JP2008093663A - Manufacturing method of aromatization catalyst of lower hydrocarbon - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an aromatization catalyst of a lower hydrocarbon for stabilizing and further enhancing a production rate of hydrogen and an aromatic compound when aromatizing the lower hydrocarbon. <P>SOLUTION: A manufacturing method of the aromatization catalyst of the lower hydrocarbon for obtaining the catalyst by treating in a mixed gas with a reductive gas when carbonizing after carrying molybdenum and a metal constituent other than molybdenum on a metalo silicate comprises making the metalo silicate molybdenum and the metal constituent carry in separate carrying processes. For example, to make the metalo silicate separately carry a molybdenum constituent and the metal constituent, the molybdenum constituent is got carried after getting the metal constituent carried by the metalo silicate. Otherwise, the metal constituent is got carried after getting the molybdenum constituent carried by the metalo silicate. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to advanced utilization of natural gas, biogas, and methane hydrate mainly composed of methane.

  Natural gas, biogas, and methane hydrate are considered to be the most effective energy as a countermeasure against global warming, and there is an increasing interest in their utilization technologies. Taking advantage of its cleanliness, methane resources are attracting attention as new next-generation organic resources and hydrogen resources for fuel cells, but the present invention uses benzene and naphthalene, which are raw materials for chemical products such as plastics from methane. The present invention relates to a catalytic chemical conversion technique capable of efficiently producing an aromatic compound as a main component and high-purity hydrogen gas and a method for producing the catalyst.

  As a method of co-producing an aromatic compound such as benzene and hydrogen from lower hydrocarbons, particularly methane, a method of reacting methane in the presence of a catalyst and in the absence of oxygen or an oxidizing agent is known. For example, according to Non-Patent Document 1 (JOURNAL OF CATALYSIS (1997)), a catalyst in which molybdenum is supported on ZSM-5 is effective as the catalyst. However, even when these catalysts are used, there are problems that carbon deposition is large and methane conversion is low.

Therefore, a catalyst in which molybdenum or the like is supported on a porous metallosilicate has been proposed (for example, Patent Document 1 (Japanese Patent Laid-Open No. 10-272366) and Patent Document 2 (Japanese Patent Laid-Open No. 11-60514)). According to these publications, a porous metallosilicate having a 7 Å strong pore diameter is adopted as a carrier, and a catalyst material is supported on the porous metallosilicate. According to experiments using this catalyst, it has been confirmed that lower hydrocarbons are efficiently aromatized, and accompanying this, high-purity hydrogen can be obtained. In particular, Patent Document 2 describes that the characteristics of the catalyst are improved by adding not only molybdenum but also metals other than molybdenum as the second component.
JOURNAL OF CATALYSIS, 1997, pp. 165, pp. 150-161 JP-A-10-272366 (paragraph numbers (0008) to (0013) and (0019)) JP 11-60514 A (paragraph numbers (0007) to (0011) and (0020))

  However, even today, in order to further increase the production efficiency of aromatic compounds and hydrogen, it is desired to develop even better catalysts. In particular, in the prior art, the production rate of hydrogen and aromatic compounds is not stable at present.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a lower hydrocarbon aromatic which can stably and further improve the production rate of hydrogen and an aromatic compound when a lower hydrocarbon is aromatized. It is in providing the manufacturing method of a catalyst.

  Therefore, a method for producing a lower hydrocarbon aromatization catalyst for solving the above-mentioned problem is that a metallosilicate is loaded with molybdenum and a metal component other than molybdenum, and then mixed with a reducing gas when carbonized. In the method for producing a lower hydrocarbon aromatization catalyst obtained by treatment, molybdenum and the metal component are supported on the metallosilicate in separate supporting steps. According to the aromatization catalyst for lower hydrocarbons obtained by this production method, the activity of producing aromatic compounds, particularly polyphthalic aromatic compounds, naphthalene, was obtained by conventional methods (molybdenum single supported catalyst or molybdenum It has been found that this is an improvement over two-component simultaneous supported catalysts. In addition, as a 2nd metal component, there exists an iron group element, For example, cobalt, iron, nickel, etc. are mentioned.

  In the method for producing a lower hydrocarbon aromatization catalyst, a method of supporting molybdenum and a second metal component on the metallosilicate by separate supporting steps is a method of supporting the second metal component before supporting molybdenum. And the second metal component are supported after supporting molybdenum and the catalytic activity of the lower hydrocarbon aromatization catalyst obtained by either method is the conventional one (molybdenum single supported catalyst or It has been found that the catalyst is improved and stable even when compared to a molybdenum / second metal component simultaneous supported catalyst).

  The solution concentration of the metal component used for individually supporting molybdenum and the second metal component is 0.01 to 0.2 mol / l, more preferably 0.01 to 0.1 mol / l as a metal salt concentration. If the amount is larger than this range, the supported amount exceeds the amount of molybdenum and the cost increases. If the concentration is lower than this range, the effect of the added metal is hardly obtained.

  Examples of the reducing gas include a gas containing a lower hydrocarbon such as methane, ethane, and butane and argon, a gas containing the lower hydrocarbon and hydrogen, a hydrogen gas, or an ammonia gas. In addition, when the metallosilicate is subjected to carbonization in the above production method, these metal elements or other metal elements such as iron group element components may be appropriately combined and supported.

  As the metallosilicate used in the process for producing the lower hydrocarbon aromatization catalyst of the present invention, for example, in the case of aluminosilicate, a porous body having pores having a diameter of 4.5 to 6.5 angstroms composed of silica and alumina Molecular sieve 5A, faujasite (NaY and NaX), ZSM-5, MCM-22, etc. are exemplified. In addition, a porous body composed of 6 to 13 angstrom micropores such as ALPO-5 and VPI-5 mainly composed of phosphoric acid, a zeolite carrier composed of channels, silica and a part of alumina as a component. Examples thereof include mesoporous porous carriers such as FSM-16 and MCM-41 having cylindrical pores (channels) having mesopores (10 to 1000 angstroms). In addition to the above-mentioned alumina silicate, metallosilicates composed of silica and titania are also included.

  The lower hydrocarbon aromatization catalyst obtained by the production method of the present invention is used in the form of powder, rod, hollow cylinder, pellet, honeycomb, ring or other shapes. In order to process the metallosilicate into the shape, for example, an inorganic binder such as clay or an inorganic filler such as glass fiber may be blended in an amount of 15 to 25% by weight with respect to the metallosilicate.

  Therefore, according to the method for producing a lower hydrocarbon aromatization catalyst according to the above-described invention, when the lower hydrocarbon is aromatized, the production rate of hydrogen and the aromatic compound can be improved stably. A hydrocarbon aromatization catalyst can be provided.

  Embodiments of the present invention will be described with reference to the drawings.

  A method for producing a lower hydrocarbon aromatization catalyst according to an embodiment of the present invention will be described.

  The lower hydrocarbon aromatization catalyst of the present invention (hereinafter referred to as catalyst in the present embodiment) is formed by blending an inorganic component obtained by blending a metallosilicate with other inorganic filler together with an organic binder and moisture, Drying and firing to obtain a fired body, and individually carrying molybdenum and a metal component other than molybdenum (hereinafter referred to as a second metal component) on the fired body, followed by carbonizing by mixing a reducing gas It is gained in. The step of individually supporting molybdenum and the second metal component includes either a method of supporting the second metal component before supporting molybdenum, or a method of supporting the second metal component after supporting molybdenum. The combustion temperature after supporting the second metal component in the individual support is preferably 400 to 600 ° C. In addition, as a 2nd metal component, there exists an iron group element, For example, cobalt, iron, nickel, etc. are mentioned.

  As the metallosilicate, for example, in the case of aluminosilicate, it is a porous body having pores with a diameter of 4.5 to 6.5 angstroms made of silica and alumina, and includes molecular sieve 5A, faujasite (NaY and NaX), ZSM-5, MCM-22, etc. are exemplified. Furthermore, a porous body composed of 6 to 13 angstrom micropores such as ALPO-5, VPI-5, etc. mainly composed of phosphoric acid, a zeolite carrier composed of channels, silica and a part of alumina as a component. Examples thereof include mesoporous porous carriers such as FSM-16 and MCM-41 having cylindrical pores (channels) having mesopores (10 to 1000 angstroms). In addition to the alumina silicate, a metallosilicate composed of silica and titania may be used.

  Examples of the inorganic filler include inorganic binders such as clay and reinforcing inorganic materials such as glass fibers, and are blended in an amount of 15 to 25% by weight based on the total inorganic components of the catalyst. The organic binder may be a known one as long as it can be molded by kneading the metallosilicate and the inorganic filler together with moisture.

A high-pressure molding method is employed for molding after blending the above materials. The catalyst support for aromatizing the hydrocarbon is usually used in the form of a fluidized bed catalyst using particles having a particle size of several μm to several hundred μm. Conventionally, such a catalyst is obtained by mixing a catalyst carrier with an organic binder, an inorganic binder and water to form a slurry and granulating it with a spray dryer, followed by firing. In this case, since the molding pressure is small, it is necessary to add about 40 to 60% by weight of clay added as a firing aid to ensure firing strength. In the molding process in the production process of the catalyst of the present invention, by using a high pressure molding method, the amount of inorganic binder such as clay is reduced to 15 to 25% by weight in the catalyst, that is, the metallosilicate component in the catalyst is 75 to 85%. The catalyst activity can be increased up to% by weight, and the substantial catalytic activity is higher than that of the catalyst obtained by granulation with a spray dryer. Specific examples of the high pressure molding method include a vacuum extrusion molding machine. Moreover, it is good to set the extrusion pressure at this time in the range of 70-100 kg / cm < ² >. In addition, the shape of the molded body is formed into a hollow cylindrical shape, a pellet shape, a honeycomb shape, a ring shape, or other shapes in addition to a powder shape or a rod shape according to the usage form of the catalyst.

  What is necessary is just to dry the obtained molded object for a suitable temperature fixed time so that the water | moisture content added at the time of shaping | molding can be removed. In addition, the firing is performed at 30 to 50 ° C./hour for both temperature increase and temperature decrease rates. At this time, it is advisable to carry out temperature keeping for about 2 to 5 hours twice in a temperature range of 250 to 450 ° C. so that the blended organic binder does not burn instantaneously. This is because the temperature rise and temperature drop rate for removing the binder is equal to or higher than the above rate, and when the keep time for removing the binder is not secured, the binder burns instantaneously and the strength of the fired body is reduced. The firing temperature may be in the range of 725 to 800 ° C. This is because when the carrier is a molded body, the strength is lowered at 700 ° C. or lower, and the characteristics are lowered at 800 ° C. or higher.

  Next, in supporting the metal component on the obtained fired body, the inventors have also studied a method for supporting molybdenum, and applied for an invention related to this in Japanese Patent Application No. 2002-260706. In the case of impregnation, an ammonium molybdate aqueous solution is used.

  Also in the process of supporting the second metal component in the production of the lower hydrocarbon aromatization catalyst according to the present embodiment, the chloride, nitrate, ammonium salt, etc. of the second metal component element may be used. At this time, the molybdenum loading may be, for example, 6% by weight with respect to the carrier. The second metal component may be in a molar ratio of, for example, a ratio of second metal element: molybdenum = 0.2: 1. The molybdenum loading and the molar ratio between the second metal component and molybdenum are not limited to this and are adjusted as appropriate. The molybdenum impregnated in the fired body and the metal component are supported on the fired body as oxides by oxidation treatment at a constant temperature and time.

  When the catalyst precursor obtained by the oxidation treatment of the impregnated fired body is carbonized, not the reaction gas (reducing gas) atmosphere composed of methane gas and argon gas based on the conventional carbonization treatment but other reductions Alternatively, a heat treatment may be performed at a temperature of 350 to 750 ° C. for 2 to 24 hours. Examples of the reducing gas include gas containing methane and hydrogen, hydrogen gas, or ammonia gas. The illustrated reducing gases may be used in appropriate combination. Furthermore, you may combine the methane gas and argon gas which are provided to the said conventional carbonization processing method.

  The catalyst produced as described above is tangible because the pressure molding method is adopted as described above, and is mainly packed in a fixed bed type reactor. Then, by providing a gas containing a lower hydrocarbon to this reactor and causing the catalyst to contact with the catalyst under a constant temperature, pressure, space velocity and residence time, the aromatic compound at a stable production rate can be obtained. Hydrogen can be produced. Examples of the lower hydrocarbon include methane, ethane, ethylene, propane, propylene, n-butane, isobutane, n-butene, and isobutene.

EXAMPLES Next, although an Example demonstrates this invention further more concretely, this invention is not limited at all by these Examples.
1. Production of lower hydrocarbon aromatization catalyst Ammonium-type ZSM-5 (SiO ₂ / Al ₂ O ₃ = 25-60) is adopted as the metallosilicate, which is the main component of the catalyst, and this is used as an organic compound with other inorganic components. The mixture was kneaded with a binder, formed, dried and fired, then impregnated with a metal component, and then subjected to oxidation and carbonization treatment to obtain a lower hydrocarbon aromatization catalyst (hereinafter referred to as catalyst). Below, each process of manufacture of the catalyst which concerns on a comparative example and an Example is demonstrated.

(Comparative example 1) Molybdenum single carrying | supporting The catalyst which concerns on the comparative example 1 carry | supports only molybdenum. The manufacturing process is shown below.

1) Compounding of catalyst component The components of the catalyst and the compounding ratio (wt%) are shown below.

Inorganic component: Organic binder: Moisture = 65.4: 13.6: 21.0
Moreover, it showed below the component of an inorganic component, and its mixture ratio (weight%).

ZSM-5: Clay: Glass fiber = 82.5: 10.5: 7.0
2) Molding An inorganic component, an organic binder, and moisture were blended in the above ratio and kneaded by a kneading means such as a kneader. Next, this mixture was formed into a rod shape (diameter 5 mm) by a vacuum extrusion molding machine. The molding pressure at this time was set to 70 to 100 kg / cm ² . Then, a rod-shaped carrier having a diameter of 5 mm obtained by this extrusion molding was cut into a length of 6 mm to obtain a molded body.

  3) Drying and calcination In order to remove moisture added during molding, the molded body was dried for about 5 hours while controlling temperature and humidity at 100 ° C. and then baked. The firing temperature was in the range of 725 to 800 ° C. The temperature increase and temperature decrease rates were both 30 to 50 ° C./hour. In order to prevent the organic binder from burning instantaneously during firing, the binder component was removed by carrying out a temperature keep of about 2 to 5 hours under a temperature range of 250 to 450 ° C. twice.

  4) Impregnation The obtained fired body was immersed in an aqueous ammonium molybdate solution, and the fired body was impregnated with a molybdenum component. The amount of molybdenum supported was 6% by weight based on the weight of the sintered body.

  5) Oxidation treatment In order to decompose and oxidize the metal salt impregnated in the calcined body to obtain molybdenum oxide, it was calcined at 550 ° C. for 10 hours to obtain a catalyst precursor.

6) Carbonization treatment Based on the conventional carbonization treatment method of the catalyst precursor. The catalyst precursor impregnated with only molybdenum and oxidized was heated to 700 ° C. under an air atmosphere, and this state was maintained for 2 hours. Then, the atmosphere was switched to a reaction gas (reducing gas) of 9CH ₄ + Ar, The temperature was raised to 750 ° C. Thus, a catalyst according to Comparative Example 1 carrying only molybdenum was obtained.

(Comparative Example 2) Molybdenum / cobalt simultaneous support The catalyst according to Comparative Example 2 is the same as the catalyst manufacturing process according to Comparative Example 1 except for the impregnation step and the oxidation treatment step. Manufactured with.

  Impregnation The fired body obtained in the steps 1) to 3) was immersed in an aqueous ammonium molybdate solution to which cobalt nitrate was added, and the sintered body was impregnated with a molybdenum component and a cobalt component. The molybdenum loading was 6% by weight with respect to the weight of the sintered body, and the cobalt loading was a molar ratio of cobalt: molybdenum = 0.2: 1.

  Oxidation treatment In order to decompose and oxidize the metal salt impregnated in the calcined body to make molybdenum oxide, it was calcined at 550 ° C. for 5 hours to obtain a catalyst precursor.

  Then, the catalyst precursor was subjected to the carbonization treatment to obtain a catalyst according to Comparative Example 2 in which molybdenum and cobalt were simultaneously supported.

(Example 1) Cobalt pre-supporting The catalyst according to Example 1 was obtained by separately supporting molybdenum and cobalt, in particular, firstly supporting the cobalt component and then supporting the molybdenum component. The catalyst was produced by the same method as the catalyst production process according to Comparative Example 1 except for the impregnation / oxidation process consisting of the following steps a) to d).

  A) After the fired body obtained in the steps 1) to 3) is immersed in an aqueous cobalt nitrate solution having a concentration of 0.05 mol / l to impregnate the sintered body with a cobalt component, the sintered body is heated to 100 ° C. to 120 ° C. Dry in range to remove moisture.

  A) The cobalt-impregnated fired body after drying was fired in air at a temperature of 400 to 600 ° C. to obtain a cobalt-supported fired body.

  C) This cobalt-supported fired body was immersed in an aqueous ammonium molybdate solution so that the molybdenum support amount was 6% by weight. The fired body was impregnated with a molybdenum component, and then dried while controlling the humidity and temperature.

  D) The dried molybdenum-impregnated cobalt-supported calcined product was dried in air at 550 ° C. for 5 hours to obtain a catalyst precursor.

  And this catalyst precursor was used for the said carbonization process, and the catalyst which concerns on Example 1 which carry | supported molybdenum and cobalt was obtained.

(Example 2) Cobalt post-carrying The catalyst according to Example 2 was obtained by individually carrying molybdenum and cobalt, and in particular, obtained by first carrying a molybdenum component and then carrying a cobalt component. The catalyst was produced by the same method as the catalyst production process according to Comparative Example 1 except for the impregnation / oxidation process consisting of the following steps a) to d).

  A) The fired body obtained in the steps 1) to 3) is immersed in an aqueous ammonium molybdate solution so that the molybdenum loading is 6% by weight, and the fired body is impregnated with a molybdenum component. Drying while controlling the temperature.

  A) The dried molybdenum-impregnated fired body was fired in air at a temperature of 400 to 600 ° C. to obtain a molybdenum-supported fired body.

  C) This molybdenum-supported fired body was immersed in a cobalt nitrate aqueous solution having a concentration of 0.05 mol / l to impregnate the sintered body with a cobalt component, and then dried in the range of 100 ° C. to 120 ° C. to remove moisture. .

  D) The cobalt-impregnated molybdenum-supported calcined product after drying was calcined in air at 550 ° C. for 5 hours to obtain a catalyst precursor.

And this catalyst precursor was used for the said carbonization process, and the catalyst which concerns on Example 2 which carry | supported molybdenum and cobalt was obtained.
2. Evaluation of catalyst The evaluation method of the catalyst which concerns on a comparative example and an Example is described.

Inconel 800H gas contact part calorizing treatment reaction tube (inner diameter 18 mm) of a fixed bed flow type reactor was filled with 14 g of the catalyst to be evaluated (zeolite ratio 82.50%). Then, a mixed gas containing methane and hydrogen (methane + 10% argon + 6% hydrogen) was supplied thereto, and the reaction space velocity was 3000 ml / g-MFI / h (CH ₄ gas flow base), the reaction temperature was 750 ° C., The catalyst and the mixed gas were reacted under the conditions of a reaction time of 10 hours and a reaction pressure of 0.3 MPa. At this time, the rate of formation of hydrogen and aromatic compounds (benzene, toluene, naphthalene) was examined over time.

  FIG. 1 shows the change over time in the hydrogen production rate when the catalysts according to Comparative Example 1 and Comparative Example 2 are used, and FIG. 2 shows the hydrogen production rate when the catalysts according to Example 1 and Example 2 are used. This shows the change over time.

  Comparing the change in the hydrogen production rate shown in FIG. 1 and FIG. 2, the catalytic activity of the catalysts according to Example 1 and Example 2 (cobalt pre-supported and cobalt post-supported cobalt / molybdenum) is shown in Comparative Example 1. It can be confirmed that the catalyst is more stable than the catalyst according to Comparative Example 2 (molybdenum alone supported and cobalt / molybdenum simultaneously supported).

  FIG. 3 shows the change over time in the production rate of benzene when the catalysts according to Comparative Examples 1 and 2 are used, and FIG. 4 is the production rate of benzene when the catalysts according to Examples 1 and 2 are used. This shows the change over time.

  As is apparent from the comparison of changes in the benzene production rate shown in FIGS. 3 and 4, the initial activity of the catalysts according to Comparative Example 2, Example 1 and Example 2 is improved as compared with that of the catalyst according to Comparative Example 1. In particular, the initial activity of the catalysts according to Example 1 and Example 2 is remarkably improved.

  Moreover, the time-dependent change in the production rate of toluene when the catalysts according to Comparative Example 1 and Comparative Example 2 are used, and the time-dependent change in the production rate of toluene when the catalysts according to Example 1 and Example 2 are used. And investigated.

  Although not shown, when the toluene production rate changes in these comparative examples and examples are compared, the tendency tends to be the same as the comparison result of the benzene production rates shown in FIG. 3 and FIG. It was confirmed that the catalyst obtained by separately supporting cobalt and molybdenum according to the present invention has significantly improved initial activity, and in particular, the stability of the catalyst activity of the catalyst according to Example 1 has been improved.

  Furthermore, the change with time of the formation rate of naphthalene when the catalysts according to Comparative Example 1 and Comparative Example 2 are used, and the change with time of the formation rate of naphthalene when the catalysts according to Examples 1 and 2 are used. I also investigated.

  Although not shown, when the change in the naphthalene production rate of these comparative examples and examples is compared, the initial production rates of the catalysts according to Examples 1 and 2 are 2 to 2 compared with those of the catalysts according to Comparative Examples 1 and 2. A three-fold significant improvement in activity was experimentally confirmed.

  Based on the above results, Table 1 shows conventional catalysts for the production of hydrogen, benzene, toluene, and naphthalene by the catalysts according to Comparative Example 1, Comparative Example 2, Example 1, and Example 2 (Comparative Example 1). The standard ("△") was used, and "○" indicates that both initial activity and stability were effective, and "◎" indicates that both initial activity and stability were significantly effective. Is.

  The lower hydrocarbon aromatization catalyst of the present invention has been described in detail on the basis of the above-described examples, but it is understood by those skilled in the art that this example can be variously modified and modified within the scope of the technical idea of the present invention. Obviously, such variations and modifications fall within the scope of the appended claims.

  The catalyst of this example employs molybdenum as the main supported metal, but the effect as already confirmed, rhenium and tungsten among various catalyst metals introduced in the literature introduced in the above embodiment, and further Even when these (including molybdenum) compounds are used alone or in combination, it has been confirmed that similar effects can be obtained. Further, even if the second metal component supported separately from molybdenum employs iron or nickel which is an iron group element other than molybdenum, the same effect can be obtained.

  Further, in this example, only the drying method of the support on which the catalyst metal is supported by the impregnation method is shown. However, when applied to the support on which the catalyst metal is supported by the ion exchange method, a sublimable compound is used. Thus, it has been confirmed that similar effects can be obtained even when vapor deposition is carried on a carrier.

  Furthermore, although the catalyst according to the example is formed in a rod shape, it is confirmed that the same effect can be obtained even in the case of forming a hollow cylindrical shape, honeycomb shape, powder shape, pellet shape, ring shape. Has been.

Changes over time in the hydrogen generation rate when the catalysts according to Comparative Example 1 and Comparative Example 2 were used. Changes over time in the hydrogen generation rate when the catalysts according to Example 1 and Example 2 were used. The time-dependent change of the production | generation rate of benzene at the time of using the catalyst which concerns on the comparative example 1 and the comparative example 2. FIG. The time-dependent change of the production | generation rate of benzene at the time of using the catalyst which concerns on Example 1 and Example 2. FIG.

Claims (6)

  A method for producing a lower hydrocarbon aromatization catalyst obtained by supporting molybdenum and a metal component other than molybdenum on a metallosilicate and then mixing and processing a reducing gas when carbonizing the metal component. A process for producing a lower hydrocarbon aromatization catalyst, wherein a metallosilicate is loaded with molybdenum and the metal component in separate loading steps.   2. The lower hydrocarbon aroma according to claim 1, wherein when the molybdenum component and the metal component are separately supported on the metallosilicate, the molybdenum component is supported after the metal component is supported on the metallosilicate. A method for producing a grouping catalyst.   2. The lower hydrocarbon fragrance according to claim 1, wherein when the molybdenum component and the metal component are individually supported on the metallosilicate, the metal component is supported after the molybdenum component is supported on the metallosilicate. A method for producing a grouping catalyst.   The solution concentration of the metal component provided when the molybdenum component and the metal component are individually supported on the metallosilicate is 0.01 to 0.2 mol / l as a metal salt concentration. 4. A process for producing a lower hydrocarbon aromatization catalyst according to any one of 1 to 3.   The method for producing a lower hydrocarbon aromatization catalyst according to any one of claims 1 to 4, wherein the metal component is an iron group element.   6. The method for producing a lower hydrocarbon aromatization catalyst according to claim 5, wherein the iron group element is iron, cobalt, or nickel.

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