Catalyst carrier, production method therefor, and dehydrogenation catalyst comprising catalyst carrier

Abstract

The present invention relates to: a dehydrogenation catalyst carrier having an average particle diameter of 2.0-4.0 mm, a specific surface area of 50-90 ㎡ / g, and an apparent density of 0.6-1.1 g / ml; and a production method therefor. The catalyst carrier of the present invention can maintain a higher specific surface area than a catalyst having a small carrier size, thereby ensuring a higher process yield, and can increase a dehydrogenation reaction yield by reducing a pressure drop caused by a screen and reducing a reaction pressure.

Description

Catalyst carrier, method for producing the same, and dehydrogenation catalyst comprising the catalyst carrier

[0001] The present invention relates to a technology for improving catalyst performance by controlling the properties of a catalyst carrier, and more specifically, to a catalyst carrier having optimized apparent density and pore characteristics, a method for producing the same, and a dehydrogenation catalyst including such a catalyst carrier.

[0002] In general, for hydrocarbon gases, especially propane, a dehydrogenation process for producing propylene from propane using a noble metal-based dehydrogenation catalyst such as platinum has been widely practiced industrially.

[0003] Typically, the dehydrogenation process is an endothermic reaction requiring high-temperature reaction heat of 600°C or higher, and is based on a catalytic reaction. Catalysts used in dehydrogenation reactions are manufactured by supporting an active material, such as platinum, on a carrier. In dehydrogenation catalysts, the physical properties of the carrier, the active material content, and the composition and content of the cocatalyst are critical factors that determine its performance.

[0004] Conventional propane dehydrogenation processes mainly use catalysts with a specific surface area of ​​50-120 m2 / g, an apparent density of 0.5 g / cm3, and a particle size of less than 2.0 mm. Increasing the apparent density of the catalyst support can increase the amount of catalyst packed in the same reactor volume and increase the active sites. However, increasing the apparent density of a catalyst support with an average particle size of less than 2.0 mm reduces the specific surface area to less than 50 m2 / g, decreases the catalytic active sites, and degrades the catalytic performance. Therefore, there is a limit to increasing the apparent density. In addition, since an increase in the apparent density reduces the particle size of the support, the slot spacing of the screen equipment that separates the catalyst and the feed gas in the dehydrogenation device must be reduced compared to conventional methods. A decrease in the slot spacing increases the reaction pressure and reduces the process conversion rate. Therefore, in the dehydrogenation process using the existing dehydrogenation catalyst carrier, there is a limit to increasing the apparent density of the catalyst carrier, and there is a performance limit due to this limit.

[0005] [Prior Art Literature]

[0006] [Patent Document]

[0007] (Patent Document 1) KR 10-2016-0125864 A

[0008] (Patent Document 2) KR 10-2015-0137294 A

[0009] The present invention is intended to overcome the limitations of the prior art as described above, and one object of the present invention is to provide a method for manufacturing a catalyst carrier capable of achieving large-scale dehydrogenation catalyst carriers and high surface area.

[0010] Another object of the present invention is to provide a dehydrogenation catalyst carrier which is manufactured by the above manufacturing method and has a high specific surface area despite a high apparent density, thereby increasing the loading amount of the catalyst and improving the production volume and process yield when manufacturing a dehydrogenation catalyst.

[0011] Another object of the present invention is to provide a dehydrogenation catalyst comprising a catalyst carrier manufactured by the method of the present invention and a method for manufacturing the same.

[0012] Other objects, advantages and novel features of the present invention will become more apparent from the detailed description and preferred embodiments below.

[0013] One aspect of the present invention to achieve the above-described purpose is:

[0014] It relates to a dehydrogenation catalyst carrier characterized by an average particle diameter of 2.0 to 4.0 mm, a specific surface area of ​​50 to 90 m2 / g, and an apparent density of 0.6 to 1.1 g / ml.

[0015] Another aspect of the present invention relates to a method for producing a dehydrogenation catalyst carrier, characterized in that it comprises a step of heat-treating a carrier having an average particle diameter of 2.0 to 4.0 mm in a temperature range of 1000°C to 1800°C with a heat treatment amount of 50 to 2000 g to obtain a carrier having a specific surface area of ​​50 to 90 m2 / g and an apparent density of 0.6 to 1.1 g / ml.

[0016] Another aspect of the present invention relates to a dehydrogenation catalyst comprising a Group VIII noble metal component, a supporting group, and an alkali metal or alkaline earth metal supported on the catalyst support of the present invention described above. The dehydrogenation catalyst of the present invention may be, for example, a catalyst for the dehydrogenation of C2-C5 linear hydrocarbons or ethylbenzene.

[0017] Another aspect of the present invention relates to a method for producing a dehydrogenation catalyst, characterized in that, in producing a dehydrogenation catalyst having a structure in which a Group VIII noble metal component, a secondary metal, an alkali metal or an alkaline earth metal is supported on a support, the method comprises the step of heat-treating a support having an average particle diameter of 2.0 to 4.0 mm in a temperature range of 1000°C to 1800°C with a heat treatment amount of 50 to 2000 g to obtain a support having a specific surface area of ​​50 to 90 m2 / g and an apparent density of 0.6 to 1.1 g / ml.

[0018] According to the present invention, by increasing the heat supply during heat treatment in accordance with the increase in carrier size, the acid sites on the carrier surface are reduced, resulting in a decrease in the amount of coke generated on the catalyst during the dehydrogenation reaction. A decrease in coke in the dehydrogenation catalyst increases the stability of the reaction performance, which is advantageous for long-term operation and can also increase the lifespan of the catalyst.

[0019] Additionally, as the carrier size increases, the number of bonds between particles within the carrier increases, and the range over which external force is distributed expands, resulting in a relatively stronger catalyst. This increased catalyst strength increases catalyst life and reduces process operation issues caused by powder formation.

[0020] By increasing the apparent density of the catalyst manufactured using the increased size carrier of the present invention, not only can the loading amount of the catalyst be increased to increase the production of the product, but also a higher specific surface area can be maintained compared to a catalyst with a smaller carrier size, thereby achieving a higher process yield.

[0021] The present invention is described in more detail below.

[0022] The terms used in this specification should not be interpreted as limited to their usual or dictionary meanings, but should be interpreted as meanings and concepts that conform to the technical idea of ​​the present invention, based on the principle that the inventor can appropriately define the concept of the term to explain his or her own invention in the best way.

[0023] One aspect of the present invention relates to a dehydrogenation catalyst carrier characterized by having an average particle diameter of 2.0 to 4.0 mm, a specific surface area of ​​50 to 90 m2 / g, and an apparent density of 0.6 to 1.1 g / ml.

[0024] The carrier may comprise gamma, delta or theta alumina alone or as a mixture.

[0025] If the average particle size of the catalyst carrier is less than 2.0 mm, the specific surface area decreases rapidly during the carrier heat treatment, and conversely, if the average particle size of the catalyst carrier exceeds 4.0 mm, the apparent density does not increase even after the carrier heat treatment, and it is difficult to transport the catalyst to the upper part of the reactor. The average particle size of the carrier according to the present invention is derived by repeatedly measuring at least 30 times using a Vernier Caliper, and the standard deviation is made to fall within the range of 5%.

[0026] In the present invention, the alumina carrier may be gamma, delta, or theta alumina alone or as a mixture. Preferably, the alumina catalyst used has bimodal pore characteristics.

[0027] According to one embodiment of the present invention, the catalyst carrier manufactured by the above method can have a high specific surface area under the same apparent density conditions. For example, the catalyst carrier has a high specific surface area (BET) of 50 to 90 m2 / g, preferably 65 to 75 m2 / g, despite having a high apparent density in the range of 0.6 to 1.1 g / ml. Since the catalyst carrier of the present invention has a high specific surface area despite its high apparent density, the production amount of product that can be produced per unit time in a unit reactor increases, thereby ensuring high economic efficiency.

[0028] According to one embodiment of the present invention, when a catalyst carrier has the above-described specific surface area and apparent density, coke resistance and dehydrogenation performance can be further improved when used as a dehydrogenation catalyst. Accordingly, the present invention can provide a dehydrogenation catalyst comprising the above-described catalyst carrier.

[0029] Another aspect of the present invention relates to a dehydrogenation catalyst having a Group VIII noble metal component, a supporting element, and an alkali metal or alkaline earth metal supported on a porous alumina carrier. The Group VIII noble metal component is selected from the group consisting of platinum, palladium, iridium, rhodium, osmium, ruthenium, or mixtures thereof, the supporting element is one selected from the group consisting of tin, germanium, gallium, indium, zinc, and manganese, and the alkali metal or alkaline earth metal may be one selected from the group consisting of calcium, potassium, sodium, magnesium, lithium, strontium, barium, radium, and beryllium.

[0030] The dehydrogenation catalyst of the present invention may be, for example, a catalyst for dehydrogenation of C2 to C5 linear hydrocarbons or ethylbenzene, but is not necessarily limited thereto.

[0031] Another aspect of the present invention relates to a method for producing a catalyst carrier.

[0032] In the present invention, a carrier having an average particle size of 2.0 to 4.0 mm is heat-treated at a temperature range of 1000°C to 1800°C with a heat treatment amount of 50 to 2000 g to obtain a carrier having a specific surface area of ​​50 to 90 m2 / g and an apparent density of 0.6 to 1.1 g / ml.

[0033] By performing the carrier heat treatment within the heat treatment condition range set in the present invention, a carrier having a specific surface area of ​​50 to 90 m2 / g and an apparent density of 0.6 to 1.1 g / ml can be secured. Thus, according to the method for manufacturing the catalyst carrier according to one embodiment of the present invention, a high specific surface area and large size can be achieved while maintaining the surface properties of the catalyst carrier, thereby contributing to improved coking resistance of the catalyst and yield of the dehydrogenation process.

[0034] Generally, as the catalyst carrier size increases, internal thermal conductivity decreases. Therefore, even if the same amount of heat is supplied to change the carrier's properties, the rate of decrease in specific surface area is slower. Therefore, increasing the carrier size and thus enhancing heat treatment conditions allows the production of a carrier with a larger specific surface area under the same apparent density conditions.

[0035] In a method for manufacturing a catalyst carrier according to one embodiment of the present invention, the catalyst carrier is heat-treated at a temperature range of 1000°C to 1800°C with a heat treatment amount of 50 to 2000 g for 1 to 5 hours, thereby making the specific surface area of ​​the carrier 50 to 90 m2 / g. In general, a dehydrogenation catalyst carrier having a higher specific surface area may be advantageous for improving dehydrogenation performance and durability. However, a commonly used carrier, although advantageous as a catalyst carrier for dehydrogenation, has a problem of a relatively low specific surface area. Various post-treatment processes are known to increase the specific surface area, but the inherent surface properties of the carrier may be reduced after the post-treatment.

[0036] According to one embodiment of the present invention, a step of heat treatment at a specific high temperature range under a hydrogen atmosphere can be performed as a method for improving the specific surface area without changing the apparent density of the carrier. The heat treatment can preferably be performed at a temperature range of 1000°C to 1800°C, and can be performed for, for example, 1 hour to 5 hours, preferably 2 hours to 3 hours.

[0037] According to one embodiment of the present invention, the specific surface area (BET) of the carrier before heat treatment is 200 to 400 m2 / g, whereas the specific surface area (BET) of the carrier after heat treatment is 50 to 90 m2 / g, preferably 65 to 75 m2 / g. If the specific surface area (BET) of the carrier after heat treatment exceeds the above range, the physical properties of the carrier may change.

[0038] According to one embodiment of the present invention, the specific surface area of ​​the carrier can be measured by the BET (Brunauer-Emmett-Teller; BET) method. In addition, according to one embodiment of the present invention, by using a catalyst carrier, particularly a carrier having a large particle size (d=2.0 to 4.0 mm), for manufacturing the catalyst carrier, coke resistance and catalyst life can be further improved.

[0039] In the present invention, heat treatment conditions according to carrier size can be adjusted as shown in Table 1 below.

[0040] Carrier size (mm) Heat treatment temperature (℃) Heat treatment amount (g) 2.0~2.1 1000~1400 400~2000 2.2~2.3 1000~1400 400~1900 2.4~2.5 1000~1400 300~1600 2.6~2.7 1100~1500 300~1600 2.8~2.9 1100~1500 200~15 003.0~3.11100~1500200~14003.2~3.31200~1600200~13003.4~3.51200~1600100~12003.6~3.71300~1700100~11003.8~3.91300~170050~11004.01400~180050~1000

[0041] Another aspect of the present invention may include a step of heat-treating a support having an average particle diameter of 2.0 to 4.0 mm in a temperature range of 1000°C to 1800°C with a heat treatment amount of 50 to 2000 g to obtain a support having a specific surface area of ​​50 to 90 m2 / g and an apparent density of 0.6 to 1.1 g / ml in the process of manufacturing a dehydrogenation catalyst having a structure in which a Group VIII noble metal component, a secondary metal, an alkali metal or an alkaline earth metal is supported on a support.

[0042] In the present invention, platinum (Pt) is supported to act as an active site of a dehydrogenation catalyst, and tin is supported to act as a catalyst activity enhancer and a cocatalyst to prevent platinum, an active metal, from being easily deactivated at high temperatures and easily reduced in activity due to carbon deposition, thereby lowering the deactivation rate of the catalyst and increasing the stability of the catalyst, thereby suppressing hydrogenolysis, oligomerization, and coke formation on the catalyst surface, which are side reactions of dehydrogenation.

[0043] The above platinum is used as the active metal, and the auxiliary metal is selected from the group consisting of tin, germanium, gallium, indium, zinc, and manganese, with tin being particularly preferred. The alkali metal or alkaline earth metal may be selected from the group consisting of calcium, potassium, sodium, magnesium, lithium, strontium, barium, radium, and beryllium.

[0044] In the present invention, the weight ratio of the auxiliary component to the platinum component is 0.01 to 50.0 wt% / m2. If the weight ratio of the auxiliary component to the platinum component is less than 0.01 wt% / m2, the selectivity for propylene is lowered due to the cracking reaction of hydrocarbons by platinum, and if the weight ratio of the auxiliary component exceeds 50.0 wt% / m2, the dehydrogenation reaction activity is lowered.

[0045] The dehydrogenation catalyst according to the present invention preferably has a bulk density of 0.5 to 0.8 g / cc and a strength of 15 to 70 N. The strength is increased to ensure rigidity that minimizes fracture during regeneration or catalyst circulation. If the catalyst's strength is less than 15 N, it will easily fracture, making it difficult to apply to a continuous reaction system. Dehydrogenation catalysts generate coke, and after a certain reaction period, the coke is burned through an oxidation reaction to be regenerated. Thermal fracture can occur during this process. Furthermore, under conditions where the catalyst is circulated, friction or impact is applied during transport. When using a catalyst that is susceptible to impact, this can impede product flow and increase the pressure within the reactor, lowering the catalyst conversion rate. Therefore, high strength is a significant advantage in process operation. To prevent the weakening of strength due to hydrofluoric acid pretreatment, a particle crushing strength of 3.0 kgf or more can be achieved by performing plastic deformation at a high temperature of 400°C for 1 to 24 hours.

[0046] The dehydrogenation catalyst of the present invention can be prepared by various methods. Hereinafter, a platinum-tin-potassium / alumina (Pt-Sn-K / Al2O3) catalyst will be described as an example.

[0047] First, an alumina carrier having an average particle size of 2.0 to 4.0 mm is heat-treated at a temperature range of 1000°C to 1800°C with a heat treatment amount of 50 to 2000 g for 1 to 5 hours to obtain a carrier having a specific surface area of ​​50 to 90 m2 / g and an apparent density of 0.6 to 1.1 g / ml.

[0048] Next, a catalyst carrier may be sequentially impregnated with a catalyst support (e.g., potassium (K)), dried, and calcined to produce a potassium / alumina (K / Al2O3) catalyst, and then tin may be sequentially impregnated with the potassium / alumina catalyst, dried, and calcined to produce a platinum-potassium / alumina (Sn-K / Al2O3) catalyst, and then platinum may be sequentially impregnated with the tin-potassium / alumina catalyst, dried, and calcined to produce a platinum-tin-potassium / alumina (Pt-Sn-K / Al2O3) catalyst.

[0049] In the present invention, the method of impregnating the carrier with the metal active component or the auxiliary metal component may use the incipient wetness method, but other impregnation methods may also be used. The precipitation method may be the coprecipitation method, the homogeneous precipitation method, or the sequential precipitation method. When manufacturing a catalyst powder using the precipitation method, by simultaneously precipitating the active material and the carrier as components, a powdered catalyst is obtained, and the ratio of the active material can be freely controlled, and the mutual bonding force between the active material and the carrier is strengthened, so that a catalyst powder with excellent stability can be manufactured.

[0050] The introduction of a support such as potassium or tin can be carried out by, for example, impregnating the alloy carrier with KNO3 as a precursor of potassium, drying it in a dryer at 60 to 120°C for 12 to 36 hours, calcining it at 500 to 600°C in the presence of oxygen, and reducing it in the presence of hydrogen for 2 to 4 hours.

[0051] According to the present invention, when platinum and tin are introduced in optimal amounts into a potassium / alumina (K / Al2O3) catalyst based on an alumina carrier and introduced in optimal amounts as described above, coking formation can be suppressed even in a high-temperature reaction range, so that the target product can be produced in a high yield and deactivation can be suppressed for a long period of time. To this end, platinum is preferably introduced in an amount of 0.1 to 5 parts by weight relative to 100 parts by weight of alumina, more preferably in an amount of 0.1 to 2 parts by weight, and most preferably in an amount of 0.2 to 0.8 parts by weight. In addition, tin is preferably introduced in an amount of 0.1 to 10 parts by weight relative to 100 parts by weight of alumina, more preferably in an amount of 0.1 to 0.5 parts by weight, and most preferably in an amount of 0.2 to 0.4 parts by weight.

[0052] Any metal precursor used in the potassium-supporting step may be used as long as it is a commonly used precursor, but it is generally preferable to use at least one selected from metal chloride, nitrate, bromide, oxide, hydroxide or acetate precursors, and it is particularly preferable to use a metal nitrate. There is no particular limitation on the amount of the metal precursor used, but the content of potassium is preferably 0.2 to 5 wt%, and more preferably 0.5 to 1.0 wt%, based on the total weight of the final platinum-tin-potassium-alumina catalyst. However, adding more than 5 wt% of potassium is not preferable because it may block the active sites of platinum during catalyst production, and adding less than 0.2 wt% of potassium is not preferable because the amount is very small and does not have the effect of increasing the reaction activity.

[0053] Each solvent used in the above metal impregnation system may be selected from water or alcohol, with water being preferred but not limited thereto.

[0054] In addition, the heat treatment after potassium loading is performed for the purpose of forming potassium-alumina, and is preferably performed at a temperature range of 350 to 1000°C, preferably 500 to 800°C, for 1 to 12 hours, preferably 3 to 6 hours. If the heat treatment temperature is less than 350°C or the heat treatment time is less than 1 hour, the formation of potassium-alumina is not sufficient, which is not preferable, and if the heat treatment temperature exceeds 1000°C or the heat treatment time exceeds 12 hours, there is a concern that the phase of potassium-alumina may be transformed, which is not preferable.

[0055] Any commonly used tin precursor used in the tin-supporting step can be used, but generally, it is preferable to use at least one selected from chloride, nitride, bromide, oxide, or acetate precursors as the tin precursor, and tin chloride (Tin(II) Chloride) is particularly preferable. There is no particular limitation on the amount of tin precursor used, but in order to stably maintain high activity for a long time, the tin content is preferably 0.1 to 10 wt%, and more preferably 0.1 to 0.5 wt%, based on the total weight of the final platinum-tin-potassium-alumina catalyst. If tin is added in excess of 10 wt%, the amount of platinum active sites decreases during catalyst production, which is not preferable because the activity decreases. On the other hand, if tin is added in less than 0.1 wt%, tin may not be able to properly play its role of suppressing carbon deposition by preventing the sintering of platinum particles and maintaining a small platinum particle size, thereby improving dispersion.

[0056] When preparing a tin precursor solution, an acid is used. The usable acid solution is an acid that exists in a liquid (solution) state at room temperature, and may be selected from the group consisting of hydrochloric acid, nitric acid, sulfuric acid, hydrofluoric acid, and phosphoric acid, but is not limited thereto.

[0057] After impregnating the tin, heat drying is performed to remove the remaining moisture. The drying temperature and drying time can be limited according to general moisture drying conditions. For example, the drying temperature can be set to 50 to 200°C, preferably 70 to 120°C, and the drying time can be set to 3 to 24 hours, preferably 6 to 12 hours. In addition, the heat treatment is performed for the purpose of forming tin-potassium-alumina, and is preferably performed at a temperature range of 350 to 1000°C, preferably 500 to 800°C, for 1 to 12 hours, preferably 3 to 6 hours. This is not preferable when the heat treatment temperature is less than 350°C or the heat treatment time is less than 1 hour because the formation of tin-potassium-alumina is not sufficient, and when the heat treatment temperature exceeds 1000°C or the heat treatment time exceeds 12 hours, there is a concern that the tin-potassium-alumina phase may be transformed.

[0058] The introduction of platinum is for example H2PtCl as a precursor of platinum. 6· A platinum-potassium / alumina (Pt-K / Al2O3) catalyst can be prepared by impregnating 6H2O (chloroplatinic acid hexahydrate) into the potassium / alumina catalyst, drying in a dryer at 60 to 120°C for 12 to 36 hours, calcining in the presence of oxygen at 500 to 600°C, and reducing in the presence of hydrogen for 2 to 4 hours. The introduction of tin can be prepared by impregnating, for example, tin-acetylacetonate as a tin precursor into the platinum-potassium / alumina catalyst, drying in a dryer at 60 to 120°C for 12 to 36 hours, calcining in the presence of oxygen at 500 to 600°C, and reducing in the presence of hydrogen for 2 to 4 hours.

[0059] Any commonly used precursor may be used as the platinum precursor used in the platinum-supporting step. Generally, it is preferable to use at least one selected from chloroplatinic acid, platinum oxide, platinum chloride, and platinum bromide precursors as the platinum precursor, and it is particularly preferable to use chloroplatinic acid. There is no particular limitation on the amount of platinum precursor used, but it is preferable that the platinum content be 0.1 to 5 wt% based on the total weight of the final platinum-tin-potassium-alumina catalyst. If more than 5 wt% of platinum is added, it is difficult to obtain a high degree of platinum dispersion during catalyst production, and a lot of expensive platinum is used, which is not preferable. On the other hand, if less than 0.1 wt% is added, the active sites of platinum, which is the active metal of the dehydrogenation reaction, are not sufficiently formed, which is not preferable because it is difficult to produce a product with high selectivity and yield.

[0060] Additionally, the dehydrogenation catalyst of the present invention may also contain a halogen component. The halogen component may be fluorine, chlorine, bromine, or iodine, or a mixture thereof. Chlorine is a preferred halogen compound. The halogen component is typically present in combination with the porous carrier material and the alkaline component. The halogen component is preferably uniformly dispersed throughout the dehydrogenation catalyst. The halogen component may comprise 0.01 to 15 wt% of the final dehydrogenation catalyst, calculated on an elemental basis. The halogen component may be incorporated into the dehydrogenation catalyst in any suitable manner before, during, or after the incorporation of other catalyst components, or during the preparation of the carrier material.

[0061] The catalyst manufactured by the present invention provides improved performance that is differentiated from that of catalysts manufactured by conventional methods, namely, high hydrocarbon conversion and selectivity, performance stability, improved resistance to coking, and ease of coke removal.

[0062] The dehydrogenation catalyst produced by the method of the present invention can have a wide range of applications. Therefore, it can be used in particular for the dehydrogenation of hydrocarbons or other organic compounds, particularly C2 to C5 linear hydrocarbons. In the present invention, saturated hydrocarbons, such as ethane, propane, butane, isobutane, and pentane, are the main target reactants, and are converted into olefins having a carbon skeleton corresponding to the saturated hydrocarbon used as the reactant through the dehydrogenation reaction, i.e., ethylene, propylene, 1- or 2-butylene, isobutylene, and pentene.

[0063] In addition, the catalyst of the present invention can be used as a catalyst for various reactions such as hydrosulfuration, hydrodenitrification, desulfurization, hydrodesulfurization, dehydrohalogenation, reforming, steam reforming, cracking, hydrocracking, hydrogenation, dehydrogenation, isomerization, dismutation, oxychlorination and dehydrocyclization, oxidation and / or reduction reactions, and Claus reactions.

[0064] Another aspect of the present invention relates to an improved dehydrogenation method using the dehydrogenation catalyst of the present invention.

[0065] For example, according to the present invention, a method for manufacturing the dehydrogenation catalyst is used to produce a mixed gas containing propane, hydrogen, and oxygen at a reaction temperature of 600 to 1000°C, preferably 550 to 800°C, a high pressure of 0.1 to 5.0 kgf / ㎠, a H2 / C3 ratio of 0 to 1.0, and a liquid space velocity of the mixed gas and the catalyst of 0.1 to 30 hr. -1 , preferably 2~20 hr -1Propylene can be produced from propane by an oxidative dehydrogenation reaction under gas phase conditions.

[0066] The method for producing propylene from propane according to the present invention is a method for producing propylene effectively even under harsh high-temperature conditions, and when the dehydrogenation catalyst according to the present invention is applied, propylene production increases and the decrease in catalyst activity is low. That is, the method for producing propylene according to the present invention can utilize the reaction heat generated by the oxidation reaction of oxygen, and exhibits a high propane conversion rate by overcoming the reaction equilibrium. In addition, even when the reaction conditions are harsh, the decrease in catalyst performance is small, and even when deactivation is severe, it shows an improved effect in terms of long-term use stability. In addition, as a secondary effect of the present invention, there is a function to remove coke on the catalyst during the reaction, thereby improving the catalytic activity.

[0067] The present invention will be described in more detail below with reference to examples. However, these examples are provided for the purpose of illustrating the present invention and should not be construed as limiting the scope of protection of the present invention.

[0068] Example

[0069] Example 1: Preparation of dehydrogenation catalyst

[0070] <Manufacture of catalyst carrier>

[0071] Alumina having a spherical gamma crystallinity and an average particle size of 2 mm was purchased from Sasol, Germany, and used as a carrier for catalyst synthesis by thermal deformation at a temperature of 1000°C for 2 hours in an air flow of 300 ml / min using a tubular electric furnace (Korea Electric Furnace). At this time, the specific surface area (BET) of the carrier after heat treatment in the steam atmosphere was 70 m2 / g.

[0072] <Catalyst Manufacturing>

[0073] Tin, platinum, and potassium were sequentially loaded onto the above heat-treated alumina carrier. Tin chloride (SnCl2, >99%, Sigma) in an amount of 0.3% based on the weight of the carrier, hydrochloric acid (HCl, >35%, JUNSEI) in an amount of 0.5%, and nitric acid (HNO3, 70%, Yakuri) in an amount of 0.1% were dissolved in distilled water twice the weight of the carrier, and then 15 g of heat-treated alumina carrier was added to support it. The support solution was dried using a rotary evaporator, stirred at 25 rpm for 3 hours at 80°C, and then dried by rotating at 25 rpm for 1.5 hours at 80°C under reduced pressure. Afterwards, it was calcined in a furnace at 600°C for 2 hours and dried at 230°C for 24 hours. Afterwards, 15 g of tin-supported alumina was dissolved in chloroplatinic acid (H2PtCl6·6H2O, 99.95%, Aldrich) in an amount of 0.5% based on the weight of the carrier. 0.5% hydrochloric acid, 0.5% nitric acid, and 0.3% nitric acid were added to distilled water twice the amount of the carrier and loaded. The loaded solution was dried using a rotary evaporator, stirred at 25 rpm for 3 hours at 80°C, and then dried by rotating at 25 rpm for 1.5 hours at 80°C under reduced pressure. After that, it was calcined in a furnace at 550°C for 2 hours and dried at 230°C for 24 hours.

[0074] Afterwards, the alumina support loaded with tin and platinum was loaded with 1% potassium nitrate (KNO3, >99%, Sigma-Aldrich) and 0.5% hydrochloric acid in distilled water twice the amount of the support. The support solution was dried using a rotary evaporator, stirred at 25 rpm for 3 hours at 80°C, then dried by rotating at 25 rpm for 1.5 hours at 80°C under reduced pressure, and heat-treated in a 600°C furnace for 2 hours to produce a dehydrogenation catalyst.

[0075]

[0076] Examples 2-11

[0077] A platinum-tin-potassium / alumina (Pt-Sn-K / Al2O3) catalyst was manufactured in the same manner as in Example 1, except that the heat treatment conditions were changed according to the carrier size as described in Table 2 below.

[0078]

[0079] Comparative Examples 1-5

[0080] A platinum-tin-potassium / alumina (Pt-Sn-K / Al2O3) catalyst was manufactured in the same manner as in Example 1, except that the heat treatment conditions were changed according to the carrier size as described in Table 2 below.

[0081]

[0082] Test Example 1: Measurement of physical properties of dehydrogenation catalysts

[0083] The physical properties of the catalysts manufactured in Examples 1 to 11 and Comparative Examples 1 to 5, such as specific surface area and apparent density, were measured using the following methods, and the results are shown in Table 2 below.

[0084] To measure the specific surface area, the surface area and porosity of the catalyst were observed using a BET (Brunauer-Emmett-Teller Surface Analyzer, BELSORP). N2 gas was used as the adsorption gas, and adsorption was performed at 77 K. At this time, since the sample needed to be pretreated before adsorbing the N2 gas, the pretreatment was performed in a vacuum at 230°C for more than 3 hours before analysis. The apparent density (BD; Bulk Density) (g / cc) was measured according to ASTM D1895.

[0085]

[0086] Test Example 2: Performance Test of Dehydrogenation Catalyst

[0087] In order to confirm the performance of the dehydrogenation catalyst according to the present invention, the dehydrogenation performance was compared using a laboratory reactor. 1.5 g of the catalysts manufactured in Examples 1 to 11 and Comparative Examples 1 to 5 were each filled in a quartz reactor with a volume of 7 ml, and then a mixture of propane, hydrogen, and oxygen gas was supplied to perform the dehydrogenation reaction. At this time, the reaction temperature was 650°C, the pressure was 2.0 kgf / cm2, the H2 / C3 ratio was 0.5, and the liquid space velocity was 15 hr. -1 The dehydrogenation reaction was performed while maintaining the reaction temperature. The gas composition after the reaction was analyzed using a gas chromatograph connected to the reaction apparatus, and the yield of propylene in the product after the reaction was obtained. The results are shown in Table 2 below.

[0088] The coke content was determined by exhausting the reaction gas with nitrogen after 100 hours of reaction time, lowering the temperature to room temperature, burning the catalyst with carbon deposits at 550°C for 12 hours, and calculating the total accumulated amount of coke generated on the catalyst during the reaction by measuring the loss in combustion.

[0089] Carrier size (mm)Apparent density (g / ml)Specific surface area (㎡ / g)Temperature (℃)Heat treatment amount (g)Time (h)Yield (%)Coke (%)Screen gap (mm)Comparative example 11.90.55988002200234.59.01.58Example 12.00.69010002000235.08.01.62Example 22.00.78012001600335.57.01.61Example 32.40.757511001300236.56.51.94Example 42.40.807214001100337.06.01.93Example 53.00.807312001100237.35.62.43Example 63.00.85711500900237.65.22.41Example 73.40.85721300900238.04.72.75Example 83.40.90701600700338.24.32.73Example 93.80.95691400700237.93.53.08Example 103.81.0671700400338.02.93.06Example 114.01.1501800400337.53.03.22Comparative Example 24.10.959517001100237.32.93.30Comparative Example 33.00.55869001100235.16.52.61Comparative Example 43.00.97251900400331.93.91.93Comparative Example 53.80.93291400700637.63.23.08

[0090] As confirmed by the results in Table 2 above, it can be seen that the catalyst of the present invention exhibits very stable and excellent performance in terms of yield in the dehydrogenation process. In addition, since the catalyst of the present invention can maintain a higher specific surface area, a higher process yield can be secured. Accordingly, according to the present invention, the pressure drop problem due to the screen can be reduced and the reaction pressure can be reduced, thereby increasing the reaction yield. Since a productivity increase of approximately 3% is possible when the apparent density increases by 0.01 g / ml, a polypropylene polymer with high commercial productivity can be produced in high yield by using the carrier and catalyst of the present invention.

[0091] Although the present invention has been described in detail above with reference to preferred embodiments thereof, it will be apparent that the present invention is not limited to the above-described embodiments, and that many modifications may be made by those skilled in the art within the scope of the technical idea of ​​the present invention.

Claims

1. A dehydrogenation catalyst carrier characterized by an average particle diameter of 2.0 to 4.0 mm, a specific surface area of ​​50 to 90 m2 / g, and an apparent density of 0.6 to 1.1 g / ml.

2. A dehydrogenation catalyst carrier according to claim 1, characterized in that the carrier comprises gamma, delta or theta alumina alone or as a mixture.

3. A dehydrogenation catalyst in which a Group VIII noble metal component, a support compound, and an alkali metal or alkaline earth metal are supported on the catalyst support of paragraph 1.

4. A dehydrogenation catalyst according to claim 3, characterized in that the Group VIII noble metal component is one selected from the group consisting of platinum, palladium, iridium, rhodium, osmium, ruthenium, or mixtures thereof, the auxiliary metal is one selected from the group consisting of tin, germanium, gallium, indium, zinc, and manganese, and the alkali metal or alkaline earth metal is one selected from the group consisting of calcium, potassium, sodium, magnesium, lithium, strontium, barium, radium, and beryllium.

5. A dehydrogenation catalyst according to claim 3, characterized in that the dehydrogenation catalyst is a catalyst for dehydrogenation of a C2 to C5 linear hydrocarbon or ethylbenzene.

6. A method for producing a dehydrogenation catalyst carrier, characterized by comprising the step of heat-treating a carrier having an average particle size of 2.0 to 4.0 mm in a temperature range of 1000°C to 1800°C with a heat treatment amount of 50 to 2000 g to obtain a carrier having a specific surface area of ​​50 to 90 m2 / g and an apparent density of 0.6 to 1.1 g / ml.

7. A method for producing a dehydrogenation catalyst carrier, characterized in that the heat treatment in paragraph 6 is performed for 1 to 5 hours.

8. A method for producing a dehydrogenation catalyst carrier, characterized in that, in paragraph 6, gamma, delta or theta alumina is used alone or as a mixture as the carrier.

9. A method for manufacturing a dehydrogenation catalyst carrier, characterized in that in paragraph 6, the method further includes a step of adjusting heat treatment conditions according to carrier size as shown in the table below: A method for producing a dehydrogenation catalyst having a structure in which a Group 10.VIII noble metal component, a secondary metal, an alkali metal or an alkaline earth metal is supported on a support, characterized in that it comprises a step of heat-treating a support having an average particle diameter of 2.0 to 4.0 mm in a temperature range of 1000°C to 1800°C with a heat treatment amount of 50 to 2000 g to obtain a support having a specific surface area of ​​50 to 90 m2 / g and an apparent density of 0.6 to 1.1 g / ml.

Images