JP2012120977A - Method of manufacturing siliceous solid catalyst, and method of manufacturing lower hydrocarbon - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a siliceous solid catalyst having high mechanical strength and superior catalytic performance.SOLUTION: The method of manufacturing the siliceous solid catalyst includes a kneading step for kneading a mixture of a siliceous solid and a compound containing an alkali earth metal and aluminum, and water. The siliceous solid catalyst is obtained by molding and firing the obtained kneaded body. In the kneading step, the mixture and water are kneaded under the existence of anions forming a water soluble salt with the alkali earth metal and forming a water soluble salt also with the aluminum.

Description

  The present invention relates to a method for preparing a siliceous solid catalyst used in a step of synthesizing a lower hydrocarbon from dimethyl ether and / or methanol, and a method for producing a lower hydrocarbon using the catalyst.

  The zeolite catalyst is either dimethyl ether (hereinafter sometimes abbreviated as “DME”) or methanol, or a reaction for synthesizing lower hydrocarbons from dimethyl ether and methanol (DTO (Dimethylether to Olefin) reaction), or MTO. (Methanol to Olefin) reaction, gasoline synthesis reaction using methanol as a raw material MTG (Methanol to Gasoline) reaction, fluid catalytic cracking (FCC), and structure of linear olefin to its corresponding methyl branched isoolefin It is used in many processes such as isomerization reaction.

  In particular, when a zeolite catalyst is used in a process for producing propylene from a raw material mixture containing an olefin having 4 or more carbon atoms and methanol and / or dimethyl ether, propylene can be obtained in a high yield.

  As a method for producing a zeolite catalyst, for example, a zeolite powder, an alumina-containing binder, water and an acid are mixed to obtain a zeolite / alumina mixture. The mixture is further kneaded and then pelletized. A method of baking at ˜700 ° C. is known (for example, see Patent Document 1). This zeolite catalyst can be used as a catalyst for the structural isomerization of linear olefins to methyl branched isoolefins as described above.

  As a method for producing a zeolite catalyst, for example, a method is known in which a zeolite having a Si / Al molar ratio of 10 or more and 300 or less is mixed with an alkaline earth metal compound (see, for example, Patent Document 2). . This zeolite catalyst can be used as a catalyst for the above-mentioned DTO reaction and MTO reaction. According to this production method, the precipitation of carbonaceous matter on the catalyst surface during the reaction is suppressed, and the catalyst in these reactions It is said that a zeolite catalyst with improved water vapor resistance and catalyst life can be obtained.

  When a catalyst is used in a continuous process for industrial large-scale production of lower hydrocarbons, a large amount of catalyst is charged into a reactor, and therefore it is desired to produce a large amount of catalyst efficiently. Furthermore, the filling of a solid catalyst such as a zeolite catalyst is generally filled into the reactor from above the reactor. Further, in a continuous process of industrial large-scale production of lower hydrocarbons, if a reaction is continuously performed for a long time, a carbon component may adhere to the catalyst. At that time, an operation (catalyst regeneration operation) is generally performed in which a gas containing oxygen is supplied into the reactor to burn and remove the carbon component on the catalyst surface filled in the reactor. For this reason, it is desired that the solid catalyst such as a zeolite catalyst has sufficient mechanical strength that does not cause destruction at the time of filling or thermal vibration of the catalyst in a reaction for producing propylene or a catalyst regeneration operation. .

  However, the zeolite catalyst produced by the method as described above is brittle with catalyst particles, so the catalyst may be destroyed or powdered by impact at the time of catalyst filling. As a result, desired catalyst activity and yield can be obtained. There may not be. Further, in the reaction for producing propylene or the catalyst regeneration operation, there is a concern that the catalyst is destroyed by thermal vibration of the catalyst in the reactor.

JP 2006-225399 A JP 2008-080301 A

  The present invention provides a siliceous solid catalyst having higher mechanical strength and excellent catalytic performance.

As a result of intensive studies to solve the above-mentioned problems, the present inventors further added an acid aqueous solution during the kneading of zeolite powder, alkaline earth metal-containing compound, alumina-containing binder, and water in the step of producing a zeolite catalyst. Surprisingly, it has been found that the strength of the resulting catalyst, particularly the crushing strength, is dramatically improved.
The present invention has been achieved on the basis of such findings, and the following [1] to [13] are summarized.

[1] A kneading step of kneading a mixture containing a siliceous solid, an alkaline earth metal, and an aluminum-containing compound and water, molding the obtained kneaded material, and calcining the siliceous solid catalyst. In the method for producing a siliceous solid catalyst to be obtained, in the kneading step, the mixture and water are formed in the presence of an anion that forms a water-soluble salt with an alkaline earth metal and also forms a water-soluble salt with aluminum. A method for producing a siliceous solid catalyst, characterized by kneading.

[2] The method for producing a siliceous solid catalyst according to [1], wherein the siliceous solid contains silica.

[3] The method for producing a siliceous solid catalyst according to [1] or [2], wherein the siliceous solid is zeolite.

[4] The method for producing a siliceous solid catalyst according to any one of [1] to [3], wherein an alkaline earth metal is contained in the skeleton of the siliceous solid.

[5] The siliceous material according to any one of [1] to [4], wherein the mixture is a mixture containing a siliceous solid, an alkaline earth metal-containing compound, and an aluminum-containing compound. A method for producing a solid catalyst.

[6] The method for producing a siliceous solid catalyst according to any one of [1] to [5], wherein the alkaline earth metal-containing compound is a calcium-containing compound.

[7] The kneading step is a step of kneading the mixture, water, and an acid, and the acid is composed of the anion and a hydrogen ion. The manufacturing method of the siliceous solid catalyst as described in any one of Claims.

[8] The method for producing a siliceous solid catalyst according to [7], wherein the acid is one or both of nitric acid and hydrochloric acid.

[9] The method for producing a siliceous solid catalyst according to any one of [1] to [6], wherein a water-soluble salt composed of a metal ion and the anion is blended with the mixture. .

[10] The method for producing a siliceous solid catalyst according to [9], wherein the metal ions are alkaline earth metal ions or aluminum ions.

[11] The method for producing a siliceous solid catalyst according to any one of [1] to [10], wherein in the kneading step, the water content of the kneaded product is 25 to 30%. .

[12] The method for producing a siliceous solid catalyst according to any one of [1] to [11], wherein in the kneading step, the temperature of the kneaded product is 10 to 50 ° C.

[13] Lower carbonization for synthesizing a lower hydrocarbon using one or both of dimethyl ether and methanol as a raw material using the siliceous solid catalyst obtained by the method according to any one of [1] to [12] A method for producing hydrogen.

  According to the present invention, a siliceous solid catalyst having higher mechanical strength and excellent catalytic performance can be provided.

  The method for producing a siliceous solid catalyst of the present invention includes a kneading step of kneading a mixture containing siliceous solid, alkaline earth metal and aluminum-containing compound with water. Examples of such a mixture include a mixture containing a siliceous solid, an alkaline earth metal-containing compound, and an aluminum-containing compound, and a mixture containing a siliceous solid containing an alkaline-earth metal in the skeleton and an aluminum-containing compound. Can be mentioned.

  The siliceous solid is a powder of a silicon compound that may contain other metals or other elements. One or more siliceous solids may be used. Examples of such a siliceous solid include silica, and examples of such silica include silicates such as silicate oxide, silicate composite oxide, silicate gel, and silicate glass. Examples include powder and clay minerals. Examples of the silicate complex oxide include zeolite and feldspar.

  A siliceous solid containing an alkaline earth metal in the skeleton is a kind of siliceous solid, and is a siliceous solid containing an alkaline earth metal as another metal. The siliceous solid containing the alkaline earth metal in the skeleton may be one kind or two or more kinds. Examples of the siliceous solid containing an alkaline earth metal in the skeleton include zeolite containing an alkaline earth metal in the skeleton. Examples of the zeolite containing an alkaline earth metal in the skeleton include an alkaline earth metal-containing MFI. Structural zeolites are mentioned.

  The average primary particle size of the siliceous solid is 0 from the viewpoint of increasing the dispersibility at the time of kneading and the reactivity when used as a catalyst, and from the viewpoint of preventing problems in handling such as filtration during the production of the catalyst. The thickness is preferably 0.01 to 100 μm, more preferably 0.05 to 10 μm, and still more preferably 0.1 to 3 μm.

The composition of the zeolite can be determined according to the application of the catalyst. For example, in the case of a catalyst for a process for producing propylene from a raw material mixture containing an olefin having 4 or more carbon atoms and methanol and / or dimethyl ether, the zeolite silica / alumina ratio (SiO ₂ / Al ₂ O ₃ molar ratio) Is usually 10 or more, preferably 150 or more, more preferably 300 or more, and still more preferably 700 or more.

  Alkaline earth metal-containing compounds include salts of alkaline earth metals that may contain other metals. The alkaline earth metal-containing compound may be one kind or two or more kinds.

  The particle size of the alkaline earth metal-containing compound is preferably 10 μm or less, more preferably 1 μm or less in the kneaded material, from the viewpoint that the smaller one is more easily dispersed in the mixture during molding. More preferably, it is 1 μm or less.

Examples of the alkaline earth metal-containing compound include magnesium carbonate (MgCO ₃ ), magnesium hydroxide (Mg (OH) ₂ ), magnesium oxide (MgO), magnesium acetate ((CH ₃ COO) ₂ Mg), and magnesium nitrate. (Mg (NO ₃ ) ₂ ), magnesium aluminate (MgAl ₂ O ₄ ), magnesium orthosilicate (Mg ₂ SiO ₄ ), calcium carbonate (CaCO ₃ ), calcium hydroxide (Ca (OH) ₂ ), calcium oxide ( CaO), calcium acetate ((CH ₃ COO) ₂ Ca), calcium nitrate (Ca (NO ₃ ) ₂ ), calcium aluminate (CaAl ₂ O ₄ ), calcium orthosilicate (Ca ₂ SiO ₄ ), strontium carbonate (SrCO) _3), strontium hydroxide (Sr (OH) _2), strontium oxide (SrO), Strontium _{((CH 3 COO) 2 Sr} ), strontium nitrate _{(Sr (NO 3) 2)} , strontium aluminate (SrAl ₂ O _4), strontium silicate, barium carbonate (BaCO _3), barium hydroxide (Ba (OH ₂ ), barium oxide (BaO), barium acetate ((CH ₃ COO) ₂ Ba), barium nitrate (Ba (NO ₃ ) ₂ ), barium aluminate (BaAl ₂ O ₄ ), and barium silicate.

  The alkaline earth metal-containing compound is preferably a calcium-containing compound from the viewpoint of suppressing the elimination of active sites during the reaction for producing propylene or the catalyst regeneration operation and extending the life of the catalyst. Examples of such calcium-containing compounds include calcium carbonate, calcium hydroxide, calcium oxide, calcium acetate, calcium nitrate, calcium aluminate, and calcium orthosilicate.

  As the aluminum-containing compound, a compound that binds to a siliceous solid by firing can be used. The aluminum-containing compound may be one type or two or more types.

  The particle diameter of the aluminum-containing compound is preferably 20 μm or less, more preferably 1 μm or less, and further preferably 0.1 μm or less in the kneaded product from the viewpoint of dispersibility during kneading. .

Examples of the aluminum-containing compound include aluminum oxide and aluminum hydroxide. For example, γ-alumina (Al ₂ O ₃ ), boehmite (AlO (OH)), aluminum hydroxide (Al (OH) ₃ ), and alumina sol.

  The particle size of the siliceous solid, the alkaline earth metal-containing compound, and the aluminum-containing compound may be any value that represents the size of each particle, and the siliceous solid has an average primary particle size, an aluminum-containing compound, and The alkaline earth metal-containing compound has a particle size in the kneaded product. These particle sizes can be measured by, for example, SEM images. These particle sizes can be adjusted by mixing classified products or by pulverization with a pulverizer such as a ball mill.

  The composition of the mixture can be determined according to the desired performance of the catalyst. For example, the content of the alkaline earth metal-containing compound in the mixture is 100 masses of siliceous solid from the viewpoint of suppressing the precipitation of carbon, which is a factor of catalyst deterioration, and preventing the decrease in the catalytic activity due to excessive addition. The amount is preferably 0.1 to 10 parts by mass, more preferably 0.5 to 8 parts by mass, and still more preferably 1 to 5 parts by mass with respect to parts.

In the mixture containing a siliceous solid containing the alkaline earth metal in the skeleton, the content of the alkaline earth metal in the siliceous solid is within the above range when the alkaline earth metal is converted as a carbonate. It is preferable from the above viewpoint. The mixture containing the siliceous solid containing the alkaline earth metal in the skeleton may further contain an alkaline earth metal compound from the above viewpoint, for example. The content of alkaline earth metal in siliceous solids containing alkaline earth metal in the skeleton may be obtained from catalog values, or obtained from measurements using elemental analyzers such as fluorescent X-ray analysis or ICP emission analysis. Also good.

  In addition, the content of the aluminum-containing compound in the mixture is determined from the viewpoint of improving the strength of the catalyst, the viewpoint of preventing a decrease in the catalyst performance due to the decrease in the concentration of the active ingredient zeolite, and the catalyst regeneration for removing the deposited carbon. From the viewpoint of suppressing the shortening of the operation interval, it is preferably 1 to 30 parts by mass, more preferably 5 to 20 parts by mass, and 8 to 15 parts by mass with respect to 100 parts by mass of the siliceous solid. More preferably.

  The mixture may further contain components other than the siliceous solid, the alkaline earth metal-containing compound, and the aluminum-containing compound described above. Examples of such other components include tungsten, phosphorus, boron, and compositions containing the same. Tungsten is considered useful for increasing the selectivity of lower hydrocarbons having 2 or 3 carbon atoms (see, for example, US Patent Application Publication No. 2008/0228020), and phosphorus and boron are catalyst catalysts. It is said that it has the effect of extending the life (see, for example, Ind. Eng. Chem. Res. 2009, 48, 6256-6261). These other components can be mix | blended with the said mixture in the range with which the effect of this invention is acquired.

  For example, the mixture is obtained by mixing a siliceous solid, if necessary, an alkaline earth metal-containing compound, an aluminum-containing compound, and, if necessary, other components using a normal apparatus used for mixing powders. Obtainable.

  The kneading step is a step of kneading the mixture and water in the presence of an anion that forms a water-soluble salt with the alkaline earth metal in the mixture and also forms a water-soluble salt with aluminum. is there. Here, water-soluble means a state in which 30 g or more is dissolved in 100 g of water at 20 ° C., and precipitation with time does not occur from the aqueous solution. Examples of such anions include nitrate ions and chlorine ions. The end point of the kneading process can be determined according to the particle size and dispersion state of the components in the kneaded product, such as siliceous solids, alkaline earth metal-containing compounds and aluminum-containing compounds in the kneaded product. Both the diameter and the dispersibility of the siliceous solid or alkaline earth metal-containing compound and the aluminum-containing compound can be determined as the point at which no change associated with kneading is observed. The particle size and dispersion state of the compound in the kneaded product can be confirmed by, for example, observing the dried and fired product of the collected kneaded product with an SEM.

  The kneading step can be performed by adding the anion to the mixture during the kneading step. Such a kneading step can be performed by kneading the mixture, water, and acid. The acid consists of the anion and hydrogen ion. Examples of such an acid include nitric acid and hydrochloric acid. The acid may be one kind or two or more kinds, but is preferably one kind from the viewpoint of safety. The acid may be added to the mixture, may be added to water before mixing with the mixture, or may be added to a mixture of the mixture and water.

  Or the kneading | mixing process can also be performed by producing the said anion from a mixture by kneading | mixing. Such a kneading step can be performed by blending a water-soluble salt composed of metal ions and the anions into the mixture. This water-soluble salt may be one kind or two or more kinds. The metal ions are preferably alkaline earth metal ions or aluminum ions from the viewpoint of suppressing changes in catalyst function due to diversification of the composition of cations in the mixture. Examples of the water-soluble salt include calcium nitrate, aluminum nitrate, calcium chloride, and aluminum chloride.

  In the kneading step, the content of the anion in the kneaded product is 10 per 100 parts by mass of siliceous solid in terms of acid with hydrogen ions from the viewpoint of improving the mechanical strength of the catalyst. It is preferably at least part by mass, more preferably at least 15 parts by mass, and even more preferably at least 20 parts by mass. In addition, the content of the anion is converted to an acid with hydrogen ions from the viewpoint of ensuring the effect on the apparatus and other materials during kneading and the catalytic function, and with respect to 100 parts by mass of siliceous solid. It is preferably 25 parts by mass or less, more preferably 10 parts by mass or less, and further preferably 5 parts by mass or less.

  In the kneading step, other components other than the mixture, water, and acid may be further added. Examples of such other components include spacer components that are removed by drying or baking after molding the kneaded product. Examples of such a spacer component include organic acids such as acetic acid and ammonia water removed by drying after molding, and graphite and celluloses and xanthan gum removed by baking. Xanthan gum is preferred from the viewpoint of the dispersibility of the zeolite. The content of the spacer component in the kneaded material is 0.5 to 10 parts by mass with respect to 100 parts by mass of the siliceous solid from the viewpoint of forming an appropriate porous structure in the catalyst and achieving sufficient catalyst strength. Is preferable, it is more preferable that it is 1-5 mass parts, and it is further more preferable that it is 1.5-2.5 mass parts.

  In the kneading step, from the viewpoint of workability at the time of kneading or molding (the hardness of the kneaded material), the water content of the kneaded material is preferably 10 to 50%, and preferably 20 to 40%. More preferably, it is more preferably 25-30%.

  Moreover, in the said kneading | mixing process, it is preferable that the temperature of a kneaded material is 10-50 degreeC from a viewpoint of suppressing evaporation of water, It is more preferable that it is 15-30 degreeC, It is 20-25 degreeC. Further preferred.

  The kneading step of adding the acid can be produced in the same manner as kneading in the production of a siliceous solid catalyst in which a kneaded product is molded and calcined except for the addition of such an acid. The kneading step of generating the anion from the mixture during kneading is performed in the production of a siliceous solid catalyst for forming and firing the kneaded material, except that the water-soluble salt is mixed with the mixture in advance. Can be produced in the same way as smelting.

  The kneaded product obtained in the kneading process is molded and fired to form a siliceous solid catalyst having a desired shape. The kneaded product can be molded in the same manner as a normal kneaded product in the production of a zeolite catalyst. Examples of such a molding technique include extrusion molding using an extruder and spherical body molding using a malmerizer, as described in Patent Document 2, for example.

  The molded product obtained by such molding is fired as it is, after drying, or pulverized as necessary. Calcination and drying of the molded product can be performed in the same manner as normal calcination and drying in the production of a zeolite catalyst. Firing can be performed at 350 to 750 ° C. for 1 to 50 hours, for example, as described in Patent Document 2, and drying is performed at 80 to 150 ° C. for 0.5 to 30 hours. be able to.

The method for producing a siliceous solid catalyst of the present invention may further include other steps than the above-described steps. As such other processes, for example, a part or all of siliceous solids, alkaline earth metal-containing compounds, aluminum-containing compounds, and water-soluble salts are pulverized with a normal powder pulverizer such as a ball mill. Powder grinding process to be used, siliceous solid, if necessary alkaline earth metal-containing compound, aluminum-containing compound, further water-soluble salt if necessary, for ordinary powder such as mixer The mixing process which mixes using a mixing apparatus and obtains a mixture, and the grinding | pulverization process which grind | pulverizes a molding or its dried product to the particle | grains of a desired magnitude | size are mentioned. These other steps can also be carried out according to the usual production of zeolite catalysts.

  The particle size of the siliceous solid catalyst can be determined according to the application of the catalyst. For example, in the case of the above-mentioned reaction catalyst for producing lower hydrocarbons, it is possible to suppress the enlargement of the reactor due to the increase in porosity in the reactor, to increase the catalytic activity, and to have sufficient strength of the catalyst against thermal vibration. From the viewpoint of obtaining high pressure in the reactor, the siliceous solid catalyst preferably has a particle size of 0.1 to 4 mm, more preferably 0.5 to 3 mm. More preferably, it is -2.5 mm. The particle size means the maximum diameter of a circle when the cross-sectional shape includes a circle, and the maximum length when the cross-sectional shape does not include a circle.

  In the case where the siliceous solid catalyst is cylindrical, the length of the siliceous solid catalyst (the length of the axis of the cylinder) is 0.5 to 10 mm from the same viewpoint as the particle diameter of the catalyst. Is preferably 1 to 8 mm, and more preferably 3 to 5 mm.

  The siliceous solid catalyst mainly has macropores distributed over the entire catalyst particles and communicating with each other, and mesopores opened on the wall surfaces of the macropores. For example, the macropores of the siliceous solid catalyst have the effect of promoting the diffusion of the reaction gas and increasing the effective active sites, thereby improving the productivity. Further, the mesopores have an effect of trapping coke deposited by the reaction and not covering the active sites, and the larger mesopore volume is better for the catalyst life. On the other hand, when the volume of the macropores and mesopores is too large, the porosity of the catalyst is increased and the strength of the catalyst may be decreased. The pore diameters of the macropores and mesopores can be appropriately determined from the range in which the effects of the present invention can be obtained based on the above viewpoint, since voids continuous with the catalyst particles are formed.

  The macropore diameter and mesopore diameter of the siliceous solid catalyst can be measured by a pore distribution measurement method using argon adsorption, nitrogen adsorption or mercury intrusion. Moreover, the macropore diameter of the siliceous solid catalyst can be adjusted by the type of the spacer component. The mesopore diameter of the siliceous fixed catalyst can be adjusted by the type of spacer component, the particle size of the zeolite, the type and particle size of the aluminum-containing compound, and the addition of acid.

The strength of the siliceous solid catalyst is such that the crushing strength per particle is 3 kgf (2.94 ×) from the viewpoint of suppressing pulverization and destruction of the catalyst particles at the time of filling and from the viewpoint of suppressing destruction of the catalyst particles due to thermal vibration. 10 ⁵ Pa) or more, preferably 4 kgf or more, and more preferably 7 kgf or more. The strength of the siliceous solid catalyst can be increased by increasing the amount of the acid or the water-soluble salt added, or by increasing the particle size of the siliceous solid catalyst.

  The siliceous solid catalyst obtained in the present invention can be used in a method for producing lower hydrocarbons by synthesizing lower hydrocarbons using one or both of dimethyl ether and methanol as raw materials. Such production methods include, for example, the aforementioned DTO reaction, MTO reaction, MTG reaction, fluid catalytic cracking, reaction to structurally isomerize a linear olefin into its corresponding methyl branched isoolefin, and 4 carbon atoms. Examples include a process for producing propylene from a raw material mixture containing the above olefin and methanol and / or dimethyl ether. The lower hydrocarbon refers to an olefin having 2 to 6 carbon atoms. For example, the siliceous solid catalyst obtained by the present invention can be used for producing ethylene and propylene using butene and dimethyl ether and / or methanol as raw materials, and propylene can be mainly produced in such a reaction. Such a lower hydrocarbon can be produced in the same manner as the method for producing a lower hydrocarbon described in Patent Document 2, for example, except that the siliceous solid catalyst obtained in the present invention is used.

In the present invention, the strength of the catalyst used for producing the lower hydrocarbon can be improved, the catalyst can be produced efficiently, and the obtained hydrocarbon can be used to produce the lower hydrocarbon. .

  The present invention can provide a siliceous solid catalyst having higher strength than before without increasing the amount of an aluminum-containing compound that functions as a binder. Therefore, it is possible to provide a siliceous solid catalyst having a desired strength and a smaller particle diameter, and a siliceous solid catalyst having a desired strength and a low content of an aluminum-containing compound. Improvement in catalytic activity per unit volume is expected, and further improvement in productivity in the production of lower hydrocarbons is expected.

  Further, in the present invention, when the water-soluble salt is used, damage to other materials in the mixture such as siliceous solids and corrosion of the kneading apparatus are suppressed as compared with the case where the acid is used in the kneading process. can do.

[Preparation of siliceous solid catalyst]
The method for preparing the siliceous solid catalyst of the present invention will be described more specifically.

[Example 1]
6.6 parts by mass of calcium carbonate (CaCO ₃ , Wako Pure Chemical Industries, JIS special grade) and 26 parts by mass of binder equivalent to Al ₂ O ₃ (boehmite (AlO (OH), JGC Catalysts and Chemicals) (Made by Co., Ltd.) was pulverized with a ball mill for 1 day (powder pulverization step) Next, 100 parts by mass of NH ₄ —ZSM-5 (Zeolist International, SiO ₂ / Al ₂ O ₃ mol) was added to this powder. Ratio = 716) and mixed for 5 minutes with a mixer (mixing step) This mixture, 54 parts by mass of ion-exchange water, and 2.4 parts by mass of nitric acid (HNO ₃ ) aqueous solution (concentration: 60 to 61 parts by mass) ) Was kneaded for 1 hour, 1.9 parts by mass of methylcellulose was further added and kneaded for 1 hour to prepare a kneaded product having a temperature of 10 to 50 ° C. and a moisture content of 27% by weight ( Kneading process).

  Next, the obtained kneaded product was molded into a catalyst diameter of 1.5, 2.0, and 3.0 mmφ by extrusion molding using an extruder to obtain a molded body (molding step). Next, the molded body obtained in the molding process was dried at 120 ° C. for 12 hours by a dryer (drying process). The dried molded body was pulverized so as to have a length of 3 to 8 mm (pulverization step). The pulverized cylindrical shaped body was fired at 600 ° C. for 8 hours in a muffle furnace (firing step). As a result, catalyst A was obtained.

[Example 2]
In the kneading step, powder pulverization, mixing, kneading, molding, drying, pulverization, and calcination were performed in the same manner as in Example 1 except that the amount of nitric acid aqueous solution added was 4.7 parts by mass. B was obtained.

[Example 3]
In the kneading step, powder pulverization, mixing, kneading, molding, drying, pulverization, and calcination were performed in the same manner as in Example 1 except that the amount of nitric acid aqueous solution added was 9.3 parts by mass. C was obtained.

[Example 4]
In the kneading step, powder pulverization, mixing, kneading, molding, drying, pulverization, and calcination were performed in the same manner as in Example 1 except that the addition amount of the nitric acid aqueous solution was 17.6 parts by mass. D was obtained.

[Example 5]
In the powder grinding step, 14.8 parts by mass of calcium nitrate (C
Each of powder pulverization, mixing, kneading, molding, drying, pulverization, and firing is the same as in Example 1 except that a (NO ₃ ) ₂ · 4H ₂ O) is used and no nitric acid aqueous solution is added in the kneading step. The process was performed and the catalyst E was obtained.

[Example 6]
In the powder pulverization step, the boehmite content is 21.6 parts by mass in terms of Al ₂ O _{3. In} the kneading step, 37.6 parts by mass of aluminum nitrate (Al (HNO ₃ ) Except for the addition of ₃ ) · 9H ₂ O, powder F, mixing, kneading, molding, drying, crushing, and firing were performed in the same manner as in Example 1 to obtain Catalyst F.

[Example 7]
In the kneading step, powder pulverization, mixing, and kneading were performed in the same manner as in Example 1 except that 4.7 parts by mass of hydrochloric acid (HCl) aqueous solution (concentration: 35 to 37% by weight) was added instead of nitric acid aqueous solution. Then, the respective steps of molding, drying, pulverization, and calcination were performed to obtain catalyst G.

[Example 8]
Example 1 except that the boehmite content was 11 parts by mass in terms of Al ₂ O ₃ in the powder pulverization step and the nitric acid aqueous solution was added at 7.9 parts by mass in the kneading step. In the same manner as above, powder pulverization, mixing, kneading, molding, drying, pulverization, and calcination were performed to obtain catalyst H.

[Example 9]
In the mixing step, the molar ratio of SiO ₂ / Al ₂ O ₃ is in place NH ₄ -ZSM-5 is 716, NH ₄ -ZSM-5 (Mitsubishi molar ratio of SiO ₂ / Al ₂ O ₃ is 900 (Made by Chemical Co., Ltd.) and powder grinding, mixing, kneading, molding, drying, grinding, and firing in the same manner as in Example 1 except that the amount of nitric acid aqueous solution added was 9.3 parts by mass in the kneading process. The process was performed and the catalyst I was obtained.

[Example 10]
In the powder pulverization step, calcium carbonate is not added, and in the mixing step, instead of NH ₄ -ZSM-5 (Mitsubishi Chemical Corporation), Ca-ZSM-5 (manufactured by JGC Corporation, SiO ₂ / Al ₂ O) is used. ₃ molar ratio = 195, CaO content = 1.22 wt%), and mixing, kneading, molding, as in Example 1, except that the amount of nitric acid aqueous solution added was 6.7 parts by mass in the kneading step. Each step of drying, pulverization, and calcination was performed to obtain catalyst J.

[Comparative Example 1]
In the kneading step, except for not adding the aqueous nitric acid solution, the steps of powder pulverization, mixing, kneading, molding, drying, pulverization, and calcination were performed in the same manner as in Example 1 to obtain catalyst K.

[Comparative Example 2]
In the powder pulverization step, the content of boehmite was 11 parts by mass in terms of Al ₂ O ₃ , and in the kneading step, powder pulverization was performed in the same manner as in Example 1 except that no nitric acid aqueous solution was added. Each step of mixing, kneading, molding, drying, pulverization, and calcination was performed to obtain catalyst L.

[Comparative Example 3]
In the powder grinding step, the molar ratio of SiO ₂ / Al ₂ O ₃ is in place NH ₄ -ZSM-5 is 716, NH ₄ -ZSM-5 molar ratio of SiO ₂ / Al ₂ O ₃ is 900 In the kneading step, except that the aqueous nitric acid solution was not added, the powder pulverization, mixing, kneading, molding, drying, pulverization, and firing steps were performed in the same manner as in Example 1 to obtain the catalyst M. It was.

[Comparative Example 4]
In the kneading step, catalyst N was obtained in the same manner as in Example 10 except that the nitric acid aqueous solution was not added, and powder pulverization, mixing, kneading, molding, drying, pulverization, and calcination were performed.

[Measurement of crushing strength]
The crushing strength of the catalyst A was measured by a Kiyama measurement method. That is, 20 particles having a particle diameter of 7 to 10 mm were randomly sampled from the catalyst A, and the cylindrical peripheral surface of each catalyst particle was measured with a pressure tip having a lifting speed of 1 mm / s and a pressure surface diameter of 5 mm. Was measured, and the value when the catalyst was crushed was measured, and the average value of the measured values was taken as the crushing strength. The unit is kgf / grain.

  The crushing strength of the catalysts B to N was measured in the same manner as the catalyst A. Table 1 shows the compositions of the catalysts and the measurement results of the crushing strength for the catalysts A to G and K. In Table 1, “*” indicates the measurement result when the catalyst diameter is 1.8 mmφ.

  As is clear from Table 1, the catalysts A to G have a high crushing strength with respect to the catalyst K, and the crushing strength of the catalysts A to G is larger as the particle size is larger than that of the catalyst K. The rate of increase is large.

  Table 2 shows the compositions of Catalyst H and Catalyst L and the measurement results of the crushing strength.

  From Table 2, the improvement of the crushing strength by addition of nitric acid was confirmed even with the catalyst prepared with a smaller binder amount than the catalyst K. Further, as is apparent from Table 2, a catalyst having a crushing strength equivalent to that of the catalyst K can be prepared with a binder amount smaller than that of the catalyst K by adding an aqueous nitric acid solution during kneading.

  Table 3 shows the compositions of Catalyst I and Catalyst M and the measurement results of the crushing strength.

From Table 3, it was confirmed that the crushing strength was improved by adding nitric acid even when zeolites having different SiO ₂ / Al ₂ O ₃ molar ratios were used. Further, as is apparent from Table 3, even when zeolite having a higher SiO ₂ / Al ₂ O ₃ molar ratio is used due to the addition of an aqueous nitric acid solution during kneading, the SiO ₂ / Al ₂ O ₃ molar ratio is higher. A crushing strength equal to or higher than that of a catalyst using a low zeolite can be obtained.

  Table 4 shows the compositions of the catalyst J and the catalyst N and the measurement results of the crushing strength.

  From Table 4, the improvement of the crushing strength by adding nitric acid was also confirmed when Ca-ZSM-5, which is a zeolite containing Ca in the framework, was used.

[Example 11]
[Propylene production]
The results of the production of propylene using the catalysts D and K as catalysts as examples are shown below. For the reaction, a fixed bed flow reactor was used, and 0.94 g of the catalyst was packed in an alumina reaction tube having an inner diameter of 6 mm. The reactor was fed with 13.7 mole% 1-butene, 19.6 mole% dimethyl ether, 47.0 mole% nitrogen, and 19.7 mole% water through an evaporator. The reaction conditions are shown below. Three hours after the start of the reaction, the product was analyzed by gas chromatography. Table 5 shows the reaction results. The WHSV (weight based space velocity) is the flow rate of the reaction raw material per weight of the catalyst (catalytic active component (NH ₄ —ZSM-5 in this embodiment)) after the granulation of the catalyst.
(Reaction conditions)
Reaction temperature: 525 ° C
Reaction pressure: 0.21 MPa
Catalyst particle size: 0.6 to 1.0 mm
WHSV (weight based space velocity): 4.5 to 18 h ⁻¹

Propylene was obtained with high selectivity for both catalysts D and K.
From the above, the catalyst obtained in the present invention has an equivalent excellent catalytic function as compared with the conventional catalyst, and the rate of increase in the strength of the catalyst is larger as the catalyst diameter is larger especially in the same catalyst diameter. It became clear that it was expensive.

  Lower olefins such as propylene are important as raw materials for chemical products, and the demand is expected to grow in the future. The present invention makes it possible to increase the mechanical strength of siliceous solid catalysts useful for the production of lower olefins without substantially changing the composition of metal ions in the catalyst. Is expected to do.

Claims (13)

A siliceous material comprising a kneading step of kneading a mixture containing siliceous solid, alkaline earth metal, and aluminum-containing compound with water, and molding the resulting kneaded material and calcining it to obtain a siliceous solid catalyst In the method for producing a solid catalyst,
In the kneading step, the mixture and water are kneaded in the presence of an anion that forms a water-soluble salt with an alkaline earth metal and also forms a water-soluble salt with aluminum. Of manufacturing a solid catalyst.   The said siliceous solid contains a silica, The manufacturing method of the siliceous solid catalyst of Claim 1 characterized by the above-mentioned.   The method for producing a siliceous solid catalyst according to claim 1 or 2, wherein the siliceous solid is zeolite.   The method for producing a siliceous solid catalyst according to any one of claims 1 to 3, wherein an alkaline earth metal is contained in the skeleton of the siliceous solid.   The said mixture is a mixture containing siliceous solid, an alkaline-earth metal containing compound, and an aluminum containing compound, The manufacturing method of the siliceous solid catalyst as described in any one of Claims 1-4 characterized by the above-mentioned. .   The method for producing a siliceous solid catalyst according to claim 5, wherein the alkaline earth metal-containing compound is a calcium-containing compound. The kneading step is a step of kneading the mixture, water and acid,
The said acid consists of the said anion and hydrogen ion, The manufacturing method of the siliceous solid catalyst as described in any one of Claims 1-6 characterized by the above-mentioned.   The method for producing a siliceous solid catalyst according to claim 7, wherein the acid is one or both of nitric acid and hydrochloric acid.   The method for producing a siliceous solid catalyst according to any one of claims 1 to 6, wherein a water-soluble salt composed of a metal ion and the anion is blended with the mixture.   The method for producing a siliceous solid catalyst according to claim 9, wherein the metal ions are alkaline earth metal ions or aluminum ions.   The method for producing a siliceous solid catalyst according to any one of claims 1 to 10, wherein in the kneading step, the water content of the kneaded product is 25 to 30%.   The method for producing a siliceous solid catalyst according to any one of claims 1 to 11, wherein in the kneading step, the temperature of the kneaded product is 10 to 50 ° C.   The manufacturing method of the lower hydrocarbon which synthesize | combines a lower hydrocarbon using one or both of dimethyl ether and methanol as a raw material using the siliceous solid catalyst obtained by the method as described in any one of Claims 1-12.