JPH052378B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a method for producing a nickel-containing crystalline aluminosilicate, and more specifically to a crystalline aluminosilicate containing nickel and having a novel crystal structure in which at least a portion of the nickel is composed of bonds other than ionic bonds. The present invention relates to a method for producing silicates. (Prior Art) Crystalline aluminosilicate is generally useful as a catalyst for various chemical reactions, and various methods have been attempted for its modification. For example, JP-A-52-
No. 156798 discloses a method of improving thermal stability and water vapor stability by exchanging metal ions at pH 1.5 to 5.5. In addition, PH
A modification method is disclosed in which the iron salt is treated with an aqueous iron salt solution of 2.0 or less to give a unique structure and performance. (Means for solving the problem) The present inventors have a new structure and performance,
We conducted intensive research to develop crystalline aluminosilicate with extremely high catalytic activity. As a result, the PH2.0 described in the above-mentioned Japanese Patent Application Laid-Open No. 58-2214
By treating with a nickel salt aqueous solution with a pH of less than 1.5 instead of the following iron salt aqueous solution, the catalytic activity, especially the disproportionation reaction activity of aromatic compounds such as toluene, can be improved compared to iron-containing crystalline aluminosilicate. It has been found that a significantly improved nickel-containing crystalline aluminosilicate can be obtained. The present invention was completed based on this knowledge. That is, in the present invention, SiO ₂ /Al ₂ O ₃ is 4.6 (molar ratio)
Provided is a method for producing a nickel-containing crystalline aluminosilicate, which is as described above and is characterized in that the crystalline aluminosilicate having a Na ₂ O content of 2.4% by weight or less is brought into contact with an aqueous nickel salt solution having a pH of less than 1.5. It is. The crystalline aluminosilicate that is the raw material for the method of the present invention has a SiO ₂ /Al ₂ O ₃ molar ratio, that is, a ratio of silica to alumina (mole ratio) of 4.6 or more, and a Na ₂ O content of 2.4% by weight. % or less, preferably 1% by weight or less, and there are various types, such as natural zeolites such as houjasite, mordenite, X type, Y type,
Synthetic zeolites such as L-type can be mentioned. Any of these can be used, but those with a large effective cavity diameter are particularly preferred. In addition, if the crystalline aluminosilicate used as a raw material has a silica to alumina ratio of less than 4.6 or a Na ₂ O content of more than 2.4% by weight, it will be treated under strong acidity with a pH of less than 1.5. Moreover, the silicate skeleton may be destroyed, which is not preferable. Next, as the nickel salt aqueous solution used in the method of the present invention, various salts and complex salts can be used, but aqueous solutions of nickel chloride, nickel nitrate, nickel sulfate, etc. are generally used. In the method of the present invention, when the above-mentioned crystalline aluminosilicate is brought into contact with the nickel salt aqueous solution, it is necessary to adjust the pH of the system to less than 1.5. Therefore, depending on the type of nickel salt used, it may be necessary to add an acid, and as such an acid, hydrochloric acid, nitric acid, sulfuric acid, etc. may be used. However, hydrofluoric acid, which destroys the structure of crystalline aluminosilicate, is not preferred. When a crystalline aluminosilicate is brought into contact with a nickel salt aqueous solution whose pH has been adjusted to less than 1.5, the aluminum constituting the aluminosilicate crystals will be eluted, but if the nickel salt aqueous solution has a pH of 1.5 or higher, aluminum will not be absorbed sufficiently. The target crystalline aluminosilicate cannot be produced. In the method of the present invention, there are no particular restrictions on the conditions for contacting crystalline aluminosilicate with an aqueous nickel salt solution having a pH of less than 1.5, and the conditions may be determined as appropriate, but usually at a temperature of 0 to 100°C. ,0.5~10
Leave in contact for about an hour. The contacting method may be simply by immersing the crystalline aluminosilicate in the nickel salt aqueous solution, but the purpose can be achieved in a shorter time by stirring or the like. Further, such contact may be carried out only once, but if it is repeated multiple times, an aluminosilicate with a high nickel content can be obtained. Furthermore, it is effective to use ultrasonic waves for contacting. In addition, in the method of the present invention, it is also effective to subject the crystalline aluminosilicate as a raw material to steam treatment before contacting it with an aqueous nickel salt solution. In this case, the treatment is preferably carried out in the presence of water vapor at a temperature of 540 to 810°C. Here, the steam treatment may be performed in a flow system, or the crystalline aluminosilicate may be held in a closed container and heated, and self-steaming may be performed using the water contained in the aluminosilicate. After contact-treating crystalline aluminosilicate with a nickel salt aqueous solution according to the method of the present invention, the obtained aluminosilicate is thoroughly washed according to a conventional method, and if necessary, dried and then calcined (300
~800℃), the desired nickel-containing crystalline aluminosilicate can be produced. The crystalline aluminosilicate obtained in this way contains nickel inside, but at least a part of the nickel is bonded to the aluminosilicate in a form other than an ionic bond, which is different from conventional nickel. It is significantly different from the aluminosilicate contained therein in its crystal structure, catalytic action, etc. The crystalline aluminosilicate produced by the method of the present invention contains nickel in the form described above, but other compositions, crystal structures, etc. may differ slightly depending on various conditions during production. However, it is not constant. However, a preferable one is the compositional formula pNa ₂ O.qAl ₂ O _{3.rNiO.SiO 2} [wherein p≦0.032, q<1/4.6, 0<r≦10. ] and has an X-ray diffraction pattern as shown in Table 1.

【table】

[Table] (Effects of the invention) Since the nickel-containing crystalline aluminosilicate produced by the method of the present invention has the above structure and composition, it can be used as a catalyst as it is, and can also be used as a catalyst. It can also be used as a carrier. For example, when toluene is passed through the above-mentioned crystalline aluminosilicate as a catalyst, a disproportionation reaction occurs, and it exhibits a characteristic that precipitation of carbon on the catalyst accompanying the reaction is extremely small. In particular, this nickel-containing crystalline aluminosilicate exhibits high catalytic activity even with a small amount of metal introduced compared to the iron-containing crystalline aluminosilicate described in JP-A No. 58-2214. It has the advantage of high reaction rate of disproportionation reaction. Note that this reaction is more effective if carried out under sulfurized conditions. In addition, this catalyst, in which nickel and tungsten are supported on a carrier prepared from crystalline aluminosilicate and alumina, has high activity in the hydrocracking of distillate oil, petroleum residue oil, etc. It has the advantage of less precipitation. As mentioned above, the crystalline aluminosilicate obtained by the method of the present invention can be used in various conversion reactions of organic compounds, such as catalytic cracking reactions, disproportionation reactions, alkylation reactions, isomerization reactions, hydration reactions, and dehydration reactions. ,
Polymerization reaction, demetalization reaction, desulfurization reaction, denitrification reaction,
It is useful as a catalyst or catalyst carrier for reforming reactions, etc., and the amount of carbon deposited during these reactions is extremely small, so it can maintain high activity over a long period of time. Moreover, this crystalline aluminosilicate has the advantage that it has higher thermal stability than conventional aluminosilicate, and its crystallinity does not deteriorate even in a high-temperature atmosphere. Incidentally, even if ordinary aluminosilicate is impregnated with nickel or tungsten, or even if the exchange rate of nickel ions is increased, the above-mentioned effect cannot be obtained. Furthermore, the crystalline aluminosilicate produced by the method of the present invention can be used not only as a catalyst or catalyst support.
It is also useful as an adsorbent and exhibits unique adsorption properties not found in conventional adsorbents. (Example) Next, the present invention will be explained in more detail with reference to Examples. Example 1 SiO ₂ /Al ₂ O ₃ = 5.2 (molar ratio), Na ₂ O 0.5wt%
Add 13.4 N nitric acid to 80 g of NH ₄ Y-type zeolite (crystalline aluminosilicate) and 800 ml of an aqueous nickel nitrate solution with a concentration of 1.0 mol/adjust the pH to 0.3. Pour the solution into a 1-volume three-necked flask.
Contact treatment was carried out by stirring at 100°C for 2 hours. Then filtered, washed with warm water and dried at 90 °C, followed by
A nickel-containing crystalline aluminosilicate was obtained by firing at 450°C. The operating conditions and the properties of the nickel-containing crystalline aluminosilicate (produced zeolite) are shown in Table 2, and the X-ray diffraction pattern of the produced zeolite is shown in Table 3. Comparative Example 1 The same operation as in Example 1 was carried out except that nitric acid was not added in Example 1 and 400 ml of nickel nitrate aqueous solution with a concentration of 0.035 mol/ was used and the contact treatment was performed at 20°C for 30 minutes. . Second result
Shown in Table and Table 3. Comparative Example 2 After compression molding the NH ₄ Y type zeolite used in Example 1, it was pulverized and the particle size was adjusted to 32 mesh to 65 mesh, and 12 g of the particles had a concentration of 0.62 mol/
6.8 ml of nickel nitrate aqueous solution was impregnated under vacuum.
Next, it was dried at 90°C and then calcined at 450°C to obtain a nickel-containing crystalline aluminosilicate. The results are shown in Tables 2 and 3. Comparative Example 3 80 g of the NH ₄ Y-type zeolite used in Example 1 and 800 ml of a nitric acid solution whose pH was adjusted to 0.7 with concentrated nitric acid were placed in a 1-volume three-necked flask, and the mixture was stirred at 50°C for 2 hours for contact treatment. . The product was then filtered, washed with warm water, and dried at 90°C to obtain dealuminated crystalline aluminosilicate. After compression molding this thing,
The particle size was adjusted to 32 mesh to 65 mesh by pulverization. Further, 11 g of this material was impregnated with 6.7 ml of an aqueous nickel nitrate solution having a concentration of 0.61 mol/min under vacuum.
Subsequently, it was dried at 90°C and calcined at 450°C to obtain a nickel-containing crystalline aluminosilicate. Second result
Shown in Table and Table 3. Comparative example 4 SiO ₂ /Al ₂ O ₃ = 5.3 (molar ratio), Na ₂ O 0.4wt%
NH ₄ Y-type zeolite 100g and concentration 0.25mol/
Pour 800 ml of ferric nitrate aqueous solution (PH 1.3) into a 1-volume three-necked flask, stir at 50°C for 2 hours,
After that, it was suction filtered, and after washing thoroughly with 50°C water, it was dried at 50°C for 4 hours, and then 500°C
C. for 3 hours to obtain iron-containing crystalline aluminosilicate. The results are shown in Tables 2 and 3. Comparative Example 5 The NH ₄ Y-type zeolite used in Example 1 was
It was baked at ℃ for 3 hours. The results are shown in Tables 2 and 3.
Shown in the table.

【table】

[Table] Application example 1 and reference examples 1 to 4 After molding the crystalline aluminosilicate obtained in the example or comparative example at a pressure of 600 kg/cm ² G, 32
The particle size was adjusted to ~65 mesh, and 5 ml of this was filled into a stainless steel reactor with an inner diameter of 6 mm as a catalyst.
In this reactor, toluene disproportionation reaction was carried out under pressure of hydrogen and hydrogen sulfide under the following conditions.
The results are shown in Table 4. Reaction temperature: 350℃, pressure: 60Kg/cm ² G, liquid hourly space velocity (LHSV): 4hr ^-1 , supply rate of hydrogen and hydrogen sulfide (0.2vol%): 210ml/min

[Table] Comparing Application Example 1 and Reference Example 4, Application Example 1 has a nickel content (NiO equivalent) of 3.2wt%, which is lower than the iron content (Fe ₂ O ₃ equivalent) of 8wt% in Reference Example 4. Despite the use of catalysts, the toluene conversion rates (ie catalytic activities) are approximately the same. Moreover, in Application Example 1, the disproportionation rate is high, and the hydrogenation rate and carbonaceous material production rate are low. This means that the disproportionation reaction, which is the main reaction, proceeds efficiently and side reactions such as hydrogenation reactions are suppressed.

Claims (1)

[Claims] 1 A crystalline aluminosilicate having a SiO ₂ /Al ₂ O ₃ ratio of 4.6 (molar ratio) or more and a Na ₂ O content of 2.4% by weight or less is brought into contact with an aqueous nickel salt solution having a pH of less than 1.5. A method for producing a nickel-containing crystalline aluminosilicate.