JPH03184928A - Production of saturated aliphatic or alicyclic dihydric alcohol - Google Patents

Abstract

PURPOSE:To readily obtain the subject substance by carrying out catalytic hydrogenolysis of a saturated aliphatic or alicyclic bifunctional carboxylic acid ester or hydroxycarboxylic acid ester in the presence of a monohydric alcohol. CONSTITUTION:An ester derived from a saturated aliphatic or alicyclic bifunctional carboxylic acid or hydroxycarboxylic acid with a monohydric alcohol derived from a >=6C alkane is subjected to catalytic hydrogenolysis in the presence of a <=4C monohydric alcohol at <=230 deg.C to afford the subject substance. A copper chromium oxide-based catalyst containing Ba or Mn is preferred as the catalyst for the hydrogenolysis. The temperature is slowly increased while flowing an inert gas at 1-5% hydrogen concentration and the gas flow rate and hydrogen concentration are regulated so that the catalyst temperature may be 130-140 deg.C or above but may nor exceed 170-180 deg.C. The hydrogen concentration is finally regulated to 100% to carry out the treatment at 200 deg.C for several hr. The subject substance is useful as a raw material for plasticizers, polyesters, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a method for producing saturated aliphatic or alicyclic dihydric alcohols. More specifically, saturated aliphatic or alicyclic 2
The present invention relates to a method for producing a saturated aliphatic or alicyclic dihydric alcohol by catalytic hydrogenolysis of a hydroxycarboxylic acid ester or a saturated aliphatic or alicyclic hydroxycarboxylic acid ester.

Saturated aliphatic dihydric alcohols and alicyclic dihydric alcohols are useful substances as raw materials for plasticizers, polyesters, polyurethanes, and the like.

(Prior Art) It is widely known that alcohols are produced by catalytic hydrogenolysis of various esters.

For example, H. Adkins, “Organic Re
action”, Vol■+p, 1+ John Wi
lly & 5ons+New York (1954)
describes data on hydrogenolysis of various aliphatic carboxylic acid esters using a Cu-Cr oxide catalyst.

Also, JP-A-50-160211, JP-A-50-160
In No. 212, etc., 16-hexanediol is obtained by hydrogenolyzing adipic acid ester and ε-oxycaproic acid ester obtained by esterifying carboxylic acids and oxyacids from a reaction solution obtained by liquid-phase oxidation of cyclohexane. A method of manufacturing is described.

(Problems to be Solved by the Invention) The inventors previously disclosed in Japanese Patent Application No. 63-280269 that monohydric alcohols derived from alkanes having 6 or more carbon atoms, particularly branched alcohols having 6 or more carbon atoms, By catalytic hydrogenolysis of an esterified product of a monohydric alcohol derived from an alkane and a saturated aliphatic or alicyclic polyhydric carboxylic acid, or a saturated aliphatic or alicyclic hydroxycarboxylic acid, a saturated aliphatic It has also been found that alicyclic polyhydric alcohols can be obtained in extremely high yields.

The inventors conducted further studies on the industrial production of saturated aliphatic or alicyclic dihydric alcohols, and as a result, the following problems became clear.

(1) When the reaction temperature increases in a catalytic hydrogenolysis reaction, a small amount of hydroxyether compound is produced as a by-product.

(2) It is extremely difficult to separate this compound from the target dihydric alcohol, making it impossible to obtain a highly pure dihydric alcohol.

(3) Since the catalytic hydrogenolysis reaction is an exothermic reaction, if an attempt is made to increase the conversion rate in an adiabatic reactor, the temperature will rise near the outlet of the catalyst layer, and the hydroxyether compound of (1) will be produced as a by-product. Difficult to avoid.

(Means for Solving the Problems) As a result of intensive studies to solve the above problems, the present inventor found that if a monohydric alcohol having 4 or less carbon atoms is used as a solvent in the present catalytic hydrogenolysis reaction, It was discovered that the production of by-products was significantly suppressed and the reaction rate (ester conversion rate) was improved, leading to the present invention.

That is, the present invention provides an ester of a saturated aliphatic or alicyclic dihydric carboxylic acid, or a saturated aliphatic or alicyclic hydroxycarboxylic acid, and a monohydric alcohol derived from an alkane having 6 or more carbon atoms. is a method for producing a saturated aliphatic or alicyclic dihydric alcohol, which is characterized by carrying out catalytic hydrogenolysis in the presence of a monohydric alcohol having 4 or less carbon atoms.

The esters to be hydrogenolyzed in the method of the present invention are produced by the esterification reaction of saturated aliphatic or alicyclic dicarboxylic acids, or their anhydrides, hydroxycarboxylic acids, lactones, and alcohols. be done. Note that the saturated aliphatic or alicyclic dicarboxylic acid used in the esterification reaction with alcohol includes not only saturated aliphatic or alicyclic dicarboxylic acids but also partially esterified compounds, In the case of saturated aliphatic dicarboxylic acids, general 2C,,H2n+2-+1+b) (COOH)a (G
OOR)b, general formula C in the case of alicyclic divalent carboxylic acid
711□□14b.

(COOI+), (COOR)b (where R is the alcohol residue, a and b are 0 or a positive integer where a+b=2, and n is O or a positive integer where n+a+b≧3).

Examples of the saturated aliphatic dicarboxylic acids include malonic acid, succinic acid, methylmalonic acid, glutaric acid, methylsuccinic acid,
Ethylmalonic acid, dimethylmalonic acid, adipic acid, methylglutaric acid, ethylsuccinic acid, dimethylsuccinic acid, propylmalonic acid, ethylbutylmalonic acid, pimelic acid,
Methyladipic acid, ethylglutaric acid, dimethylglutaric acid, propylsuccinic acid, ethylmethylsuccinic acid, trimethylsuccinic acid, butylmalonic acid, propylmethylmalonic acid, diethylmalonic acid, schelic acid, methylpimelic acid, ethyladipic acid, dimethyladipine Acid, propylglutaric acid, ethylmethylglutaric acid, trimethylglutaric acid, butylsuccinic acid, propylmethylsuccinic acid, diethylsuccinic acid, ethyldimethylsuccinic acid, tetramethylsuccinic acid, pentylmalonic acid, butylmethylmalonic acid, ethylpropylmalonic acid , azelaic acid, methyladipic acid, ethylpimelic acid, dimethylpimelic acid, propyladipic acid, ethylmethyladipic acid, trimethyladipic acid, butylglutaric acid, propylmethylglutaric acid, diethylglutaric acid, ethyldimethylglutaric acid, tetramethylglutaric acid Acid, pentyl succinic acid, butyl methyl succinic acid, ethyl propyl succinic acid, propyl dimethyl succinic acid, diethyl methyl succinic acid, ethyl trimethyl succinic acid, hexyl malonic acid, methyl pentyl malonic acid, ethyl butyl malonic acid, dipropyl malonic acid,
Sebacic acid, methyladipic acid, ethylsperinic acid, dimethylspernic acid, probylpimelic acid, ethylmethylpimelic acid, trinotylpimelic acid, butyladipic acid, propylmethyladipate, diethyladipic acid, ethylmethylpimelic acid, 1-ramethyladipic acid, pentylglutaric acid, butylmethylglutaric acid, ethylpropylglutaric acid, propyldimethylglutaric acid, diethylmethylglutaric acid, ethyltrimethylglutaric acid,
Pentamethylglutaric acid, hexylsuccinic acid, methylpentylsuccinic acid, ethylbutylsuccinic acid, dipropylsuccinic acid, butyldimethylsuccinic acid, ethylpropylglutaric acid, triedylsuccinic acid, propyltrimethylsuccinic acid, diethyldimethylsuccinic acid, heptylmalonic acid ,
Hexylmethylmalonic acid, ethylpentylmalonic acid, butylpropylmalonic acid, nonanedicarboxylic acid, decanedicarboxylic acid, undecanedicarboxylic acid, dodecanedicarboxylic acid, 1-lysocandicarboxylic acid, tetradecanedicarboxylic acid, pentadecanedicarboxylic acid, hexadecanedicarboxylic acid, Examples include heptadecanedicarboxylic acid, octadecanedicarboxylic acid, nonadecanedicarboxylic acid, and the like.

Examples of alicyclic dicarboxylic acids include cyclopropanedicarboxylic acid, methylcyclopropanedicarboxylic acid, dimethylcyclopropanedicarboxylic acid, ethylcyclopropanedicarboxylic acid, cyclobucunshicarboxylic acid, methylcyclobutanedicarboxylic acid, and 1-lymethylcyclobutanedicarboxylic acid. acid, propylcyclobutane dicarboxylic acid, cyclopencune dicarboxylic acid, cyclohexane dicarboxylic acid, bicyclohexyl dicarboxylic acid, decalin dicarboxylic acid, and the like.

In the present invention, in addition to esters of these saturated aliphatic dicarboxylic acids and alcohols, saturated aliphatic dicarboxylic acid anhydrides derived from these saturated aliphatic dicarboxylic acids by dehydration, saturated Hydroxycarboxylic acids in which a portion of the carboxy groups of aliphatic polyhydric carboxylic acids have been changed to one -C1120) group, and esterified products of lactones and alcohols derived from these hydroxycarboxylic acids by dehydration are used.

In addition, the alcohol residues of these esters are monohydric alcohols derived from alkanes with 6 or more carbon atoms, and monohydric alcohols derived from branched alkanes with 6 or more carbon atoms have particularly high yields. can get. 1
The alcohol can be primary, secondary, or tertiary alcohol, but -
Preference is given to using alcohols of the same class.

Such alcohols include 2,3-dimethyl 2-
Butanol, 3,3-dimethyl-1-butanol, 3.
3-dimethyl-2-butanol, 2-ethyl-1-butanol, 1-hexanol, 2-hexanol, 3-hexanol, 2-methyl-1-pentanol, 2-methyl-2-pentanol, 2-methyl- 3-pentanol, 3-methyl-1-pentanol, 3-methyl-2-pentanol, 3-methyl-3-pentanol, 4-methyl-1-pentanol, 4-methyl-2-pentanol,
2,2-dimethyl-3-pentanol, 2,3-dimethyl-3-pentanol, 2,4-dimethyl-3-pentanol, 2,4-dimethyl-2-pentanol, 4,4-
Dimethyl 2-pentanol, 3-ethyl-3-pentanol, 1-heptatool, 2-heptatool, 3-heptatool, 2-methyl-2-hexanol, 2-methyl-3-hexanol, 5-methyl- 2-hexanol,
4-methyl-3-heptatool, 6-methyl-2-heptatool, 1-octatool, 2-octatool, 3-
octatool, 2-propyl-1-pentanol, 2,
4.4~trimethyl-■-pentanol, 2-ethylhexanol, 2,6-dimethyl-4-heptatool, 1
-nonanol, 2-nonanol, 3,5.5-) riftyl-1-hexanol, monomethyloctatool, dimethylheptatool, ■-decanol, 2-decanol, 4-decanol, ■-undecanol, 1-dodecanol, 1-tridecanol and the like.

These alcohol residues may be the same as ester residues of saturated aliphatic dicarboxylic acids, or may be different from each other.

The esterification reaction between an alcohol and a saturated aliphatic dicarboxylic acid proceeds either in the presence or absence of a catalyst.

When a catalyst is used in the esterification reaction, any known catalyst may be used, such as p-toluenesulfonic acid, methanesulfonic acid, ethanesulfonic acid, ion exchange resins, heteropolyacids, acidic catalysts such as sulfuric acid and phosphoric acid, tin oxide, Insoluble suspension catalysts such as zinc oxide, antimony oxide, titanium oxide, silica-alumina composite oxide, tetraisopropyl titanate, tetradiyl titanate-1, tetra-2-
Titanium compounds such as conitylhexyl titanate and their polymers, tin oxalate, tin tetrabutyrate,
Although tin compounds such as tin tetrabutylene 1- are used, it is preferable to use a catalyst that does not contain halogen or sulfur elements in view of the influence on the hydrogenolysis catalyst.

The hydrocracking catalyst used in the present invention is a known hydrocracking catalyst, such as a catalyst containing iron, nickel, cobalt, copper, copper/chromium oxide, platinum, etc. as a main component, but especially barium or Higher yields can be obtained with copper/chromium oxide catalysts containing manganese. The catalyst may be in any form, such as powder or tablet, and the form most suitable for the form of use is used. This catalyst is usually activated by hydrogen treatment and used for the reaction. Generally, the conditions for this hydrogen treatment vary depending on the catalyst used, but for example, in the case of a copper/chromium oxide catalyst, the temperature is gradually raised while flowing an inert gas with a hydrogen concentration of 1 to 5χ. When the temperature reaches 130 to 140°C, hydrogen absorption begins, and the temperature of the catalyst rises rapidly due to an exothermic reaction. At this time, the catalyst temperature is 200℃1, preferably 170~180"C
Adjust the gas flow rate and hydrogen concentration so as not to exceed.

Once the exothermic reaction has finished, the hydrogen concentration is gradually increased until it reaches 1.
After processing at 200° C. for several hours as 00χ, the hydrogen treatment is completed.

This hydrocracking reaction can be carried out in a batch manner, but it is more preferable to carry out the reaction in a bath liquid format using a fixed bed catalyst, in which case the amount of catalyst used is the amount of esterified product supplied per unit time. 0.1 to 10 times the capacity.

Regarding the reaction pressure in the hydrogenolysis reaction of the present invention, generally speaking, the higher the hydrogen partial pressure, the easier the reaction will proceed, but for practical purposes, a hydrogen partial pressure of at least 100 kg/cm2G or higher is appropriate, particularly 130 kg/cm2G or higher. A hydrogen partial pressure of ~300 kB/c+n 2G is preferred.

The appropriate amount of hydrogen to be used is 2 to 4 equivalents per 1 equivalent of ester groups in the esterified product.

The hydrogen gas used in this reaction does not necessarily have to be of high purity, and N2, CH4, which does not have an adverse effect on the hydrogenolysis reaction,
It may also contain an inert component such as.

The first invention of the present application is characterized in that a monohydric alcohol having 4 or less carbon atoms is used as a solvent.

''-If the reaction temperature is raised to produce dihydric alcohol in high yield without using a solvent, C,ll1z,1(
C11z011)(CI(zOR), C,,112,2(CI+
20) 1) A hydroxy ether compound represented by (C1lzOR) (R is the alcohol residue, n is a positive number of 1 or more) is produced.

These hydroxyether compounds are the target compound 2
Separation by yellow distillation from the dihydric alcohol is extremely difficult, and highly pure dihydric alcohol cannot be obtained.

The reaction temperature is 150 to 300°C, preferably 180°C.
~230'C. If the temperature is 300°C or higher, the amount of side reaction products will increase, and if the temperature is 180°C or lower, the reaction rate will be slow, making it impractical.

In the present invention, any monohydric alcohol having 4 or less carbon atoms can be used as the solvent, but especially when methanol is used, the formation of hydroxy ether compounds can be effectively suppressed and the ester conversion rate can be increased. If an alcohol having 5 or more carbon atoms is used, the effect of suppressing the production of hydroxyether compounds will be reduced, and it will be difficult to separate the alcohol used as a solvent from the alcohol produced in the reaction. The amount of monohydric alcohol used as a solvent is 0.05 to 0.05 per weight of raw material ester.
10 parts, preferably 0.1 to 5 parts.

If the amount of monohydric alcohol used as a solvent is too small, it will not be effective in suppressing the formation of hydroxy ether compounds,
If the amount is too large, the size of the reactor will increase and the cost of solvent separation will increase.

Since the hydrogenolysis reaction is an exothermic reaction, the reaction temperature rises at the outlet side in an adiabatic reactor, and the higher the reaction temperature, the greater the amount of hydroxyether compound produced, which limits the maximum temperature of the reactor. By using the solvent of the present invention, the formation of hydroquine ether compounds can be suppressed, and this solvent can act as a diluent to reduce the temperature difference between the reactor inlet and outlet, thereby increasing the conversion rate. It also has the secondary effect of being able to.

Since the amount of hydroxyether compound produced is significantly suppressed by the method of the present invention, the desired high-purity dihydric alcohol can be easily obtained by distilling the reaction product. Furthermore, the monohydric alcohol produced as a by-product by the hydrogenolysis reaction and the monohydric alcohol used as the solvent have different boiling points and are therefore easily separated by distillation. The monohydric alcohol as a by-product from the separated hydrogenolysis reaction is recycled to the esterification reaction with saturated aliphatic dihydric carboxylic acids, and the monohydric alcohol in the separated solvent is recycled to the catalytic hydrogenolysis reactor. be able to.

(Example) Next, the present invention will be explained in more detail with reference to Examples. However, the present invention is not limited to these Examples.

Example 1 A commercially available barium-containing copper/chromite catalyst (Cu118 manufactured by Barshaw) was placed in a reaction tube with an inner diameter of 87 mmφ and a length of 1 mL.
4-T, CuO43X, CrzO345χ, Ba
O9χ, shape 1/8 x 1/8 inch pellet) 7
．． After reduction at 170°C or lower in a nitrogen stream containing 1 to 5x of hydrogen (catalyst filling capacity: 5.542), the hydrogen concentration was further increased to 100x, and reduction was carried out at 170 to 180°C for 1 hour.

Next, the pressure of the reaction tube was set to 200 kg/cm2G, the amount of hydrogen supplied was set to 27042/Hr at the outlet of the reaction tube, 80 wtx of di-2-ethylhexyl adipate with a sulfur content of 0.05 ppm (as SO2), and 20 w of methanol.
The raw material solution of tχ was preheated to 160°C at a rate of 3.1 kg/Hr (unit time of di-2-ethylhexyl adipate, r and sv per unit catalyst volume are 0.5 Hr") and the reaction tube was heated. Hydrogen was supplied from the top, and the reaction was carried out at a maximum temperature of 2106°C in the catalyst layer.

Examples 2 to 4 The reaction in Example 1 was carried out by changing the reaction temperature and methanol concentration.

Comparative examples 1-2 The reaction was carried out in the same manner as in Examples 1 and 2 without using a solvent.

Examples 5 to 6 In Example 1, the reaction was carried out by changing the LSV of the raw material ester and the methanol concentration.

LSV of raw material ester in Example 1 and Example 2
The reaction was carried out without using a solvent.

Examples 7 to 8 In Example 1, the reaction was carried out using di-2-ethylhexyl 1,3-cyclohexanedicarboxylate in place of the raw material di-2-ethylhexyl adipate.

Comparative examples 5-6 In Examples 7 and 8, the reactions were carried out without using a solvent.

In Example 1, a copper/chromite catalyst containing manganese (
Cu-1924-T manufactured by Barshaw, CuO46χ
, CrzO345χ, Mn0z9χ, shape 1/8 x
The reaction was carried out using n-butanol as a solvent.

The results of each example and comparative example are shown in Table 1. In Table 1, the diol obtained in Examples 1 to 6, Comparative Examples 1 to 4, and Example 9 is 1,6-hexanediol, and the diol obtained in Examples 7 to 8 and Comparative Examples 5 to 6 is 1.6-hexanediol. The diol is 13-hydroxymethylcyclohexane.

These Examples show that when a monohydric alcohol having 4 or less carbon atoms is used as a solvent, no hydroxyether compound is produced.

9 (Effect of the invention) In the method of the present invention, a saturated aliphatic or alicyclic divalent carboxylic acid, or a saturated aliphatic or alicyclic hydroxycarboxylic acid, and a monovalent carboxylic acid derived from an alkane having 6 or more carbon atoms. In the catalytic hydrogenolysis of esters with alcohols, the by-product of hydroxy ether compounds, which are an industrial problem, is eliminated, so the conversion rate of the reactor can be increased. Furthermore, the desired high-purity dihydric alcohol can be easily obtained by flower distillation of the reaction product.

As a result, industrial production of dihydric alcohol becomes easy, and the present invention has great industrial significance.

Claims (2)

[Claims] (1) An ester of a saturated aliphatic or alicyclic divalent carboxylic acid, or a saturated aliphatic or alicyclic hydroxycarboxylic acid, and a monohydric alcohol derived from an alkane having 6 or more carbon atoms. A method for producing a saturated aliphatic or alicyclic dihydric alcohol, characterized by catalytic hydrogenolysis in the presence of a monohydric alcohol of 4 or less. (2) The method for producing a saturated aliphatic or alicyclic dihydric alcohol according to claim 1, which comprises catalytic hydrogenolysis at a reaction temperature of 230°C or lower.