JPS6011438A - Production of ethylene glycol dialkyl ether - Google Patents

Abstract

PURPOSE:To provide the titled compound useful as various solvents, etc., easily in high yield, by the catalytic reaction of an ethylene glycol monoalkyl ether with a compound containing carbonyl group in the presence of hydrogen using a palladium catalyst containing carbon black as the carrier. CONSTITUTION:The objective compound is obtained by reacting an ethylene glycol monoalkyl ether (e.g. ethylene glycol monomethyl ether) with a carbonyl- containing compound (e.g. acetone) in the presence of hydrogen and a catalyst obtained by supporting a palladium compound such as palladium chloride, palladium nitrate, palladium hydroxide, etc. to a carbon black carrier such as furnace black, acetylene black, thermally cracked carbon, channel carbon, etc. The alkyl group of the objective compound can be changed easily by selecting the kind of the raw material.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a method for producing ethylene glycol dialkyl ether by catalytically reacting ethylene glycol monoalkyl ether with a carbonyl group-containing compound in the presence of hydrogen.

By using the method of the present invention, desired ethylene glycol dialkyl ether can be efficiently produced.

The ethylene glycol dialkyl ether obtained by the method of the present invention is used industrially as a variety of solvents, as well as as an extractant, an absorbent, a 1-stooth cleaner, and the like.

Prior Art Although there is no prior art related to the method of the present invention which directly produces ethylene glycol dialkyl ether by reacting ethylene glycol monoalkyl ether with a carbonyl group-containing compound, it is possible to react an alcohol and a carbonyl compound in the presence of a catalyst in a hydrogen atmosphere. The following methods are available to synthesize ether.

■ M, VerzelJ3et al, -, J-Ch
em-Soc, 559B (1963) Using platinum oxide as a catalyst, an ether is obtained by the reaction of an alcohol and mainly a ketone in a hydrogen atmosphere and the presence of hydrogen chloride. 2-methoxypropane is produced by reacting acetone and methanol in a hydrogen atmosphere using platinum or palladium supported on a sulfonic acid type ion exchange resin.

The present inventors applied the above-mentioned prior art method to the reaction with ethylene glycol monoalkyl ether carbonyl compounds, and found that (1) the activity and selectivity were not satisfactory; (2) the use of acid was not suitable for the equipment; It was found that there were some problems, such as unfavorable materials, waste disposal, etc. ■ Platinum is very expensive.

On the other hand, as a method for producing ethylene glycol dialkyl ethers, ① ethylene glycols or monoalkyl ethers are used as sodium alkoxide and alkylated with an alkyl halide. The following methods are known: (1) a method of hydrogenolyzing an acetal compound of ethylene glycol monoalkyl ethers, and (2) a method of reacting ethylene oxide with an ether.

However, the above method 0 uses expensive metallic sodium, requires alkali-resistant and halogen-resistant equipment, and requires a large amount of expense for wastewater treatment. Method (2) is not an economical method if there are problems in producing the acetal compound as a raw material. ■The method is
Known methods for producing ethylene glycol dialkyl ethers also have problems, such as the product having a wide distribution due to the number of ethylene oxides added, making separation of the target product extremely difficult.

SUMMARY OF THE INVENTION The present inventors have conducted intensive studies to solve the above problems and have completed the present invention.

That is, the present invention provides a method for producing ethylene glycol dialkyl ether by catalytically reacting ethylene glycol monoalkyl ether and a carbonyl group-containing compound in the presence of hydrogen, in which a palladium catalyst having carbon black as a carrier is used as the catalyst. The present invention provides a method for producing ethylene glycol dialkyl ether.

jll lyso (According to the method of the present invention, the alkyl group of the target ethylene glycol dialkyl ether can be easily changed by selecting the raw materials, and the reaction is easy and the target product can be produced in high yield. can.

3. Detailed Description of the Invention The palladium catalyst using carbon black as a carrier used in the method of the present invention uses carbon flicks such as furnace carbon, acetylene black, pyrolytic carbon, channel carbon, etc. as a carrier.

There are no particular restrictions on the method of supporting the palladium component on the carbon carrier, but the palladium component may be supported on the carbon carrier, which has been washed if desired, by any means known per se.

Examples of such loading methods include, for example, loading under reducing conditions with alkali-formalin, loading under liquid phase hydrogen reducing conditions, or loading palladium salts and then using hydrogen or other reducing agents. A method of reducing palladium to gold scraps on a carrier, and other methods (for example, 1 process).

Mozingo” Organic 5ynthes
is Vol, 26P77 ('46)).

The palladium raw material to be used is not particularly limited, but examples include palladium compounds such as palladium chloride, palladium nitrate, palladium hydroxide, palladium acetylacetonate, palladium ammonium chloride (potassium, sodium), and palladium sulfate. can. Palladium chloride is usually used from the viewpoint of stability, cost, etc. The supported amount of palladium can be selected as appropriate, but is, for example, about 0.1 to about 10 wt%, more preferably about 0.5 to about 10 wt%. Approximately 5
An example of the supported amount is wt%.

The ethylene glycol monoalkyl ether used in the method of the present invention is represented by the following formula (1).

RI O-(CH2CH20+n H-(1) where R
+ can be any alkyl group, but usually C1 to C8,
Preferably, it is a C1-C4 straight chain or branched alkyl group, and n is a positive integer, usually 1-8, preferably 1-4.

Specific examples of the ethylene glycol monoalkyl ether represented by the above general formula (1) include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monomethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, and diethylene glycol Examples include motuputyl ether and tetraethylene glycol monomethyl ether.

Further, the carbonyl group-containing compound is represented by the following formula (H), where R2 and R3 represent hydrogen or any alkyl group, except when R2 and R3 are both hydrogen, that is, formaldehyde is excluded. When R2 and/or R3 are alkyl groups, C1 to C8 are usually used, preferably Cs-C4. Specific examples of these include aldehydes such as acetaldehyde, propionaldehyde, butyraldehyde, and isobutyraldehyde, and ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone.

The method of the present invention requires that the above-mentioned ethylene glycol monoalkyl ether and the carbonyl group-containing compound are reacted in the presence of hydrogen using the above-mentioned palladium catalyst using carbon black as a carrier. This can be carried out according to known catalytic hydrogenolysis techniques.

The reaction temperature may be, for example, room temperature to about 250°C, more preferably room temperature to about 150°C. Under the binding parameter conditions of the present invention, there is an advantage that the reaction can be carried out under relatively low hydrogen pressure conditions. The pressure conditions include, for example, normal pressure to about 200 atmospheres,
Preferred examples include hydrogen pressure conditions such as normal pressure to about 50 atmospheres.

Raw material ethylene glycol monoalkyl ether/
Carbonyl group-containing compound in a molar ratio of 1/1 to 50/1
, preferably 1/1 to 25/l, with hydrogen in a catalytic hydrocracking reaction zone.

It can be carried out in a continuous mode, or it can be carried out in a continuous mode, for example, with continuous withdrawal from the reaction zone in the vapor phase. Furthermore, the reaction can be carried out in a fixed bed mode, for example by preparing the catalyst in a suitable shaped catalyst shape suitable for implementation in a fixed bed mode.

In the reaction, the raw materials can be used without being diluted or diluted with an appropriate solvent.

Examples of such solvents include the target compound itself, ethers such as dioxane, and inert organic solvents such as hydrocarbons such as cyclohexane and benzene.

can.

EXPERIMENTAL EXAMPLES Several embodiments of the method of the present invention will be illustrated in more detail in the following examples.

Catalyst Preparation Example-1゜(PdC1z aqueous solution) Pdctz 12.00 gr (Pd Toshitare, 20
gr ) was dissolved in a 1 t volumetric flask by adding 25 gr of hydrochloric acid, and demineralized water was added to bring the solution to 1 o, oom/. This solution contains 72.0119 as Pd in 10 grams.

(Catalyst Preparation) Carbon black (Ketchen Ec: Lion Akzo product: specific surface area s 5 srr?, / gr ),
0.4. sri in 240 ytl of NaOH, 60
After stirring for 1 hour at ℃, the mixture was filtered, washed with 1 ton of boiling water, and dried. Treatment carrier 4.8 gr o, 1N NaOH1 o
o rrtl, suspended in demineralized water zooml, and the above Pd
Add 30 ml of C/,z solution over 45 minutes with stirring, and add 1
After stirring for an hour, it was filtered and washed with 1 ton of boiling water. 400
ml of demineralized water, hydrogen was bubbled into the solution for 30 minutes under stirring at a temperature of 70°C, and then filtered.
Wash with 1 ml of boiling water and dry at 110°C overnight to reduce the
A wt% Pd supported catalyst was prepared (hereinafter referred to as 5% Pd/K
-EC (sometimes abbreviated as C).

Catalyst preparation example - 2° carbon black (430: Mitsubishi Kasei product; specific surface area 67.8 n?/51) 2.4 gr in demineralized water 2
00ml, suspended in xoml of the aforementioned PdC62 aqueous solution
added.

While stirring, 37% formalin aqueous solution o, xrnl was added over 5 minutes, and 0. 40 ml of an aqueous solution of IN in NaOH was added, and the temperature was raised to 50°C and maintained for 30 minutes. After filtration, it was washed with 5 oomt of boiling water, dried at 110°C overnight, placed in a glass reaction tube, and heated at 150°C under a stream of H2 for 2.5 oz.
hrs was further reduced to prepare about 3% Pd supported catalyst (
Hereinafter, it may be abbreviated as 3% pd/4p 30).

Catalyst Preparation Example - 3 The above preparation example - except that carbon black (MA600: Mitsubishi Kasei product: specific surface area 125 m'/f) was used.
1, a 5% Pd supported catalyst (hereinafter, 5% Pd
/MA 600) was prepared.

Catalyst Preparation Example - 4° Acetylene Black (Ibiyo Denko Co., Ltd. product; specific surface area: 64
．． A 5% Pd-supported catalyst was prepared in the same manner as in Preparation Example-1 except that 9+♂/2) was used (hereinafter, 5%
(sometimes abbreviated as Pd/A B).

Example 1 In a 50 ml glass autoclave with electromagnetic stirring, 3 t mol of ethylene glycol monomethyl ether (hereinafter referred to as methyl cellosolve), 0.02 mol of acetone, and catalyst preparation example 1 (5% Pd/N) were added. EC) 0.5
After charging gr and replacing the system with hydrogen, the hydrogen pressure was reduced to 3
．． The temperature was raised with stirring at sKp/iG, and when it reached 100°C, it was kept at that temperature and the pressure was increased to 5.0 Kg/crl.
G and reacted for 5 hours. After the reaction was completed, stirring was stopped, the mixture was cooled, and the catalyst was separated from the contents. The product was analyzed by gas chromatography, and the following results were obtained.

Acetone conversion rate: 66.5% Ethylene glycol methyl isopropyl ether (hereinafter referred to as ether) selectivity: 91.9% Isopropyl alcohol selectivity: 4.8% As can be seen from this example, the desired ether can be obtained with high selectivity.

Comparative Example-1 In Example-1, Amberlyst 152.0
The reaction was carried out in the same manner as in Example 1, except that gr (sulfonic acid type ion exchange resin manufactured by Rohm & Co., Ltd.) was added and the reaction time was changed to 2 hours. The results are shown in Table-1.

Comparative Example-2 A reaction was carried out in the same manner as in Example-1, except that a 5% PdJ carbon catalyst (Loty% 3514) purchased from Engelhard was used as the catalyst in Example-1. Table 1 shows the results.
It is written in

Comparative Example-3 The catalyst in Example-1 was replaced with a 5% Pd/alumina catalyst (Lot I6.63) purchased from Engelhardt.
The reaction was carried out in the same manner as in Example-1 except that . The results are shown in Table-1.

Comparative Example-4 In Comparative Example-2, Amberlyst 15 was further added to 1.0
The reaction was carried out in the same manner as in Comparative Example 2, except that gr was added and the reaction time was changed to 3 hours. The results are shown in Table-1.

Comparative Example-5 Comparative Example-3 (Later, Amberlyst 15 was added to 1.
The reaction was carried out in the same manner as in Comparative Example-3 except that 0 gr was added. The results are shown in Table-1.

Example-2 Catalyst preparation example-203%Pd/
The reaction was carried out in the same manner as in Example-1 except that = #30.

The results are shown in Table-1.

Example-3 The catalyst in Example-1 was replaced with 5% Pd/Catalyst Preparation Example-3.
The reaction was carried out in the same manner as in Example-1 except that MA 6o was used. The results are shown in Table-1.

Example-4 The catalyst in Example-1 was mixed with 5% Pd/
The reaction was carried out in the same manner as in Example-1 except that A and B were used. The results are shown in Table-1.

From Examples 1 to 4 and Comparative Examples 1 to 5, the carbon black-supported Pd catalyst is very superior to activated carbon or At203-supported Pd, whereas the latter produces ether only in the presence of an acid. It is clear that the former produces ether even in the absence of acid, and that the selectivity is better in the absence of acid.

(Left below) Example-5 The reaction was carried out in the same manner as in Example-1 except that methyl ethyl ketone was used instead of acetone.
The following results were obtained.

Ethylene glycol methyl isobutyl ether production amount 7
．． 2 mmot Inbutyl alcohol production amount 0, 5 mmol Example-6 (acetone/methyl cellosolve ratio) Same as Example-1 except that the amount of acetone was 100 mmot and the amount of methyl cellosolve was 25 Q mmo4. A similar reaction was carried out and the following results were obtained.

Ethylene glycol methyl isopropyl ether production amount 27.0m mot Inglovir alcohol production amount 3.8mmot Example-
7 The reaction was carried out in the same manner as in Example-1, except that n-butyraldehyde was used instead of acetone in Example-1, and the following results were obtained.

Amount of ethylene glycol methyl normal butyl ether produced: 14.0 mmot 1.7 mmot of methyl cellosolve acetal of butyraldehyde having the following structure was detected as a by-product.

(2)-Butyl alcohol was 0.1 mmot or less.

Comparative Example-6 In Example-7, n-butyraldehyde was reacted with caete paraformaldehyde (purity 80%, analysis value by sodium sulfate method) in the same manner as in Example-7 except that HCI (20 mm01 was used as 0). The following results were obtained.

Ethylene glycol dimethyl ether production amount 0.4 m
mot As the main product, methyl cellosolve formaldehyde having the following structure was obtained.

As is clear from Example 7 and Comparative Example 6, when HCHO is used as the aldehyde, formalization progresses, but when an alkyl aldehyde is used, the desired diether can be easily obtained.

Patent Applicant Mitsubishi Yuka Co., Ltd. Patent Applicant Mitsubishi Yuka Fine Co., Ltd. Agent Patent Attorney Hidetoshi Utsuyoshi Patent Attorney Masahisa Hase 314-

Claims (1)

[Claims] (1) In a method for producing ethylene glycol dialkyl ether by catalytically reacting ethylene glycol monoalkyl ether and a carbonyl group-containing compound in the presence of hydrogen, a palladium catalyst having carbon black as a carrier is used as the catalyst. Characteristic method for producing ethylene glycol dialkyl ether.