JP6294798B2 - Method for reducing hydroxyacetone in crude phenol, method for producing crude phenol with less hydroxyacetone and method for producing high purity phenol - Google Patents

Description

  The present invention relates to a method for reducing hydroxyacetone (hereinafter also referred to as “HA”) in crude phenol, a method for producing crude phenol with less HA, and a method for producing high-purity phenol, and more particularly by cumene method. The present invention relates to a method for reducing HA in crude phenol, a method for producing crude phenol with less HA, and a method for producing high-purity phenol, which are useful in the method for producing phenol.

  In the phenol production method by cumene method, a step of oxidizing alkylbenzene to alkylaryl hydroperoxide, a step of concentrating the oxidation reaction product of alkylbenzene, a step of cleaving (decomposing) the concentrated solution into phenol and ketone with an acid catalyst, Phenol is produced through a step of neutralizing the acid cleavage product (acid decomposition product) and a step of distilling the neutralized acid cleavage product (acid decomposition product) to separate it into phenol and impurities. .

  When the alkylbenzene is cumene, the acid cleavage product (acid decomposition product) is mainly composed of phenol and acetone, in addition to α-methylstyrene, acetophenone, cumylphenol, 2-phenyl-2-propanol. (Also known as α-dimethylphenylcarbinol), trace amounts of hydroxyacetone (HA), α-phenylpropionaldehyde (α-PPA) and other by-products such as various carbonyl compounds and unreacted cumene. ing.

  Phenol is derived, for example, from diphenylolpropane (also known as bisphenol A), and polycarbonate and the like are produced using this diphenylolpropane as a raw material. In these fields of use, high-purity phenol is required.

  In order to obtain high-purity phenols, neutralized products of acid cleavage products (acid decomposition products), low-boiling substances such as acetone, cumene, water, α-methylstyrene, acetophenone, 2-phenyl-2-propanol, etc. From the phenol fraction obtained by removing most of the high-boiling substances by fractional distillation, aliphatic carbonyl compounds such as HA and aromatic carbonyl compounds such as α-phenylpropionaldehyde are further removed. Among the compounds, HA is particularly difficult to remove by distillation separation from phenol, which deteriorates the quality of product phenol.

  In a conventional method for producing high-purity phenol, a method is known in which HA is reacted with phenol using a solid acid catalyst to facilitate separation by distillation. For example, by bringing crude phenol (containing 200 ppm of HA) into contact with an activated alumina catalyst at 360 ° C., HA is reacted with phenol to give 2-methylbenzofuran (2-MBF), and then steam and phenol are separated from 2-methylbenzofuran. It has been proposed (Patent Document 1). In addition, a method has been proposed in which a crude phenol is brought into contact with a silica / alumina catalyst at 150 to 250 ° C. to convert the carbonyl compound, which is an impurity, into another compound and then separated from phenol by distillation (Patent Document 2). In addition, a method has been proposed in which crude phenol containing no water is brought into contact with an acidic ion exchange resin catalyst at 80 to 150 ° C., and an carbonyl compound as an impurity is converted into another compound, followed by distillation separation from phenol (Patent Document 3). ). However, in these methods, phenol and α-methylstyrene, which are useful components in the crude phenol, react with impurities, or each react with each other or independently to form cumylphenol or an olefin dimer. And the useful component disappears in vain.

  As a method for removing HA so that an active ingredient is not lost, a method of contacting HA with a base catalyst is known. HA is converted to a compound having a higher boiling point than HA (hereinafter also referred to as “high-boiling compound”) by aldol condensation with a base catalyst, and the high-boiling compound can be easily separated from phenol by distillation. As such a method, there is a method in which an aqueous phase obtained by oil-water separation of the neutralized product of the acid decomposition product is brought into contact with a base catalyst. That is, after acid decomposition of cumene hydroperoxide, when neutralizing the acid catalyst with an aqueous sodium hydroxide solution, about half of the HA is distributed to the aqueous phase, so the HA of this aqueous phase is converted to a homogeneous base such as NaOH. The catalyst is brought into contact with a solid base catalyst such as an anion exchange resin or Na exchanged Y-type zeolite (Patent Document 4). However, this method has a problem that a large amount of HA distributed in the oil phase containing the crude phenol remains as it is. Therefore, there is also a method in which an oil phase containing crude phenol is brought into contact with a base catalyst. In this method, it is necessary to distill off a light boiling material such as acetone so that acetone does not lose due to reaction with the base catalyst, and then contact the oil phase with the base catalyst (Patent Document 5, Patent Document 6, Patent Document 7). As the base catalyst used in the oil phase, a solid base catalyst is more advantageous than a homogeneous base catalyst that requires a neutralization step and an oil-water separation step again.

Japanese Examined Patent Publication No. 37-11664 Japanese Patent Publication No.42-12250 British Patent No. 1231991 US Pat. No. 6,066,767 JP 2000-226352 A JP 2005-521739 A US Patent Application Publication No. 2007/0244346

  However, as a result of researches by the present inventors, when HA distributed in the oil phase is brought into contact with a solid base such as Na-exchanged Y-type zeolite or hydrotalcite, the quality of phenol is greatly adversely affected, and distillation is performed in the same manner as HA. It was found that acetoin, which is difficult to separate from phenol, was newly produced as a by-product.

  In view of such problems in the prior art, the present invention is a method for producing crude phenol containing HA as an impurity, for example, cumene hydroperoxide, after acid decomposition and neutralization treatment to separate acetone in a cumene method phenol production method. Providing a method for reducing HA without losing phenol or producing a large amount of acetoin from crude phenol, providing a method for producing crude phenol with less HA, and having high HA and acetoin It is an object of the present invention to provide a method for producing a high-purity phenol and a method for producing a high-purity bisphenol containing less HA and acetoin.

  As a result of intensive studies to solve the above problems, the present inventors have used a certain solid base catalyst, without producing a large amount of acetoin that deteriorates phenol quality, and without losing phenol. The present inventors have found that hydroxyacetone contained as impurities in the crude phenol can be reduced and have completed the present invention.

That is, the gist of the present invention is the following [1] to [12].
[1]
A solid containing at least one of a crude phenol containing hydroxyacetone, a weakly basic solid base catalyst (i) containing a metal oxide, and a solid basic catalyst (ii) containing a basic zeolite having a linear pore structure A method for reducing hydroxyacetone in crude phenol, comprising a conversion step of contacting the base catalyst (A) to convert the hydroxyacetone to a high-boiling compound.

[2]
The solid base catalyst (A) includes the solid base catalyst (i), and the solid base catalyst (i) is an oxide (1) of a group IIA or IIIB metal element, or a group IA or IIA metal element. The method for reducing hydroxyacetone in the crude phenol as described in [1] above, wherein the oxide is supported on silica gel (2).

[3]
The solid base catalyst (A) contains the solid base catalyst (ii), the solid base catalyst (ii) has a linear pore structure and contains a metal element of Group IA or IIA The method for reducing hydroxyacetone in the crude phenol according to the above [1], which is zeolite (3).

[4]
The solid base catalyst (A) includes the oxide (1) of the group IIA or IIIB metal element, and the oxide (1) of the group IIA or group IIIB metal element is selected from yttrium oxide and magnesium oxide. The method for reducing hydroxyacetone in the crude phenol according to the above [2], which is at least one kind.

[5]
The method for reducing hydroxyacetone in the crude phenol according to the above [3], wherein the zeolite used for the basic zeolite (3) is an 8- to 12-membered ring zeolite.

[6]
The method for reducing hydroxyacetone in the crude phenol as described in [3] above, wherein the zeolite used for the basic zeolite (3) is at least one selected from ferrierite, mordenite and ZSM-5.

[7]
The conversion step is performed under conditions of 100 to 300 ° C. and atmospheric pressure to 3 MPa, and hydroxyacetone in the crude phenol according to any one of the above [1] to [6] is reduced. Method.

[8]
The method for reducing hydroxyacetone in the crude phenol according to any one of the above [1] to [7], wherein an increase amount of acetoin concentration (weight basis) in the crude phenol in the conversion step is 20 ppm or less.

[9]
A method for producing a crude phenol with less hydroxyacetone, comprising a step of reducing hydroxyacetone from a crude phenol containing hydroxyacetone by the method according to any one of [1] to [8] above.

[10]
Including a step of reducing hydroxyacetone from a crude phenol containing hydroxyacetone by the method according to any one of [1] to [8] above, and a step of removing the high boiling point compound by distillation. To produce high purity phenol.

[11]
The manufacturing method of bisphenol characterized by including the process of manufacturing high purity phenol by the manufacturing method as described in said [10], and the process of manufacturing bisphenol using the said high purity phenol as a raw material.

[12]
Oxidation of alkylbenzene to alkylaryl hydroperoxide a.
A step b of concentrating the alkylbenzene oxidation reaction product obtained in the step a to obtain a concentrated liquid;
A step c in which an alkylaryl hydroperoxide contained in the concentrate is cleaved with phenol and a ketone in the presence of an acid catalyst to obtain an acid cleavage product;
A process for producing high-purity phenol by a cumene method, comprising a step d of neutralizing the acid cleavage product, and a step e of distilling the neutralized acid cleavage product into phenol and impurities,
The step e is a step of preparing a crude phenol containing hydroxyacetone by removing at least a part of a light fraction from the neutralized acid cleavage product, and the above [1]- [8] A method for producing high-purity phenol by a cumene method, comprising a step of reducing hydroxyacetone by the method according to any one of [8] and a step of removing the high boiling point compound by distillation.

  According to the present invention, hydroxyacetone in crude phenol can be reduced without producing a large amount of acetoin and suppressing the disappearance of phenol and α-methylstyrene, which are useful components, and further, hydroxyacetone In addition, crude phenols, high-purity phenols and bisphenols with low acetoin can be produced.

Hereinafter, the present invention will be described in more detail.
[Method for reducing hydroxyacetone in crude phenol]
The method for reducing hydroxyacetone in the crude phenol according to the present invention (hereinafter also referred to as “HA reduction method according to the present invention”) includes a crude phenol containing hydroxyacetone, a solid base catalyst (i) and a solid described later. It has the conversion process which contacts the solid base catalyst (A) containing at least 1 type of a base catalyst (ii), and converts a hydroxyacetone into a high boiling point compound. In addition, the crude phenol before contacting with the solid base catalyst (A) is hereinafter also referred to as “untreated crude phenol”.

  The method for reducing HA according to the present invention can be applied to a method for producing phenol by the cumene method. As described above, the method for producing phenol by the cumene method is a step of oxidizing alkylbenzene (eg cumene) to alkylaryl hydroperoxide (eg cumene hydroperoxide), and concentrating the oxidation reaction product of alkylbenzene obtained in the above step. The step of obtaining a concentrated solution, the step of cleaving the alkylaryl hydroperoxide contained in the concentrated solution into phenol and ketone with an acid catalyst to obtain an acid cleavage product, the step of neutralizing the acid cleavage product, Phenol is produced through a process of distilling the acid cleavage product after the summation to separate it into phenol and impurities. The residue obtained by removing most of the light fraction (for example, acetone, cumene, α-methylstyrene) from the acid cleavage product after neutralization (hereinafter also referred to as “crude phenol in cumene method”) is used in the present invention. This corresponds to the untreated crude phenol used in the method for reducing HA, and can also be used as a raw material for the method for producing high-purity phenol according to the present invention described later.

  In addition to phenol, the raw crude phenol contains components to be separated from phenol and removed, that is, impurities. The content of phenol in the untreated crude phenol is usually 80 to 99% by weight, preferably 85 to 99% by weight.

The untreated crude phenol may further contain a carbonyl compound contained in the crude phenol in the cumene method in addition to HA as an impurity.
Examples of the carbonyl compound include aromatic carbonyl compounds and aliphatic carbonyl compounds. Examples of the aromatic carbonyl compound include α-phenylpropionaldehyde (α-PPA), acetophenone (Anone), benzaldehyde (BAD), and the like. Examples of the aliphatic carbonyl compound include HA and mesityl oxide (MO). The untreated crude phenol may contain one type of carbonyl compound other than HA, or may contain two or more types. The method for reducing HA according to the present invention includes the untreated crude phenol, HA as an aliphatic carbonyl compound, mesityl oxide (MO) and / or α-phenylpropionaldehyde (α-PPA) as an aromatic carbonyl compound. It is effective when a crude phenol containing as an impurity is used.

The content of the carbonyl compound (including HA) in the untreated crude phenol is usually 1 to 20% by weight, preferably 1 to 15% by weight.
The impurities other than the carbonyl compound contained in the crude phenol vary depending on the method of producing the crude phenol, and are not particularly limited. For example, acetone, α-methylstyrene, cumylphenol, 2-phenyl-2-propanol, α -Methylstyrene dimer (2,4-diphenyl-4-methyl-1-pentene), unreacted raw materials used for the production of crude phenol, and the like. These impurities are generally easier to separate and remove from phenol than the carbonyl compounds. These impurities may be removed from the untreated crude phenol by distillation or the like.

When impurities other than the carbonyl compound are contained in the untreated crude phenol, the content is usually 0.9 to 20% by weight, preferably 0.9 to 10% by weight.
The composition of the “crude phenol in the cumene method” is exemplified as follows. In addition, the said composition range is for the purpose of illustration to the last, Comprising: The technical scope of this invention is not restrict | limited at all.
Phenol 87.0-95.6 wt%
Cumene 1.0-0.1% by weight
α-Methylstyrene 2.0-0.1% by weight
Hydroxyacetone 0.5-0.1% by weight
α-Phenylpropionaldehyde 0.5 to 0.1% by weight
Acetophenone 4.0-2.0% by weight
2-Phenyl-2-propanol 1.0-0.5% by weight
Other high boiling point components 4.0 to 1.5% by weight

  The above cumene and α-methylstyrene can be separated from phenol as a light fraction, and acetophenone, 2-phenyl-2-propanol and other high-boiling components can be separated from phenol as a heavy fraction by distillation.

  Among the above impurities, α-methylstyrene is an industrially useful substance, and thus is preferably separated and removed from phenol in an industrially usable state. Acetophenone is also valuable as an industrial product.

<Solid base catalyst (A)>
The solid base catalyst (A) includes at least one of a weakly basic solid catalyst (i) containing a metal oxide and a solid basic catalyst (ii) containing a basic zeolite having a linear pore structure. Yes.

As the solid base catalyst (A), MgO and Y ₂ O ₃ described later are preferable from the viewpoint that the effect of reducing HA is particularly high. Further, from the viewpoint that the catalyst hardly disappears, a catalyst in which sodium oxide described later is supported on silica gel is preferable.

  The shape of the solid base catalyst (A) is not particularly limited, but tablets and noodles that are easily available industrially are recommended. Further, the size may be determined by the inner diameter of the reaction column used in the conversion step, and preferably has a circular diameter of 2 to 6 mm and a height (approximately The length in the direction perpendicular to the circular cross section) is about 2 to 6 mm.

(Weakly basic solid base catalyst containing metal oxide (i))
When the untreated crude phenol is brought into contact with a solid basic catalyst having strong basicity, first, a high boiling point compound having a complicated structure is formed while HA is accompanied by cyclization and dehydration reaction, and then derived from HA. It is considered that acetoin having a structure in which a methyl group is added to HA is generated by the decomposition reaction of the high boiling point compound. In experiments conducted by the present inventors, NaOH, which is a strong base catalyst of homogeneous system, was added to 1% HA aqueous solution so as to have a pH of 12, and when treated at 90 ° C. for 2 hours, 90% of HA was converted. It is known that as much as 4% acetoin is produced as a by-product in a molar ratio with respect to HA. The effect of acetoin on the quality of phenol is an order of magnitude greater than the effect of HA on the quality of phenol, especially in the hue test of phenol, and even if HA can be reduced if acetoin is produced, There is a case.

On the other hand, by using a weakly basic solid base catalyst (i) containing a metal oxide for the conversion reaction of HA to a high-boiling compound, HA can be reduced and the production of acetoin can be suppressed.
The weakly basic solid base catalyst (i) containing a metal oxide includes the following (1) oxides of group IIA or IIIB metal elements, and (2) oxides of group IA or IIA metal elements Is supported on silica gel.

(1) Group IIA or Group IIIB Oxides The solid base catalyst (i) includes group IIA or group IIIB metal element oxides, specifically, MgO, SrO, BaO, Se ₂ O _3. , Y ₂ O ₃ , CeO _{2 and the} like. Among these, MgO and Y ₂ O ₃ are preferable.

  The production method of Group IIA or Group IIIB oxide is not particularly limited, but impregnation method, initial wetting method, spray method, coprecipitation method, sol-gel method, thermal decomposition method (chloride, organic metal, organic acid salt) Etc.) or any other method. As the oxide precursor, those suitable for the metal oxide production method such as hydroxides, organic acid salts, carbonates, and nitrates can be used. For example, yttrium oxide can be produced by a method of decomposing yttrium hydroxide produced by a precipitation method or a coprecipitation method at a high temperature, a method of decomposing commercially available yttrium acetate, yttrium nitrate, yttrium carbonate, or the like at a high temperature.

(2) A catalyst in which an oxide of a Group IA or IIA metal element is supported on silica gel The solid base catalyst (i) includes a catalyst in which an oxide of a Group IA or IIA metal element is supported on silica gel. .

  Examples of Group IA oxides supported on silica gel include sodium oxide, potassium oxide, rubidium oxide, and cesium oxide. Among these, sodium oxide, potassium oxide, and cesium oxide are preferable from the viewpoint of basicity. Further, sodium oxide is more preferable.

  Examples of Group IIA metal element oxides supported on silica gel include magnesium oxide, calcium oxide, strontium oxide, and barium oxide. Among these, magnesium oxide and calcium oxide are preferable from the viewpoint of basicity. Further, magnesium oxide is more preferable.

The silica gel of the carrier is not particularly limited as long as it is commonly used as an adsorbent. For example, Experimental Chemistry Course 9, Synthesis and Purification of Inorganic Compounds (issued on December 20, 1958) , Maruzen Co., Ltd.) All silica gels produced by the six methods described on page 513 are mentioned. As the silica gel used in the present invention, a silica gel having a specific surface area of 50 to 900 m ² / g and a pore volume of 0.3 to 1.8 ml / g is preferable, and a specific surface area of 50 to ²⁰⁰ m ² / g is particularly preferable. Silica gel having a pore volume of 0.7 to 1.8 ml / g is more preferable. Such a silica gel may be prepared by a known method [for example, the method described in JP-A-9-30809 or Akazaki et al., Tosoh Research and Technical Report Vol. 45, 65-69 (2001)]. It may be a commercial product. An example of such a commercial product is CARJACT, which is a silica for a catalyst carrier manufactured by Fuji Silysia Co., Ltd., used in Examples described later.

  The method for supporting an oxide of a group IA or group IIA metal element on silica gel is not particularly limited, but a salt of a group IA or group IIA metal element (hydroxide, chloride, carbonate, organic acid salt, etc.) And a solution obtained by dissolving this salt in an organic solvent is impregnated into a silica gel carrier, and then baked to form an oxide of a Group IA or IIA metal element. Specifically, for example, a solution prepared by dissolving a sodium salt such as sodium acetate corresponding to a desired loading amount in water so as to have the same volume as the pore volume of the silica gel of the carrier is prepared, and this is added to a dropper or the like After impregnating with silica gel and drying, sodium oxide can be supported on the silica gel by baking at about 500 ° C. in an air stream.

  The amount of the Group IA or Group IIA oxide supported on the silica gel is not particularly limited, but in order to disperse them uniformly on the surface of the silica gel, it is usually 1 with respect to the total weight of the oxide and the silica gel. -30%, preferably 3-15%.

(Solid base catalyst containing basic zeolite with linear pore structure (ii))
Examples of the solid base catalyst (A) also include a solid base catalyst (ii) containing a basic zeolite having a linear pore structure. Examples of the zeolite include a zeolite having a linear pore structure and a basic zeolite (3) containing a group IA or group IIA metal element (that is, alkali metal or alkaline earth metal), The diameter at the entrance of the pore and the crystallographic diameter of the internal cavity are usually comparable.

  In the present invention, “zeolite having a linear pore structure” refers to a zeolite having tunnel-type one-dimensional pores as pores and a zeolite having two-dimensional pores intersecting the one-dimensional pores. The linear pore structure includes a pore structure having a partial strain or a zigzag structure. Further, although it is desirable that the diameter at the entrance of the pore and the crystallographic diameter of the internal cavity are approximately the same, the pore may be locally thick or thin.

  As described above, since acetoin has a structure in which a methyl group is added to HA, it is considered that HA is produced by decomposition of a high-boiling compound having a complex structure due to high-order HA quantification and cyclization. For example, in the case of a zeolite having a three-dimensional pore and a large space inside such as X-type, Y-type, or beta-type zeolite, higher-order multimerization and cyclization of HA occurs inside the pore, As a result, it is considered that acetoin decomposed from a high boiling point compound derived from HA is generated.

Specific examples of zeolite include ferrierite, mordenite, and ZSM-5.
Note that zeolite such as mordenite having a structure in which one-dimensional pores of 10 to 12 members are connected by small eight-membered pores is also included in the “zeolite having a linear pore structure”.

As the zeolite, an 8- to 12-membered zeolite having a pore diameter close to the molecular size of HA is preferable, and a 10- to 12-membered zeolite is particularly preferable.
Zeolite has a skeleton composed of SiO ₂ and Al ₂ O ₃ and is usually used as a proton-type solid acid catalyst. In the basic zeolite (3), the proton part is ionized with alkali metal or alkaline earth metal. It has been exchanged. As the basic zeolite (3), the alkali metal hydroxide used in the hydrothermal synthesis method, which is a general zeolite synthesis method, can be used as it is at the ion exchange site.

  A commercial product may be used as such a zeolite. Specific examples of commercially available products include Tosoh Na-type mordenite HSZ-642NAA and HSZ-640NAA, Tosoh Na-type and K-type ferrierite HSZ-770NAA, HSZ-720KOA and the like. Many of these are of the Na type.

Na in the Na-type zeolite may be ion-exchanged with another alkali metal or alkaline earth metal.
Ion exchange can be performed, for example, by the following method. A 0.5 mol / l aqueous solution of the target alkali metal, alkaline earth metal chloride or nitrate is prepared, and Na type zeolite is immersed in this, and it is placed on a 85-90 ° C. water bath for 20 hours (about 1 hour). Ion exchange is carried out by holding. Thereafter, the product is sufficiently washed with deionized water and dried at 120 ° C. for 10 hours to obtain a catalyst ion-exchanged with the desired alkali metal or alkaline earth metal.

<Conversion process>
In the method for reducing HA according to the present invention, the conversion step of bringing hydroxyacetone into a high boiling point compound by bringing the untreated crude phenol into contact with the solid base catalyst (A) is carried out.

  Examples of the reaction apparatus for carrying out this conversion step include a batch type reaction apparatus, a fixed bed continuous reaction apparatus, a fluidized bed continuous reaction and a moving bed continuous reaction apparatus. In view of simple equipment, it is desirable to use a fixed bed continuous reaction apparatus.

The temperature at the time of carrying out the conversion step is usually 100 to 300 ° C, preferably 130 to 250 ° C.
The pressure at the time of implementing the said conversion process is 0.1-30 Mpa normally, Preferably it is 0.5-10 Mpa.
The time for performing the conversion step is usually 1 to 20 hours when the conversion is a batch reaction.

Also, if the conversion is a continuous reaction, the feed rate of the untreated crude phenol per unit volume of the solid base catalyst (A) (LHSV) is desirably at 0.5 hr ^-1 or more 20 hr ^-1 or less More preferably, it is ¹ hr ⁻¹ or more and 10 hr ⁻¹ or less. When a continuous reaction apparatus is used in the present invention, the reactor used may be a single reactor or a plurality of reactors. Particularly in the case of a plurality of reactors, the reaction conditions can be controlled more precisely by installing the reactors in series.

  In the crude phenol subjected to the conversion step, the concentration of hydroxyacetone is usually 0.01% by weight or more and 1.0% by weight or less, preferably 0.7% by weight or less, more preferably 0.5% by weight. The lower limit thereof may be 0.05% by weight or 0.1% by weight.

  Increase amount of acetoin in the conversion step (ie, (concentration of acetoin in crude phenol after contact with solid base catalyst (A) (weight basis))-(crude phenol before contact with solid base catalyst (A)) The concentration of acetoin in (untreated crude phenol) (weight basis)) is preferably 20 ppm or less, more preferably 2 ppm or less. These can be analyzed by gas chromatography, and as the conditions, for example, the conditions employed in the examples described later or equivalent conditions can be employed.

[Production method of high-purity phenol]
The method for producing crude phenol with a small amount of hydroxyacetone according to the present invention includes a step of reducing HA from a crude phenol containing HA by the method for reducing HA according to the present invention.

  In addition, the high purity phenol production method according to the present invention includes a step of reducing HA from a crude phenol containing HA by the HA reduction method according to the present invention, and a high-boiling compound derived from HA in this step is removed by distillation. And a step of performing. Since this high boiling point compound has a large difference in melting point from phenol, it can be easily separated and removed from phenol by distillation. Distillation can be carried out based on conventional methods.

  The amount of HA and acetoin in the crude phenol subjected to the HA reduction method according to the present invention is small, and impurities other than HA and acetoin contained in the crude phenol can be easily removed by distillation or the like as described above. .

  The term “high purity” is used to mean that there are fewer impurities than the crude phenol, and the impurity concentration (weight basis) in the high purity phenol is, for example, 500 ppm or less. The concentration of acetoin in the crude phenol and the concentration of acetoin in the high-purity phenol subjected to the HA reduction method according to the present invention are preferably 40 ppm or less, more preferably 20 ppm or less, and further preferably 2 ppm or less. These can be analyzed by gas chromatography, and as the conditions, for example, the conditions employed in the examples described later or equivalent conditions can be employed.

According to the method for producing high-purity phenol according to the present invention, high-purity phenol with less acetoin that greatly deteriorates the quality of HA and phenol can be produced.
Furthermore, according to the method for producing high-purity phenol according to the present invention, while the phenols and α-methylstyrene, which are useful components, are reacted with impurities, or are prevented from reacting with each other or independently, respectively. High-purity phenol can be produced. For this reason, it becomes possible to isolate | separate and remove alpha-methylstyrene which is a useful component from phenol in the state which can be utilized industrially, and to manufacture high purity phenol.

  The method for producing bisphenols according to the present invention includes a step of carrying out the method for producing high-purity phenol according to the present invention and a step of producing bisphenols using the high-purity phenol as a raw material. .

The method for producing bisphenols according to the present invention can be carried out based on a conventionally known method for producing bisphenols, except that the raw material phenol is produced by the method for producing high-purity phenol according to the present invention. it can.
Examples of the bisphenols include 2,2′-bis (4-hydroxyphenyl) propane and bis (4-hydroxyphenyl) methane.

  Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited thereto. The conversion rate of the carbonyl compound and the amount of acetoin produced were calculated from the analytical values obtained by gas chromatography.

  The GC analysis conditions are as follows. GC-2014 manufactured by Shimadzu Corporation was used, FID was used for the detector, DB-WAX (60 m, inner diameter 0.25 m, film thickness 0.25 μm) was used for the GC column, and He was used for the carrier gas. The injection temperature and detection temperature were set to 250 ° C., the inlet pressure was set to 157 kPa, and the linear velocity was set to 23 cm / second. The temperature was raised from 50 ° C., raised to 240 ° C. at a rate of 5 ° C./min, and kept at 240 ° C. for 100 minutes, and then the measurement was carried out.

The conversion rate of the carbonyl compound means the molar ratio (%) of the decrease amount due to the reaction of the carbonyl compound with respect to the amount of the carbonyl compound before the reaction.
The amount of acetoin produced means the acetoin concentration (weight basis, ppm) in the reaction solution after the reaction.

[Example 1]
Using a fixed bed reactor equipped with a feed pump, a high-pressure nitrogen mass flow, an electric furnace, a reactor filled with a catalyst, and a back pressure valve, a pressurized liquid phase flow reaction was performed by downflow. A reactor made of SUS316 having an inner diameter of 1 cm was charged with 2.0 g of Y ₂ O ₃ compression-molded at 20 MPa as a solid base catalyst and classified into 250 to 500 μm. After pressurizing the inside of the reactor to 0.5 MPa with nitrogen gas, nitrogen was introduced into the reactor at 10 ml / min, hydroxyacetone (HA) 1800 ppm, mesityl oxide (MO) 500 ppm, α-phenylpropionaldehyde (α -PPA) 1300 ppm, α-methylstyrene (α-MS) 500 ppm, 2-phenyl-2-propanol (Cnol) 6000 ppm, acetophenone (Anone) 2.41% by weight and other impurities, and phenol 91.8% by weight The crude phenol was fed at 5.0 g / h and contacted with a solid base catalyst at 250 ° C. When the reaction solution 20 hours after the start of the supply of the crude phenol was analyzed by gas chromatography, acetoin was not detected (GC detection limit of 2 ppm), the HA conversion was 99.5%, and the MO conversion was 31.9. %, Α-PPA conversion rate was 97.5%, and Anone conversion rate was 2.0%. Further, there was no difference in the phenol concentration before and after the reaction (PH concentration) within the range of analysis accuracy of gas chromatography. The results are shown in Table 1.

[Example 2]
(Preparation of Na / SiO ₂ )
As a solid base catalyst, a Na / SiO ₂ catalyst was prepared by the pore-filling method with reference to Journal of Catalysis, 204, 358, 2001. A solution obtained by dissolving 4.69 g of sodium acetate in 23.9 g of distilled water was dropped with a dropper onto 26.30 g of silica gel (Fuji Silysia Caractect Q-30, pore volume 1.0 ml / g) and impregnated as a whole. . This silica gel is put into a baking furnace, dried at 100 ° C. for 2 hours, then heated to 500 ° C. over 1 hour, and baked for 5 hours, thereby supporting sodium oxide supported by 4.5% by weight as Na. 29.09 g of silica gel (Na / SiO ₂ ) was obtained.

(Reaction evaluation)
The same operation as in Example 1 was performed except that Na / SiO ₂ prepared as described above was used in place of Y ₂ O ₃ . When the reaction solution 20 hours after the start of the supply of the crude phenol was analyzed by gas chromatography, acetoin was not detected and the HA conversion was 79.8%. The results are shown in Table 1.

Example 3
The same operation as in Example 1 was performed except that MgO was used instead of Y ₂ O ₃ . When the reaction solution 20 hours after the start of the supply of the crude phenol was analyzed by gas chromatography, acetoin was not detected and the HA conversion was 79.0%. The results are shown in Table 1.

Example 4
The same operation as in Example 1 was carried out except that Tosoh Na-exchanged mordenite type zeolite (HSZ-640NAA) was used instead of Y ₂ O ₃ . When the reaction solution 20 hours after the start of the supply of the crude phenol was analyzed by gas chromatography, acetoin was not detected and the HA conversion rate was 52.9%. The results are shown in Table 1.

Example 5
The same operation as in Example 1 was performed except that ferrilite type zeolite (HSZ-720KOA) exchanged with Na and K made by Tosoh was used instead of Y ₂ O ₃ . When the reaction solution 20 hours after the start of the supply of the crude phenol was analyzed by gas chromatography, acetoin was not detected and the HA conversion was 45.6%. The results are shown in Table 1.

[Comparative Example 1]
Kyowa Chemical Industries hydrotalcite (KW-500SH) was calcined at 550 ° C. for 5 hours, compression molded at 20 MPa, and then classified into 250 to 500 μm, except that Y ₂ O ₃ was used instead of Y ₂ O _3. Was performed. When the reaction solution 20 hours after the start of the supply of the crude phenol was analyzed by gas chromatography, it contained 60 ppm of acetoin and the HA conversion rate was 90.1%. The results are shown in Table 1.

[Comparative Example 2]
The same operation as in Example 1 was carried out except that Naso-exchanged Y-type zeolite (HSZ-320NAA) manufactured by Tosoh was compression molded at 20 MPa and classified into 250 to 500 μm instead of Y ₂ O ₃ . When the reaction solution 20 hours after the start of the supply of the crude phenol was analyzed by gas chromatography, it contained 50 ppm of acetoin and the HA conversion rate was 50.1%. The results are shown in Table 1.

Claims (12)

  A solid containing at least one of a crude phenol containing hydroxyacetone, a weakly basic solid base catalyst (i) containing a metal oxide, and a solid basic catalyst (ii) containing a basic zeolite having a linear pore structure A method for reducing hydroxyacetone in crude phenol, comprising a conversion step of contacting the base catalyst (A) to convert the hydroxyacetone to a high-boiling compound.   The solid base catalyst (A) includes the solid base catalyst (i), and the solid base catalyst (i) is an oxide (1) of a group IIA or IIIB metal element, or a group IA or IIA metal element. The method for reducing hydroxyacetone in crude phenol according to claim 1, wherein the oxide is supported on silica gel (2).   The solid base catalyst (A) contains the solid base catalyst (ii), the solid base catalyst (ii) has a linear pore structure and contains a metal element of Group IA or IIA It is a zeolite (3), The method of reducing the hydroxyacetone in the crude phenol of Claim 1 characterized by the above-mentioned.   The solid base catalyst (A) includes the oxide (1) of the group IIA or IIIB metal element, and the oxide (1) of the group IIA or group IIIB metal element is selected from yttrium oxide and magnesium oxide. The method for reducing hydroxyacetone in crude phenol according to claim 2, which is at least one kind.   The method for reducing hydroxyacetone in crude phenol according to claim 3, wherein the zeolite used for the basic zeolite (3) is an 8- to 12-membered ring zeolite.   The method for reducing hydroxyacetone in crude phenol according to claim 3, wherein the zeolite used for the basic zeolite (3) is at least one selected from ferrierite, mordenite and ZSM-5.   The method for reducing hydroxyacetone in crude phenol according to any one of claims 1 to 6, wherein the conversion step is performed under conditions of 100 to 300 ° C and atmospheric pressure to 3 MPa.   The method for reducing hydroxyacetone in the crude phenol according to any one of claims 1 to 7, wherein an increase in acetoin concentration (weight basis) in the crude phenol in the conversion step is 20 ppm or less.   The manufacturing method of the crude phenol with few hydroxy acetone characterized by including the process of reducing hydroxy acetone from the crude phenol containing hydroxy acetone by the method of any one of Claims 1-8.   A high purity comprising a step of reducing hydroxyacetone from a crude phenol containing hydroxyacetone by a method according to any one of claims 1 to 8, and a step of removing the high boiling point compound by distillation. A method for producing phenol.   The manufacturing method of bisphenol characterized by including the process of manufacturing high purity phenol by the manufacturing method of Claim 10, and the process of manufacturing bisphenol using the said high purity phenol as a raw material. Oxidation of alkylbenzene to alkylaryl hydroperoxide a.
A step b of concentrating the alkylbenzene oxidation reaction product obtained in the step a to obtain a concentrated liquid;
A step c in which an alkylaryl hydroperoxide contained in the concentrate is cleaved with phenol and a ketone in the presence of an acid catalyst to obtain an acid cleavage product;
A process for producing high-purity phenol by a cumene method, comprising a step d of neutralizing the acid cleavage product, and a step e of distilling the neutralized acid cleavage product into phenol and impurities,
The step (e) removes at least a part of a light fraction from the neutralized acid cleavage product to prepare a crude phenol containing hydroxyacetone, from the crude phenol containing hydroxyacetone. A method for producing high-purity phenol by the cumene method, comprising a step of reducing hydroxyacetone by the method according to any one of the above and a step of removing the high-boiling compounds by distillation.