JPH0262842A - Production of phorone - Google Patents

Abstract

PURPOSE:To obtain phorone in high yield by subjecting acetone to aldol condensation in the presence of an alkali catalyst to give mesityl oxide, dehydrating a residual oil an acetone trimer in an acid catalyst such as phosphoric acid base under heating and distilling. CONSTITUTION:Acetone is subjected to aldol condensation in the presence of an alkali catalyst, mesityl oxide is distilled and separated, a residual oil containing acetone trimer is dehydrated in the presence of 1-10wt.% acid catalyst (preferably phosphoric acid base) under reduced pressure at 50-130 deg.C, preferably 90-120 deg.C so that other acetone trimers are converted into phorone and distilled to give phorone shown by the formula. A reactor is equipped with Dean Stark separator or oil-water separator and formed water is taken out from the reaction system so that equilibrium relationship is transferred to a formation system to give phorone. The acetone trimers are economically not abandoned. Phorone is useful as a raw material for agricultural chemicals, coating compound for ship bottom, antistatic agent, polyamide resin, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for producing holon, and in particular, the present invention relates to a method for producing holon, and in particular, a method for producing holon using acetone as a raw material and distillation separation in a methyl isobutyl ketone production plant via aldol condensation using an alkaline catalyst. The present invention relates to a method for producing holon from acetone trimer present in residual oil.

[Prior art]

Holon is produced by saturating acetone with hydrogen chloride or by passing isopropyl alcohol over dehydrated zinc sulfate.

Holon is used as a raw material for agricultural chemicals, ship bottom paints, antistatic agents, polyamide resins, etc., and is useful as a raw material for resin additives.

By the way, in industrial plants, tantyl oxide is produced from acetone, and methyl isobutyl ketone is produced from tantyl oxide. This tantyl oxide is a dimer of acetone, but acetone trimers such as holone are produced as by-products in the residue during distillation, separation and purification. These acetone trimers contain holon (PHO)
In addition to 2,6-cyhydroxy-2,6-cymethyl-4-
Heptanone (DDH), 6-hydroxy-2,6-dimethyl-2-hepten-4-one (S-PHOL 2,2
, 6,6-titramethyltetrahydropyran-4-one (TTPK), etc., and the following equilibrium relationship exists.

(A) (DAA) (MO) (CH,) 2CCH,CC)(IC(CH3)!(D
DI() (CH,) 2C=CIICCIl=C(C11,).

(TTPK) (PHO) OCH.

(CH+) gc=cHccHzc=cHz(PHO-
iso) [Problems to be solved by the invention] However, when purifying holon from such a residue by distillation, the yield of holon is poor due to the presence of a large amount of acetone trimer other than holon; Acetone trimer is discarded during holon purification and is uneconomical. In addition, in the residual oil, water, tantyl oxide, diacetone alcohol, holone isomer,
．． 2゜6.6-Titramethyltetrahydrobilane-4-
on, holon, 6-hydroxy-2,6-cymethyl-2
- Hepten-4-one is mixed.

For this reason, the effective holons and holon isomers are defined as 2.26.6
The present invention was developed in view of the above circumstances, in which there is a problem in that simple distillation separation is not possible from titramethyltetrahydropyran-4-one. The purpose of the present invention is to provide a method for producing holons that can obtain holons in high yield without discarding the body.

[Means for solving problems]

In order to achieve the above object, the present invention subjects acetone to an aldol condensation reaction using an alkaline catalyst, and then distills and separates the residual oil containing acetone trimer as a residue of tantyl oxide, into an acid catalyst. It is characterized by separating and purifying holons by heating and dehydrating them and distilling them.

Further, it is preferable to use a phosphoric acid-based dehydration catalyst as the acid catalyst.

The reaction conditions are characterized by separating the water generated when the residual oil is heated and dehydrated in an acid catalyst out of the reaction system, and by bubbling an inert gas into the reaction liquid of the residual oil. Separation of produced water to the outside of the reaction system may be promoted. Alternatively, an inert gas may be passed above the residual oil reaction solution to promote separation of the produced water out of the reaction system.

When residual oil is heated and dehydrated with an acid catalyst and then stored for 5 hours or more, the temperature is kept at 30°C or lower.

When the residual oil is heated and dehydrated with an acid catalyst and then the holon is separated by distillation, the acid catalyst is separated and removed, and an aqueous alkaline solution is added to separate the organic acid in the reaction residual oil, followed by distillation.

[Effect]

According to the method for producing holon according to the present invention, by heating in an acid catalyst, 2,6-cyhydroxy-2,6-dimethyl-4-heptanone, 2,2
, 6,6-titramethyltetrahydropyran-4-one and other acetone trimers become holons through dehydration reaction. In particular, 2゜6-cyhydroxy-2,6-cymethyl-4
-heptanone, 6-hydroxy-2,6-cymethyl-2
Tertiary alcohols such as -hebuten-4-one easily convert to holon. Moreover, sulfuric acid, nitric acid, hydrochloric acid, and phosphoric acid are used as acid catalysts. Although acid catalysts have adverse effects such as decomposition of the generated holons, phosphoric acid catalysts have less of this decomposition and are suitable for use in the present invention.

Furthermore, under the reaction conditions, if the pressure of the reaction system is reduced, the heating reflux temperature of tantyl oxide, etc. generated in the reaction system in the residual oil can be lowered to 130° C. or lower. If the heating reflux temperature is high, decomposition of holon will be promoted, which is not preferable.

If water is separated out of the reaction system under the reaction conditions, the equilibrium relationship of each acetone trimer in the residual oil will be disrupted;
, 6.6-titramethyltetrahydrobilan-4-one and other alcohols other than tertiary alcohols are also easily converted to holon.

Furthermore, bubbling of an inert gas in the reaction residue oil efficiently removes moisture generated in the reaction solution, and even if the inert gas is passed above the reaction residue oil, the removal of moisture is promoted.

In the distillation purification of holon from reaction residue oil, by removing the acid catalyst from the reaction system in advance, corrosion of the reactor during the reaction is prevented, and organic acid impurities in the residue oil are easily removed using an alkaline solution. can. In addition, when storing the reaction solution after the reaction of the residual oil, if the temperature is kept below 30°C, 2°2.6.6-titramethyltetrahydropyran-4-one may be regenerated by hydration. Prevented.

[Preferred embodiment of the invention]

Hereinafter, preferred embodiments of the present invention will be explained in detail.

Residue Dish The residual oil used in the present invention is a residue from a known method for producing tantyl oxide, and is a residual oil obtained by distilling and separating acetone, diacetone alcohol, and tantyl oxide.

The residual oil contains a small amount of diacetone alcohol, tantyl oxide, as well as holon, holon isomer, 2.2.6.6
-Titramethyltetrahydrobilan-4-one, 2,6
-cyhydroxy-2,6-cymethyl-4-heptanone,
6-hydroxy-26-cymethyl-2-hebutene-4-
Acetone trimers exist in an equilibrium relationship.

Acid catalysts used in the present invention include mineral acids such as sulfuric acid, nitric acid, hydrochloric acid, and phosphoric acid, strongly acidic ion exchange resins such as Amberlyst 15 (manufactured by Rohm and Haas), and activated clay. , phosphoric acid supported on silica or silica titania, etc. In particular, phosphoric acid catalysts are effective in accelerating the dehydration reaction, and there is less re-decomposition of generated holons than other acid catalysts.

The acid catalyst is used in the reaction system in an amount of 0.1 to 20% by weight, preferably 1 to LOf[t%. Too little acid catalyst will reduce the reaction rate, and too much will affect the holons produced.

Direct sowing ■ Anniwajoka 2.2,6.6-titramethyltetrahydropyran-4
-one, 2,6-cyhydroxy-2,6-cymethyl-4
Acetone trimers such as -heptanone and 6-hydroxy-2,6-dimethyl-2-hebuten-4-one are subjected to a heating reaction in order to produce holons through a dehydration reaction.

The heating temperature is at least 1 to reflux water and 2+i1 bodies such as diacetone alcohol and tantyl oxide.
The temperature is set to 30°C or higher. However, at a temperature of 130° C. or higher, the decomposition of the formed holons becomes more intense, so it is preferable to lower the reflux temperature by reducing the pressure. Therefore, by adjusting the reaction system under reduced pressure, the reaction reflux temperature can be adjusted from 50 to 130°C.
It is preferably set in the range of 90 to 120°C rather than 1°C.

In order to remove water from the reaction system, the reactor is equipped with a Dean-Stark separator and an oil-water separator. The water produced by the reaction is refluxed under the reduced pressure and temperature conditions described above, and is discharged and removed from the reaction system using these separators. As a result, the equilibrium relationship of the acetone trimer shifts to a holon production system, and holons can be obtained in high yield.

In addition, in the acetone trimer, 2,6-
Cyhydroxy-2,6-cymethyl-4-heptanone, 6
-Hydroxy-2,6-dimethyl-2-hebutene-4-
On etc. are easily converted to holons by intramolecular dehydration.

However, 2,2,6.6- which has a cyclic ether type structure
Since titramethyltetrahydrobilan-4-one is not easily converted, it is preferable to remove water from the reaction system based on the method described above.

Furthermore, during the reaction, an inert gas is passed through and bubbled through the reaction solution of the residual oil, and in some cases, an inert gas is passed above the reaction solution.

Since the inert gas efficiently removes trace amounts of water contained in the reaction liquid out of the reaction system, most of the water in the reaction liquid is removed. Therefore, 2,2,6,6-titramethyltetrahydrobyran-4-one is almost transferred to holon, and the residual oil contains 2,2,6,6-titramethyltetrahydropyran-4-one.
-on no longer exists. Therefore, during purification of holon, contamination of 2,2,6,6-titramethyltetrahydrobilan-4-one, which has a similar boiling point, is prevented. like this,
The flow of inert gas is particularly effective in the latter stages of the reaction when produced water decreases.

The end point of the dehydration reaction is defined as the point at which 2,2,6,6-titramethyltetrahydropyran-4-one is no longer detected by gas chromatography.

Therefore, the reaction time varies depending on the concentration of the acid catalyst, the reaction temperature, and the flow rate of the inert gas, and is usually 5 to 20 hours.

-+1 of the holon of '' The holon in the reaction product is purified by distillation, and when distilled in the presence of an acid catalyst, it is carried out at a temperature of 130°C or higher. For this reason, decomposition of holons is likely to occur, and there is a bottom that corrodes the reactor. Therefore, it is preferable to distill holon after removing the acid catalyst.

Although the method for separating the acid catalyst is not particularly specified, it can usually be separated by a water washing method. In particular, in the case of phosphoric acid, the amount of water used in the first washing is set so that the phosphoric acid concentration of the phosphoric acid wastewater obtained by washing with water is about 20 to 50% by weight. Second
It is preferable to completely separate the phosphoric acid in the multiple washings. The reaction washing wastewater may be discarded, but may be used again for the dehydration reaction.

Furthermore, the reaction residue oil contains a small amount of organic acid, which is mixed in when the holon is purified by distillation of the reaction residue oil. Depending on the use of Holon, this organic acid can have an adverse effect. For example, when synthesizing a light stabilizer for polyolefins, holon is used as a starting material and the intermediate is triacetyl[
This compound is derived from the hydrogenation reaction of 2,2,6,6-titramethyltetrahydropiperidin-4-one synthesized from holone and ammonia. In this case, a Raney nickel catalyst is usually used for hydrogenation, but if an organic acid is present in the phoron, this acts as catalyst poison and inhibits the reaction. Therefore, the reaction residue oil is 2. Preferably, organic acids are removed by treatment with a sodium hydroxide solution before distillation purification. Organic acid removal treatment is 0.
Sodium hydroxide is used in the range of 0.05 to 2% by weight, more preferably 0.1 to 0.5% by weight.

In addition, in the production of holon according to the present invention, the acid catalyst is separated from the reaction residual oil, but if the residual oil is stocked before this separation, 2.2
, 6,6-titramethyltetrahydropyran-4-one increases as the temperature increases (approximately 60°C). Therefore, when storing for 5 hours or more, it is preferable to store at 30°C or lower.

〔Example〕

Examples of the present invention will be shown below.

(Example 1) A reactor is charged with 95% by weight of residual oil from the production of methyl isobutyl ketone and 5% by weight of phosphoric acid as an acid catalyst.

The pressure inside the reactor is reduced and the reaction is carried out at a temperature of 110° C., and nitrogen is bubbled into the reaction residue oil as an inert gas.

Additionally, a separator is attached to the reactor to separate the produced water.

The end point of the reaction was defined as the point at which 2,2,6,6-titramethyltetrahydrobylan-4-one could not be detected by gas chromatography.

After the acid catalyst was removed from the reaction residue oil, 95% by weight of 0.5% by weight sodium hydroxide solution was added, and the oil layer after extracting and separating the organic acid was purified by distillation.

As a result, the yield of holon was 165%.

(Example 2) A reactor is charged with 85% by weight of residual oil from the production of methyl isobutyl ketone and 15% by weight of phosphoric acid as an acid catalyst.

The pressure inside the reactor is reduced and the reaction is carried out at a temperature of 90° C., and nitrogen is bubbled as an inert gas into the reaction residue oil.

Additionally, a separator is attached to the reactor to separate the produced water.

The end point of the reaction was defined as the point at which 2,2,6,6-titramethyltetrahydrobylan-4-one could not be detected by gas chromatography.

After the acid catalyst was removed from the reaction residue oil, 340% by weight of 0.1% by weight sodium hydroxide solution was added, and the oil layer after extracting and separating the organic acid was purified by distillation. As a result, the yield of holon was 154%.

(Example 3) The reaction was carried out in the same manner as in Example 1, except that nitrogen was not bubbled as an inert gas into the reaction residue oil.

As a result, 2.2.6.6-titramethyltetrahydropyran-4-one did not decrease below 0.3% by weight.

(Example 4) A reactor is charged with 99% by weight of residual oil from the production of methyl isobutyl ketone and 1% by weight of sulfuric acid as an acid catalyst. The other operations were the same as in Example 2. As a result, the yield of holon was 11
It was 0%.

(Example 5) The same procedure as in Example 2 was carried out except that 5% by weight of Amberlyst 15 (manufactured by Rohm and Haas) was used as the acid catalyst. As a result, the yield of holon was 105%.

(Example 6) A reactor was charged with 98% by weight of the residual oil from the production of methyl isobutyl ketone, and 2% by weight of R-NH, C)I2PO3H, type resin as an acid catalyst.

The reaction was carried out for 10 hours while reducing the pressure in the reactor, bubbling nitrogen, and separating produced water. As a result, 2,2.
The reaction rate of 6.6-titramethyltetrahydrobilan-4-one was 45%.

(Example 7) The dehydration reaction product obtained by the same operation as in Example 1 was maintained at temperatures of 30° C. and 60° C. without separating the acid catalyst. Sampling was performed at predetermined time intervals, and the concentration of 2.2,6.6-titramethyltetrahydrobilan-4-one (TTPK) was measured by gas chromatography. As a result, changes as shown in Table 1 were observed.

Table 1 (Comparative Example 1) The residual oil from the production of methyl isobutyl ketone was purified by direct distillation. As a result, the yield of holon was 85%.

〔Effect of the invention〕

As explained above, according to the method for producing holon according to the present invention, since the residual oil is heated and dehydrated with an acid catalyst, 2, 2,
6. Acetone trimers such as 6-titramethyltetrahydrobilan-4-one are produced as holons, and holons can be obtained in high yield without discarding acetone trimers other than holone from the residual oil during tantyl oxide production. You can get it at a high rate.

Patent applicant: Mitsui Petrochemical Industries, Ltd./゛7

Claims (1)

[Scope of Claims] (1) A residual oil containing acetone trimer as a residue of tantyl oxide obtained by subjecting acetone to an aldol condensation reaction with an alkaline catalyst and distilling it,
A method for producing holon, which comprises separating and purifying holon by heating and dehydrating it in an acid catalyst and distilling it. (2) Claim 1, wherein the acid catalyst is a phosphoric acid catalyst.
The method for producing holons described in Section 1. (3) The heating dehydration reaction is carried out at a temperature of 50 to 13°C under reduced pressure.
3. The method for producing a holon according to claim 1 or 2, wherein the method is carried out at a temperature of 0°C. (4) Claim 3, characterized in that water generated when the residual oil is heated and dehydrated in an acid catalyst is separated outside the reaction system.
The method for producing holons described in Section 1.