JPS62246532A - Alkylation of phenol - Google Patents

Abstract

PURPOSE:In the alkylation of phenol with an alcohol, the reaction is effected in liquid phase using Y-zeolite containing palladium and nickel or the like to enable the dominant production of p-alkylated product in high efficiency suppressing the meta-alkylation. CONSTITUTION:In the alkylation of a phenolic compound such as phenol with an alcohol and/or an ether such as diethyl ether, the reaction is carried out in the presence of a Y-type zeolite catalyst containing a) at least one selected from Ni, Co, Cu, Zn or Ag, preferably Ni and b) palladium to suppress the formation m-alkylated product which is difficult to be separated and produce p-alkylated phenol such as p-ethylphenol dominantly which is used as a feedstock for antioxidants and synthetic resins. Moreover, stabilized catalyst performance is maintained for a log period of time.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method for alkylating phenols. More details: Phenols? This invention relates to a method for efficiently synthesizing a para-alkylated product by suppressing alkylation at the meta-position and performing alkylation with an alcohol or (and) ether in a liquid phase in the presence of a specific catalyst.

Alkylphenols obtained by selectively arylating the oron and para positions of phenols such as phenol or substituted phenols.

It has important industrial uses. Among them, p-alkylphenols such as p-cresol and p-ethylphenol are antioxidants.

It occupies an important position as an intermediate raw material for synthetic resins and other products.

(Prior Art) The most common method for synthesizing these 5tc alkylphenols is to alkylate phenols with olefins using solid acid catalysts, Friedel-Krach catalysts, and the like.

On the other hand, as a method for introducing relatively short-chain alkyl groups into phenols, the alkylation method using alcohol is also an old method (
known from. In addition to the usual method using an amorphous solid acid catalyst, there is also a gas phase alkylation method using a zeolite catalyst. A method using a zeolite catalyst is the gas phase alkylation of phenol using isopropanol.
- A method as described in U.S. Pat. No. 4,391,998 using a ZSM-5 catalyst, and a method as described in U.S. Pat. Are known. In addition, using Y-type zeolite catalyst with solid acidity, phenol and methanol can be mixed in the gas phase. react,
A method for producing p-cresol was published in Japanese Patent Publication No. 52-121.
It is described in No. 81. Here, the catalysts include HY type zeolite, alkali metals, alkaline earth metals, and rare earths.

Copper, zinc, cadmium, chromium, manganese, cobalt,
Y-type zeolites ion-exchanged with transition metals such as nickel have been proposed, and among them, HY-type zeolites are p-
It is described that it is suitable for producing cresol, that as the acidic point of zeolite decreases, the selective production of p-cresol decreases, and that gold MY type zeolite is rather suitable for producing anisole.

(Problems to be Solved by the Invention) Among the above-mentioned known methods, the method of alkylating phenols with olefins can synthesize para-alkylated products in good yield when the alkylating agent is a branched olefin. . However, when the alkylating agent is a low molecular weight linear olefin, a mixture of isomers is produced and the yield of useful para-alkylated product is low. For example, when phenol is alkylated using ethylene.

0-ethylphenol, m-ethylphenol.

A mixture of p-ethylphenol is produced. The boiling points of the above three isomers of ethylphenol are 204°C for the ortho form, 214°C for the meta form, and 218°C for the para form.
The difference in boiling point between the ortho form and the para form is relatively large, so it is suitable for rectification.

separation is possible. However, when the meta body coexists, n1 of the para body is close to the boiling point of the para body.
11 separation becomes very difficult. The formation of the meta-form is a serious drawback, not only resulting in a decrease in the yield of the para-form, but also making it extremely difficult to separate the para-form in this way.

- What is the usual method of using an amorphous solid acid catalyst in alkylation reaction with alcohol?

An isomer mixture consisting mainly of ortho-alkylated products is produced, and the yield of para-alkylated products is generally extremely low.

Further, as described in the above-mentioned US Pat. No. 4,391,998, the method of gas-phase alkylation of phenol with isopropanol using an H-ZSM-5 catalyst is a method using amorphous silica-
Compared to the method using an alumina catalyst, the selectivity for producing p-impropylphenol and vinpropylphenol is higher, but a large amount of difficult-to-separate isomers such as 1m-impropylphenol and n-propylphenol are produced as by-products.

This was insufficient as an industrial method.

Furthermore, as described in the above-mentioned US Pat. No. 4,532,368, the method of vapor phase alkylation with phenolic ethanol using a ZSM-5 catalyst modified with phosphorus produces a mixture of isomers centered on 1m-ethylphenol. Therefore, it could not be said to be a one-selective alkylation method.

The method of vapor phase alkylation of phenol with methanol using a HY type zeolite catalyst as described in Japanese Patent Publication No. 52-12181 mentioned above has a high yield of p-cresol;
It also has the excellent feature that the amount of m-cresol produced is very small. However, reports on this reaction (C
analysis by zeolites, El
sevierScientificPublish
ing Company.

Amslerdam, 1980, 105-111
According to Page), catalyst performance changes significantly over time, with the phenol conversion rate decreasing by about 20% per hour.
It was still insufficient as an industrial method.

An object of the present invention is to solve the problems of the above-mentioned known techniques. That is, the present invention aims to provide a method for alkylating phenols that can produce alkylated products at para-position in good yield without producing alkylated products at meta-position, which are difficult to separate, and can maintain stable catalyst performance for a long time. purpose.

(Means for Solving Problems) As a result of intensive research aimed at achieving the above object, the present inventors have found that (1) nickel, We have found that the problem can be solved by reacting one or more selected from cobalt, copper, zinc, and silver in a liquid phase using a Y-type zeolite containing (21/<radium) as a catalyst.

The raw material phenols used in the alkylation method of the present invention are those that can be alkylated at least at the para or ortho position of the hydroxyl group, and therefore hydrogen atoms at the para or ortho position or at the para and ortho positions. It has the following.

Such phenols may have various nuclear substituents. Specific examples include phenol, cresol, xylenol, ethylphenol, flobylphenol, butylphenol, octylphenol, and nonylphenol.

Examples include hydrocarbon derivatives such as dibutylphenol, cyclohexylphenol, phenylphenol, and cumylphenol, and halogenated phenols such as chlorophenol, bromophenol, and dichlorophenol.

In the process of the invention, alcohols or/and ethers are used as alkylating agents.

The alcohols used in the present invention include primary or secondary alcohols having 1 to 12 carbon atoms. Specific examples include methanol, ethanol% 1-propertool, 2-propertool.

Examples include 1-butanol, 2-butanol, octatool, decanol, dodecanol, cyclohexanol, and benzyl alcohol. Also.

The ethers used in the present invention are of the type obtained by intermolecular dehydration of the alcohols described above, and specific examples include dimethyl ether, diethyl ether, di-11-propyl ether, diisopropyl ether, ')-n-
Examples include 7"f ether and diisobutyl ether.

The alkylating agent in the process of the invention may be either an alcohol or an ether, or any mixture of both. When carrying out the process of the present invention using alcohol as an alkylating agent, a portion of the alcohol may be converted to ether in the course of one reaction. In such cases, the mixture of alcohol and ether can be recovered and both can be reused as alkylating agents. , one or more selected from silver, and (2) palladium and tY! It contains Y-type zeolite. As the metal (1), nickel, cobalt and zinc are preferred.

Copper and silver have the same effects as these metals, but there are many variations in reaction results and there are problems with reproducibility of reaction results. Preferably, it is deposited in the Y-type zeolite by an ion exchange operation or an impregnation operation, or by mixing it during zeolite synthesis. After the metal has been deposited, it can be fixed in place by reduction to the elemental metal form or by oxidation by burning. The preferable range of the content of the above metals in the Y-type zeolite varies depending on the type of metal, but 1
For example, the total amount of metal in the original state is in the range of about 0.1 to about 15% by weight, more preferably about 0.2 to about 10% by weight. Palladium is effective when added in a very small amount, but about 0.01% of the metal
Preferably it accounts for a range of 5% by weight, especially 0.05-3% by weight.

In the present invention, the YW zeolite may contain other metals as well as the metals described above. As other metals, alkali metals and alkaline earth metals are preferred.

Particularly preferred are lithium, sodium, and potassium, which belong to alkali metals. However, replacing the ion exchange points of Y-type zeolite with hydrogen, that is, forming the structure of HY-type zeolite and adding acidic points, increases the amount of by-products of etherified phenols and This is not a good idea as it reduces the yield of the alkylated product.

In the method of the present invention, it is preferable to adjust the charging ratio of raw material phenols and alkylating agent in advance to carry out the reaction. What is the preparation ratio?

A range of 0.1 to 10 moles of alcohol or (and) ether per mole of phenol is appropriate, and a range of 0.5 to 5 moles is particularly preferred.

The process of the invention is carried out in the liquid phase of the alkylation reaction. Therefore, it is necessary to carry out the reaction under pressure at which the raw material phenols and the alkylating agent do not substantially vaporize and escape. Suitable reaction pressures are generally from naturally occurring pressure to about 150 atmospheres.

Particularly preferred is a naturally occurring pressure to about 120 atmospheres.

When the reaction is carried out under a pressure higher than the naturally occurring pressure, it is possible to pressurize with an inert gas such as nitrogen, or with hydrogen gas.

The reaction temperature can usually be selected within the range of 100 to 400℃, but 1
The temperature is preferably 200 to 320°C in terms of scheelite rate and selectivity.

In the present invention, the alkylation reaction can be carried out either batchwise or continuously. As continuous methods, fixed bed, suspended bed or fluidized bed methods are possible. For example, when performing a patch reaction using powdered axes,
The amount of catalyst used is about 2% to about 401:8% of the raw material phenols.
A range of 0.2 to 5 hours is appropriate, and the reaction is usually completed in 0.2 to 5 hours. In addition, in a fixed bed reaction using a ring-forming catalyst, the weight hourly space velocity (WH8V10.2~15
, preferably from 0.5 to 5, can be contacted with the feed stream.

(Function) When an alkylation reaction is carried out in the gas phase using the liquid phase alkylation catalyst of the present invention, it exhibits almost no catalytic activity, or the catalytic activity disappears after the reaction is continued for several hours. cannot be achieved. In addition, the special public service marked # is 52-1
According to No. 2181, in the gas phase alkylation method of phenol using methanol, it is stated that HYWY type zeolite catalyst is most suitable for producing p-cresol, and that zeolite catalyst for metal Y is rather suitable for producing anisole. However, the liquid phase alkylation method of the present invention exhibits a completely opposite tendency.

That is, according to the liquid phase alkylation method of the present invention, HY
The Y-type zeolite catalyst produces a large amount of etherified products of phenols such as anisole, but the yield of alkylated products is low; on the contrary, the Y-type zeolite containing the metal described in the present invention exhibits good catalytic performance. In the method, (1) nickel, cobalt, copper, and zinc are contained in the Y-type zeolite.

One or more selected from silver and (2) palladium act synergistically to increase the selectivity of alkylation at the para-position, and at the same time improve the selectivity of heavy substances mainly consisting of crosslinked products of phenols. Effect of suppressing generation? manifest. this is,
This is a characteristic that cannot be observed in a catalyst containing only any one of the ten thousand metals in the tY-type zeolite.

(Effects of the Invention) According to the method of the present invention, it is possible to obtain a para-alkylated product in high yield with less heavy by-products and no or almost no meta-alkylated product that is difficult to separate. I can do it. Also.

When alkylated by the method of the present invention, stable catalyst performance can be maintained for a long period of time, so that the catalyst can be used repeatedly in batch reactions, for example, and can be used continuously for long periods in continuous reactions.

(Examples and Reference Examples) The present invention will be explained in more detail below using Examples and Reference Examples, but the present invention is not limited to the Examples.

Tsu 11'! 111-3 (1) Catalyst (commercially available powdered NaY-type zeolite) I: Linde crack 5K-40: Composition (wt%) SiO□; 64°A
l2O3”23. Na20=13; (molar ratio)
Si02/A1203=4.7. Na2O/A1
203=0.93) xoo, 9 was dispersed in 1 ffl constant sodium chloride aqueous solution 1.51 and heated in a constant temperature bath at 80° C. for 8 hours. Then, it was dispersed in 1 N aqueous nickel acetate solution and heated in a constant temperature bath at 80° C. for 2 hours. The nickel acetate aqueous solution was renewed and the same ion exchange operation was performed a total of three times, followed by thorough washing with water, drying at 120°C, and further calcining at 430°C for 3 hours to prepare NiY-type zeolite. Analysis value by atomic absorption spectrometry (weight%)
is, Ni =9.0. Na=2.4. The above NiY type zeolite was impregnated with water in which 1.24% of tetramine dichloropalladium hydrate and P was dissolved.
The mixture was dried at 430° C. for 3 hours to produce a NiY-type zeolite catalyst containing 0.5% Pd.

Cobalt acetate instead of nickel acetate.

Co Y
, Zn Y W zeolite was prepared. In addition, these were treated with tetramine dichloropalladium aqueous solution in the same manner as above, and 0.5% Pd-CoY and 0.5% Pd
- ZnY type zeolite fibers were completely prepared.

(2) Alkylation reaction In a 5US316 autoclave with a capacity of 100 m/m equipped with heating and stirring equipment, add the catalyst prepared by the above method, 20.31 phenol and 1 ethanol.
9-7.9, and after purging the system with nitrogen gas, the temperature was raised to 250°C while stirring.

(3) Results The reaction was carried out at 250° C. for 2 hours, and the reaction was performed using the composition shown in Table 1 (excluding the alkylating agent).

Reference Examples 1 to 3 Alkylation reactions were carried out in the same manner as in Examples 1 to 3, except for the above, to obtain reaction solutions having the compositions shown in Table 2 (excluding the alkylating agent).

Reference Example 4 The same NaY used as the raw material for catalyst preparation in Actual Examples 1 to 3
type zeolite) 100. ! Disperse in 1.5j of il'kl specified sodium nitrate aqueous solution and incubate at 80°C @ warm bath.
heated for an hour. After washing with water, add 1.24 N of tetramine dichloropalladium hydrate in water? impregnated, 120
The mixture was dried at 430° C. for 3 hours to produce a NaY-type zeolite catalyst containing 0.5% Pd.

The alkylation reaction was carried out in the same manner as in Examples 1 to 3 except that the above 0.5% Pd-Na Y-type zeolite catalyst was used to obtain a reaction solution having the composition shown in Table 2 (excluding the alkylating agent). Ta.

Reference Examples 1 to 3 using catalysts that do not contain palladium (
In Table 2), there were more heavy by-products than in Examples 1 to 3 (Table 1) using palladium-containing catalysts. on the other hand,
The catalyst of Reference Example 4 (Table 2) containing only palladium has lower activity than the catalysts of Actual Examples 1 to 3 (Table 1).

Practical Example 4 Into the same autoclave as used in Examples 1 to 3, 5 g of the 0.5% Pd-N1Y type zeolite catalyst of Example 1 and 19.7.9 g of phenol in 20.31 ethanol were added.
The reaction was carried out at 250°C for 2 hours.

After finishing the scour, the catalyst was collected in a glass filter, washed with ethanol, and then reused.

When the same catalyst was collected and reused 21 times in this manner, almost no change in catalyst performance was observed.

Practical Example 5 In the same autoclave as used in Examples 1 to 3, 0.5% Pd-N1YW zeolite catalyst of Example 1 was added with 5JF,
Phenolic 20.3.9. 20.9 methanol was added and reacted at 300°C for 2 hours.

The composition of the reaction solution (excluding the alkylating agent) was as shown in Table 3.

Reference Example 5 The material used as a raw material for catalyst preparation in Examples 1 to 3 was heated in a constant temperature bath at °C for 2 hours. After renewing the ammonium nitrate aqueous solution and repeating the same ion exchange operation a total of four times, the mixture was washed with water, and the inverter reaction was carried out at 120°C to obtain a reaction solution of Table 1-30 (excluding the alkylating agent). The HY type zeolite catalyst can produce anisole, but the yield of cresol is low.

Example 6 Into the same autoclave as used in Examples 1 to 3, 51% of the 0.5% Pd-N1Y type zeolite catalyst of Example 1 was added. 20.31% phenol and 189% diethyl ether were added and reacted at 250°C for 2 hours. The composition of the reaction solution (excluding the alkylating agent) was as follows.

Unreacted phenol 28.3 (wt%) 0-ethylphenol 12.6 m-ethylphenol 0.1 p-ethylphenol 24.5 Diethylphenols 7.1 Phenetol 16.5 Ethylphenetol 5.0 Weight matter 5.9 j; jl,, -...

Claims (1)

[Claims] 1. In alkylating phenols with alcohol or (and) ether, (1) one or more selected from nickel, cobalt, copper, zinc, and silver; and (2) palladium. A method for alkylating phenols, characterized in that the reaction is carried out in a liquid phase using Y-type zeolite containing as a catalyst. 2. The method according to claim 1, wherein the metal represented by (1) is one or more selected from the group consisting of nickel, cobalt, and zinc. 3. The method according to claim 1, wherein the catalyst is Y-type zeolite containing nickel and palladium. 4. The method according to any one of claims 1 to 3, wherein the phenol is phenol. 5. The method according to any one of claims 1 to 4, wherein the alcohol or (and) ether is ethanol or (and) diethyl ether.