JPH01110636A - Production and catalyst of dialkylnaphthalene - Google Patents

Abstract

PURPOSE:To improve yield and selectivity of the aimed compound in producing the titled compound from a naphthalene and an olefin, by using a silica alumina catalyst containing a specific amount of fluorine and reacting under a specific condition. CONSTITUTION:A raw material containing a material for alkylation selected from naphthalene and monoalkylnaphthalene containing 1-4C alkyl group is brought into contact with an alkylating agent selected from 2-4C olefin in the molar ratio of the alkylating agent/the material to be alkylated of 0.1-10 in the presence of a silica alumina catalyst containing 0.1-15wt.% fluorine at 200-450 deg.C under 2-30kg/cm<2>G and 0.2-10Hr<-1> LHSV to give a dialkylnaphthalene, especially, 2,6-dialkylnaphthalene in high yield for a long period stably. The reaction product after separation of the aimed compound is circulated and used so that the yield of the aimed compound can be further raised.

Description

DETAILED DESCRIPTION OF THE INVENTION -1 The present invention relates to a method for obtaining dialkylnaphthalenes, particularly 2,6-dialkylnaphthalenes, from naphthalenes and olefins.

■Japanese Patent Publication No. 56-2532 describes a method in which naphthalene and propylene are reacted in the presence of a solid acid catalyst such as silica/alumina or zeolite, and then a dipropylnaphthalene fraction is collected by fractional distillation. However, these solid acid catalysts still have insufficient transalkylation activity, isomerization activity, and catalyst life. (See Comparative Example 1 and Comparative Example 8 described later) ■Japanese Patent Publication No. 42-3617 has a Hammett acidity function value smaller than -8.0 and contains 2 to 12% by weight of fluorine.
, preferably containing 2 to 8% by weight of alumina, silica, silica-alumina, silica-alumina-magnesia, silica-magnesia, silica-zirconia, alumina-zirconia, alumina-boria, zirconium dioxide and titanium dioxide. 45 refractory inorganic oxides
Refine alkylation of aromatic hydrocarbons at 1-200 atm and 210-325°C using a catalyst calcined in the presence of a substantially anhydrous, oxygen-free inert gas at 0-700°C. Method of carrying out the reaction, and 1 to 200 atmospheres, 220
A method is described for carrying out the transalkylation reaction of alkyl aromatic hydrocarbons at ~350°C. Examples include only monocyclic aromatic alkylation and transalkylation, but
Naphthalene and alkylnaphthalene are also listed as aromatics.

However, not all of the above-mentioned fluorine-containing inorganic oxides are suitable as catalysts in the production of dialkylnaphthalenes by alkylation of naphthalenes and/or monoalkylnaphthalenes. (See Comparative Example 5 and Comparative Example 7 described below) Furthermore, the optimum reaction conditions for producing dialkylnaphthalene are not disclosed.

The purpose of the present invention is to provide a method capable of stably obtaining dialkylnaphthalene, particularly 2,6-dialkylnaphthalene, in high yield and over a long period of time from naphthalenes and olefins. .

The method for producing dialkylnaphthalene according to the present invention has a method for producing dialkylnaphthalene.
In the presence of a silica-alumina catalyst containing 1-15% by weight of fluorine, reaction temperature 200-450°C, reaction pressure 2-
30Kg/cm2G and LHSV0.2~10Hr-'
Under the following conditions, a raw material containing an alkylated compound selected from the group consisting of naphthalenes, lunaphthalene, an alkylating agent selected from 02 to C4 olefins, and a molar ratio of alkylating agent/alkylated compound It is characterized by contacting at a ratio of 0.1 to 10.

The base silica/alumina may have an Aj2203 content of 10 to 80% by weight.

Commercially available silica-alumina catalysts can also be used. The fluorine content of the catalyst is between 0.1 and 15% by weight, preferably 0.
．． The content is 5 to 13% by weight. If it is less than 0.1% by weight, the effect of fluorination treatment is small, and if it is more than 15% by weight, Ag2O3
AgF2 is formed by the combination with silica and alumina, leading to structural destruction of silica and alumina (.

Fluorination treatment of silica/alumina catalysts uses fluorine-containing compounds such as ammonium fluoride, hydrogen fluoride, methylammonium fluoride, metal fluorides, and chlorofluorocarbon gas as a fluorination agent, and produces fluorine-containing compounds obtained as liquids or solutions. In this case, a normal impregnation method may be used.

Alternatively, a method may be used in which a solid fluorine-containing compound and silica/alumina are powdered and mechanically mixed and molded.

When the fluorine-containing compound is a gas, the gas heated to 300 to 600° C. is introduced into the catalyst layer to perform the fluorination treatment.

The raw material containing the alkylated substance is naphthalene or C1
- Monoalkylnaphthalene having an alkyl group of C4, alone or in a mixture thereof, or in addition to this, di-,
It may also contain trialkylnaphthalene.

For example, a mixture (a mixture of naphthalene, mono-, di-, tri-, tetra-alkylnaphthalene, etc.) after separating and removing the desired dialkylnaphthalene from the product obtained by reacting the product to be alkylated with an alkylating agent is prepared as described above. It may be used by circulating it in the reaction process.

The desired dialkylnaphthalene can be separated from the product by appropriately using methods such as distillation separation, crystallization separation, and adsorption separation.

The silica-alumina catalyst containing 0.1 to 15% by weight of fluorine used in the present invention has excellent ability not only for alkylation but also for transalkylation and isomerization. can be obtained in good yield.

As alkylating agent, 02 to C4 olefins are used, preferably propylene.

The molar ratio of alkylating agent/alkylated substance is 0°1 to 10
, preferably 0.3-5, more preferably 0.5-3
shall be.

The reaction temperature is 200-450°C, preferably 220-35°C.
The temperature shall be 0°C. If the temperature is too low, the transalkylation reaction becomes insufficient and the yield of dialkylnaphthalene, especially 2,6-dialkylnaphthalene, decreases. If the temperature is too high, dealkylation will progress as well as alkylation, making it easier for the polymerization reaction to occur.

The reaction pressure is 2 to 30 Kg/cm2G, preferably 3 to 1
It is preferable to set it to 5Kg/cm2G.

LHSV is 0.2-1OHr-', preferably 0.2-1OHr-'
It is preferable to set it as 5 Hr-'.

The structure and effects of the present invention will be specifically explained below using Examples and Comparative Examples.

[Example 1] Silica/alumina pulverized to 12 to 28 mesh (
Aρ203: 28% by weight)・l Occ contains 400% decalin containing 2000voβppm of 1-fluorohexane.
After flowing for 24 hours under the conditions of ℃, l OKg/cm2G, LHSVl, 0Hr-', it was heated to 530℃ under air circulation for 3 hours.
A silica-alumina catalyst having a fluorine content of 0.6% by weight was obtained by firing for a period of time.

The above fluorinated silica and
Filled with 6 cc of alumina catalyst, under the conditions of reaction temperature 280°C, pressure cuff, 0 Kg/cm2G%LHSV1.0Hr-', naphthalene and propylene in an amount twice the mole of the substance to be alkylated (naphthalene) were supplied. A chemical reaction was carried out.

[Comparative Example 1] For comparison, an alkylation reaction was carried out under the same conditions as in Example 1 using the silica-alumina catalyst used as a material in Example 1 and not subjected to fluorination treatment.

The reaction test results of Example 1 and Comparative Example 1 are shown in Table 1.

In Table 1, the fluorinated product containing 1:2,6-diitubropylnaphthalene has a higher yield of vegetable isobrobylnaphthalene than the untreated product, especially the yield of 2,6-diitubrobylnaphthalene. efficiency has improved and catalyst life has also been extended.

[Examples 2 to 100 and Comparative Example 2] 100 g of the same silica/alumina used in Example 1
After impregnating with 70cc of 10% HF aqueous solution.

It was dried at 120°C for a day and night, and then fired at 530°C in air for 3 hours. The composition of the catalyst ① prepared in this way is F
(4.3% by weight) SiO2.Aj2203.

In a similar manner, F (2.1% by weight) SiO2・Aj22
Catalyst ■ with the composition of 03, F (1.0% by weight) SiO
2. Catalyst (2) having the composition of Aj2203 was prepared.

In addition, the same silica-alumina 10 used in Example 1
After impregnating 0g with 80cc of distilled water in which 7g of NH4F was dissolved, it was dried at 120°C day and night, and then calcined at 530°C in air for 3 hours. The composition of the catalyst ① prepared in this way is F
(1.6% by weight) Si02 .Al2z Os.

In a similar manner, F (12.6% by weight) SiO2・Al2
Catalysts V1 and F with a composition of 203 (16% by weight) Si
Catalyst (2) having a composition of O2.Aρ20X was prepared. Catalyst Vl contains 16% by weight of fluorine and is therefore outside the scope of the present invention.

Fill the above catalysts ~ Vl into a small catalyst activity tester, and
A reaction test was conducted under the same reaction conditions as in Example 1 except that HSV or reaction temperature was changed. The results are shown in Table 2.

As is clear from Table 2, the fluorine content is 16% by weight.
In Comparative Example 2 using catalyst Vl, the yield of diisopropylnaphthalene, especially 2,6-diisopropylnaphthalene, was lower.

[Comparative Examples 3 to 7] In Comparative Examples 3 and 4, the same silica-alumina catalyst as used in Comparative Example 1 was used.

In Comparative Example 5, 85 g of a commercially available Al203 molded product was impregnated with aqueous ammonium fluoride (8.4 g of NH4F + 75 g of pure water), dried at 120°C for a day and night, and then
An alumina catalyst with a fluorine content of 2.3% by weight obtained by firing in air at 30° C. for 3 hours was used.

In Comparative Example 6, a silica-titania (Ti02: 90% by weight) catalyst with a fluorine content of 3.1% by weight, obtained in the same manner as above, was used.

In Comparative Example 7, an alumina boria (B20z: 20M mass %) catalyst with a fluorine content of 2.6% by weight, obtained in the same manner as above, was used.

Table 3 shows the results of the same tests as in Example 1 except that these catalysts were used and the LH5V and reaction temperature were changed. As is clear from Table 3, the yield of diisopropylnaphthalene, especially 2°6-diisopropylnaphthalene, was low in each comparative example.

Fluorine-containing aluminas similar to those used for the alkylation of benzene in the examples of the above-mentioned Japanese Patent Publication No. 42-3617 are very poor in the dialkylation of naphthalene, especially in the 2,6-dialkylation ( Comparative Example 5). The same also applies to the alumina-boria catalyst exemplified in the above-mentioned Japanese Patent Publication No. 42-3617 (Comparative Example 7).

[Example 9] To the same catalyst 1 [F (4°3% by weight) SiO2.Al2z 03 ] used in Example 2, β-isopropylnaphthalene and 1 times the mole of propylene were supplied to it. An alkylation reaction was carried out.

[Comparative Example 8] The same test as in Example 9 was conducted except that non-fluorinated SiO2.Al2203 was used as a catalyst.

The results of these tests are shown in Table 4.

Table 4 It is clear that the examples of the present invention are superior even when β-isopropylnaphthalene is used as the alkylated product.

[Example 101 The same catalyst I as used in Example 9 was supplied with α-isopropylnaphthalene and propylene in an amount of 1 mole to carry out an alkylation reaction.

[Comparative Example 9] The same test as in Example 10 was conducted except that non-fluorinated SiO2.A-β203 was used as a catalyst.

The results of these tests are shown in Table 5.

(The following is a blank space) Table 5 It is clear that the examples of the present invention are superior even when α-isopropylnaphthalene is used as the alkylated product.

In particular, even though α-isopropylnaphthalene was used as a raw material, the proportion of β-isopropylnaphthalene in unreacted isopropylnaphthalene increased, and the proportion of diisopropylnaphthalene also increased. The silica-alumina catalyst containing
It is clear that it has excellent not only alkylation but also transalkylation and isomerization abilities. This means that the target dialkylnaphthalene, especially 2
．． It was shown that the yield of the target product can be improved by recycling the mixture (mixture of naphthalene, mono-, di-, tri-, tetra-alkylnaphthalene, etc.) after separating and removing 6-dialkylnaphthalene to the reaction process. ing.

[Example 11] (Life test) The above catalyst I (SiO2/Al2 containing 4.3% by weight of F)
400 cc of O2) was charged into the bench reactor and LHSV
= 1.0 Hr-', pressure cuff, and the same alkylating agent as in Example 2 were supplied under the conditions of 0 Kg/cm''G, and a long-term life test was conducted.The reaction temperature was 2.
The temperature was increased stepwise from 55°C to 300°C.

As a result, the yield of 2,6-diituprobylnaphthalene was 13 mol% after 3100 hours from the start of the reaction.
I cut it.

[Comparative Example 10] (Life Test) Using the same silica-alumina catalyst as used in Comparative Example 1, a long-term life test was conducted under the same conditions as in Example 11.

As a result, the yield of 2,6-diitubrobylnaphthalene was 13 mol% after 2700 hours from the start of the reaction.
I cut it.

The yield and catalyst life of dialkylnaphthalene, especially 2,6-dialkylnaphthalene, are improved.

(2) The yield of the desired dialkylnaphthalene can be increased by recycling the reaction product after separation of the desired dialkylnaphthalene, particularly 2,6-dialkylnaphthalene.

Claims (3)

[Claims] (1) Silica containing 0.1 to 15% by weight of fluorine.
In the presence of an alumina catalyst, reaction temperature 200-450℃, reaction pressure 2-30Kg/cm^2G and LHSV 0.2-
Under the conditions of 10Hr^-^1, naphthalene and C_1~C
A raw material containing an alkylated substance selected from the group consisting of monoalkylnaphthalenes having an alkyl group of _4,
An alkylating agent selected from C_2 to C_4 olefins and a molar ratio of alkylating agent/alkylated object of 0.
A method for producing dialkylnaphthalene, which comprises contacting at a ratio of 1 to 10. (2) Silica containing 0.1 to 15% by weight of fluorine.
Naphthalene and C_
A raw material containing an alkylated substance selected from the group consisting of monoalkylnaphthalenes having an alkyl group of 1 to C_4 and an alkylating agent selected from olefins of C_2 to C_4 are combined into an alkylating agent/alkylated substance. Feed at a molar ratio of 0.1 to 10, at a temperature of 200 to 450°C,
Pressure 2~30Kg/cm^2G, LHSV0.2~10
The dialkylnaphthalene is reacted under conditions of 1 Hr^-^1, the desired dialkylnaphthalene is separated and recovered from the reaction product, and the reaction product after separation of the dialkylnaphthalene is circulated and fed to the reaction column. Production method. (3) Silica containing 0.1 to 15% by weight of fluorine.
A catalyst for producing dialkylnaphthalene, characterized by being made of alumina.