JP2992972B2 - Method for producing solid acid catalyst - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a process for producing a solid acid catalyst having an acid strength higher than 100% sulfuric acid (acid strength H ₀ = -11.93).

[0002]

2. Description of the Related Art In the chemical industry, alkylation reactions,
Many reactions requiring an acid catalyst, such as an esterification reaction and an isomerization reaction, have been performed. Conventionally, acid catalysts such as sulfuric acid, aluminum chloride, hydrogen fluoride, phosphoric acid, and paratoluenesulfonic acid have been used in this type of reaction. But,
These acid catalysts have the property of corroding metals, so that it is necessary to use expensive anticorrosion materials or to perform anticorrosion treatment.
In addition, usually, it is difficult to separate the reactants from the reactants after the reaction, and furthermore, waste acid treatment is required, and a complicated process such as alkali washing has to be performed. Furthermore, it was very difficult to reuse the catalyst.

In view of this situation, the present inventors have made contact with a sulfate group-containing solution of a Group IV metal hydroxide or hydrated oxide, and then calcined at 350 to 800 ° C. The inventors have found that the oxide has an acid strength higher than that of 100% sulfuric acid (H ₀ is −11.93), and proposed a method for producing a solid acid catalyst (Japanese Patent Publication No. 59-6181). Due to its high acid strength, this solid acid catalyst has high catalytic performance for various acid catalyzed reactions, has low corrosiveness, is easily separated from reactants, does not require waste acid treatment, and can be reused. It has the advantage of being possible, and is expected to replace conventional acid catalysts in various industrial reactions. However, since these solid acid catalysts are brought into contact with a sulfate group-containing compound in an aqueous solution, complicated steps such as filtration and drying are required, and there are problems such as an industrially high production cost. Further, as the sulfate group-containing compound, those using an aqueous solution of ammonium sulfate were known to have lower activity than those using sulfuric acid (catalyst, Vol. 21, No. 4, p217-2).
19 (1979)].

[0004]

SUMMARY OF THE INVENTION In view of the above situation, the present inventors have conducted intensive studies and as a result, have found that instead of contacting with a sulfate group-containing solution, ammonium sulfate is used as a solid without adding water. When mixed with a Group III or Group IV metal hydroxide or hydrated oxide, it has an activity equivalent to or higher than that of sulfuric acid, and can easily prepare a solid acid catalyst. In the preparation, it has been found that the activity can be greatly improved by including a Group VII metal or a Group VIII metal.

The present invention has been made based on such findings, and an object of the present invention is to provide a method for easily producing a highly active solid acid catalyst at low cost.

[0006]

According to one aspect of the present invention, there is provided a method for producing a solid acid catalyst comprising the step of preparing a hydroxide or hydrated oxide of a Group III or Group IV metal of the periodic table and ammonium sulfate in a solid state. After mixing, firing is performed in a temperature range of 350 to 900 ° C.

The above Group III or Group IV metals include
Aluminum, silicon, tin, lead, titanium, zirconium, hafnium and the like, in the present invention, in particular,
Aluminum, silicon, tin, titanium, zirconium, and hafnium are preferably used. These metals may be used alone or in combination of two or more.

The Group III or Group IV metal hydroxide or hydrated oxide is generally added to water or a mixed solution of water and an organic solvent in the above Group III or Group IV metal salt, for example,
Alcoholates, chlorides, sulfates, oxychlorides or oxysulfates of these metals are dissolved or suspended, and alkali, such as hydroxides or carbonates, such as sodium, potassium, and ammonium, are particularly preferable. Can be obtained by adding and neutralizing an aqueous ammonia solution. At this time, the final pH after neutralization is not particularly limited, but is preferably in the range of 6.5 to 8.5.
Further, the temperature of the solution may be room temperature, but preferably 4
When the temperature is raised to 0 ° C to 100 ° C, the activity of the finally produced solid acid catalyst is further improved.

[0009] The present invention relates to a method for producing a tertiary compound obtained by the above method.
A solid acid catalyst is prepared by mixing a hydroxide or hydrated oxide of a Group IV metal or a Group IV metal with ammonium sulfate in the solid state without forming an aqueous solution or the like. If the solid phase is maintained, there is no problem even if some water is contained. In this case, it is preferable to mix ammonium sulfate so that the amount of sulfur is 0.5 to 10 parts by weight based on 100 parts by weight of the finally obtained solid acid catalyst.

After the hydroxide or hydrated oxide of a Group III or Group IV metal and ammonium sulfate are mixed in this way, an activation treatment is further performed. The activation treatment is performed at 350 ° C. to 90 ° C. in a gas atmosphere such as air or nitrogen.
At a temperature of 0 ° C., particularly preferably between 350 ° C. and 750 ° C.
It is desirable to bake for 1 to 10 hours.

Another method for producing a solid acid catalyst according to the present invention is a method of mixing a group III or group IV metal hydroxide or hydrated oxide with ammonium sulfate in a solid state.
Containing a Group VII metal or a Group VIII metal,
Calcined in a temperature range of 00 ° C., or mixed in a solid state with a Group III or Group IV metal hydroxide or hydrated oxide, ammonium sulfate and a Group VII or Group VIII metal, The firing is performed in a temperature range of up to 900 ° C.

The mixing of the hydroxide or hydrated oxide of a Group III or Group IV metal with ammonium sulfate can be carried out in the same amount as described above in the same manner. The present invention relates to the mixture obtained in this way after containing a Group VII metal or a Group VIII metal,
Alternatively, these three types are mixed at the same time in the solid state and then calcined. In this case, as the Group VII or Group VIII metal, platinum, iridium, rhodium,
Platinum group elements such as ruthenium, osmium and palladium, or iron and manganese are preferably used. VI of these
The Group I or Group VIII metal is preferably used in the form of a compound rather than the metal itself. In particular, the use of an ammonium salt or a halide is preferred because of its high activity. As the halide, any of chloride, fluoride, bromide, and iodide may be used, but chloride is particularly preferable because it exhibits high activity. These metal compounds can be used both as anhydrides and hydrates. Further, these metal compounds may be one kind or a mixture of several kinds.

As a method for incorporating these metals into a hydroxide or hydrated oxide of a Group III or Group IV metal, when the metal compound is water-soluble, a usual impregnation method or the like is simple. However, it is convenient and preferable to mix a solid, preferably a powder of a metal compound, with a hydroxide or hydrated oxide of a Group III or Group IV metal in a solid state.

When the above three compounds are mixed simultaneously, the compound of the Group VII or VIII metal is used in the form of a powder, and the three compounds are simply mixed as they are.

The Group VII or VIII metal compound is added to 100 parts by weight of the finally obtained solid acid catalyst.
It is preferred that the metal be contained in an amount of 0.1 to 30 parts by weight as a Group VII or Group VIII metal.

The group III or group I thus obtained
A hydroxide or hydrated oxide of a Group V metal is mixed with ammonium sulfate, and a mixture containing a Group VII metal or a Group VIII metal is fired to perform an activation treatment. This activation process can be performed in the same manner as described above.

Further, another method for producing the solid acid catalyst according to the present invention relates to a method for preparing a solid acid catalyst comprising a Group VII metal or a Group VIII metal.
A group II or group IV metal hydroxide or hydrated oxide and ammonium sulfate are mixed in the solid state,
It consists of firing in a temperature range of ° C.

The present invention relates to a hydroxide or hydrated oxide of a Group III or Group IV metal,
After containing a Group VII metal or a Group VIII metal, ammonium sulfate is mixed and calcined in the same manner as described above to prepare a solid acid catalyst. Group III or IV in this case
The hydroxide or hydrated oxide of a group metal is also prepared by a method similar to the method described above. Further, for the Group VII or Group VIII metal used in the present invention,
The same as described above can be used,
The same applies to the content.

Thus, the hydroxide or hydrated oxide of a Group III or Group IV metal containing a Group VII metal or a Group VIII metal in advance can be obtained by the same method as described above. It is mixed with ammonium sulfate in the solid state using a similar amount. Then, activation processing is performed in the same manner as described above.

The solid acid catalyst obtained in the present invention has an acid strength higher than that of concentrated sulfuric acid (H ₀ ) -11.93, and exhibits excellent catalytic performance in various acid catalyzed reactions. Examples of applicable reactions include alkylation, esterification, isomerization, acylation, acetalization, and polymerization. When the solid acid catalyst obtained in the present invention is used in these reactions, the reaction proceeds in a heterogeneous system, and after the reaction, the catalyst and the reactants can be easily separated by means such as filtration, and the waste acid There is no need for treatment, and the catalyst can be reused. The acid strength (H ₀ ) of the solid acid catalyst can be directly measured using an acid-base conversion indicator having a known pKa value. For example, p-nitrotoluene (pKa value; -11.4), m-nitrotoluene (pKa value;
-12.0), p-nitrochlorobenzene (pKa value; -12.
7) 2,4-dinitrotoluene (pKa value: -13.8), 2,
4-dinitrofluorobenzene (pKa value: -14.5), 1,
The catalyst is immersed in a solution of dry cyclohexane or sulfuryl chloride such as 3,5-trichlorobenzene (pKa value: -16.1), and the indicator is discolored to an acidic color by observing the discoloration of the indicator on the surface of the catalyst. It is equal to or less than the pKa value. However, catalysts containing Group VII or VIII metals are colored and cannot be measured with indicators. It has been reported that this type of catalyst can be estimated from the isomerization activity of butane and pentane ["Studies in Surf"
ace Science and Catalysis "Vol.90, ACID-BASE CATAL
YSIS II, p.507 (1994)]. Therefore, in the present invention, the isomerization activity of butane was measured, and the measurement was replaced with the measurement of the acid strength.

[0021]

EXAMPLES Preparation Example of Catalyst (Catalyst 1) 50 g of commercially available zirconium oxychloride was dissolved in 1 liter of distilled water, and 28 wt% aqueous ammonia was added with stirring until a final pH of 8 was reached to form a precipitate. Squeezed. The resulting hydrated zirconia was filtered, washed with distilled water, and dried at 50 ° C. for 48 hours to obtain dried hydrated zirconia 2
2 g were obtained. Then, 3.6 g of ammonium sulfate was added, and the mixture was pulverized by a pulverizer. The resulting mixture is placed in an air stream at 60
The mixture was calcined at 0 ° C. for 3 hours to obtain about 20 g of a sulfate group-containing zirconia catalyst.

(Catalyst 2; Comparative catalyst) 2 g of dry hydrated zirconia obtained in the same manner as in Preparation Example of Catalyst 1 was immersed in 30 ml of 1 N sulfuric acid for 1 hour. After removing excess sulfuric acid by filtration, the mixture was dried at room temperature for 48 hours. The dried sulfuric acid-treated product was calcined at 600 ° C. for 3 hours in an air stream to obtain about 1.8 g of a sulfate group-containing zirconia catalyst.

(Catalyst 3, 4) 50 g of commercially available zirconium oxychloride was dissolved in 1 liter of distilled water, and 28%
Aqueous ammonia was added until a final pH of 8 resulted in precipitation. The formed hydrated zirconia was filtered, washed with distilled water, and dried at 100 ° C. for 24 hours to obtain 20 g of dried hydrated zirconia. The dried hydrated zirconia was impregnated with a 3% by weight aqueous solution of iron chloride (FeCl ₃ ) so that the iron content was 2.1% by weight with respect to the dried hydrated zirconia. After drying at 100 ° C. for 24 hours, ammonium sulfate was further added to dry hydrated zirconia so that the sulfur content was 4% by weight, and the mixture was pulverized and mixed in a solid phase. This mixture was calcined in an air stream at 700 ° C. for 3 hours to obtain an iron-containing sulfated zirconia catalyst (catalyst 3). Instead of iron chloride, manganese chloride (MnCl ₂ .4H ₂ O) was added to dry hydrated zirconia so that the amount of manganese was 2.1% by weight, and calcined at 725 ° C. for 3 hours in an air stream to obtain manganese. A sulfated zirconia-containing catalyst (catalyst 4) was obtained.

(Catalyst 5; Comparative catalyst) A 10% by weight aqueous solution of iron nitrate (Fe (NO ₃ ) ₃ ) and 10% by weight were added to dry hydrated zirconia obtained in the same manner as in Preparation Examples of Catalysts 3 and 4. Manganese nitrate (Mn (NO ₃ ) ₂ ) aqueous solution is impregnated with dry hydrated zirconia so that the iron content is 1.5% by weight and the Mn content is 0.5% by weight. Was impregnated so that the sulfur content was 4% by weight with respect to the dry hydrated zirconia. After the product was dried at 100 ° C. for 24 hours, it was calcined at 725 ° C. for 1 hour in an air stream to obtain an iron-manganese-containing sulfated zirconia catalyst (catalyst 5).

(Catalyst 6-9) 100 g of commercially available zirconium oxychloride was dissolved in 2 liters of distilled water, and the solution was stirred at room temperature while 28% aqueous ammonia was added thereto.
Until a precipitate formed. The resulting hydrated zirconia was filtered, washed with distilled water, and dried at 100 ° C. for 24 hours. Platinum (II) chloride is added to the dried hydrated zirconia so that the platinum amount becomes 7.5% by weight based on the dried hydrated zirconia, and ammonium sulfate is further added to the dried hydrated zirconia so that the sulfur amount becomes 4% by weight. And these were ground and mixed in the solid phase. This mixture is placed in an air stream at 60
The mixture was calcined at 0 ° C. for 3 hours to obtain a platinum-containing sulfated zirconia catalyst (catalyst 6). The amount of platinum in this catalyst was 7.6% by weight. Also, instead of platinum (II) chloride, iridium (III) chloride (catalyst 7), rhodium (III) chloride (catalyst 8), ruthenium (III) chloride (catalyst 9) were used. 7.4% by weight, 4.0% by weight, respectively
In addition, a platinum group element-containing sulfate zirconia catalyst was prepared in addition to 3.9% by weight.

Activity Test The catalysts prepared above were compared for catalytic activity by measuring the conversion and selectivity of skeletal isomerization of butane.

The catalytic activity was measured using a fixed bed pulse reactor (H
e Carrier gas flow rate: 20 ml / min, catalyst amount: 0.1 g,
Using a pulse size of 0.05 ml), the reaction gas was directly subjected to gas chromatography (column: VZ-7, 6 m, 30 ° C.).
And analyzed the generated gas. Before the start of the reaction, the catalyst was subjected to a heat treatment at 300 ° C. for 1 hour in a flowing He atmosphere before use. The results of the reactions for the catalysts 1 to 5 are shown in FIG. 1, and the results of the reactions for the catalyst 2 and the catalysts 6 to 9 are shown in FIG.

From these results, it can be seen that the sulfate-containing zirconia catalyst prepared by the method of the present invention has a sulfate-containing zirconia catalyst using sulfuric acid which cannot be expected from the use of an aqueous ammonium sulfate solution in the skeletal isomerization reaction activity of butane. The activity is almost the same as zirconia catalyst, and the production process is very simple because the sulfuric acid separation step and the treatment of separated waste sulfuric acid are not required compared with the case of using sulfuric acid. It can be seen that they can be manufactured at low cost.

Further, it can be seen that any of the catalysts containing Group VII or VIII of the present invention significantly improves the activity of the skeletal isomerization reaction of butane. Since the acid strength (H ₀ ) of the zirconia sulfate catalyst used this time was -16.12 or less, the acid strength (H ₀ ) of the catalyst of the present invention calculated from the skeletal isomerization reaction of n-butane was At least -1
It turned out to be 6 or less.

[0030]

The present invention has a special effect that a solid acid catalyst having high acid strength and high activity can be easily produced at low cost. Since these solid acid catalysts have high acid strength, they exhibit high catalytic functions in various acid catalyzed reactions such as alkylation, esterification, and isomerization, are less corrosive, and can be easily separated from reactants. It has many advantages such as no need for waste acid treatment and the ability to reuse the catalyst.

[Brief description of the drawings]

FIG. 1 is a diagram showing the skeletal isomerization reaction activity of butane with respect to catalysts 1 to 5, wherein the vertical axis represents the conversion of butane (%) and the horizontal axis represents the isomerization temperature (° C.).

[Explanation of symbols]

Δ: catalyst 1, ○: catalyst 2, Δ: catalyst 3, ●: catalyst 4,
■: Catalyst 5

FIG. 2 is a diagram showing the skeletal isomerization activity of butane with respect to Catalyst 2 and Catalysts 6 to 9, wherein the vertical axis represents the conversion of butane (%);
The horizontal axis is the isomerization temperature (° C.).

[Explanation of symbols]

×: catalyst 2, ○: catalyst 6, Δ: catalyst 7, ●: catalyst 8,
■: Catalyst 9

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ identification code FI C07C 5/27 C07C 5/27 9/10 9/10 (58) Fields surveyed (Int.Cl. ⁶ , DB name) B01J 21 / 00-38/74 JICST file (JOIS) WPI (DIALOG)

Claims (4)

(57) [Claims] The present invention is characterized in that a hydroxide or hydrated oxide of a Group III or Group IV metal of the periodic table and ammonium sulfate are mixed in a solid state and then calcined in a temperature range of 350 to 900 ° C. For producing a solid acid catalyst. 2. Mixing a hydroxide or hydrated oxide of a Group III or Group IV metal of the periodic table with ammonium sulfate in a solid state, and then adding a Group VII metal or Group VIII metal to form a mixture. Calcination in a temperature range of ９００900 ° C., or mixing of a Group III or Group IV metal hydroxide or hydrated oxide with ammonium sulfate and a Group VII or Group VIII metal in a solid state, A method for producing a solid acid catalyst, comprising calcining in a temperature range of 350 to 900C. 3. Mixing a hydroxide of a Group III or Group IV metal or a hydrated oxide containing a Group VII metal or Group VIII metal of the periodic table with ammonium sulfate in a solid state, A method for producing a solid acid catalyst, comprising calcining in a temperature range of 900 ° C. 4. The periodic table No. VI according to claim 2 or 3.
A method for producing a solid acid catalyst, wherein the Group I metal or Group VIII metal is one or more metals selected from iron, manganese and platinum group elements.