JPH1072455A - Production of epoxidized products of olefin compounds - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable to obtain the subject compound useful as a raw material for glycol compounds, etc., in high selectivity without requiring a highly concentrated hydrogen peroxide aqueous solution by oxidizing an olefin compound with a specific oxidative alcoholic solvent solution. SOLUTION: This method for producing the epoxidized product of (C) an olefinic compound comprises oxidizing (C) the olefinic compound such as propylene with (A) an alcoholic solvent hydrogen peroxide solution in the presence of (B) an oxidation catalyst such as a titanosilicate (e.g. the titanosilicate having an Si/Ti atomic ratio of 10-1000). The alcoholic solvent hydrogen peroxide solution is obtained by catalytically reacting (A1 ) hydrogen with (A2 ) oxygen [preferably in the presence of a platinum group metal (compound) (e.g. palladium chloride, palladium bromide)] in (A) an alcoholic solvent (preferably methanol, ethanol).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing an epoxidized olefin. More specifically, the present invention relates to a method for producing an epoxidized olefin by reacting the olefin with hydrogen peroxide in an alcoholic medium.

[0002]

2. Description of the Related Art Epoxidized olefins, especially propylene oxide, are one of important industrial products as raw materials for propylene glycol, polypropylene glycol and the like. As a general industrial production method of propylene oxide, a chlorhydrin method, a Halcon method, a peracetic acid method and the like are known. However, these methods have a problem in that a large amount of by-products are co-produced, and it is necessary to secure a market for co-products.

On the other hand, the method using hydrogen peroxide in the presence of a titanium compound is advantageous in that a large amount of by-products is not co-produced (for example, Japanese Patent Publication No. 4-5028, US Pat. No. 5,354,875). Statement). For example,
Japanese Patent No. 5028 discloses that olefin can be epoxidized with high yield and high selectivity using hydrogen peroxide as an oxidizing agent by using crystalline titanosilicate as a catalyst in an alcoholic medium. There was a problem that hydrogen oxide was used.

When the medium of hydrogen peroxide as a raw material is an aqueous medium, it is necessary to dilute the medium with an organic solvent such as alcohol which is an efficient medium in the process of producing epoxides. For example, it is conceivable to dilute a 30 wt% aqueous hydrogen peroxide solution with methanol and use it as a 5 wt% hydrogen peroxide solution in which methanol is the main solvent in the epoxide production process. Therefore, in order to ensure a certain concentration of hydrogen peroxide used in the epoxide production process, it was necessary to produce a hydrogen peroxide solution having a higher concentration in advance than that.

[0005] A high-concentration aqueous solution of hydrogen peroxide requires a concentration step, which complicates the process and is expensive. In addition, there is the danger of high concentrations,
There are many problems, such as the necessity of a step of diluting with alcohol, and the fact that a large amount of water is contained, so that by-products such as glycol are increased in the process of producing epoxidized products.

[0006] The most common industrial production method of hydrogen peroxide at present is based on an autoxidation method using alkylanthraquinone. But the problem with this method is that
Many steps such as reduction and oxidation of alkylanthraquinone and extraction separation, purification, and concentration of generated hydrogen peroxide are required, and the process is complicated. There are also problems such as loss of alkylanthraquinone and deterioration of the reduction catalyst.

[0007] In order to solve these problems, there has been proposed a method for directly synthesizing hydrogen peroxide by bringing hydrogen and oxygen into contact with each other in an aqueous medium in the presence of a platinum group metal (Japanese Patent Publication No. 55-1979). No. 18646, Japanese Patent Publication No. 1-2340
No. 1, JP-A-63-156005, etc.). For example, in JP-A-63-156005, a somewhat high concentration aqueous solution of hydrogen peroxide can be produced from hydrogen and oxygen in an aqueous medium containing acid and halide ions in the presence of a platinum group metal supported on a support. And However, all of these produce hydrogen peroxide in an aqueous medium, and it is necessary to dilute with an organic solvent to use it as a raw material for epoxidation of olefins. I had to.

Further, in these methods, in order to obtain an aqueous solution of hydrogen peroxide having a concentration as high as possible, it was necessary to carry out the reaction under high pressure conditions. The production of hydrogen peroxide under high pressure conditions is costly for constructing various facilities and is industrially disadvantageous. In consideration of reacting an explosive combination of hydrogen and oxygen, high-pressure conditions are not preferable in terms of safety. It is important to establish a method for efficiently producing hydrogen peroxide even under low pressure conditions and to effectively use it for producing olefin epoxides.

Japanese Patent Application Laid-Open No. 57-92506 discloses that alcohol, ketone, ether, ester, amide and the like can be used as a reaction medium, but methanol is particularly excellent. However, in order to obtain a hydrogen peroxide solution to some extent efficiently, it was necessary to coexist formaldehyde in the reaction medium in order to suppress the decomposition of the generated hydrogen peroxide. Therefore, there is a problem that a step for adding and a purification step for removing are required, which complicates the process and that formaldehyde may suppress the catalytic activity.

[0010]

The problem to be solved by the present invention, that is, the object of the present invention is to provide a high-concentration aqueous solution without the need for a high-concentration aqueous solution of hydrogen peroxide, An object of the present invention is to provide a method for producing epoxidized olefins with high selectivity.

[0011]

Means for Solving the Problems In view of the above situation, the present inventors have conducted intensive studies and completed the present invention. That is, the present invention uses an alcoholic medium solution of hydrogen peroxide produced by catalytically reacting hydrogen and oxygen in an alcoholic medium, and oxidizes olefins in the presence of an oxidation catalyst. It depends on the manufacturing method.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. (1) Production of Hydrogen Peroxide In the present invention, an alcoholic medium is used as a reaction medium when producing hydrogen peroxide. The alcoholic medium referred to in the present invention refers to an alcohol or a mixture containing alcohol as a main component, and other components in the case of a mixture containing alcohol as a main component include ketones, ethers, esters,
Amides, water and the like. More preferably, an alcoholic medium is used as the alcoholic medium. As the alcohol, methanol, ethanol, isopropanol, butanol, ethylene glycol and the like are used, but methanol and ethanol are preferred, and methanol is more preferred.

In the present invention, when producing hydrogen peroxide by catalytically reacting hydrogen and oxygen, it is preferable to carry out the reaction in the presence of a platinum group metal or a compound of a platinum group metal.

Preferably, the hydrogen peroxide of the present invention is produced by catalytically reacting hydrogen and oxygen in an alcoholic medium in the presence of a halogen compound of a platinum group metal. With this, epoxidized olefins can be used without the need for a high-concentration aqueous hydrogen peroxide solution, and without addition of acids, compounds that dissociate to produce halide ions, or formaldehyde. Hydrogen peroxide suitable as a production reagent can be produced, which is preferable.

Here, as the platinum group metal in the halogen compound of the platinum group metal, rhodium, iridium, platinum, palladium and the like can be mentioned. Preferably, platinum or palladium is used, and more preferably, palladium is used. As the halogen compound, a fluorine compound, a chlorine compound, a bromine compound or an iodine compound is used, and a chlorine compound or a bromine compound is preferably used. Specific examples of such a halogen compound of a platinum group metal include rhodium chloride, rhodium bromide, iridium chloride, iridium bromide, platinum chloride, platinum bromide, palladium fluoride, palladium chloride, palladium bromide, palladium iodide, and dichlorodichloromethane. Diammine palladium and the like. Particularly preferred is palladium chloride or palladium bromide.

The reaction may be either a continuous system or a batch system, and the reaction apparatus may be a suspension bed system, a fixed bed system, or the like. The amount of the halogen compound of the platinum group metal is not particularly limited.
1 mg or more and 10 g or less, preferably 10 m per ml
g and 10 g or less. The form of the halogen compound of the platinum group metal may be in any form such as a fine powder or a pellet, but is preferably a fine powder, and the surface area is 0.01 to
Those having 10,000 m ² / g are more preferably used.
The halogen compound of the platinum group metal can be used as it is,
It is also possible to use it supported on a suitable carrier. In general, the more hydrogen is carried, the greater the yield of hydrogen peroxide per metal weight.

Examples of the carrier include alumina, silica, titania, magnesia, zirconia, ceria, zeolite, graphite, activated carbon, silica gel, hydrated silica, silicon carbide, etc., and alumina, silica, titania, zeolite, graphite or activated carbon Is preferably used. As a method of supporting on a carrier, for example,
Suspending the carrier in a solution of a platinum group metal halide,
There is no particular limitation as long as it can be supported, such as a method of evaporating to dryness.

The hydrogen peroxide of the present invention is obtained by catalytically reacting hydrogen and oxygen in an alcoholic medium containing an acid and a halide of an alkali metal or an alkaline earth metal in the presence of a platinum group metal. The manufactured product can also produce hydrogen peroxide suitable as a reagent for producing epoxidized olefins without requiring a high-concentration aqueous solution of hydrogen peroxide and further without adding an additive such as formaldehyde. Therefore, it is preferable.

Here, specific examples of the platinum group metal include rhodium, iridium, platinum, palladium and the like, preferably palladium. The platinum group metal may be used as it is or may be used by being supported on various carriers such as activated carbon. Various types of such supported platinum group metals are commercially available.

The form of the platinum group metal may be any form such as fine powder, pellets, etc. The reaction may be either a continuous type or a batch type, and the reaction apparatus may be a suspension bed type, fixed bed type or the like. . These are not particularly limited. The amount of the platinum group metal used is not particularly limited, but in the case of a suspension bed type, usually 1 mg per 100 ml of the reaction medium.
It is carried out in an amount of 10 to 10 g, preferably 10 to 10 g.

The acids mentioned here are sulfuric acid, hydrochloric acid,
Phosphoric acid or the like can be used. It is also possible to use a mixture of these acids. Acid concentration 0.001
It is usually carried out at 1N, preferably 0.01-1N.

Specific examples of the alkali metal or alkaline earth metal halide include sodium fluoride, sodium chloride, sodium bromide, sodium iodide, potassium chloride, potassium bromide, magnesium chloride, and the like.
Examples include magnesium bromide, calcium chloride, calcium bromide and the like. Preferably, an alkali metal chloride, bromide or iodide is used, and more preferably an alkali metal chloride or bromide. Most preferred is an alkali metal bromide. The amount of alkali metal or alkaline earth metal halide used is
Usually 1 × 10 ⁻⁶ to 1 × 10 ⁻³ N, preferably 1 × 10 ⁻⁶ N.
It is carried out at 10 ^-5 to 1 × 10 ^-3 N.

Hydrogen peroxide produced by catalytically reacting hydrogen and oxygen in an alcoholic medium containing an acid and an alkali metal or alkaline earth metal halide in the presence of such a platinum group metal is It is preferable to carry out a neutralization treatment with a base before use in the following olefin epoxide production step, since the selectivity of the epoxide becomes high. As such a base, a hydroxide solution of an alkali metal or an alkaline earth metal is preferable, and specific examples thereof include sodium hydroxide, potassium hydroxide, calcium hydroxide, and rubidium hydroxide. A hydroxide is used. These bases are usually used in an aqueous solution or an alcohol solution, and a high-concentration solution of, for example, 1 to 20 N is preferable so as not to remarkably lower the concentration of hydrogen peroxide after the neutralization treatment. The amount of the base is preferably as close to the equivalence point as possible.

In the reaction for producing hydrogen peroxide in the present invention, the partial pressure ratio between oxygen and hydrogen is usually from 1:50 to 50: 1.
It can be carried out within the range. It is possible to carry out the reaction by diluting with an inert gas, or to carry out the reaction using air instead of oxygen. For safety reasons, it is preferable to carry out the reaction outside the explosion range. The reaction is generally carried out at a temperature in the range from 5C to 60C, preferably from 10C to 50C. The reaction pressure is not particularly limited, but is from atmospheric pressure to 150 kg / cm ^2.
G, especially in the range of 5 to 50 kg / cm ² · G.

In the present invention, the thus obtained solution of hydrogen peroxide in an alcoholic medium is used in the next step of producing an epoxidized olefin.
Usually, the solid components in the reaction medium are removed before use in the next step. The method for removing the solid component is not particularly limited, and may be performed by an appropriate method such as decantation or filtration.

(2) Epoxidation of olefins The catalyst used in the present invention for the synthesis of propylene oxide is M
oO ₃ , V ₂ O ₅ , WO ₃ , titanosilicate and SiO
_Although TiO ₂ supported on a carrier such as ₂ can be used, titanosilicate is preferred. The titanosilicate referred to here is crystalline S having a zeolite structure.
It is obtained by substituting a part of silicon forming a crystal lattice of iO ₂ with titanium. The present invention is not particularly limited to a method for synthesizing titanosilicate, but examples of the synthesis include JP-A-56-97720. Si / Ti in titanosilicate
The atomic ratio of 10 to 1000 is used.

In the present invention, the amount of the oxidation catalyst to be used is not particularly limited.
It is used in the range of 1 mg to 10 g per 00 ml. The catalyst may be in any form such as a fine powder or pellets, and the reaction may be a continuous system or a batch system. The reaction apparatus may be a suspension bed system, a fixed bed system, or the like. These are not particularly limited.

The olefins epoxidized by the method of the present invention include, for example, ethylene, propylene, allyl chloride, 2-butene, 1-octene, 1-tridecene, mesityl oxide, isoprene, cyclooctene, and cyclohexene. . Preferred are ethylene and propylene, and more preferred is propylene.

The reaction temperature is 5 ° C. to 150 ° C., preferably 3 ° C.
The reaction is generally carried out at a temperature in the range of 0 ° C to 100 ° C. However, when the reaction is carried out at a temperature higher than the boiling point of the medium, it is necessary to carry out the reaction under pressure. When a gaseous olefin is used, the reaction pressure is not particularly limited, but is from atmospheric pressure to 100 kg / cm.
It is carried out in the range of ² · G, especially 3 to 30 kg / cm ² · G.

[0030]

The present invention will be described in more detail with reference to examples and comparative examples, but the present invention is not limited to these examples.

The hydrogen peroxide concentration in the examples was determined by an iodine titration method. For the titration, an automatic potentiometer AT-310 manufactured by Kyoto Electronics Industry Co., Ltd. was used.

The epoxidation reaction product was quantified using a gas chromatograph, and the selectivity for propylene oxide was calculated from the following equation. (Selectivity% of propylene oxide) = (moles of propylene oxide produced) / (moles of hydrogen peroxide consumed) × 100

The conversion of hydrogen peroxide was calculated from the following equation. (Conversion rate of hydrogen peroxide) = (moles of hydrogen peroxide consumed) / (moles of hydrogen peroxide before reaction) × 100

The specific surface area was measured using Flowsorb II 2300 manufactured by Micromeritics.

Example 1 (1) Production of hydrogen peroxide PdBr ₂ (manufactured by Nacalai Tesque, Inc .;
4 m ² / g) A 300 ml glass inner cylinder charged with 30 mg and 120 ml of methanol was placed in an inner volume of 400 m.
1 autoclave. 80 ml / min of hydrogen gas and 800 ml / min of oxygen gas by gas injection tube
min. 2500 m of nitrogen gas in the gas phase
1 / min, the internal pressure of the autoclave is 9kg / c
The pressure was maintained at m ² · G and the reactor was kept at 20 ° C. with external cooling. Two hours after the start of the reaction, the concentration of hydrogen peroxide in the reaction solution was 0.15 wt%.

(2) Production of Propylene Oxide 48 g of the methanol solution of hydrogen peroxide obtained in (1) and 200 mg of titanosilicate (manufactured by NE Chemcat, Inc .: Si / Ti atomic ratio: 50) are contained in an internal volume of 125
propylene gas in a 4 ml autoclave
g / cm ² · G. Reaction temperature 40 ° C
After stirring for 1 hour, the conversion of hydrogen peroxide was 99% and the selectivity for propylene oxide was 70%.

Example 2 (1) Production of hydrogen peroxide 30 mg of Pd powder (manufactured by Tanaka Kikinzoku International; specific surface area: 10.8 m ² / g) and 0.0012 N-Na
A 300 ml glass inner cylinder charged with a mixed methanol solution of 5 ml of a Br methanol solution, 5 ml of a 1.2 N—H ₂ SO ₄ methanol solution, and 110 ml of methanol,
It was mounted in an autoclave having an internal volume of 400 ml. Hydrogen gas and oxygen gas were introduced at 80 ml / min and 800 ml / min, respectively, through a gas injection tube. For safety, nitrogen gas was introduced and diluted into the gas phase at 2500 ml / min. The pressure was maintained such that the internal pressure of the autoclave became 9 kg / cm ² · G, and the reactor was kept at 20 ° C. by external cooling. Two hours after the start of the reaction, the concentration of hydrogen peroxide in the reaction solution was 0.35% by weight.

(2) Production of propylene oxide 2N-N is added to the methanol solution of hydrogen peroxide obtained in (1).
48 g of a stirred solution containing 3.1 ml of an aOH aqueous solution
Then, 200 mg of titanosilicate (manufactured by NE Chemcat Corporation: Si / Ti atomic ratio: 50) was charged into an autoclave having an internal volume of 125 ml, and propylene gas was injected into the autoclave so that the pressure became 4 kg / cm ² · G. After stirring at a reaction temperature of 40 ° C. for 1 hour, the conversion of hydrogen peroxide was 65%, and the selectivity of propylene oxide was 95%.
Met.

Example 3 Example 2 (2) was prepared by using a solution obtained by stirring 2.5 ml of a 2N aqueous solution of NaOH in a methanol solution of hydrogen peroxide obtained under the same conditions as in Example 2 (1). The reaction was performed under the same conditions as described above. One hour after the start of the reaction, the conversion of hydrogen peroxide was 98%, and the selectivity for propylene oxide was 27%.

[0040]

According to the present invention, an inexpensive low-concentration hydrogen peroxide which does not need to be concentrated can be effectively used without requiring a high-concentration aqueous solution of hydrogen peroxide, and epoxidation proceeds with high selectivity. I do. As a result, epoxidized olefins, for example, propylene oxide, can be produced at low cost without co-producing large amounts of by-products.

──────────────────────────────────────────────────続 き Continuation of the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical indication // C07B 61/00 300 C07B 61/00 300 (72) Inventor Toshio Sasaki 6 Kitahara, Tsukuba, Ibaraki Prefecture Sumitomo Chemical Co., Ltd.

Claims (14)

[Claims] An olefin characterized in that an olefin is oxidized in the presence of an oxidation catalyst using a solution of hydrogen peroxide in an alcoholic medium produced by catalytically reacting hydrogen and oxygen in an alcoholic medium. For the production of epoxides of the class. 2. The method for producing an epoxidized olefin according to claim 1, wherein the oxidation catalyst is titanosilicate. 3. The method for producing an epoxidized olefin according to claim 1, wherein the olefin is propylene. 4. An alcoholic solution of hydrogen peroxide produced by contacting hydrogen and oxygen in an alcoholic medium in the presence of a platinum group metal or a compound of a platinum group metal in an alcoholic medium solution of hydrogen peroxide. The method for producing an epoxidized olefin according to any one of claims 1 to 3, wherein the olefin is an aqueous medium solution. 5. An alcoholic medium solution of hydrogen peroxide produced by contacting hydrogen and oxygen in an alcoholic medium in the presence of a halogen compound of a platinum group metal in an alcoholic medium solution of hydrogen peroxide. The method for producing an epoxidized olefin according to any one of claims 1 to 3, wherein 6. The process for producing an epoxidized olefin according to claim 5, wherein the halogen compound of a platinum group metal is supported on a carrier. 7. The process for producing an epoxidized olefin according to claim 5, wherein the halogen compound of the platinum group metal is a halogen compound of palladium or platinum. 8. The method according to claim 5, wherein the halogen compound of the platinum group metal is palladium chloride or palladium bromide. 9. An alcoholic medium solution of hydrogen peroxide comprising catalytically reacting hydrogen and oxygen in an alcoholic medium containing an acid and a halide of an alkali metal or alkaline earth metal in the presence of a platinum group metal. The method for producing an epoxidized olefin according to any one of claims 1 to 3, wherein the method is an alcoholic medium solution of hydrogen peroxide produced by the reaction. 10. An alcoholic medium solution of hydrogen peroxide,
An acid in the presence of a platinum group metal and an alcoholic medium solution of hydrogen peroxide produced by catalytically reacting hydrogen and oxygen in an alcoholic medium containing an alkali metal or alkaline earth metal halide, The method for producing an epoxidized olefin according to any one of claims 1 to 3, wherein the solution is a solution subjected to a neutralization treatment with a base. 11. The process for producing an epoxidized olefin according to claim 9, wherein the platinum group metal is supported on a carrier. 12. The method for producing an epoxidized olefin according to claim 9, wherein the platinum group metal is palladium. 13. The method according to claim 10, wherein the base is a hydroxide solution of an alkali metal or an alkaline earth metal. 14. The process for producing an epoxidized olefin according to claim 1, wherein the alcoholic medium is methanol.