KR102046771B1 - Dehydrogenation catalyst - Google Patents

Abstract

The present invention is a dehydrogenation catalyst in which a platinum group metal, an auxiliary metal, and a sodium component are supported on an alumina support, wherein the molar ratio of auxiliary metal to platinum is 0.3-1.6, the molar ratio of sodium to platinum is 6.8-15.3, and the catalyst is KOH. The dehydrogenation catalyst according to the present invention is characterized in that the dehydrogenation catalyst according to the present invention has a high hydrocarbon conversion, selectivity and performance stability, and improved coking resistance. Coke removal ease can be provided.

Description

Dehydrogenation catalyst {DEHYDROGENATION CATALYST}

The present invention relates to a catalyst used in a hydrocarbon dehydrogenation reaction, and more particularly, to improve the long-term operation performance of the catalyst, and to operate the dehydrogenation process under a hydrogen ratio downward condition, thereby improving the process yield. It relates to a digestive catalyst.

Catalytic dehydrogenation of alkanes to produce alkenes (olefin hydrocarbons) is an important and well known hydrocarbon conversion process in the petroleum refining industry. This is because alkenes are generally useful as intermediate products in the production of other more expensive hydrocarbon conversion products. For example, propylene can be used for the production of polymers and propylene glycol, butylene can be used for high octane number motor fuels, and isobutylene can be used for preparing methyl-t-butyl ether, gasoline additives.

Dehydrogenation of hydrocarbon gases, such as catalytic dehydrogenation of alkanes, proceeds at high temperatures of at least 550 ° C. As the catalytic reaction proceeds at high temperatures, side reactions to it entail pyrolysis and coke formation reactions, and the extent of these side reactions is a key factor in determining the selectivity and activity of the catalyst. The coke formation reaction, one of the side reactions, lowers the overall reaction conversion rate by blocking the contact with the reactants by covering the active material on the catalyst with coke. In addition, as the formation of coke proceeds, the inlet of the pores present in the catalyst is blocked, thereby promoting inactivation of the active substance present in the pores.

US Patent Publication 2015/0202601 A1 discloses a Group IIIA metal selected from gallium, indium, thallium and combinations thereof; Group VIII precious metals selected from platinum, palladium, rhodium, iridium, ruthenium, osmium and combinations thereof; At least one dopant selected from iron, chromium, vanadium and combinations thereof; And selective promoter metals selected from sodium, potassium, rubidium, cesium, magnesium, calcium, strontium, barium and combinations thereof; Disclosed are alkane dehydrogenation catalyst compositions comprising a catalyst support selected from silica, alumina, silica alumina composites, rare earth controlled alumina, and combinations thereof.

Korean Patent Publication No. 2014-0123929 discloses a dehydrogenation catalyst composition for hydrocarbons, comprising: nano-sized composites containing group VIII components; Protective film forming agents containing Group IVA components and sulfur; Alkaline component; Halogen component; And a support having an inner core consisting of alpha alumina and an outer layer comprising a mixture of gamma alumina and delta alumina.

In the conventionally known patents related to dehydrogenation catalysts, the content of the active ingredient of the catalyst and the type of the support is the mainstream, and the content of acid spots, which is one of the physical characteristics of the catalyst, is still absent. Therefore, there is an urgent need to develop a dehydrogenation catalyst having an acid point amount within an appropriate range and excellent catalyst activity, selectivity and coke stability.

Applicants have found that by adjusting the acid point of the catalyst to a predetermined range, the dehydrogenation process can be performed under the hydrogen / hydrocarbon ratio lowering conditions, thereby greatly improving the process yield. In particular, Applicants have found that catalysts having an acid content within the scope of the present invention provide lower coke-generation, better long term stability or greater activity.

One object of the present invention is to provide a catalyst suitable for the dehydrogenation reaction which allows for increased catalyst long term operating performance, low coke generation and good process yield.

It is another object of the present invention to provide a dehydrogenation process that achieves increased catalyst long term operating performance, low coke generation and good process yield.

One aspect of the present invention for achieving the above object,

Dehydrogenation catalyst with platinum group metal, auxiliary metal, and sodium component on the support, the molar ratio of sodium to platinum is 6.8-15.3, the molar ratio of auxiliary metal to platinum is 0.3-1.6, and 20 ~ when titrating the catalyst with KOH A dehydrogenation catalyst characterized by having an acid point amount of 150 μmol KOH / g catalyst.

The catalyst is supported by 0.3 to 0.8 wt% platinum and 0.4 to 0.9 wt% sodium based on the total weight of the catalyst.

The catalyst has a volume density of 0.55 to 0.9 g / cc.

The support of the catalyst has mesopores having an average pore size of 5 to 100 nm, total pore volume of 0.1 to 2.1 cm 3 / g, and an average pore size of 0.1 to 20 μm, and a total pore volume of 0.1 to 21 cm 3 / g. It has a double pore size distribution that includes all of the macro pores.

Another aspect of the invention,

In the method for producing a catalyst for hydrocarbon dehydrogenation reaction,

Providing a support having binary pore properties;

Dispersing a sodium precursor on the support to support sodium in the support;

Sequentially impregnating, drying, and calcining the sodium / support catalyst with tin and platinum to prepare a platinum-tin-sodium / alumina support catalyst,

The molar ratio of sodium to platinum is 6.5-15.3, the molar ratio of auxiliary metal to platinum is 0.3-1.6, and when the catalyst is titrated with KOH, the dehydrogenation catalyst is characterized in that it has an acid point of 20 to 150 ml KOH / g catalyst. It relates to a manufacturing method.

Another aspect of the invention relates to a hydrocarbon dehydrogenation process comprising contacting with a dehydrogenation catalyst of the invention.

The dehydrogenation catalyst according to the present invention can improve the catalyst long-term operation performance by increasing the propylene yield and reducing the coke by optimizing the promotion effect of the auxiliary metal and platinum by increasing the molar ratio of the auxiliary metal to platinum.

The dehydrogenation catalyst of the present invention can provide high hydrocarbon conversion and selectivity and performance stability, improved coking resistance and easy coke removal.

In addition, the catalyst of the present invention prevents a phenomenon in which coke increases rapidly when the hydrogen / hydrocarbon ratio is lowered in the hydrocarbon dehydrogenation reaction by adjusting the acid point of the catalyst to a predetermined range, so that the operation of the catalyst in the hydrogen / hydrocarbon ratio downward condition is improved. It is possible to improve the process economics.

The catalyst of the present invention can increase the catalyst volume density to increase the catalyst input mass within the same reactor volume, thereby improving reactor performance and improving process yield.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail.

As used herein, it should be noted that the term 'comprising' or 'comprising' does not exclude the presence of other elements. Likewise, it should also be understood that a description of a method that includes certain steps does not exclude the inclusion of other steps when it is stated that a particular step is included.

The dehydrogenation catalyst of an embodiment of the present invention is a dehydrogenation catalyst having a platinum group metal, an auxiliary metal, and a sodium component supported on a support, wherein the molar ratio of sodium to platinum is 6.8-15.3, and the molar ratio of auxiliary metal to platinum is 0.3-1.6. When the catalyst is titrated with KOH, it has an acid point amount of 20-150 μmol KOH / g catalyst.

The main metal of the catalyst of the present invention is a platinum group metal. The platinum group component may include precious metal components such as platinum, palladium, ruthenium, rhodium, iridium, osmium or mixtures thereof. Platinum group metals may be present in the dehydrogenation catalyst as chemical elements or as metal elements with one or more of the other components of the complex as compounds such as oxides, sulfides, halides, acid halides and the like. The platinum component comprises 0.3 to 0.8 wt% of the dehydrogenation catalyst, calculated on the basis of the element.

The catalyst of the present invention comprises 0.3 to 0.8 wt% platinum, 0.4 to 0.9 wt% sodium and 0.1 to 0.5 wt% tin, based on the total weight. When the content of the platinum component is less than 0.3% by weight, the reaction activity of the dehydrogenation reaction may be lowered, and when it exceeds 0.8% by weight, the selectivity of propylene may be lowered by the cracking reaction of the hydrocarbon by platinum.

As auxiliary metals, those selected from the group consisting of tin, germanium, gallium, indium, copper, zinc, antimony, bismuth and manganese can be used, and tin is particularly preferable.

The dehydrogenation catalyst according to the present invention is a catalyst having a high molar ratio of secondary metal to platinum, and the molar ratio of secondary metal to platinum is preferably 0.3 to 1.6. If the molar ratio of auxiliary metal to platinum is less than 0.3, tin is not desirable because it prevents the sintering of platinum particles and keeps the particle size of platinum small and improves dispersion so that it does not play a role in suppressing carbon deposition. If the molar ratio of the secondary metal to the iron exceeds 1.6, the excess of the secondary metal may reduce the promoting effect on the reaction activity of the catalyst.

Sodium in the catalyst of the invention blocks the acid point on the support to reduce or substantially block unwanted side reactions, while at the same time enhancing the catalytic activity of active metals such as platinum.

The molar ratio of sodium to platinum in the dehydrogenation catalyst according to the invention is preferably 6.8 to 15.3. If the molar ratio of sodium to platinum is less than 6.8, the acid point of the support may not be properly controlled, and the amount of side reactions and coke production may increase, and if it exceeds 15.3, sodium may be excessively supported to block the active point of platinum, thereby lowering the activity of the catalyst. have.

In addition to further reducing the overall acidity of the catalyst, the presence of sodium can block sites on the metal surface that are active for undesirable side reactions. If the content of sodium is less than 0.4% by weight, the acidity of the support is increased to increase the cracking reaction and coke production, so that the selectivity of the dehydrogenation reaction is reduced, and when the content of sodium is more than 0.9% by weight, the catalyst The activity may be reduced to reduce the conversion of the dehydrogenation reaction.

The catalyst of the present invention may optionally further comprise an alkali or alkaline earth metal selected from the group consisting of calcium, potassium, magnesium, lithium, strontium, barium, radium and beryllium.

In the present invention, the acidity amount is a measure of the free acid component on the catalyst support, and is expressed as a value (μmol) of potassium hydroxide (KOH) neutralized by an acid point present in 1 g of the catalyst support.

In the present invention, if the acid point of the catalyst is less than 20 μmol KOH / g, if the acid point of the support is too small, the interaction is weak to cause a lot of metal movement and sintering may occur. Can be thermally decomposed to produce unwanted methane and to cause rapid catalyst deactivation by forming carbon deposits on the catalyst.

In the hydrocarbon dehydrogenation reaction, coke increases rapidly when the hydrogen / hydrocarbon ratio (H ₂ / HC) is lowered. When the acid concentration of the catalyst is adjusted within the above range, the coke increases rapidly even when the hydrogen / hydrocarbon ratio is lowered. It can prevent. Therefore, when the catalyst of the present invention is used, the dehydrogenation process can be operated under the hydrogen / hydrocarbon ratio lowering condition in which the yield of the dehydrogenation process is improved, thereby greatly increasing the process yield.

It is preferable to have a volume density of 0.55 to 0.9 g / cc of dehydrogenation of the present invention, and the volume density of the catalyst determines the amount of the catalyst charged into the process, which is a factor that determines the total active density of the catalyst introduced into the process. If the volume density of the catalyst is less than 0.55 g / cc, the catalytic active metal per unit volume decreases the catalyst performance, while if the catalyst density exceeds 0.9 g / cc, the specific surface area is reduced due to the phase change of the support to reduce the dispersion of the metal Catalyst performance may be reduced.

Preferred shapes of the catalyst in the present invention are spherical particles having a pellet size of 1.2 to 2.0 mm. Spherical support particles can be produced continuously by well-known oil-dropping methods, which methods can be prepared by any technique known in the art. For example, the spherical alumina catalyst support forms an alumina slurry with Ziegler alumina or alumina hydrosol by reacting hydrochloric acid with aluminum metal, and combines the obtained hydrosol or slurry with a suitable gelling agent to maintain the resulting mixture at a high temperature. It can manufacture by the method of dripping into an oil bath. When the droplets of the mixture form gelled spheres, they are recovered and subjected to aging and drying to further improve the physical properties of the support. Aged and gelled particles can then be washed and calcined to obtain spherical crystalline alumina support.

The catalyst according to the invention may further comprise 0.1 to 3.0% by weight of the halogen component relative to the total weight of the catalyst. As the halogen component, one selected from the group consisting of chlorine, phosphorus and fluorine is used, and chlorine is particularly preferable. If the halogen content is less than 0.1% by weight, the formation of coke on the catalyst is rapidly increased, the coke regeneration of the catalyst is low, platinum dispersibility is reduced during catalyst regeneration, and when the halogen content is more than 3.0% by weight, precious metals by halogen The poisoning of the catalyst lowers the activity of the catalyst. That is, the halogen component, in particular chlorine, is combined with the aluminum element of the alumina support to attenuate the characteristics of the Lewis acid possessed by the alumina itself, thereby facilitating the desorption of the product, thereby suppressing the formation of coke. The formation of coke is adsorbed on the support itself and the reaction is completed, or the main product / by-product produced at the active site is spill-over, accumulated in the support and finally produced through an additional coke formation reaction. Degradation of the product to facilitate the desorption of the product can reduce the amount deposited on the support to reduce coke production. In addition, the halogen component controls the sintering of platinum during the catalyst regeneration process.

In the catalyst according to the invention, the support is TiO ₂ , SiO ₂ , Al ₂ O ₃ , ZrO ₂ , Cr ₂ O ₃ , Nb ₂ O ₅ And those selected from the group consisting of mixed components thereof, and alumina is preferable. The θ-crystallinity of alumina is a factor that determines the degree of coke formation, and the alumina (Al ₂ O ₃ ) support preferably has a θ-crystal phase of 90% or more. The use of γ-alumina results in high structural reactivity due to the acid point of the alumina itself, changes in alumina crystallinity and reduced specific surface area during the reaction, and α-alumina is characterized by low specific surface area of the platinum group active metals. It is preferable that the alumina support has a θ-crystalline phase of 90% or more because the degree of dispersion decreases and the overall active area of platinum is reduced to show low catalytic activity.

In the present invention, the support has an average pore size of 5 to 100 nm, a meso pore having a total pore volume of 0.1 to 2.1 cm 3 / g, and an average pore size of 0.1 to 20 μm, and a total pore volume of 0.1 to 21 cm 3 / g. It has a double pore size distribution that includes all of the macro pores. Due to this dual pore size distribution characteristic, the catalyst of the present invention shows improved activity and ease of regeneration in the dehydrogenation reaction during the reaction.

If the pores of the support are less than 5 nm, the material transfer rate is lowered. If the pores of the support are more than 20 μm, the strength of the support is lowered. In other words, when the pore size is 10 nm or less, it is loose diffusion and transition diffusion is performed at 10-1000 nm. In the dehydrogenation reaction, 10-100 nm pores are preferable.

The support has a specific surface area of 75 to 140 m 2 / g. If the specific surface area of the support is less than 75 m 2 / g, the dispersibility of the metal active component is lowered. If the specific surface area is more than 140 m 2 / g, the gamma crystallinity of the alumina is maintained high, thereby increasing the side reaction.

The catalyst according to the present invention preferably has a strength of 16 to 75 N, and increases the strength so that the catalyst has less rigidity in regeneration or circulation of the catalyst. If the strength of the catalyst is less than 16N, it is easily broken and difficult to apply to the continuous reaction system. The dehydrogenation catalyst is accompanied with the formation of coke, and after a certain reaction, the coke is burned and regenerated through an oxidation reaction, and thermal cracking occurs during the process. In addition, friction and impact are applied during transfer under conditions in which the catalyst is circulated and operated. In the case of using a catalyst that is weak in impact, having a high strength has a great advantage in process operation because it lowers the conversion rate of the catalyst by disturbing the flow of the product and raising the pressure in the reactor.

The dehydrogenation catalyst according to the present invention increases the molar ratio of the secondary metal to platinum to 0.3-1.6, thereby optimizing the promotion effect of the secondary metal and platinum to improve the catalyst long-term operation performance by increasing the propylene yield and reducing the coke, and By adjusting the acid point to a predetermined range, it is possible to operate at the hydrogen / hydrocarbon consumption down condition where the process yield is improved by preventing the coke increase rapidly when the hydrogen / hydrocarbon ratio is lowered in the hydrocarbon dehydrogenation reaction, thereby improving the process economy. In addition, by increasing the catalyst volume density and increasing the catalyst input mass in the same reactor volume, the reactor performance can be improved to improve the process yield.

Another aspect of the invention relates to a process for the preparation of a catalyst for the dehydrogenation of hydrocarbons. When the dehydrogenation catalyst is prepared by the method of the present invention, a support having dual pore characteristics is provided.

Various supports may be used as the support in the present invention. Preferably, the support may be alumina (Al ₂ O ₃ ), which is 90% or more of theta-crystalline phase. The support having the dual pore characteristics has mesopores having an average pore size of 5 to 100 nm, a total pore volume of 0.1 to 2.1 cm 3 / g, an average pore size of 0.1 to 20 μm, and a total pore volume of 0.1 to 21 cm 3. It may be a support including all macro pores of / g.

Sodium precursor is dispersed in the support to support sodium in the support. Specifically, after the sodium metal precursor is dissolved in a solvent to prepare a sodium precursor solution, the precursor solution is impregnated into the alumina carrier.

Subsequently, the sodium / support catalyst is sequentially impregnated with tin and platinum, dried and calcined to prepare a platinum-tin-sodium / alumina catalyst. First, the tin precursor is dissolved in a solvent to prepare a tin precursor solution, and the tin precursor solution is impregnated with sodium-alumina to obtain tin-sodium / alumina. The platinum precursor is then dissolved in a solvent to prepare a platinum precursor solution, and the platinum precursor solution is impregnated in tin-sodium-alumina to obtain a platinum-tin-natalium-alumina catalyst. In the method of the present invention during the manufacturing process

In the present invention, by adjusting the molar ratio of the auxiliary metal to platinum and the molar ratio of sodium to platinum, and by adjusting the sintering temperature can be prepared to have an acid point of 20 ~ 150 mlKOH / g catalyst when titrating the catalyst with KOH.

The solvent may be selected from water or alcohol, respectively, and water is preferred, but is not limited thereto.

The precursor of the metal used in each step may be any of the precursors commonly used. Metal chloride, nitrate, bromide, oxide, and hydroxide are generally used. ) And one or more kinds selected from acetate precursors can be used.

In the present invention, the method may further include firing at 1000 ° C. to 1400 ° C. for 1 hour to 2 hours before supporting the active metal or auxiliary metal. In the case where the firing temperature is less than 1000 ° C. or the heat treatment time is less than 1 hour, the formation of metal-alumina is not sufficient, and if the heat treatment temperature is more than 1400 ° C. or the heat treatment time is more than 2 hours, It is not preferable because the phase may be denatured.

Another aspect of the present invention is a dehydrogenation catalyst having a platinum group metal, auxiliary metal, alkali metal or alkaline earth metal component supported on a support, wherein the molar ratio of auxiliary metal to platinum is 0.3-1.6, and the molar ratio of sodium component to platinum is 6.8. It is -15.3, and relates to a hydrocarbon dehydrogenation method comprising the step of contacting the catalyst with a dehydrogenation catalyst characterized in that it has an acid content of 20 ~ 150 μmol KOH / g catalyst when titrated with KOH. The process of the present invention can be applied to the dehydrogenation of linear hydrocarbons such as ethane, propane, normal butane, pentane, hexane, heptane or octane. For example, the method of the present invention can be used as a process for producing propylene through the dehydrogenation process of propane, but is not necessarily limited to this process.

Dehydrogenation can be carried out at atmospheric or elevated pressure. The hydrocarbon / hydrogen volume ratio is preferably in the range of 0.1 to 1.5 to optimize the rate of dehydrogenation. In proportion to the deactivation rate, other volume ratios may be used.

The hydrocarbon dehydrogenation method according to the present invention has a small reduction in the performance of the catalyst even when the reaction conditions are severe, and an improved effect in terms of long-term stability even when the deactivation is severe. Dehydrogenation of propane at high temperatures using the dehydrogenation catalyst of the present invention can improve propane conversion, propylene selectivity in the product, and propylene yield.

The catalyst of the present invention is suitable for the hydrogenation and dehydrogenation of any hydrocarbon species. Some non-limiting examples include hydrogenation reactions such as for converting unsaturated hydrocarbons to less saturated or fully saturated hydrocarbons; And dehydrogenation reactions such as conversion of ethane to ethylene, conversion of propane to propylene, conversion of isobutane to isobutylene or conversion of ethylbenzene to styrene. The reactant hydrocarbons may be provided in pure form, treated with a diluent such as nitrogen or hydrogen, combined with air or oxygen, or by any method known in the art.

An Example is given to the following and this invention is demonstrated in detail. However, the following examples are only for illustrating specific embodiments of the present invention, and the contents of the present invention are not limited by the examples.

Example

Preparation Example of Dehydrogenation Assay Catalyst

Alumina having spherical gamma crystallinity prepared according to US Pat. No. 4,542,113 was purchased from Sasol, Germany, and 1050 on a flow of air 300 ml / min using a tubular electric furnace (Korea Electric Furnace). Heat for 2 hours at a temperature of ℃

It was modified and used as a support for catalytic synthesis. The crystallinity of alumina was measured by X-ray analysis, and theta crystallinity was over 90%.

Using the heat-modified alumina support, a catalyst was prepared by a room temperature / temperature adsorption support method. 0.0489 g of tin chloride (SnCl ₂ ,> 99%, Sigma), 0.6429 g of hydrochloric acid (HCl,> 35%, JUNSEI), and 0.0804 g of nitric acid (HNO ₃ , 70%, Yakuri) were dissolved in 30 g of distilled water, followed by thermal deformation. 20 g of alumina was added and supported. The supporting solution was dried using a rotary evaporator (HAHNSHIN Scientific Co.), stirred at 25 rpm for 1.5 hours at room temperature, and then dried by rotating at 25 rpm for 1.5 hours at 80 ° C under reduced pressure. For complete drying it was dried for 15 hours in a 105 ℃ oven, heat-treated for 3 hours in a 700 ℃ heating furnace. Thereafter, 20 g of tin-supported alumina was added to 31.494 g of distilled water in which 0.1991 g of chloroplatinic acid (H ₂ PtCl ₆ 6H ₂ O, 99.95%, Aldrich), 0.2143 g of hydrochloric acid, and 0.0536 g of nitric acid were dissolved. The supporting solution was dried using a rotary evaporator, stirred at 25 rpm for 1.5 hours at room temperature, and then dried at 25 rpm for 1.5 hours at 80 ° C under reduced pressure, dried for 15 hours in an oven at 105 ° C, 600 Heat treatment was performed for 3 hours in a heating furnace. Thereafter, 20 g of alumina loaded with tin and platinum was added to 42.0584 g of distilled water in which 0.5228 g of sodium nitrate (NaNO ₃ ,> 99%, Sigma-Aldrich) and 0.2682 g of hydrochloric acid were dissolved. The supporting solution was dried using a rotary evaporator, and stirred at 25 rpm for 1.5 hours at room temperature, and then dried at 25 rpm for 1.5 hours at 80 ° C. under reduced pressure, and dried for 15 hours in an oven at 105 ° C., 600 The dehydrogenation catalyst was prepared by heat treatment for 3 hours in a heating furnace.

The catalyst was prepared by the above preparation method using alumina having different physical properties (molar ratio of auxiliary metal to platinum, acid content) in Table 1 below.

Examples 1-4

As shown in Table 1 below, various dehydrogenation catalysts were prepared to include the density or acidity of platinum for the auxiliary metals within the scope of the present invention.

Comparative Examples 1 to 3

As shown in Table 1, the dehydrogenation catalyst was prepared in the same manner as in Example 1 except for changing the density of platinum to sodium or the acid point amount of the catalyst. In Comparative Example 3, when the sodium was supported, it was prepared using the supporting liquid only with distilled water.

Experimental Example 1 Performance Test of Dehydrogenation Catalyst

Dehydrogenation was carried out according to the procedure described in the above catalyst performance evaluation method while varying the molar ratio of platinum to the auxiliary metal (tin) or the acid point amount of the catalyst, and the selectivity, conversion and yield were measured. The measurement results are shown in Table 1 below.

[Catalyst Performance Evaluation Method]

The performance of the dehydrogenation catalyst according to the present invention was evaluated by the following method,

3.2 ml of the catalysts prepared in Examples 1 to 4 and Comparative Examples 1 to 3 were respectively filled in a quartz reactor having a volume of 7 ml, and then a mixed gas of propane and hydrogen was supplied to dehydrogenation, respectively. At this time, the ratio of hydrogen and propane was fixed at 0.2: 1, and under adiabatic conditions, the reaction temperature was 620 ° C, the absolute pressure was 0.5 atm, and the liquid space velocity was maintained at 15hr ^-1 to perform dehydrogenation. The gas composition after the reaction was analyzed by gas chromatography connected with the reaction apparatus to measure propane conversion, propylene selectivity and yield in the product.

Example Comparative example unit One 2 3 4 One 2 3 Pt wt% 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Sn wt% 0.2 0.2 0.3 0.3 0.2 0.2 0.2 Na wt% 0.7 0.8 0.7 0.8 0.4 0.9 0.7 H ₂ / HC 0.2 0.2 0.2 0.2 0.2 0.2 0.2 Reaction pressure kgf / ㎠ 0.5 0.5 0.5 0.5 0.5 0.5 0.5 LHSV h ^-1 15 15 15 15 15 15 15 Reaction temperature ℃ 620 620 620 620 620 620 620 Scatter  μmolKOH / g 115 75 59 36 160 65 110 Specific surface area ㎥ / g 84.5 86.6 83.9 83.3 83.9 87.0 83.7 Conversion rate  % 26.9 25.7 29.6 28.8 23.9 24.8 20.8 Selectivity  % 94.7 94.5 94.8 95.0 94.5 94.5 94.5 yield  % 25.5 24.3 28.0 27.4 22.6 23.5 19.7 Coke Content  wt% 4.8 3.5 1.5 0.4 5.9 3.6 3.4

As confirmed through the results in Table 1, the catalyst of Comparative Example 1 having a sodium content of 0.4 has a small amount of sodium in the support as compared to the catalysts of the present invention (Examples 1 to 4), and thus the deactivation rate is fast and coke. Also was deposited a lot. On the other hand, the catalyst of Comparative Example 2 having a sodium content of 0.9 was loaded with excess sodium as compared to the catalysts of the present invention (Examples 1 to 4), thereby degrading the activity of the catalyst. In addition, it can be seen that the catalyst of Comparative Example 3 using only the supporting solution of sodium as water has low catalytic activity because sodium is not dispersed properly on the support. In addition, since the content of tin increases, the catalyst activity increases by increasing the desorption rate by increasing the electron density of platinum as well as the neutralizing effect of the support. Thus, even when the molar ratio of tin to platinum in the catalyst of the present invention is increased, You can see the performance increase.

In addition, when the amount of acid in the range is within the scope of the present invention, it can be confirmed that the dehydrogenation process can be performed even under the hydrogen / hydrocarbon ratio lowering conditions, thereby improving the process yield. In addition, oxidative dehydrogenation reaction was carried out using the catalyst of the present invention in which the acid point was adjusted, resulting in high propane conversion, propylene selectivity in the product, and propylene yield, indicating very good catalytic activity. Therefore, it can be seen that the oxidative dehydrogenation catalyst of the present invention exhibits very high catalytic activity due to high propane conversion, propylene selectivity, and propylene yield in the propane oxidative dehydrogenation reaction.

While the above has been described in detail with respect to preferred embodiments of the present invention, this description is for illustrative purposes only, those skilled in the art to which the present invention pertains various modifications, changes within the spirit and scope of the present invention It will be understood that additions, additions, and the like, and such modifications and changes should be understood as belonging to the protection scope of the present invention as defined by the following claims.

Claims (16)

Dehydrogenation catalyst supporting platinum group metal, auxiliary metal, and sodium component on the support, the molar ratio of sodium to platinum group metal is 6.8 to 15.3, the molar ratio of auxiliary metal to platinum group metal is 0.3 to 1.6, and when titrating the catalyst with KOH Dehydrogenation catalyst, characterized in that it has an acid point amount of 20 ~ 150 μmol KOH / g catalyst. The dehydrogenation catalyst according to claim 1, wherein the catalyst comprises 0.3-0.8 wt% of platinum group metal, 0.1-0.5 wt% of tin component and 0.4-0.9 wt% of sodium component, based on the total weight of the catalyst. . The dehydrogenation catalyst of claim 1, wherein the catalyst has a volume density of 0.55 to 0.9 g / cc. The dehydrogenation catalyst of claim 1, wherein the support is selected from the group consisting of TiO ₂ , SiO ₂ , Al ₂ O ₃ , ZrO ₂ , Cr ₂ O _3, and Nb ₂ O ₅ and mixed components thereof. . 5. The dehydrogenation catalyst of claim 4, wherein the support is alumina having at least 90% of θ-crystalline phase. According to claim 1, wherein the support has an average pore size of 5 to 100 nm, a meso pore having a total pore volume of 0.1 to 2.1 cm 3 / g and an average pore size of 0.1 to 20 ㎛, a total pore volume of 0.1 to 21 Dehydrogenation catalyst, characterized in that the support including all of the macropores of cm 3 / g. The dehydrogenation catalyst of claim 1, wherein the platinum group metal is at least one selected from the group consisting of platinum, palladium, rhodium, ruthenium, iridium, and osmium. The dehydrogenation catalyst of claim 1, wherein the auxiliary metal is at least one selected from the group consisting of tin, germanium, gallium, indium, zinc, and manganese. The dehydrogenation catalyst of claim 1, wherein the auxiliary metal is tin. The dehydrogenation catalyst of claim 1, wherein the support has a specific surface area of 75 to 140 m 2 / g. In the method for producing a catalyst for the dehydrogenation reaction of a hydrocarbon,
Providing a support having binary pore properties;
Dispersing a sodium precursor on the support to support sodium in the support;
Sequentially impregnating, drying, and calcining the sodium / support catalyst with tin and platinum to prepare a platinum-tin-sodium / alumina support catalyst,
The molar ratio of sodium to platinum is 6.8 to 15.3, the molar ratio of auxiliary metals to platinum is 0.3 to 1.6, and when the catalyst is titrated with KOH, the dehydrogenation catalyst is characterized in that it has an acid point of 20 to 150 μmol KOH / g catalyst. Manufacturing method. The mesopore according to claim 11, wherein the support having dual pore characteristics has an average pore size of 5 to 100 nm, a total pore volume of 0.1 to 2.1 cm 3 / g, and an average pore size of 0.1 to 20 μm, and total pore size. A method for producing a dehydrogenation catalyst, characterized in that the support comprises all of the macropores having a volume of 0.1 to 21 cm 3 / g. The method of claim 11, wherein the support is alumina (Al ₂ O ₃ ) having at least 90% of theta-crystalline phase, and the auxiliary metal is tin. The method of claim 11, wherein the method further comprises calcining at 1000 ° C. to 1400 ° C. for 1 hour to 2 hours before supporting the active metal or auxiliary metal. A method of hydrocarbon dehydrogenation comprising contacting a hydrocarbon with the dehydrogenation catalyst of any one of claims 1 to 10. The method of claim 15, wherein the hydrocarbon comprises one of ethane, propane, propane, normal butane, pentane, hexane, heptane or octane.