Preparation method of ruthenium oxide supported catalyst for chlorine production and catalyst prepared therefrom

Abstract

The present invention relates to a method for preparing a ruthenium oxide supported catalyst for chlorine production, and specifically to a catalyst in which the degree of ruthenium component supported on the outer surface of a carrier is significantly improved, and a method for preparing a catalyst that provides a high chlorine conversion rate even at a relatively low reaction temperature when using the catalyst to prepare chlorine, and a catalyst prepared by the catalyst. According to an embodiment of the present invention, a method for preparing a ruthenium oxide supported catalyst is provided, and the ruthenium oxide supported catalyst is a ruthenium oxide catalyst for chlorine production, comprising: step (a), dissolving a ruthenium compound in an organic solvent to prepare a solution, and loading it on one or more carriers selected from titanium dioxide and aluminum oxide; step (b), drying; step (c), calcining. According to an embodiment of the present invention, in particular, a simplified process can be provided for preparing a catalyst containing ruthenium oxide only in the outer surface shell of a titanium dioxide carrier without alkali pretreatment, thereby facilitating scale expansion.

Description

Technical Field

[0001] The present invention relates to a method for preparing a ruthenium oxide supported catalyst for chlorine production, and in particular to a catalyst in which the degree to which the ruthenium component is supported on the outer surface of a titanium dioxide carrier is significantly improved, and a method for preparing a catalyst that provides a high chlorine conversion rate even at a relatively low reaction temperature when using the catalyst to prepare chlorine, and a catalyst prepared by the catalyst. Background Art

[0002] The method of producing chlorine by catalytic oxidation of hydrogen chloride is derived from the Deacon Process, and representative catalysts include ruthenium-based catalysts, copper-based catalysts, and cerium-based catalysts. In particular, compared with copper-based catalysts and cerium-based catalysts, ruthenium-based catalysts have high activity at a small amount of catalyst and a lower reaction temperature.

[0003] The ruthenium oxide supported catalyst among the above ruthenium-based catalysts is useful as a catalyst for oxidizing hydrogen chloride to produce chlorine using oxygen. It is known that the currently commercialized Sumitomo Corporation's Korean authorized patent No. 10-1561812 proposes a method for producing chlorine, which is a method for oxidizing hydrogen chloride to produce chlorine using a catalyst in which a ruthenium compound is loaded on a carrier, a ruthenium oxide supported catalyst obtained by oxidizing the loaded catalyst, a ruthenium oxide supported catalyst obtained by reducing the loaded catalyst and then oxidizing the loaded catalyst, or a catalyst containing ruthenium oxide only in the outer surface shell of the carrier so that the activity per unit weight of ruthenium contained in the catalyst is improved.

[0004] However, the above-disclosed method requires an alkali preloading treatment and the like in order to contain ruthenium oxide only in the outer surface shell layer of the carrier, and thus has a disadvantage that the preparation method of the catalyst is complicated.

[0005] The reaction of producing chlorine by oxidation of hydrogen chloride is a balanced reaction. The higher the reaction temperature, the less favorable the balance is, which will reduce the equilibrium conversion rate. Therefore, the lower the reaction temperature of the catalyst, the more favorable the reaction balance is, and the higher the conversion rate of hydrogen chloride can be.

[0006] However, most of the catalysts mentioned in the prior art show high activity mainly at high temperatures, and there is a phenomenon that the performance of the catalyst will decrease in a short period of several months when operating at high temperatures. That is, the current situation is that it is difficult for supported ruthenium oxide to simultaneously meet the two conditions of thermal stability and catalyst life.

[0007] Japanese Patent Publication No. 2014-105128 discloses a method for preparing a ruthenium oxide catalyst used in a method for producing chlorine by oxidizing hydrogen chloride with oxygen. Although alcohol is disclosed as a solvent for supporting the catalyst, there is no record of the composition or effect of being able to load the ruthenium component only on the outer surface of a titanium dioxide carrier, and therefore there are limitations.

[0008] Japanese Patent Publication No. 2013-169516 also discloses a method for preparing a ruthenium oxide catalyst used in a hydrogen chloride oxidation method, and discloses the use of alcohol as a solvent for a supported catalyst, but does not record specific details about exhibiting a high chlorine conversion rate at low temperatures of 200 to 300°C, and therefore has limitations.

[0009] Korean Patent Publication No. 2014-0102205 relates to a method for preparing ruthenium oxide in which ruthenium oxide and silicon dioxide are supported on a titanium dioxide carrier. However, at this time, there is no specific mention of the composition or effect of being able to support the ruthenium component only on the outer surface of the titanium dioxide carrier, so there is a limitation.

[0010] Therefore, there is an urgent need to develop a highly active catalyst that can overcome the above-mentioned problems and simply use alcohol as a solvent, thereby simplifying the reaction process and only loading the ruthenium component on the outer surface of the carrier, thereby having a higher yield even at a lower reaction temperature.

[0011] (Patent Document 1) Japanese Patent Publication No. 2014-105128 (June 9, 2014)

[0012] (Patent Document 2) Japanese Patent Publication No. 2013-169516 (November 6, 2015)

[0013] (Patent Document 3) Korean Patent Publication No. 2014-0102205 (August 21, 2014) Summary of the invention

[0014] Technical issues

[0015] The purpose of the present invention is to solve all the above problems.

[0016] Another object of the present invention is to provide a method for preparing a ruthenium oxide supported catalyst used in a process for oxidizing hydrogen chloride to produce chlorine.

[0017] In particular, the object is to provide a simplified process for preparing a catalyst which contains ruthenium oxide only on the outer surface of the support without alkaline pretreatment.

[0018] Therefore, an object of the present invention is to provide a catalyst whose S / R, a VMS measurement value indicating the degree to which a ruthenium component is supported on the outer surface of a carrier, is close to zero.

[0019] In addition, the object of the present invention is to provide a method for preparing a highly dispersed ruthenium oxide supported catalyst and a ruthenium oxide supported catalyst prepared thereby, wherein the highly dispersed ruthenium oxide supported catalyst has a high hydrogen chloride conversion rate and high activity in the chlorine production process even at a relatively low reaction temperature, preferably around 250°C.

[0020] Technical Solution

[0021] The characteristic configuration of the present invention for achieving the above-mentioned object of the present invention and realizing the characteristic effects of the present invention described below is as follows.

[0022] According to an embodiment of the present invention, there is provided a method for preparing a ruthenium oxide supported catalyst for supporting ruthenium oxide for chlorine production, comprising the following steps: step (a), dissolving a ruthenium compound in an organic solvent to prepare a solution, and loading the solution onto one or more supports selected from titanium dioxide and aluminum oxide; step (b), drying; and step (c), calcining.

[0023] According to an embodiment of the present invention, relative to 100 parts by weight of the dry pre-catalyst, the ruthenium oxide supported catalyst may include 70 to 80 parts by weight of the carrier, less than 5 parts by weight of the ruthenium compound, and 15 to 25 parts by weight of the organic solvent.

[0024] The organic solvent in step (a) is a monohydric alcohol, preferably a primary alcohol with a carbon number of C3 or above, and may be 1-propanol, but is not limited thereto.

[0025] According to an embodiment of the present invention, the specific surface area of ​​the titanium dioxide carrier in step (a) is 5 to 300 m 2 / g. Preferably 5 to 100 m 2 / g, but is not limited to this.

[0026] In addition, in the step (b), drying is carried out for 3 to 5 hours under air conditions of 80 to 120°C. After the drying step, the content of ruthenium oxide can be less than 5 parts by weight, preferably 2 parts by weight, relative to 100 parts by weight of the total weight of the dried catalyst.

[0027] In the step (c), sintering is performed at 300 to 400° C. for 2 to 4 hours.

[0028] According to an embodiment of the present invention, a method for preparing a ruthenium oxide supported catalyst is provided, wherein the carrier is manufactured by the following steps: mixing a powder carrier mixture containing one or more selected from titanium dioxide and aluminum oxide, titanium dioxide sol or aluminum oxide sol, an organic binder and distilled water to prepare a mixture; extruding the mixture; drying and cutting into a molded body; and firing. In addition, at this time, the carrier contains 30 to 50 parts by weight of the powder carrier mixture, 1 to 9 parts by weight of titanium dioxide sol or aluminum oxide sol, 0.5 to 1.5 parts of organic binder and 20 to 40 parts by weight of distilled water relative to 100 parts by weight of the total weight before drying.

[0029] According to an embodiment of the present invention, a ruthenium oxide supported catalyst prepared by the above preparation method is provided. The prepared catalyst can be used to oxidize hydrogen chloride to produce chlorine.

[0030] The ruthenium oxide supported catalyst may be in the form of one or more selected from the group consisting of powder, particles and granules, preferably in the form of granules. In addition, the VMS measurement value of the ruthenium oxide supported catalyst, ie, S / R, is less than 0.5.

[0031] According to an embodiment of the present invention, a method for producing chlorine based on oxidation of hydrogen chloride is provided, which is carried out in the presence of the catalyst. In this case, the reaction temperature for producing chlorine can be 200-300°C, preferably 250°C.

[0032] Beneficial Effects

[0033] The catalyst of the present invention can be provided for chlorine production based on oxidation of hydrogen chloride.

[0034] According to the embodiments of the present invention, in particular, a simplified process for preparing a catalyst containing ruthenium oxide only in the outer surface shell layer of a titanium dioxide carrier without alkali pretreatment can be provided, thus facilitating scale-up.

[0035] In particular, a catalyst is provided whose S / R value measured by VMS showing the degree to which a ruthenium component is supported on the outer surface of a carrier is close to 0.

[0036] According to an embodiment of the present invention, a method for preparing a highly dispersed ruthenium oxide supported catalyst is provided, which has a high hydrogen chloride conversion rate and high activity in a chlorine production process even at a relatively low reaction temperature, preferably around 250°C. DETAILED DESCRIPTION

[0037] The detailed description of the present invention described below will refer to specific embodiments that can implement the present invention as examples. These embodiments are described in detail so that those skilled in the art can implement the present invention. It should be understood that the multiple embodiments of the present invention are different from each other but not necessarily mutually exclusive. For example, the specific shapes, structures and characteristics recorded herein are associated with an embodiment and can be implemented in other embodiments without departing from the spirit and scope of the present invention. In addition, it should be understood that the position or configuration of individual constituent elements within each disclosed embodiment can be changed without departing from the spirit and scope of the present invention. Therefore, the detailed description described below is not restrictive, and as long as it is properly explained, the scope of the present invention is limited only by the attached claims and the scope equivalent to the claims.

[0038] Hereinafter, several preferred embodiments of the present invention are described in detail so that those skilled in the art can easily implement the present invention.

[0039] According to an embodiment of the present invention, a method for preparing a ruthenium oxide supported catalyst is provided, wherein the ruthenium oxide supported catalyst is a ruthenium oxide catalyst for producing chlorine, comprising the following steps: step (a), dissolving a ruthenium compound in an organic solvent to prepare a solution, and loading the solution onto one or more carriers selected from titanium dioxide and aluminum oxide; step (b), drying; and step (c), calcining.

[0040] Unlike the known art, the catalyst of the present invention does not need to be pretreated with alkali in order to contain only the ruthenium oxide component on the outer surface shell of the titanium dioxide carrier. Therefore, it can be simply prepared in three steps of loading, drying and firing. Therefore, it is possible to simplify the preparation method while maintaining the catalytic activity, which is conducive to future scale expansion. This can provide a favorable effect on the time and economy of the preparation process.

[0041] According to an embodiment of the present invention, relative to 100 parts by weight of the dry pre-catalyst, the ruthenium oxide supported catalyst may include 70 to 80 parts by weight of the carrier, less than 5 parts by weight of the ruthenium compound, and 15 to 25 parts by weight of the organic solvent.

[0042] In particular, the content of ruthenium oxide in the catalyst finally produced after the drying step and the firing step is 5 parts by weight or less, preferably 2 to 4 parts by weight, and most preferably 2 parts by weight.

[0043] As the support, the titanium dioxide support may use anatase titanium dioxide, rutile titanium dioxide, amorphous titanium dioxide or a mixture thereof.

[0044] In addition, the titanium dioxide support may include oxides such as aluminum oxide, zirconium oxide or niobium oxide. According to an embodiment of the present invention, rutile titanium dioxide is preferably provided.

[0045] The specific surface area of ​​the titanium dioxide carrier can be measured by the commonly used BET method, and the specific surface area is 5 to 300 m 2 / g, preferably 5 to 100 m 2 When the specific surface area is larger than the above range, it is difficult to ensure the thermal stability of ruthenium oxide, and when it is smaller than the above range, it is difficult to achieve high dispersion, so there is a problem of reduced catalyst activity.

[0046] The alumina support is preferably α-alumina, which has high thermal conductivity, which helps to ensure thermal stability during the reaction, and also has a low BET specific surface area, so it is not easy to absorb other impurities, and is therefore preferred.

[0047] According to an embodiment of the present invention, the ruthenium compound may exist in the form of a complex salt, and may include metal salts such as halides, halides, oxyacid salts, oxyhalides, chlorides, etc. For example, it may include RuCl3 and RuBr3, K3RuCl6, K2RuCl6, K2RuO4, Na2RuO4, Ru2OCl4, Ru2OCl5, Ru2OCl6, etc., but is not limited thereto.

[0048] According to an embodiment of the present invention, the ruthenium compound is preferably a halide, and most preferably ruthenium chloride containing chloride. Depending on the situation, the ruthenium compound can provide a hydrate of the ruthenium compound, and can provide two or more selected from the ruthenium compounds.

[0049] Ruthenium chloride can be mixed in a solvent in powder form, and a solid support is suspended in the solvent to form a precipitate, thereby being deposited on the solid support. The above-mentioned load includes impregnation or dipping, at which time, the temperature is 0 to 100°C for conventional applications, preferably 0 to 50°C, and the pressure is 0.1 to 1 MPa for conventional applications, preferably atmospheric pressure. The load can be carried out in an air atmosphere or an inert gas atmosphere such as nitrogen, helium, argon, carbon dioxide, etc., and water vapor may be included in this case. It is preferably carried out in the inert gas atmosphere, but is not limited thereto.

[0050] The organic solvent in step (a) can be a monohydric alcohol, providing a primary alcohol of C3 or above. Preferably, 1-propanol. According to the present invention, compared with the known technology, an alcohol solvent is used as a solvent to replace high-purity water such as distilled water, ion-exchanged water or ultrapure water.

[0051] According to an embodiment of the present invention, a C3 alcohol organic solvent is preferably provided, preferably 1-propanol, which can utilize the high wettability and hydrophobicity of the solution to load the ruthenium component only on the outer surface of the titanium oxide molded support having a hydroxyl group, and provide an effect of improving the dispersibility of ruthenium loaded on the surface of the titanium oxide molded support or the powder support.

[0052] That is, the hydrophobicity and wettability of the C3 alcohol group can be used to provide a highly active catalyst. In particular, compared with the external surface loading degree and catalyst performance of the catalyst supported by ultrapure water or ethanol, the external surface loading degree of the catalyst supported by propanol as an alcohol solvent is more excellent and provides a higher initial activity.

[0053] In order to provide these effects, the following VMS results of the present invention were derived.

[0054] The degree of ruthenium component loading on the outer surface of the carrier is expressed by the following mathematical formula. The degree of ruthenium component loading on the outer surface was measured by VMS (visual measurement system). The closer the number in the following mathematical formula is to 0, the higher the degree of loading on the outer surface.

[0055] Mathematical formula 1

[0056]

[0057] R: The distance from any point (A) on the outermost edge of a horizontal cross section (circle) of a cylindrical catalyst to the center of the same horizontal cross section.

[0058] S: The distance from point (A) to point (B) where the ruthenium oxide component disappears, measured on a straight line from the point (A) to the center of the same horizontal cross section.

[0059] According to the embodiment of the present invention, based on the external surface loading degree (S / R) result value in Table 3, it can be known that according to the catalyst preparation method of the present invention and the catalyst prepared therefrom, when 1-propanol is used, the external surface loading degree is close to 0 compared with using ultrapure water as a solvent. Therefore, the catalyst of the present invention can load the ruthenium component only on the external surface of the titanium oxide carrier having a hydroxyl group.

[0060] Furthermore, a simple preparation method is provided which can be prepared in three steps of loading, drying and firing, and can further provide the effect of scale-up.

[0061] In the step (b), drying can be carried out under air conditions of 80 to 120° C. for 3 to 5 hours. Drying can be carried out in a rotating and stirring manner. The drying container can be vibrated or a stirrer located in the container can be used, but is not limited thereto. The drying temperature can be conventional room temperature to about 100° C., and the pressure can be conventional 0.1 to 1 MPa, preferably atmospheric pressure.

[0062] After the drying step, the content of ruthenium oxide may be 5 parts by weight or less, preferably 2 parts by weight, relative to 100 parts by weight of the dried catalyst.

[0063] In the step (c), the calcination can be carried out at 300-400°C for 2-4 hours. Thereafter, it is cooled to room temperature. The calcination temperature is a conventional temperature, preferably 250-450°C. As an oxidizing gas, for example, a gas containing oxygen can be used. Its oxygen concentration is conventionally about 1-30% by volume. The oxygen source can usually be air or pure oxygen, and can contain an inert gas or water vapor when necessary. The oxidizing gas can preferably be air, and the calcination is carried out at about 350°C in an electric furnace with air flow for about 3 hours, and then cooled to room temperature, thereby finally preparing a ruthenium oxide catalyst.

[0064] As described above, according to an embodiment of the present invention, it is possible to prepare a supported ruthenium oxide in which ruthenium oxide is supported on one or more supports selected from titanium dioxide and aluminum oxide. At this time, usually, the oxidation number of ruthenium is 4, providing ruthenium dioxide (RuO2). However, the oxidation number and morphology are not limited thereto.

[0065] According to an embodiment of the present invention, the carrier is prepared by the following method.

[0066] The carrier is prepared by the following steps: mixing a powder carrier mixture of one or more selected from titanium dioxide and aluminum oxide, titanium dioxide sol or aluminum oxide sol, an organic binder and distilled water to prepare a mixture; extruding the mixture; drying and cutting into a molded body; and firing.

[0067] At this time, relative to 100 parts by weight of the pre-dried carrier, 30 to 50 parts by weight of the powder carrier mixture, 1 to 9 parts by weight of titanium dioxide sol or aluminum oxide sol, 0.5 to 1.5 parts of an organic binder and 20 to 40 parts by weight of distilled water may be included.

[0068] The mixture is mixed and extruded into noodle-shaped strands with a diameter of 2 to 3 mmφ, and then dried to form a mold. At this time, the mixture is dried at 50 to 70°C for 1 to 3 hours. Thereafter, the mixture is cut into a molded body with a length of 2 to 4 mm. At this time, the mixture is fired at 400 to 800°C in air for 2 to 4 hours. The detailed conditions for drying and firing can generally be applied to the conditions for drying and firing of the above-mentioned catalyst, so the description thereof is omitted.

[0069] According to an embodiment of the present invention, in order to prepare the final ruthenium oxide supported catalyst, a carrier prepared by the above-mentioned carrier preparation method that satisfies the particle size, size distribution, surface area, pore structure, etc. suitable for the ruthenium catalyst composition is used, which can ultimately provide the optimal ruthenium oxide supported catalyst.

[0070] According to an embodiment of the present invention, the chlorine production process can be carried out by oxidizing hydrogen chloride to produce chlorine gas. In this case, the ruthenium oxide supported catalyst prepared by the above preparation method can be used.

[0071] The above-mentioned ruthenium oxide supported catalyst can be selected from one or more of powder, particle and granule form, preferably in the form of granule or powder, most preferably in the form of granule. The diameter is preferably below 5mm. When the diameter of the molded body is too large, it is unfavorable for the activity of the catalyst.

[0072] According to an embodiment of the present invention, the S / R of the ruthenium oxide supported catalyst as a VMS measurement value is 0.5 or less. Therefore, it is possible to provide high activity under the temperature conditions in the chlorine production reaction described later.

[0073] According to an embodiment of the present invention, there is provided a method for producing chlorine based on the oxidation of hydrogen chloride, which is carried out in the presence of a catalyst prepared by any of the above-mentioned preparation methods. The reaction methods include fixed bed method or fluidized bed method, gas phase reaction, etc., preferably gas phase reaction. The oxidation reaction is an equilibrium reaction. When carried out at too high a temperature, the equilibrium conversion rate will decrease. Therefore, it is preferably carried out at a relatively low temperature. The reaction temperature is usually 100 to 500°C, preferably 200 to 450°C, and most preferably 250°C. In addition, the reaction pressure is usually 0.1 to 5MPa. Air or pure oxygen can be used as the oxygen source. The theoretical molar amount of oxygen relative to hydrogen chloride is 1 / 4 mole, but usually 0.1 to 10 times the oxygen is provided. In addition, the supply rate of hydrogen chloride is expressed by the gas supply rate for each 1L of catalyst (L / h; 0°C, 1 atmospheric pressure conversion), that is, GHSV, which is usually 10 to 20000h -1 However, the amount of the catalyst added at this time may be changed mainly according to the temperature, the amount of the catalyst and the amount of the chlorine product to be prepared.

[0074] The following describes the configuration and function of the present invention in more detail through the preferred embodiments of the present invention, but they are only preferred examples of the present invention, and the present invention is not limited thereto no matter how they are interpreted.

[0075] The contents not described here are contents that can be fully deduced by those skilled in the art, and thus the description thereof is omitted.

[0076] Example 1

[0077] <Preparation of carrier>

[0078] 40.0 g of titanium dioxide powder, 0.8 g of an organic binder, 29.0 g of ultrapure water heated to 60°C, and 5.0 g of titanium dioxide sol were mixed. The obtained mixture was extruded into noodle-shaped strands with a diameter of 2.0 mmφ, dried in air at 60°C for 2 hours, and then cut into molded bodies with a length of 2 to 4 mm. The obtained molded body was fired in air at 600°C for 3 hours.

[0079] <Preparation of ruthenium oxide supported catalyst>

[0080] After 5.0 g of the titanium dioxide carrier obtained above was impregnated with a solution prepared by dissolving 0.2 g of ruthenium chloride hydrate in 1.33 g of 1-propanol, it was dried in air at 100° C. for 4 hours. The dried solid was calcined at 350° C. for 3 hours in an electric furnace with air flow, and then slowly cooled to room temperature to finally obtain a ruthenium oxide catalyst having a ruthenium oxide content of 2.0 parts by weight. In addition, the outer surface loading degree of the ruthenium component measured by VMS was 0.32.

[0081] <Evaluation of Initial Activity of Ruthenium Oxide Supported Catalyst>

[0082] 0.3g of the above-obtained ruthenium oxide supported catalyst was diluted with 1.5g of α-alumina sol having a diameter of 2mm and filled into a quartz reaction tube (with an inner diameter of 8mm). In the reaction tube, the catalyst layer was heated to a temperature of 300°C, and hydrogen chloride and oxygen were supplied at a speed of 22.5mL / min at normal pressure to react. At a time point 2 hours after the reaction started, the gas at the outlet of the reaction tube was passed through a 15% potassium iodide aqueous solution to prepare a sample for 10 minutes. Then, the amount of chlorine generated was measured by iodine titration, thereby calculating the hydrogen chloride conversion rate using the following mathematical formula 2, and the results are shown in Table 1.

[0083] Mathematical formula 2

[0084]

[0085] Example 2

[0086] The initial activity evaluation was performed in the same manner as in Example 1, except that the temperature of the catalyst layer used was 283° C. for the catalyst obtained in Example 1. The results are shown in Table 1.

[0087] Example 3

[0088] 5.0 g of the carrier obtained in Example 1 was impregnated with a solution prepared by dissolving 0.067 g of ruthenium chloride hydrate in 0.44 g of 1-propanol, and then dried in air at 100 ° C for 4 hours. The above-mentioned loading method was repeated three times. The dried solid was calcined at 350 ° C for 3 hours in an electric furnace with air flow, and then slowly cooled to room temperature to finally obtain a ruthenium oxide catalyst with a ruthenium oxide content of 2.0 parts by weight. In addition, the outer surface loading degree of the ruthenium component measured by VMS was 1.

[0089] Initial activity evaluation was performed in the same manner as in Example 1. The results are shown in Table 1.

[0090] Example 4

[0091] <Preparation of Ruthenium Oxide Supported Catalyst>

[0092] 5.0 g of titanium dioxide powder was impregnated with a solution prepared by dissolving 0.2 g of ruthenium chloride hydrate in 1.05 g of 1-propanol, and then dried in air at 100° C. for 4 hours. The dried solid was calcined in an electric furnace at 350° C. for 3 hours in air, and then slowly cooled to room temperature, to finally obtain a ruthenium oxide catalyst having a ruthenium oxide content of 2.0 parts by weight.

[0093] <Evaluation of Initial Activity of Ruthenium Oxide Supported Catalyst>

[0094] 0.3g of the above-obtained ruthenium oxide supported catalyst was diluted with 0.6g of titanium dioxide powder and filled into a quartz reaction tube (with an inner diameter of 8mm). In the reaction tube, the catalyst layer was heated to a temperature of 250°C, and hydrogen chloride and oxygen were supplied at a speed of 22.5mL / min at normal pressure to react. At a time point 2 hours after the reaction started, the gas at the outlet of the reaction tube was passed through a 15% potassium iodide aqueous solution for 10 minutes of sample preparation. Then, the amount of chlorine generated was measured by iodine titration to calculate the hydrogen chloride conversion rate, and is shown in Table 2.

[0095] Comparative Example 1

[0096] The ruthenium oxide supported catalyst was prepared in the same manner as in Example 1, except that an aqueous solution prepared by dissolving 0.2 g of ruthenium chloride hydrate in 1.65 g of ultrapure water was used when preparing the ruthenium oxide supported catalyst. The external surface loading degree of the ruthenium component measured by VMS was 1. For the obtained ruthenium oxide supported catalyst, initial activity evaluation was performed in the same manner as in Example 1. The results are shown in Table 1.

[0097] Comparative Example 2

[0098] The ruthenium oxide supported catalyst was prepared in the same manner as in Example 4, except that an aqueous solution prepared by dissolving 0.2 g of ruthenium chloride hydrate in 1.3 g of ultrapure water was used when preparing the ruthenium oxide supported catalyst. The initial activity evaluation of the obtained ruthenium oxide supported catalyst was performed in the same manner as in Example 4. The results are shown in Table 2.

[0099] Comparative Example 3

[0100] The ruthenium oxide supported catalyst was prepared in the same manner as in Example 1, except that a solution prepared by dissolving 0.2 g of ruthenium chloride hydrate in 1.3 g of ethanol was used when preparing the ruthenium oxide supported catalyst. The external surface loading degree of the ruthenium component measured by VMS was 0.41. For the obtained ruthenium oxide supported catalyst, the initial activity evaluation was carried out in the same manner as in Example 1. The results are shown in Table 1.

[0101] Table 1

[0102]

[0103] Table 2

[0104]

[0105] Table 3

[0106]

[0107] It can be confirmed that the catalysts of Examples 1 to 4 in which propanol was used as a solvent for loading by changing the loading method had significantly lower S / R values ​​of the external surface loading degree, and were closer to 0, than those of Comparative Examples 1 to 3 in which ultrapure water or ethanol was used for loading. In addition, it can be confirmed that the conversion rate increased as the S / R value of the external surface loading degree decreased.

[0108] Therefore, it can be confirmed that the catalyst of the present invention, as a ruthenium oxide supported catalyst prepared using an alcohol organic solvent such as 1-propanol, can provide a catalyst containing ruthenium oxide only in the outer surface shell layer of a particle-shaped titanium dioxide carrier through a simplified process, and can further provide a highly active catalyst having a high hydrogen chloride conversion rate even at a relatively low reaction temperature, preferably around 250° C., in the chlorine production process. This is conducive to expanding the scale of the catalyst preparation process in the future.

[0109] The present invention has been described above through characteristic matters such as specific constituent elements and limited embodiments, but this is only used to help understand the present invention. The present invention is not limited to the above-mentioned multiple embodiments, and those skilled in the art can make various modifications and variations through such descriptions.

[0110] Therefore, the concept of the present invention is not limited to the embodiments described above, and the claims and their equivalents all belong to the scope of the concept of the present invention.

Claims

1. A method for preparing a ruthenium oxide supported catalyst, wherein the ruthenium oxide supported catalyst is a ruthenium oxide catalyst for chlorine production, comprising the following steps: Step (a), dissolving a ruthenium compound in 1-propanol to prepare a solution, and loading the solution onto one or more supports selected from titanium dioxide and aluminum oxide; Step (b), drying after the loading step; Step (c), after the drying step, firing, The VMS measurement value of the ruthenium oxide supported catalyst, i.e., S / R, is less than 0.5, wherein the VMS is a visual measurement system, and the outer surface loading degree of the ruthenium component is measured by VMS. In the mathematical formula S / R, R is the distance from any point A at the outermost edge of the horizontal cross section of the cylindrical catalyst to the center of the same horizontal cross section, and S is the distance from point A to point B where the ruthenium oxide component disappears measured on a straight line from the point A to the center of the same horizontal cross section. The ruthenium oxide supported catalyst is in particle form.

2. The method for preparing a ruthenium oxide supported catalyst according to claim 1, characterized in that: The specific surface area of ​​the titanium dioxide carrier in step (a) is 5 to 300 m 2 / g.

3. The method for preparing a ruthenium oxide supported catalyst according to claim 1, characterized in that: In the step (b), drying is performed under air conditions at 80 to 120° C. for 3 to 5 hours.

4. The method for preparing a ruthenium oxide supported catalyst according to claim 1, characterized in that: After the step (c), the finished product contains 5 parts by weight or less of ruthenium oxide relative to 100 parts by weight of the total weight of the catalyst.

5. The method for preparing a ruthenium oxide supported catalyst according to claim 1, characterized in that: In the step (c), the sintered product is fired at 300 to 400° C. for 2 to 4 hours and then cooled to room temperature.

6. The method for preparing a ruthenium oxide supported catalyst according to claim 1, characterized in that: The ruthenium oxide supported catalyst is used to oxidize hydrogen chloride to prepare chlorine.

7. The method for preparing a ruthenium oxide supported catalyst according to claim 1, characterized in that: After the loading step, the ruthenium oxide supported catalyst has 70 to 80 parts by weight of the support, less than 5 parts by weight of the ruthenium compound, and 15 to 25 parts by weight of the 1-propanol relative to 100 parts by weight of the dry pre-catalyst.

8. A ruthenium oxide supported catalyst, characterized in that Prepared by the preparation method according to any one of claims 1 to 7, The VMS measurement value of the ruthenium oxide supported catalyst, i.e., S / R, is less than 0.

5. The ruthenium oxide supported catalyst is in particle form.

9. A method for producing chlorine based on the oxidation of hydrogen chloride, characterized in that: The method is carried out in the presence of a catalyst prepared by the method according to any one of claims 1 to 7.

10. The method for producing chlorine based on oxidation of hydrogen chloride according to claim 9, characterized in that: In the chlorine production method, the reaction temperature is 200-300°C.

Images