carbon atoms bonded to one, two, and three oxygen atoms, respectively. This is because the electronegative oxygen atom induces a positive charge on the carbon atom. Finally, the peak at about 291.17 eV was identified as a π-π * transition loss peak.

Referring to FIG. 2B , the O1 peak at about 533.36 eV is due to a single bond between oxygen and carbon. Also, the peak at about 531.80 eV is due to the double bond between oxygen and carbon, and the peak at about 530.29 eV is due to the physically adsorbed oxygen species.

In the catalyst compound according to Example 2, the relative amount of carbon atoms bound to oxygen (CO, C = O, OC = O) was reduced from about 31.0% to about 22.4% when compared to the catalyst compound according to Comparative Example 1, The relative amount of carbon bound to carbon (CC, defect C) increased from about 63.4% to about 70%. In particular, the amount of carbon atoms single-bonded to oxygen (C-O) decreased significantly from about 16.2% to about 9.8%. This is consistent with the O1 peak analysis results showing that the amount of single bound oxygen decreased from about 78.3% to about 47.0%.

Therefore, it can be seen that the weak oxygen-bonding functional group (C-O) present on the surface of the activated carbon substrate is preferentially removed by the oxidation process for preparing the catalyst compound according to the embodiment.

Meanwhile, in the catalyst compound according to Example 1 oxidized at a higher temperature, the total amount of oxygen bound to carbon was similar to the catalyst compound according to Comparative Example. In particular, the amount of double oxygen coordinated carbon (C=O) and triple oxygen coordinated carbon (OC=O) rapidly increased from about 12.6% to about 18.1%, forming strong bonds through reoxidation of carbon atoms by molecular oxygen. can be known

Test Example 3. FT-IR analysis

3 is a graph showing the composition of a catalyst compound according to an embodiment and a comparative example of the present invention through FT-IR analysis.

In order to examine the chemical functional groups provided on the surface of the catalyst compounds of Examples and Comparative Examples, FT-IR analysis was performed in absorbance mode. The catalyst compounds of Examples and Comparative Examples provided in this Test Example are the same as the catalyst compounds of Examples and Comparative Examples provided in Test Example 1.

In both the catalyst compounds according to Examples and Comparative Examples, two bands centered ^{at about 2920 cm -1} and about 2850 cm ^-1 and a broadband band from ^{about 2985 cm -1 to about 3666 cm -1 were clearly observed.} It is confirmed that CH symmetric and asymmetric elongation bands of residual methylene functional groups ^{appear at about 2850 cm -1} and about 2920 cm ^{-1 .} These bands were found in both the spectra of the comparative example and the example, and the intensity and peak shape were also the same.

A broad band from about 2985 cm ⁻¹ to about 3666 cm ^{−1 indicates OH stretching.} This band will be caused by the hydroxyl species two types of the surface, at about 3500 cm ^-1 on the carboxylic acid and about 3605cm ^-1 and about 3393cm ^-1 due to the OH group from a phenol stretching.

Absorption bands of other oxygen-containing functional groups in the catalyst compound appeared below ^{about 2000 cm −1 .} The bands at about 1700 cm ^-1 and about 1560 cm ^-1 are due to stretching oscillations of the C=O moieties in the carboxylic acid and ketone functional groups, respectively. In addition, about 1300cm ^-1 to 1100cm ^-1 overlapping band of approximately range is due to the symmetrical stretching of the C-OH stretching vibration and the phenol functional group of ether.

Overall, the dominant functional groups on the catalyst compound surface were hydroxyl and ketone species. The type of oxygen-containing functional groups and their presence on the AC surface were sensitive to the oxidation pretreatment temperature, which was consistent with the XPS results of Test Example 2. For example, a carboxylic acid stretching band of ^{about 1700 cm -1} was remarkably observed in the spectrum of the catalyst compound according to Example 1, which was subjected to oxidation treatment at the highest temperature.

Test Example 4. Confirmation of acid properties (1)

4 is a graph analyzing the acid properties of the composition of the catalyst compound according to an embodiment and a comparative example of the present invention through ammonia elevated temperature desorption (NH _{3 -TPD).}

The desorption peak in the NH3-TPD profile of FIG. 4 was classified into a weak acid point (α: 323-473K), a medium acid point (β: 473-773K), and a strong acid point (γ: 773-923K) according to the desorption temperature. The acid density (ASD, mmol-NH ₃ /g-cat) was calculated by integrating the peak area, and the results are summarized in Table 2.

sample Weak scatter point (α)
(mmol-NH ₃ /g) middle acid (β)
(mmol-NH ₃ /g) Strong acid point (γ) (mmol-NH ₃ /g) Total acid point (mmol-NH ₃ /g) Bronsted/Lewis Sanjomby Bronsted Mountains Lewis Scattered Comparative Example 2 0.478 (30) 1.099(70) - 1.577 2.36 1.108 0.469 Comparative Example 1 0.080(8) 0.411(41) 0.521(51) 1.012 1.01 0.509 0.503 Example 2 - 0.361 (40) 0.542 (60) 0.903 1.35 0.518 0.385 Example 1 0.052(3) - 1.751 (97) 1.803 1.48 1.077 0.726

In the catalyst compound of Comparative Example 2, only weak (α) and medium (β) desorption peaks were observed. In the case of the catalyst compound including the activated carbon substrate, the acid properties showed a significant difference in Comparative Examples, Examples 1 and 2, respectively. In the case of Example 2, the total acid density was lower than that of the comparative example because the oxygen content on the surface was low as seen in the previous test example. In contrast, in the case of Example 1, not only the intensity of acid sites but also the total acid density increased due to the presence of carboxylic acid functional groups (OC=O). Specifically, the acid density of the strong acid point was about 0.521 mmol-NH ₃ /g in Comparative Example 2, but was measured as high as about 1.751 mmol-NH _{3 /g in Example 1.}

Test Example 5. Confirmation of acid properties (2)

5 is a graph showing the composition of a catalyst compound according to an embodiment and a comparative example of the present invention.

Referring to the graph of FIG. 5 , the types of acids present in the catalyst compounds of Examples and Comparative Examples can be confirmed through the FT-IR spectrum of the NH3 adsorbed catalyst compound. In the case of Comparative Example 2, it is ^{confirmed that the adsorption bands of about 1470 cm -1} and about 1637 cm ^-1 represent Bronsted (B) and Lewis (L) scattered points, respectively. In the case of Example 1, Example 2, and Comparative Example 1, it is confirmed that two bands centered at ^{about 1447 cm -1} and about 1606 cm ^{-1 represent Bronsted scattering and Lewis scattering, respectively.}

^{The amount of NH 4+} ions adsorbed to the Bronsted acid sites increased as the oxidation process temperature for preparing the catalyst compounds of Examples increased. As the oxidation process temperature increased, the activated carbon substrate was found to be richer in Bronsted acid sites than Lewis acid sites.

Test Example 6. Decomposition reaction evaluation

6 is a graph showing the activity of a catalyst compound according to an embodiment and a comparative example of the present invention through n-dodecane decomposition reaction result analysis.

The decomposition activity of n-dodecane was measured using the catalyst compounds of Examples and Comparative Examples. Catalyst compounds of Examples and Comparative Examples provided in this Test Example are the same as catalyst compounds according to Examples and Comparative Examples provided in Test Example 1, and the control indicates a case in which the catalyst is not included.

Catalytic activity for n-dodecane decomposition was measured under different temperature conditions (about 673K, about 723K, and about 773K) and a constant pressure condition of about 4 MPa. When the catalyst compound was introduced, the conversion rate and gas yield by n-dodecane decomposition were significantly improved when compared with the control. Example 1 had the highest conversion rate by decomposition of n-dodecane. Since the decomposition of n-dodecane is related to the acid sites on the catalyst surface, the conversion of n-dodecane can be determined according to the order of the total acid density in Table 2.

Conversion of long-chain hydrocarbons to gaseous products requires complete dissociation of the C-C bonds in the long-chain hydrocarbons. Such a reaction is carried out at a strong acid site, and the strong acid site performs a function of lowering the activation energy of the entire reaction. Among the tested catalyst compounds, the gas yield decreased in the order of Example 1> Example 2> Comparative Example 1> Comparative Example 2> Control, which was consistent with the order of strong acid sites in Test Example 4.

Therefore, it was confirmed that Example 1 exhibited superior activity compared to other catalysts due to high acid density and a large amount of strong acid sites.

Test Example 7. Analysis of the distribution of the decomposition reaction product

7 and 8 are graphs showing the activity of a catalyst compound according to an embodiment and a comparative example of the present invention through n-dodecane decomposition reaction product distribution analysis. Catalyst compounds of Examples and Comparative Examples provided in this Test Example are the same as catalyst compounds according to Examples and Comparative Examples provided in Test Example 1, and the control indicates a case in which the catalyst is not included.

7 shows the gas product distribution by the catalytic decomposition of n-dodecane at about 723K and about 4 MPa conditions. Ethane, propane and n-butane were the major alkane products, and ethylene and 1-butene were the major alkene products.

The gaseous product distribution varied depending on the catalyst. The distribution of gaseous product for the catalyst of Comparative Example 2 had an alkene to alkane ratio of only about 0.7. On the other hand, in the case of Example 1, Example 2, and Comparative Example 1, the alkene to alkane ratio increased and was confirmed to be about 1.3.

The overall product was classified as paraffins, C2-C4 olefins, C5-C12 olefins, aromatics, and naphthenes as shown in FIG. 8 . When the pyrolysis was carried out without a catalyst, the paraffin content exceeded about 56%. The C5-C12 olefin content was the highest when the catalyst compound of Comparative Example 2 was used, and when the activated carbon substrate was used, the C5-C12 olefin content was lower than the control test results. This is due to the influence of the different types of acid sites present on the catalyst surface. For example, in Comparative Example 2, a large number of weak acid sites were included, and thus, a large number of aromatic hydrocarbons, which were coke precursors, were formed.

Test Example 8. Heat dissipation performance test

When the n-dodecane decomposition reaction was performed using the catalyst compounds of Examples 1 and 2, and Comparative Examples 1 and 2 disclosed in Test Example 1, and the n-dodecane decomposition reaction was performed without a catalyst. The heat dissipation performance at the time (control) was tested.

The heat dissipation capacity was improved by using a catalyst. Among the tested catalysts, the catalyst of Example 1 showed the highest heat dissipation capacity of about 2,716 kJ/kg, which was about 350 kJ/kg higher than the control without catalyst. It is also higher than Comparative Examples 1 and 2 showing a heat dissipation capacity in the range of about 2,502 kJ/kg to about 2,545 kJ/kg. The catalyst of Example produced a large number of light alkenes due to the developed mesopore structure and high density of strong acid sites, and showed a high conversion of n-dodecane, and thus also showed excellent heat dissipation performance.

Although the above has been described with reference to the preferred embodiment of the present invention, those skilled in the art or those having ordinary knowledge in the technical field will not depart from the spirit and technical scope of the present invention described in the claims to be described later. It will be understood that various modifications and variations of the present invention can be made without departing from the scope of the present invention.

Accordingly, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification, but should be defined by the claims.

10: combustion device 100: fuel pipe
150: catalyst layer 200: combustion chamber
210: combustion tip

Claims (10)

activated carbon substrate;
an acid site provided on the activated carbon substrate;
The acid sites include Bronsted acid sites and Lewis acid sites,
The ratio of the Bronsted acid point to the Lewis acid point is 1.3 to 1.6,
The acid point includes at least one of a weak acid point (323-473K), a medium acid point (473-773K), and a strong acid point (773-923K), which are classified according to the desorption temperature in the NH3-TPD profile,
wherein the density of the strong acid sites on the activated carbon substrate is from 0.5 mmol-NH3/g to 1.8 mol-NH3/g. delete According to claim 1,
the catalyst compound has at least one pore,
The pores include mesopores (Mesopore) and micropores (Micropore),
wherein the micropores are pores having an average diameter of about 2 nm or less and the mesopores are pores other than micropores. 4. The method of claim 3,
The volume of the mesopores is 0.4 cm ³ g ^-1 to 0.6 cm ³ g ^-1 , the catalyst compound. 4. The method of claim 3,
The average diameter of the pores is 4.5 nm to 6.0 nm, the catalyst compound. According to claim 1,
The Bronsted acid site promotes the conversion of an aliphatic hydrocarbon compound to a carbonium ion (Carbonium Ion), a catalyst compound. According to claim 1,
The catalyst compound has a specific surface area of 560 m ² g ^-1 to 780 m ² g ^-1 , the catalyst compound. a fuel pipe through which fuel containing hydrocarbons passes; and
and a combustion chamber for burning the fuel supplied from the fuel pipe,
A catalyst layer is provided on one surface of the fuel pipe,
The catalyst layer is
activated carbon substrate;
an acid site provided on the activated carbon substrate;
The acid sites include Bronsted acid sites and Lewis acid sites,
The ratio of the Bronsted acid site to the Lewis acid site is 1.3 to 1.6, including a catalyst compound,
The acid point includes at least one of a weak acid point (323-473K), a medium acid point (473-773K), and a strong acid point (773-923K), which are classified according to the desorption temperature in the NH3-TPD profile,
wherein the density of the strong acid sites on the activated carbon substrate is from 0.5 mmol-NH3/g to 1.8 mol-NH3/g. 9. The method of claim 8,
The catalytic compound decomposes hydrocarbons contained in the fuel into hydrocarbons having a lower molecular weight. 10. The method of claim 9,
The decomposition of hydrocarbons by the catalyst compound is an endothermic reaction,
and the catalyst layer absorbs heat generated from the combustion chamber.

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