JPH0474143A - Production of neopentyl glycol - Google Patents

Abstract

PURPOSE:To obtain the subject substance useful as a plasticizer for acrylic resin, etc., synthetic lubricant, textile processing agent, etc., in high efficiency by hydrogenating hydroxypivalaldehyde in the presence of a catalyst containing Cu, Ni and P. CONSTITUTION:Hydroxypivalaldehyde produced by the aldol condensation of isobutylaldehyde and formaldehyde is hydrogenated in the presence of a catalyst to obtain the objective substance. The catalyst can be produced by mixing an aqueous solution of a Cu salt and an Ni salt with a precipitant (e.g. alkali metal hydroxide), adding a metal phosphate (e.g. lithium phosphate) to the obtained coprecipitate, drying the mixture at 80-130 deg.C and baking at 200-800 deg.C. The atomic ratio of Cu:Ni in the solution is 1:(0.05-2) and that of Cu+Ni to P is 1:(0.05-0.5). The catalyst has sufficiently high catalytic activity and selectiv ity and stable and long life.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a method for producing neopentyl glycol,
More specifically, hydroxypivalaldehyde obtained by condensing isobutyraldehyde and formaldehyde,
The present invention relates to a method for producing neopentyl glycol, which is characterized in that hydrogenation is carried out in the presence of a catalyst containing copper element, nickel element, and phosphorus element.

Neopentyl glycol has a wide range of industrial uses, such as acrylic resins, polyester resins, polyurethane resins, alkyd resins, polycarbonate resins, their base plasticizers, synthetic lubricating oils, fiber processing agents, and surfactants.
It is an extremely important intermediate raw material industrially.

(Prior art and its problems) There are two methods for producing neopentyl glycol as described below.

One is isobutyraldehyde and formaldehyde,
For example, in the presence of a strong alkaline catalyst such as caustic soda, caustic potash, or calcium hydroxide, there is a method in which a two-stage reaction consisting of an aldol condensation reaction and a cross-force nilaallo reaction is carried out to obtain the desired product, neopentyl glycol. However, in the case of this method, for example, when caustic soda is used, sodium formate is produced as a by-product in an amount equivalent to the target product, so unless this sodium formate is effectively used, it cannot be used as an industrial method for producing neopentyl glycol. It has the disadvantage of.

Another method is to hydrogenate hydroxypivalaldehyde obtained by the reaction of isobutyraldehyde and formaldehyde in the presence of a catalyst to obtain the desired product, neopentyl glycol, which does not involve by-products such as sodium formate. It's a method.

Regarding this hydrogenation method, Japanese Patent Publication No. 49-33169, Japanese Patent Publication No. 53-17568, British Patent Box 1゜219.162
No. 3, U.S. Patent No. 3. 920. No. 760, U.S. Patent No. 4,021,496, British Patent Box 1,048,530
No. 44,412, European Patent No. 44,444, and U.S. Patent No. 4,855,515 are known, and Raney N1 system,
N1-Cr series, Cu-Zn series, Cu-Al series, CuCr
A Cu-Cr-Ba system, a Cu-CrMn system, and the like are disclosed.

However, these known catalysts have problems in that the catalytic activity is not sufficient and the reaction must be carried out under high pressure conditions, and furthermore, the catalyst life is not sufficient and it is not possible to maintain satisfactory catalytic activity for a long period of time. .

In the case of Raney type catalysts, in addition to having shortcomings in catalytic activity and sustainability, catalyst preparation and handling are not easy, and the process is complicated because it is used in the form of a slurry, which is not favorable for the process. There are various problems such as

Further, in the case of a catalyst containing the element chromium, since the chromium compound is toxic, strict care must be taken in the production and handling of the catalyst, making it undesirable as an industrial catalyst.

(Means for Solving the Problems) The present inventors have conducted intensive research to solve the above-mentioned drawbacks in a method for producing neopentyl glycol by hydrogenating hydroxypivalaldehyde, and have found that copper oxide,
It was discovered that a catalyst containing nickel oxide and a metal salt of phosphoric acid has extremely excellent catalytic performance, and the present invention was completed.

That is, in the present invention, in the presence of a catalyst containing a copper element, a nickel element, and a phosphorus element, water or methanol
Hydroxypival obtained by condensing isobutyraldehyde and formaldehyde in the presence of the above alcohols, ethers such as butyl ether and dioxane, or solvents such as saturated hydrocarbons such as n-heptane, or a mixed solvent thereof. The present invention provides a method for stably producing neopentyl glycol in high yield by hydrogenating aldehyde.

The present invention will be explained in detail below.

Hydroxypivaldehyde used in the present invention can be easily obtained by an aldol condensation reaction of isobutyraldehyde and formaldehyde in the presence of a basic catalyst. For example, the molar ratio of isobutyraldehyde to 1 mole of formaldehyde is set to 0.8 to 1.3 times, preferably 1.1 to 1.2 times, and in the presence of a tertiary amine catalyst such as trimethylamine or triethylamine. A method in which the condensation reaction is carried out at 15 to 95 °C, or in the presence of a strong alkaline catalyst such as caustic soda.
It can be obtained by a method of carrying out a condensation reaction at 5 to 40°C.

The raw material hydroxypivalaldehyde used in the method of the present invention is one obtained by removing unreacted isobutyraldehyde and formaldehyde from the aldol condensation reaction product liquid, or a mixture of these unreacted aldehydes and a catalyst.
A product from which grade amines have been removed or a reaction product solution as it is can be used. Furthermore, after removing unreacted isobutyraldehyde and formaldehyde from the aldol condensation reaction product solution, a dimer of hydroxypivalaldehyde can be crystallized in water and used as a raw material. Since this dimer participates in the hydrogenation reaction as a hydroxypivalaldehyde monomer, it can be applied to the method of the present invention without any problem. Alternatively, a solution obtained by extracting hydroxypivalaldehyde from an aldol condensation liquid using an alcohol of 04 or higher can also be used as a raw material.

When carrying out the method of the present invention, a feed stock solution is prepared using an appropriate amount of water, alcohol, or a mixture thereof as a solvent for the above-mentioned hydroxypivalaldehyde, and then in the presence of the catalyst of the present invention. Perform hydrogenation reaction. When the catalyst of the present invention is used, the amount of impurities such as unreacted isobutyraldehyde, formaldehyde, tertiary amines, amine compounds derived therefrom, and formates contained in the raw material solution is up to 5 wt%. is allowed.

When the dimer of hydroxypivalaldehyde obtained by crystallization from the aldol condensation reaction solution of isobutyraldehyde and formaldehyde is used as a raw material, it is preferably dissolved in a solvent, and water, alcohols such as methanol, and Mixtures of these are preferably used. When water and methanol are mixed to be used as a solvent, the two can be mixed in any ratio.

The catalyst of the present invention is a catalyst containing a copper element, a nickel element, and a phosphorus element, and a catalyst containing copper oxide, nickel oxide, and a metal salt of phosphoric acid is particularly preferable.

The catalyst preparation method of the present invention is not particularly limited, and can be prepared by conventionally known methods.

For example, copper oxide, nickel oxide, and a metal salt of phosphoric acid can be mixed in powder form or in a paste form by adding water, and then molded to form a catalyst.

Alternatively, the precipitate obtained from the soluble salts of copper and nickel and the precipitant can be made into copper oxide and nickel oxide, which can be mixed with a metal salt of phosphoric acid and shaped into a catalyst.

In particular, when considering the stability and reproducibility of catalyst performance, it is recommended to mix the precipitate obtained by mixing an aqueous solution of a copper salt and an aqueous precipitant solution with an aqueous solution of a nickel salt and an aqueous precipitant solution. A catalyst preparation method in which a metal salt of phosphoric acid is added to the resulting precipitate or a coprecipitate obtained by mixing a mixed aqueous solution of copper and nickel salts and a precipitant is preferred. In this preparation method, the raw materials copper and nickel used are preferably water-soluble salts, such as nitrates, hydrochlorides, sulfates, acetates, and the like. In addition, the precipitating agent used for precipitation generation is a conventionally known precipitating agent, such as alkali and alkaline earth metal hydroxides, aqueous ammonia,
Or their carbonates, bicarbonates, etc.

The ratio of copper to nickel in the catalyst of the present invention is 0.01 to 5 atoms of nickel per 1 atom of copper, preferably 0.05
~2 atoms. If the amount of nickel is less than this range, the catalyst activity will be low and acetal compounds of neopentyl glycol and hydroxypivalaldehyde will also be produced as by-products, whereas if it is more than this range, by-products due to hydrogenolysis etc. will be produced. occurs more easily, and the catalyst life is also shortened.

The metal salts of phosphoric acid used in the catalyst of the present invention are metal salts of orthophosphoric acid, pyrophosphoric acid, polyphosphoric acid, metaphosphoric acid, phosphorous acid, and hypophosphorous acid, and specifically, lithium phosphate, phosphorous acid, etc. Acid copper, calcium phosphate, calcium hydrogen phosphate, calcium dihydrogen phosphate, barium phosphate, strontium hydrogen phosphate, aluminum phosphate, lead phosphate,
Orthophosphates such as titanium phosphate, manganese hephosphate, cobalt phosphate, pyrophosphates such as zinc pyrophosphate, magnesium pyrophosphate, manganese pyrophosphate, polyphosphates such as calcium tripolyphosphate, calcium metaphosphate, lithium metaphosphate, aluminum metaphosphate Examples include metaphosphates such as, calcium phosphite, phosphites such as calcium phosphite, hypophosphites such as manganese hypophosphite, and magnesium hypophosphite.

The amount of phosphate added in the catalyst of the present invention is 0.01-1 atomic ratio of phosphate metal per metal, preferably 0.05-0.
5 atomic ratio. If the amount of the metal salt of phosphoric acid added is less than this range, the catalytic activity will be low, and if it is too much, by-products are likely to be produced and the selectivity to the target reaction will be reduced.

Note that the metal salt of phosphoric acid used may contain an alkali metal compound as an impurity, but this does not interfere with this reaction.

The catalyst precursor mixture prepared as described above is dried at a temperature higher than room temperature, preferably 80 to 130°C.
After firing at 0 to 800°C, molding according to the embodiment,
Used as a catalyst in the present invention.

When forming the catalyst, fillers such as diatomaceous earth, silica, and graphite can be mixed to an extent that does not inhibit the hydrogenation reaction. These fillers may be added when the copper and nickel precipitates are formed, or when the precipitates are mixed with the metal salt of phosphoric acid.

The catalyst of the present invention is preferably reduced and activated with a reducing gas such as reserved hydrogen before being subjected to the reaction, but it can also be activated by introducing methanol vapor into the reactor.

The method of the invention will be explained in more detail below.

The concentration of hydroxypivalaldehyde in the raw material solution to be subjected to the hydrogenation reaction is 5 to 80% by weight, particularly preferably 15 to 60% by weight. If the concentration is more dilute than this, it will be difficult to separate the neopentyl glycol produced from the solvent and the energy burden for evaporative dehydration will increase, and if the concentration is higher than this, the hydroxypivalaldehyde The Tishienko reaction occurs,
This is industrially undesirable as hydroxypivalic acid neopentyl glycol ester is produced as a by-product.

When carrying out the method of the present invention, copper oxide, nickel oxide, The hydrogenation reaction of hydroxypivalaldehyde is carried out by dispersing or suspending a catalyst containing a metal salt of phosphoric acid and a metal salt of phosphoric acid, or by supplying a raw material solution to a column packed with the catalyst.

The hydrogenation reaction can be carried out either continuously or batchwise.

The reaction temperature is 60-250°C, preferably 80-250°C.
The temperature range is 200°C.

The reaction pressure is in the range of 1 to 150 Kg/cm'', preferably 5 to 80 Kg/cm', and hydrogen is introduced to maintain the pressure of the reaction system.

After the reaction is completed, the target product neopentyl glycol is separated and recovered from the reaction product solution by applying a distillation method, a solvent extraction method, or the like.

Although the reaction proceeds even outside the above range of reaction conditions, when the method of the present invention is carried out under the above range of reaction conditions, neopentyl glycol can be obtained with high yield and high selectivity.

(Effects of the Invention) According to the method of the present invention, in the method of hydrogenating hydroxypivalaldehyde to produce neopentyl glycol, it is possible to achieve industrial benefits by developing a stable and long-life catalyst with sufficient catalytic activity and selectivity. The significance is profound.

〔Example〕

The method of the present invention will be explained in more detail below with reference to Examples, but the scope of the present invention is not limited by these Examples.

In Examples and Comparative Examples, HPA
, N.P.G., I.B.A.

They are abbreviated as TEA and HPNE.

Further, the catalyst composition is expressed by the atomic ratio of copper and nickel, and the atomic ratio of the metal for the metal salt of phosphoric acid.

Example 1 0.5 mol of copper nitrate (trihydrate) and nickel nitrate (hexahydrate)
0.05 mol was placed in a 5-liter flask, and 1.2 liters of ion-exchanged water was added to dissolve it.

Separately, 0.65 anhydrous sodium carbonate in a 3 liter beaker
1.2 liters of ion-exchanged water was added to dissolve the solution, and the temperature was maintained at 40°C.

A 5-liter flask was kept at 40 to 42° C. with stirring, and the entire amount of the aqueous sodium carbonate solution was poured into the flask and maintained for 1 hour.
Thereafter, the temperature was raised to 80° C. over 40 minutes, and cooled after 1 hour. The generated precipitate was filtered and washed with ion-exchanged water. Add 0.32 mol of aluminum phosphate to this precipitate, mix uniformly in a vest, dry at 115°C,
It was fired at 350°C. Next, graphite was added and the mixture was compressed into tablets. This catalyst is crushed into 8 to 12 meshes,
It was reduced and activated at 170°C under a N2-H2 mixed gas stream.

In a stainless steel autoclave with an internal volume of 100 m1, 3
．． 8 g of HPA powder, water as a solvent, and 1 g of an activated catalyst were charged, the autoclave was capped, and the inside of the autoclave was sufficiently purged with hydrogen gas, and hydrogen gas was introduced up to 20 kg/cm2.

Place the autoclave on a shaking table, and while shaking
The temperature was raised to 00°C to cause a reaction. After the reaction was completed, the autoclave was cooled with ice water, the residual pressure inside the autoclave was purged, and the reaction solution was analyzed by gas chromatography.

The experimental results are shown in Table 1 along with the reaction conditions.

Examples 2 to 7 Catalysts containing phosphates of different metal species were prepared in the same manner as in Example 1.

Using these catalysts, HPA powder or 25w of HPA
An HPA hydrogenation experiment was conducted in the same manner as in Example 1 using a t% solution or an aldol condensation liquid as a raw material.

The experimental results are shown in Table 1.2.3 along with the reaction conditions.

The aldol condensation liquid used in each experiment was prepared by reacting a 40% aqueous formalin solution, IBA, and triethylamine, and adding water so that the HPAa content was 25 wt%. Other compositions are IBA (), 4
wt%, TEA (1.5 wt%, methanol l,
5 wt%, water 70.2 wt%, NPNE
l, Qwt%, NPG Q, 9wt%, others 0.4
It was Wt%.

Example 8 Copper nitrate, nickel nitrate, carbonate (copper nitrate, nickel nitrate, carbonate) Using IJium and aluminum phosphate as raw materials, the atomic ratio of copper, nickel, and aluminum was each 1 by the same method as in Example 1.
．． A catalyst consisting of copper oxide and aluminum oxidized nickenovelinate having a component ratio of 0.05.0.29 was prepared and molded into a cylindrical shape with a diameter of 3 mm and a height of 3 mm. This catalyst 1
Fill a stainless steel single-tube reactor with 5 Qml of raw material H.
The PA solution and hydrogen were continuously introduced, and the reaction was continued for 50 days. The raw material HPA was supplied as a 2 Q wt% warm solution of water-methanol-112 weight ratio).

The reaction conditions and results are shown in Table 4. As a result, high catalytic activity could be maintained for a long time.

Comparative Examples 1 to 5 Catalysts made of copper oxide and aluminum phosphate prepared in the same manner as Examples 1 to 7, catalysts made of nickel oxide and aluminum phosphate, catalysts made of copper oxide and nickel oxide, and commercially available catalysts The same procedures as in Examples 1 to 7 were conducted except that a catalyst (N-201, manufactured by JGC Chemical Co., Ltd.) consisting of copper, chromium, and manganese was used.

The reaction conditions and results of each comparative catalyst are shown in Table 5.

Table-1 Table-2 table Example Table-4 Reaction days (Day)

Claims (1)

[Claims] When hydrogenating hydroxypivalaldehyde to produce neopentyl glycol, copper element, nickel element,
and a method for producing neopentyl glycol, which comprises using a catalyst containing the element phosphorus.