JPS6317815B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a method for producing o-alkylphenols by the reaction of phenols and olefins. Specifically, the present invention relates to a method for producing o-alkylphenols by the reaction of phenols and olefins. A method for producing o-alkylphenols. O-alkylphenols are used, for example, as antioxidants, stabilizers, etc., or as intermediates for thickeners and dyes. [Prior Art] A method for producing o-alkylphenol by reacting phenol and olefin in the presence of a catalyst is already known, and various catalysts have been proposed. For example, Japanese Patent Publication No. 39-5021 discloses a method using alumina as a catalyst. However, the method using alumina is an industrially preferable method because the catalyst is easy to handle, but the alumina catalyst has the drawbacks of rapid deterioration of activity and low phenol conversion rate. For example, a method using a catalyst prepared by adding sulfate to alumina (Tokuko Sho
46-3053) and a method of adding a specific amount of water to the reaction system (Japanese Patent Publication No. 52-9663), but neither of these methods could be considered a satisfactory solution. [Problems to be Solved by the Invention] In view of the above-mentioned circumstances, the present inventors reacted phenol and olefin using an alumina catalyst.
In producing alkylphenols, an investigation was conducted with the aim of searching for a method that suppresses by-products and has a high yield. In particular, when using propylene or n-butene as the olefin, various studies have been conducted on methods to achieve the above objective, and it has been found that the yield and selectivity are affected by the preparation method of the alumina catalyst, and that aluminum alkoxide The present invention was achieved by finding that alumina prepared as a raw material gives the best results. [Means for Solving the Problems] According to the present invention, the object of the present invention is to produce an o-alkylphenol by reacting a phenol and an olefin in a liquid phase in the presence of a catalyst. This is achieved by using alumina prepared by hydrolyzing aluminum alkoxide and calcining the obtained hydroxide. The present invention will be explained in detail below. (Raw material) In the present invention, phenol and olefin are reacted, and as the raw material olefin, a C ₂ to C ₂₀ olefin is usually used. Specific examples include ethylene, propylene, α-butylene, β-butylene, isobutylene, α-amylene, γ-amylene, β-isoamylene, and the like. In particular, secondary olefins that produce secondary carbonium ions such as propylene or α-butylene (i.e., olefins represented by R ¹ −HC=CH−CR ² R ³ R ⁴ , where R ¹ to R ⁴ are hydrogen (meaning an atom or a hydrocarbon residue) is preferred. The amount of these olefins used is usually 0.2 to phenol.
~2.0 times molar. (Catalyst) The present invention requires, as a catalyst, the use of alumina prepared by calcining aluminum hydroxide obtained by hydrolyzing aluminum alkoxide. Aluminum alkoxide, which is the starting material for the catalyst, usually has the general formula Al(OR) ₃ [R is C ₂ -
_C30 alkyl], specifically, for example, aluminum ethoxide, aluminum isopropoxide, aluminum-sec
-butoxide, aluminum-tert-butoxide, and the like. Hydrolysis of aluminum alkoxide is usually easily carried out by dispersing aluminum alkoxide in 3 to 500 moles of water at a temperature of 0 to 100°C. This treatment produces and precipitates aluminum hydroxide, and this precipitate is separately recovered according to a conventional method. Then, the obtained aluminum hydroxide was heated to 400 ~
0.1-20 at a temperature of 1000℃, preferably 500-700℃
The catalyst of the present invention can be obtained by calcining for about an hour. The catalyst of the present invention is usually used in powder or granule form. In addition, the amount of catalyst used varies depending on the reaction type and other conditions, but for example, when carrying out the reaction in a suspended bed type, it is usually the case that the amount of catalyst used is
It is 0.001 to 0.3 times the weight. (Reaction conditions) The reaction temperature in the present invention varies somewhat depending on the olefin used. For example, when using a secondary olefin, it is usually 150 to 400°C, preferably
The temperature is 180 to 300°C, and if this temperature is too low, the reaction rate will be slow, and if it is too high, by-products will be produced in large quantities, which is not preferable. In addition, the reaction pressure needs to be higher than the pressure at which the raw material phenol can maintain a liquid phase at the reaction temperature, but it is usually 2 to 50 kg/cm ²
It is. For example, when the reaction is carried out using a suspended catalyst bed, the reaction time is usually about 0.5 to 50 hours. Further, in the present invention, it is not preferable that the water concentration in the reaction system is too high, and it is usually preferable to maintain the water concentration in the liquid phase in the reaction system at 1000 ppm or less. Although the reaction of the present invention can be carried out in a batch, semi-continuous or continuous manner, it is usually carried out by passing a mixture of phenol and olein through a fixed bed packed with a catalyst under reaction conditions, or A method of suspending a catalyst therein, supplying olefin under reaction conditions, and allowing the reaction to occur for a predetermined period of time is adopted. Note that although the reaction of the present invention is usually carried out without using a special solvent, any organic solvent may be used if necessary. (Post-reaction treatment) The mixture after the reaction is usually separated by an excessive method when a catalyst is present, and then the mixture is distilled by a conventional method to obtain the target o-alkylphenol. can be recovered. [Effect] The alumina catalyst prepared by calcining aluminum hydroxide obtained by hydrolysis of aluminum alkoxide used in the method of the present invention has high activity and o-
The selectivity of alkylphenol is high, and the desired o-alkylphenol can be obtained in high yield. The effect of the catalyst of the present invention is demonstrated by conventional alumina catalysts, such as those shown in the specific examples of Japanese Patent Publication No. 39-5021 or 52-9663, which are prepared by firing aluminum hydroxide obtained from an aluminum salt of an inorganic acid as a raw material. It is clear from the Comparative Examples described later that this is much superior to the case where alumina containing carbon dioxide is used as a catalyst. [Examples] Hereinafter, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to the following Examples unless the gist thereof is exceeded. Examples 1-2 and Comparative Examples 1-6 5.0 g of phenol was placed in a closed reactor consisting of a 50 ml micro cylinder with a 100 ml space at the top.
(0.053 mol), 0.053 mol of propylene, and 0.27 g (0.0027 mol) of the alumina catalyst shown in Table 1, the reactor was shaken in an oil constant temperature bath and reacted under the conditions shown in Table 1. I did this. After the reaction, the mixture was analyzed by gas chromatography to determine the conversion rate of the raw material phenol,
The yield of the target product o-isopropylphenol (abbreviated as OIPP in the table) and the yield of the by-product 2,6- or 2,4-diisopropylphenol (abbreviated as DIPP in the table) were determined. However, the results are shown in Table 1. The catalyst used in the reaction was prepared by the following method. Catalyst A: Aluminum alkoxide produced by chain growth and oxidation of triethylaluminum
_{Commercially available} boehmite ( _PURAL-
SB: (Condea Chemie)
(manufactured by Komatsu Ltd.) in the air at 600℃ for 4 hours. Catalyst B: Commercially available reagent aluminum isopropoxide (manufactured by Tokyo Kasei Co., Ltd.) 200g and 10 times the amount of water about 2
After the isopropanol is distilled off, it is dried at 120°C and calcined at 660°C for 4 hours in air. Catalyst C: Commercially available reagent aluminum nitrate (Al
(NO ₃ ) ₃・9H ₂ O; Kanto Kagaku Co., Ltd. special grade) 250g is dissolved in about 1 part water. Add 10wt% ammonia water dropwise to this solution while stirring until the pH reaches 7 to neutralize it. The produced aluminum hydroxide was aged overnight, then filtered,
Wash with water, dry at 120℃ for 5 hours, dry at 500℃,
Bake in air for 4 hours. Catalyst D: A sodium aluminate aqueous solution obtained by the Bayer method was hydrolyzed with carbon dioxide gas, and then
After the gibsite obtained by drying the obtained precipitate is molded, it is fired in air at 700° C. for 3 to 4 hours. Catalyst E: Aluminum sulfate (Al ₂ (SO ₄ ) ₃・14−
18H ₂ O; special grade manufactured by Kanto Kagaku Co., Ltd.) 200g to about 1 part water
10wt% ammonia water is added dropwise to this solution until the pH reaches 7 to neutralize it. The produced aluminum hydroxide is thoroughly washed with a large amount of water, dried at 120°C, and calcined at 600°C for 4 hours in air. Catalyst F: Commercially available boehmite (manufactured by Kaiser Aluminum & Chemical Corporation) by the Bayer method was calcined in air at 660°C for 4 hours.

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Claims (1)

[Claims] 1. Phenol and olefin in the presence of a catalyst,
In producing o-alkylphenol by reacting in a liquid phase, alumina prepared by calcining aluminum hydroxide obtained by hydrolyzing aluminum alkoxide is used as a catalyst. Method for producing o-alkylphenol. 2. The method according to claim 1, wherein the olefin is a secondary olefin. 3. The method according to claim 1, wherein the aluminum hydroxide is fired at a temperature of 400 to 1000°C.