JPH1110009A - Method for recovering carbonylation catalyst - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently separate and recover catalytic components from a carbonylation reaction product. SOLUTION: The carbonylation reaction product containing the catalyst consisting of a group VIII metal source A in periodic Table such as a platinum compound and an organic phosphorus such as triphenyl phosphine, arsenic or an antimony compound B is extracted by at least one kind of a solvent D selected from an aliphatic hydrocarbon such as hexane, an alicyclic hydrocarbon such as cyclohexane and the like in the coexistence of an α,β-unsaturated carbonic acid C and the catalyst is recovered from the raffinate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for recovering a carbonylation catalyst useful for carbonylation of an acetylenic or olefinically unsaturated compound.

[0002]

2. Description of the Related Art Group VIII metal compounds and organic phosphorus,
A carbonylation method has been proposed in which an acetylenic or olefinically unsaturated compound is reacted with carbon monoxide and a nucleophilic compound in the presence of a carbonylation catalyst composed of an arsenic or antimony compound. For example, European Patent Application Publications EP-A1-106379, EP-A1-2
35864, EP-A1-274795, EP-A1-
279777 discloses a method of carbonylating an olefinic and acetylenically unsaturated compound in the presence of a carbonylation catalyst comprising a palladium compound, a triarylphosphine and a protonic acid. Tokuhei 5-
No. 29212, JP-A-61-176549,
JP-A-62-72649, JP-A-63-1546
No. 46 discloses a method of carbonylating an olefinic and acetylenically unsaturated compound in the presence of a carbonylation catalyst composed of a divalent palladium compound, an organic phosphine and a protonic acid. Further, JP-A-4-215581 discloses a carbonylation catalyst system composed of a proton source and an alkylsulfonic acid anion source, and a method of carbonylating an olefinic and acetylenic unsaturated compound using the catalyst system. It has been disclosed. Japanese Patent Application Laid-Open No. 4-215852 discloses an olefin system and a tertiary amine using a catalyst system containing a metal source of a Group VIII metal of the periodic table, a phosphine having an imino nitrogen atom-containing aromatic substituent, a proton source and a tertiary amine. A method for carbonylation with an acetylenically unsaturated compound is disclosed. JP-A-4-215581 and JP-A-4-21585
No. 2 describes that a palladium compound is preferable as a metal source of Group VIII metal of the periodic table.

According to these methods, for example, methacrylic acid esters can be obtained from methylacetylene, carbon monoxide and alcohol. Therefore, as compared with a method for producing a methacrylate by the acetone cyanohydrin method using a large amount of sulfuric acid, there is an advantage that a methacrylate or the like can be produced without generating waste such as waste sulfuric acid. However, when the carbonylation reaction is performed in the catalyst system used in the above method, and the catalyst solution obtained by distilling and separating the product is reused in the reaction system, high-boiling by-products that cannot be separated by distillation accumulate in the catalyst solution. Then, the concentration of the catalyst gradually decreases, and finally the operation has to be stopped.
This high-boiling by-product is composed of a polymer of an olefin-based and acetylene-based unsaturated compound as a raw material,
Extremely high boiling point. Therefore, when a high-boiling by-product is separated from the catalyst solution by distillation, the expensive catalyst is exposed to high temperatures to be altered. Therefore, in order to avoid deterioration of the catalyst due to heating, a method of extracting high-boiling by-products accumulated in the catalyst solution by extraction may be considered. However, simply adding the extraction solvent to the catalyst solution does not cause phase separation,
High boiling by-products and catalyst components cannot be separated.

On the other hand, JP-B-53-3993 and JP-B-53-3994 disclose that a catalyst solution containing a Group VIII noble metal complex is treated with activated carbon in the presence of methanol.
A method has been proposed in which the group VIII noble metal complex is adsorbed on activated carbon and recovered. However, in this method, it is necessary to use about 10 times the volume of methanol with respect to 1 volume of the catalyst solution, and the methanol recovery cost cannot be ignored. In addition, the time and effort for filtration and recovery of the activated carbon to which the metal complex has been adsorbed is large. Further, the Group VIII noble metal is recovered as a metal instead of a complex having high catalytic activity by burning activated carbon to which the metal complex is adsorbed. Requires a process. Also,
In this method, another catalyst component such as an organic phosphorus compound cannot be recovered. Japanese Patent Publication No. 53-5879 proposes a method of burning a catalyst solution containing a Group VIII noble metal complex and introducing a combustion product into an absorbing solution to recover a Group VIII noble metal. However, also in this method, what is recovered is a metal, not a highly active metal complex. Therefore, it is necessary to convert the recovered metal into a metal complex through many steps. In addition, organic phosphorus compounds and the like cannot be recovered.

[0005]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a method for recovering a carbonylation catalyst which can efficiently separate and recover a catalyst component from a carbonylation reaction product. Another object of the present invention is to provide a method for recovering a carbonylation catalyst that can recover a catalyst component from a carbonylation reaction product while suppressing deterioration. It is still another object of the present invention to provide a method for recovering a carbonylation catalyst which can recover a catalyst component of the Group VIII metal compound as a catalyst component in a highly active form from a carbonylation reaction product. Another object of the present invention is to provide a method for recovering a carbonylation catalyst which can easily recover not only a Group VIII metal compound of the periodic table but also an organic phosphorus, arsenic or antimony compound from a carbonylation reaction product. .

[0006]

Means for Solving the Problems The present inventors have made intensive studies to achieve the above object, and as a result, when a carbonylation reaction product is extracted with a specific extraction solvent in the presence of a specific compound, the carbonylation reaction product is obtained. The present inventors have found that the high-boiling by-product and the catalyst component contained in the reaction product are efficiently distributed to the extractant phase and the raffinate phase, respectively, and completed the present invention. That is, the present invention relates to a method for recovering a catalyst from a carbonylation reaction product containing a catalyst composed of a metal source of a Group VIII metal of the periodic table (A) and an organic phosphorus, arsenic or antimony compound (B). The carbonylation reaction product is extracted with at least one solvent (D) selected from aliphatic hydrocarbons and alicyclic hydrocarbons in the presence of α, β-unsaturated carboxylic acid (C). And a method for recovering the carbonylation catalyst from the raffinate phase. Periodic Table No.
Group VIII metals include iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, platinum and the like. Organic phosphorus, arsenic or antimony compound (B)
For example, a third organic phosphine can be used. α, β
The unsaturated carboxylic acid (C) includes, for example, a compound represented by the general formula (1) C (R ^a ) (R ^b ) = C (R ^c ) -COOH (1) (where R ^a , R ^b , R ^c Is the same or different and represents a hydrogen atom or an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group or an aryl group which may have a substituent. Derivatives are included. As the solvent (D), C
At least one compound selected from _4-14 aliphatic hydrocarbons and C _5-10 alicyclic hydrocarbon can be used.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION

[Carbonylation reaction product] The carbonylation reaction product used in the method of the present invention is a catalyst comprising a metal source of Group VIII of the periodic table (A) and an organic phosphorus, arsenic or antimony compound (B). Any reaction product can be used as long as it is obtained by carbonylation of a substrate using The reaction product includes not only the reaction mixture after the carbonylation reaction (reaction mixture), but also a treated product obtained by subjecting the reaction mixture to an appropriate physical or chemical treatment (for example, concentration, distillation, filtration, etc.). The target solution, unreacted components, low-boiling by-products, reaction solvent, treatment liquid after removal of precipitates, etc. by the separation means are also included. A typical example of the carbonylation reaction is a reaction between an acetylenically unsaturated compound or an olefinically unsaturated compound and carbon monoxide.

The Group VIII metal elements of the periodic table include, for example,
Includes iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium and platinum. 199
From year 0 onward, the element has been replaced by Group VIII element of the periodic table (F
e, Ru, Os), Group 9 elements (Co, Rh, Ir),
It is classified as a Group 10 element (Ni, Pt). Preferred elements include rhodium, cobalt, nickel, palladium and platinum. The oxidation number of the element can be selected according to the type and is not limited. The oxidation number is 0, +2,
+3, +4, etc. in many cases. The group VIII metal source (A) of the periodic table may be a simple metal, but is preferably a compound of a group VIII element of the periodic table. Compounds of Group VIII elements of the periodic table include, for example, inorganic acid salts (e.g., nitrate, sulfate, perhalate, hydrohalic acid such as hydrochloric acid, hydrobromic acid, etc.), and organic acid salts (For example, methanesulfonic acid, ethanesulfonic acid, benzenesulfonic acid,
Sulfonates such as p-toluenesulfonic acid; Phosphonates; 1 to 12 carbon atoms such as formic acid, acetic acid and propionic acid
Carboxylate, etc.), halides (eg, chloride, bromide, etc.), complexes (or complex salts), and the like.

The ligand constituting the complex is, for example, OH
(Hydroxo), alkoxy groups such as methoxy, ethoxy, propoxy, butoxy groups, acyl groups such as acetyl and propionyl, alkoxycarbonyl groups such as methoxycarbonyl (acetato) and ethoxycarbonyl, acetylacetonato, cyclopentadienyl group, benzylidene Groups, cycloalkadiene such as benzylidene acetone, benzylidene acetylacetone, benzylidene acetophenone, cyclooctadiene, halogen atom such as chlorine and bromine, CO, CN, oxygen atom, H ₂ O (aquo), phosphine (for example, triphenylphosphine and the like) Triarylphosphine), NH ₃ (ammine),
Nitrogen-containing compounds such as NO, NO ₂ (nitro), NO ₃ (nitrat), ethylenediamine, diethylenetriamine, pyridine, and phenanthroline are included. In the complex or complex salt, the same or different ligands may be coordinated by one kind or two or more kinds.

Examples of the complex or complex salt include acetylacetone palladium, tetrakis (triphenylphosphine) palladium, bis (tri-o-tolylphosphine) palladium acetate, bis (diphenyl-2-pyridylphosphine) palladium acetate, and tetrakis (diphenyl-palladium). 2-pyridylphosphine) palladium,
Palladium complexes or complex salts such as bis (di-o-tolylpyridylphosphine) palladium acetate and bis (diphenylpyridylphosphine) palladium sulfate; dibenzylidene ketone platinum such as dibenzylideneacetone platinum, dibenzylideneacetylacetone platinum and dibenzylideneacetophenone platinum; Cyclooctadiene platinum, dichlorobis (trifluorophosphine) platinum,
Platinum complexes or complex salts of tetrakis (triphenylphosphine) platinum, bis (triphenylphosphine) platinum acetate, bis (triphenylphosphine) platinum sulfate, hexachloroplatinic (IV) acid, and the like; An example is a complex or complex salt of an element.

The amount of the Group VIII metal source (A) used in the periodic table is as follows:
Although it depends on the type of the substrate used, for example, 1 × 10 ⁻⁶ to 2 × as the metal atom of the Group VIII metal source in the periodic table per 1 mol of the substrate (for example, an acetylenic or olefinically unsaturated compound). 10 ^-1 mol, preferably 1 ×
About 10 ^-5 to 1 × 10 ^-1 mol, and 1 × 10 ^-4 to 1 ×
It is often about 10 ^-2 mol.

The organic phosphorus, arsenic or antimony compound (B) may contain at least one phosphorus, arsenic or antimony atom.
Coordination is often possible with Group VIII elements. These compounds are often different from the ligands constituting the metal compounds (complexes) of the group VIII of the periodic table. These compounds are used alone or in combination of two or more.

The compound (B) includes a compound represented by the following formula.

[0014]

Embedded image (Wherein, A represents a phosphorus atom, an arsenic atom or an antimony atom, and R ¹ , R ² and R ³ are the same or different and represent a hydrogen atom, an alkyl group which may have a substituent, An alkenyl group which may have, an alkynyl group which may have a substituent, a cycloalkyl group which may have a substituent or an aryl group which may have a substituent,
A heterocyclic group which may have a substituent is shown. R ² and R ³
May combine with each other to form an alkylene group which may have a substituent. However, R ^{1 to} R ³ are not hydrogen atoms at the same time. In the above formula, examples of the alkyl group include methyl, ethyl, propyl, isopropyl, butyl, isobutyl,
1 to 10 carbon atoms such as s-butyl, t-butyl, pentyl, hexyl, heptyl, octyl, nonyl, and decyl groups
A straight or branched chain alkyl group is included. Preferred alkyl groups include, for example, lower alkyl groups having about 1 to 6 carbon atoms, particularly about 1 to 4 carbon atoms.

Alkenyl groups include, for example, vinyl, allyl, isopropenyl, 2-methyl-1-propenyl,
-Includes a linear or branched alkenyl group having about 2 to 10 carbon atoms, such as -butenyl, 2-butenyl, 1-pentenyl, 1-hexenyl, 1-heptenyl, 1-octenyl, 1-nonenyl, and 1-decenyl. It is. Preferred alkenyl groups include, for example, alkenyl groups having 2 to 6 carbon atoms, particularly about 2 to 4 carbon atoms.

Examples of the alkynyl group include those having 2 carbon atoms such as ethynyl, propynyl, 1-butynyl, 2-butynyl, 1-pentynyl, 1-hexynyl, 1-heptynyl, 1-octynyl, 1-noninyl and 1-decynyl. -10
Alkynyl groups. The cycloalkyl group includes, for example, a cycloalkyl group having about 4 to 10 carbon atoms such as a cyclobutyl, cyclopentyl, cyclohexyl, and cyclooctyl group, and the aryl group includes a phenyl group, a naphthyl group, and the like.

The heterocyclic group includes a heterocyclic group containing a nitrogen atom as a hetero atom, in particular, an aromatic heterocyclic group. Such heterocyclic groups include, for example, pyridyl such as 2-pyridyl, pyrazinyl such as 2-pyrazinyl, quinolyl such as 2-quinolyl, isoquinolyl such as 1-isoquinolyl, pyrimidinyl such as 2-pyrimidinyl, 3-pyridazinyl and the like. Pyridazinyl, cinnolinyl, triazinyl, quinoxalinyl, quinazolinyl and the like.
Preferred heterocyclic groups include pyridyl, pyrimidinyl and the like.

These alkyl group, alkenyl group, alkynyl group, cycloalkyl group, aryl group and heterocyclic group include various substituents which do not impair the catalytic activity, for example, halogen atom, alkyl group, hydroxyl group, alkoxy group and the like. Group,
Carboxyl group, alkoxycarbonyl group, acyl group,
A nitro group, a cyano group and the like may be substituted.

In the above formula, A is preferably a phosphorus atom or an arsenic atom, and particularly preferably a phosphorus atom.
R ^{1 to} R ³ are often an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, or an aryl group which may have a substituent. Particularly preferred organic phosphine has at least one substituent among R ^{1 to} R ³ is composed of an aryl group such as a phenyl group or a substituted fer group. Further, instead of the aryl group or together with the aryl group, a heterocyclic group or an alkylene group formed by a bond between R ² and R ³ is also preferable.

Preferred compounds (B) include organic phosphine, organic arsine, organic stibine and the like. The organic phosphine may be any of the first phosphine, the second phosphine, and the third phosphine. In addition, organic arsine and organic stibine are also first to third arsine and first to third.
Any of the third stibins may be used.

Examples of the first phosphine include methyl phosphine, ethyl phosphine, isopropyl phosphine, phenyl phosphine, cyclohexyl phosphine and the like. Examples of the second phosphine include dimethyl phosphine, diethyl phosphine, diisopropyl phosphine, diphenyl phosphine, dicyclohexyl phosphine, and the like. As the third phosphine, for example, triphenylphosphine, tri (4-methylphenyl) phosphine, tri (3,5-dimethylphenyl) phosphine, tri (2,4,6-trimethylphenyl) phosphine, tri (4-methoxy) Optionally substituted triarylphosphines such as phenyl) phosphine, tri (3,5-dimethoxyphenyl) phosphine, tri (4-chlorophenyl) phosphine, tri (3,5-dichlorophenyl) phosphine; methyldiphenylphosphine , ethyl diphenyl phosphine, mono C _1-10 alkyl diaryl phosphines such as butyl diphenylphosphine, dimethylphenyl phosphine, di C _1-10 monoaryl phosphines such as dibutyl triphenylphosphine; trimethylphosphine, triamyl Cyclopentyl diphenylphosphine, mono C _4-10 cycloalkyl diaryl phosphines such as cyclohexyl diphenylphosphine; tri C _1-10 alkyl phosphine such as phosphine dicyclopentyl triphenylphosphine, di-C, such as dicyclohexyl phenylphosphine
_4-10 cycloalkyl monoaryl phosphine; tri-C _4-10 cycloalkyl phosphine such as tricyclopentyl phosphine and tricyclohexyl phosphine; 2-pyridylbisphenylphosphine, bis (2-pyridyl) phenylphosphine, tris (2-pyridyl) phosphine , 2-pyridylbismethylphosphine, 6-methyl-
2-pyridylbisphenylphosphine, 6-methoxy-
2-pyridylbisphenylphosphine, 6-chloro-2
-Pyridylbisphenylphosphine, 2,6-bis (diphenylphosphino) pyridine, 2,6-bis (di-p
Phosphines having a heterocyclic group such as-(tolylphosphino) pyridine; ethane-1,2-diylbisdiphenylphosphine, ethene-1,2-diylbisdiphenylphosphine, ethyne-1,2-disylbisdiphenylphosphine, 1,2- Phenylenebisdiphenylphosphine,
Hexafluorocyclopentene-1,2-diylbisdiphenylphosphine, 1,4-diphenyl-1,4-diphosphacyclohexane, bis (1,2-diphenyl)
Examples include phosphinomethylcyclobutane. First
Examples of the first to third arsines and the first to third stibines include compounds corresponding to the first to third phosphines.
Among these compounds, third phosphine, third arsine, third stibine and the like are preferable.

The amount of the organic phosphorus, arsenic or antimony compound (B) used is, for example, 0.1 to 1000 mol, preferably 0.5 to 500 mol, per 1 mol of the group VIII metal source (A) in the periodic table. Mole, more preferably 1-100
Mole, and often about 1 to 50 mole.

In the carbonylation reaction, in addition to the group VIII metal source (A) and the organic phosphorus, arsenic or antimony compound (B), a third catalyst component
Acids and / or electron donating compounds may be used. The acids include various protic acids (inorganic and organic) and Lewis acids. Protic acids include, for example, sulfuric acid, hydrohalic acid, nitric acid, phosphoric acid, sulfonic acid (arylsulfonic acid, alkylsulfonic acid, etc.),
Examples include phosphonic acids, carboxylic acids (such as formic acid, acetic acid, and propionic acid), perhalic acids, and heteropoly acids. One or more of these acids are used. The ratio of the acid (protic acid or the like as a proton source) is, for example, 0.1 to 1 with respect to 1 mol of the Group VIII metal source (A) in the periodic table.
000 mol, preferably 1 to 500 mol, more preferably about 5 to 250 mol, and often about 1 to 100 mol.

The electron donating compound includes an electron donating degree
Compounds having νD of 2 or more are used. The electron donation degree △
νD is the O- value of deuterated methanol (0.4 mol / L) added to the liquid compound using benzene as a reference substance.
Wave number of D non-associative stretching vibration (2400-2700c
m ^-1 ), and is defined as “electron donability to methanol D △ νD”. The electron donating compound seems to have a coordination property with respect to the Group VIII element of the periodic table. Such electron donating compounds include, for example, amines (triethylamine, N,
N-dimethylaniline, triethanolamine, piperidine, etc.), basic nitrogen-containing heterocyclic compounds (pyridine,
Imines (e.g., imidazole), imines (e.g., N-phenylethyleneimine), amides (acetamide, N, N-dimethylformamide), sulfoxides (e.g., dimethyl sulfoxide), aldehydes (e.g., n-butyraldehyde), ethers (diethyl) Ether, ethylene glycol dimethyl ether, anisole, tetrahydrofuran, 1,4-dioxane, etc.), ketones (acetone,
Methyl ethyl ketone, cyclohexanone, etc.), lactones (γ-butyrolactone, etc.), esters (ethyl acetate, methyl methacrylate, etc.), nitriles (acetonitrile, benzonitrile, etc.), nitro compounds (nitrobenzene, etc.), aromatic hydrocarbons ( Toluene, xylene, etc.), aliphatic hydrocarbons (ethylene chloride, etc.) and the like. These electron donating compounds are used alone or in combination of two or more. The amount of the electron donating compound is
1 to 100,000 per 1 mol of the Group VIII metal source
Mol, preferably about 5 to 50,000 mol, more preferably about 10 to 10,000 mol. The electron-donating compound can be used as a reaction solvent. In this case, the amount of the electron-donating compound used may be an excess with respect to 1 mol of the Group VIII metal source.

As a substrate for the carbonylation reaction, an acetylenic or olefinically unsaturated compound is often used. Among them, asymmetric acetylene compounds or olefin compounds, more preferably α-acetylene compounds, α-olefin compounds or allene compounds are used. The number of carbon atoms of the acetylene-based unsaturated compound is usually about 2 to 30, preferably 2 to 20, particularly 2 to 2.
The number of carbon atoms of the olefinically unsaturated compound and the allene compound is, for example, 2 to 30, preferably 2 to 30.
20, especially about 2 to 10. These unsaturated hydrocarbons include optionally substituted alkynes, alkenes (olefins), cycloalkenes, cycloalkadienes and bridged unsaturated hydrocarbons. The unsaturated hydrocarbon may have a triple bond and a double bond in one molecule, or may have two or more double bonds.

Examples of the alkyne include acetylene,
Propyne, 1-butyne, 2-butyne, 1-pentyne, 1
-Hexin, 1-heptin, 1-octin, 2-octyne, 4-octyne and the like. Alkenes include, for example, ethylene, propylene, phenylethylene, 1-
Butene, 2-butene, 1-pentene, 3-methylpentene-1, 1-hexene, 1-heptene, 1-octene,
2-octene, 4-octene, arene, cyclohexene, norbornadiene and the like are included.

The unsaturated compound is often carbonylated in the presence of another reactant (eg, a nucleophilic compound having hydrogen or a removable hydrogen atom). The nucleophilic compound having a removable hydrogen atom includes a compound having a hydroxyl group such as alcohols, water, and carboxylic acid. The alcohols also include silanols.

Alcohols include aliphatic, alicyclic,
Aromatic alcohols and phenols may be used, and monohydric or polyhydric alcohols may be used. Examples of the monohydric alcohols include aliphatic alcohols such as methanol, ethanol, 2-propanol, 1-butanol, allyl alcohol, and propargyl alcohol; alicyclic alcohols such as cyclopentanol and cyclohexanol; benzyl alcohol, phenethyl alcohol And aromatic alcohols. Phenols include phenol, alkylphenol, resorcinol and the like. Polyhydric alcohols include, for example, ethylene glycol, propylene glycol, trimethylene glycol,
Glycerol and the like. Preferred alcohols include monohydric alcohols having about 1 to 20 carbon atoms, particularly about 1 to 10 carbon atoms. As the alcohols, aliphatic saturated alcohols are often used.

As the carboxylic acid, for example, formic acid,
Acetic acid, aliphatic carboxylic acids such as propionic acid, alicyclic carboxylic acids such as cyclohexane carboxylic acid, benzoic acid,
Examples thereof include aromatic carboxylic acids such as phthalic acid. The carboxylic acid is an aliphatic carboxylic acid, preferably having 2 to 2 carbon atoms.
It is often an aliphatic carboxylic acid having about 20, particularly about 2 to 10 carbon atoms.

In the carbonylation reaction, a compound corresponding to a substrate (for example, an olefinic or acetylenic unsaturated compound) is produced depending on the type of the reactant. For example, when water is used as the reactant, an unsaturated carboxylic acid such as a carboxylic acid and an α, β-unsaturated carboxylic acid corresponding to the olefinically unsaturated compound and the acetylenically unsaturated compound is formed by a carbonylation reaction. Is generated. When an alcohol is used as a reactant, an ester corresponding to the carboxylic acid and the unsaturated carboxylic acid is formed. Further, when a carboxylic acid is used as a reactant, an acid anhydride corresponding to the carboxylic acid and the unsaturated carboxylic acid is generated.

More specifically, when ethylene is used as the olefinically unsaturated compound and methanol or water is used as the reactant, methyl propionate or propionic acid is produced by the reaction with carbon monoxide. When allene is used as the olefinically unsaturated compound and methanol or water is used as a reactant, methyl methacrylate or methacrylic acid is generated by a reaction with carbon monoxide. Also, when propyne is used as the acetylenic unsaturated compound and methanol or water is used as the reactant, methyl methacrylate or methacrylic acid is generated by the reaction with carbon monoxide.

The proportion of each component in the carbonylation reaction is selected within a wide range. For example, the proportion of carbon monoxide is
The amount is, for example, about 0.1 to 100 mol, and preferably about 0.8 to 10 mol, per 1 mol of the substrate (for example, acetylene-based or olefin-based unsaturated compound). The amount of the reactant (the nucleophilic compound) to be used is, for example, about 0.1 to 100 mol, preferably about 0.8 to 10 mol, per 1 mol of the substrate (for example, acetylene-based or olefin-based unsaturated compound). When water is used as the reactant, the amount may be about 0.5 to 10 mol per 1 mol of the unsaturated compound. The reactant can be used as a reaction solvent.

The reaction may be carried out in an inert organic solvent. As the organic solvent, for example, hexane, aliphatic hydrocarbons such as octane, alicyclic hydrocarbons such as cyclohexane, aromatic hydrocarbons such as benzene, chloroform, dichloromethane, carbon tetrachloride, halogenated hydrocarbons such as chlorobenzene, These include mixed solvents.

The carbonylation reaction is, for example, 10 to 25.
0 ° C (for example, 10 to 200 ° C), preferably 25 to 20 ° C
The reaction is performed at a temperature of about 0 ° C. and a normal pressure to about 150 atm (preferably normal pressure to 100 atm, usually about 10 to 70 atm). The reaction can be performed by a conventional method such as a batch system, a semi-batch system, or a continuous system, and is performed in a liquid phase or a gas phase. The catalyst may be either homogeneous or heterogeneous.

The carbonylation reaction product obtained as described above usually contains the catalyst components (A) and (B)
In addition, a high-boiling by-product such as a polymer of an olefinic or acetylenic unsaturated compound used as a substrate is included. In the present invention, such a carbonylation reaction product is used in the presence of an α, β-unsaturated carboxylic acid (C) in the presence of at least one solvent (D) selected from aliphatic hydrocarbons and alicyclic hydrocarbons. ) To extract. According to this method, the phase is separated into two phases, an extractant phase and a raffinate phase, the high-boiling by-products move to the extractant phase side, and the catalyst components (A) and (B) move to the raffinate phase side. Therefore, the catalyst component can be efficiently recovered from the raffinate phase. Further, since there is no need to perform heating or combustion treatment, the catalyst component can be recovered in a highly active form (for example, as a complex) without deteriorating the catalyst component.

[Α, β-unsaturated carboxylic acid (C)]
As the β-unsaturated carboxylic acid (C), any carboxylic acid having an unsaturated bond, for example, a double bond at the α and β positions of the carboxyl group may be used. Preferred α, β-unsaturated carboxylic acids include 2-propenoic acid represented by the general formula (1) or a derivative thereof.

In the formula (1), examples of the alkyl group include the aforementioned linear or branched alkyl groups having about 1 to 10 carbon atoms. Preferred alkyl groups include, for example, those having 1 carbon atom.
About 6 to about 6, especially about 1 to 4 carbon atoms. The alkenyl group includes the above-mentioned linear or branched alkenyl group having about 2 to 10 carbon atoms. Preferred alkenyl groups include, for example, those having 2 to 6 carbon atoms, particularly 2 carbon atoms.
Up to about 4 alkenyl groups are included. The alkynyl group includes the alkynyl group having about 2 to 10 carbon atoms. The cycloalkyl group includes the cycloalkyl group having about 4 to 10 carbon atoms, and the aryl group includes a phenyl group, a naphthyl group, and the like.

These alkyl group, alkenyl group, alkynyl group, cycloalkyl group and aryl group include various substituents which do not adversely affect phase separation, for example, the above-mentioned halogen atom, alkyl group, hydroxyl group, alkoxy group, A carboxyl group, an alkoxycarbonyl group, an acyl group, a nitro group, a cyano group and the like may be substituted.

Preferred R ^a and R ^b include a hydrogen atom, a lower alkyl group, a phenyl group and the like. Particularly preferred R ^a and R ^b are a hydrogen atom. Preferred R ^c includes a hydrogen atom, a lower alkyl group and the like. As R ^c , a hydrogen atom or a methyl group is particularly preferred.

As the α, β-unsaturated carboxylic acid (C),
For example, acrylic acid, methacrylic acid, 2-ethyl-2-
Propenoic acid, 2-propyl-2-propenoic acid, 2-butyl-2-propenoic acid, crotonic acid, 2-methyl-2-butenoic acid, 3-phenyl-2-propenoic acid, 3-methyl-
Examples thereof include 2-butenoic acid, 2-pentenoic acid, and 2-hexenoic acid. Among these, acrylic acid, methacrylic acid and the like are often used.

The α, β-unsaturated carboxylic acids (C) can be used alone or in combination of two or more. The α, β-unsaturated carboxylic acid (C) may be added to the reaction product after the carbonylation reaction, or may be added to the reaction system in advance. In the latter case, the α, β-unsaturated carboxylic acid (C) is advantageous because it also acts as the “acid” which is the third catalyst component in the carbonylation reaction.

The amount of the α, β-unsaturated carboxylic acid (C) to be used is usually 1 mol or more (for example, about 1 to 100 mol) per 1 mol of the organic phosphorus, arsenic or antimony compound (B). Preferably it is about 2 to 50 mol, more preferably about 5 to 30 mol. If the amount of the α, β-unsaturated carboxylic acid (C) is too small, for example, the separation efficiency of the catalyst component (B) tends to decrease, while if too large, the α, β-unsaturated carboxylic acid after extraction is too large. The operation of separating the acid (C) from the catalyst component tends to be complicated.

The α, β-unsaturated carboxylic acid (C) appears to form an ionic betaine compound with the organic phosphorus, arsenic or antimony compound (B). For example, α,
β-unsaturated carboxylic acids and organophosphorus compounds form phosphobetaine compounds. The betaine compound is easily phase-separated from an aliphatic hydrocarbon or an alicyclic hydrocarbon. on the other hand,
The Group VIII metal source (A) has an affinity for the betaine compound, and the high-boiling by-product formed by the carbonylation reaction has an affinity for the aliphatic hydrocarbon or the alicyclic hydrocarbon. For this reason, along with the phase separation, the catalyst components (A) and (B) are efficiently distributed to the raffinate phase, and the high-boiling by-products are efficiently distributed to the extractant phase.

[Extraction Solvent (D)] As the extraction solvent (D), at least one solvent selected from aliphatic hydrocarbons and alicyclic hydrocarbons can be used. Examples of the aliphatic hydrocarbon include linear or branched saturated aliphatic hydrocarbons such as butane, isobutane, pentane, isopentane, hexane, heptane, isooctane, octane, decane, dodecane, and tetradecane; 1-butene, 2-butene, butadiene, 3-methyl-1-butene, 1-pentene, 2-pentene, pentadiene, 1-hexene,
Linear or branched unsaturated aliphatic hydrocarbons such as octene, 1-decene, 1-dodecene, 1-butyne; cyclopentane, 1-methylcyclopentane, cyclohexane, cycloheptane, cyclooctane, cyclodecane And unsaturated alicyclic hydrocarbons such as cyclopentene, 1-methyl-1-cyclopentene, cyclohexene, cycloheptene and cyclooctene.

The extraction solvent (D) contains aliphatic hydrocarbons and alicyclic hydrocarbons as main components (for example, 50%).
% By weight or more). Such mixed liquids include petroleum products such as naphtha, gasoline, kerosene, and light oil; liquid paraffin and the like.

Preferred extraction solvents (D) include about 4 to 14 carbon atoms (preferably 4 to 14 carbon atoms) such as butane, isobutane, butadiene, pentane, isopentane, pentadiene, hexane, heptane, isooctane, octane, decane and tetradecane. About 10, more preferably,
Aliphatic hydrocarbons having about 5 to 8 carbon atoms (especially saturated aliphatic hydrocarbons); alicyclic hydrocarbons having about 5 to 10 carbon atoms such as cyclopentane and cyclohexane (especially saturated alicyclic hydrocarbons) And so on.

The amount of the extraction solvent (D) used is, for example, based on 100 parts by weight of the total amount of the carbonylation reaction product and the α, β-unsaturated carboxylic acid (C) to be subjected to the extraction.
It is about 10 to 1000 parts by weight, preferably about 50 to 500 parts by weight, and more preferably about 100 to 300 parts by weight. The extraction solvent (D) may be added to the reaction product after the carbonylation reaction, or may be added in advance to the reaction system as the reaction solvent.

In the method of the present invention, in addition to the extraction solvent (D), another solvent (E) may be used as long as the extraction efficiency is not impaired.
May be added. Such solvents include water; methanol, ethanol, 2-propanol, propanol,
Alcohols such as butanol; ketones such as acetone and methyl ethyl ketone; esters such as ethyl acetate; nitriles such as acetonitrile; ethers such as diethyl ether and tetrahydrofuran; aromatic hydrocarbons such as benzene, toluene and xylene; methylene chloride, chloroform and tetrachloride Examples thereof include halogenated hydrocarbons such as carbon and dichloroethane. These solvents can be used alone or in combination of two or more. The amount of the solvent (E) used is, for example, based on 100 parts by weight of the extraction solvent (D),
It is about 1 to 200 parts by weight, preferably about 5 to 150 parts by weight, and more preferably about 10 to 100 parts by weight. Among the above-mentioned solvents (E), when water or water and a hydrophilic solvent (for example, an alcohol such as methanol; a ketone such as acetone; a nitrile such as acetonitrile; an ether such as tetrahydrofuran) are added, the extraction of the catalyst component is caused. The partition ratio to the phase is significantly increased, and the recovery of the catalyst component can be improved. In this case, the used water shifts to the raffinate phase. Preferred hydrophilic solvents include alcohols such as methanol. When water and a hydrophilic solvent are used as the solvent (E), the ratio of the two is, for example, water / hydrophilic solvent (weight ratio) = 1/99 to 99/1, preferably 5/95 to 95.
/ 5, more preferably about 10/90 to 90/10 (particularly about 10/90 to 50/50). For example, when water and methanol are used as the solvent (E) at a ratio of water / methanol (weight ratio) = about 10/90 to 30/70, the catalyst component is almost quantitatively converted to the raffinate phase (aqueous phase). Distributed to The extraction operation can be performed by a conventional method,
Any of a batch type and a continuous type may be used. For example, an α, β-unsaturated carboxylic acid (C), an extraction solvent (D) and, if necessary, a solvent (E) are added to the carbonylation reaction product, and a conventional stirrer, a shaker or the like is used. After being mixed by the mixing means, the mixture is allowed to stand still to be separated into an extractant phase and a raffinate phase, or a carbonylation reaction product, component (C),
(D) and, if necessary, (E) are supplied to a continuous extraction device, and the obtained mixture is separated into two phases. By this extraction operation, high-boiling by-products are transferred to the extractant phase, and the catalyst components (A) and (B) are recovered in the extraction residue phase.

The raffinate phase can be recycled to the reaction system as it is or after being subjected to treatment such as concentration adjustment if necessary. Further, from the raffinate phase, a catalyst component (A),
(B) may be isolated and recycled to the reaction system. For example, a base such as sodium hydroxide or potassium hydroxide is added to the raffinate phase to release the organic phosphorus, arsenic or antimony compound (B) and to convert the α, β-unsaturated carboxylic acid (C). The catalyst component is converted into a salt corresponding to the base, extracted with water and an organic solvent, and the catalyst components (A) and (B) can be isolated from the obtained organic layer. On the other hand, the extraction solvent (D) can be recovered from the extractant phase by a conventional separation and purification means, for example, distillation.

[0050]

According to the present invention, since the carbonylation reaction product is extracted with a specific extraction solvent in the presence of a specific compound, the catalyst component can be efficiently separated and recovered from the carbonylation reaction product. In addition, Periodic Table VIII which is a catalyst component
The group metal compound can be recovered in a highly active form and without deterioration. Further, not only the Group VIII metal compound of the periodic table but also the organic phosphorus, arsenic or antimony compounds can be easily recovered.

[0051]

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

Example 1 In a reactor (an autoclave with a stainless steel electromagnetic stirring type jacket), tetrakistriphenylphosphine platinum (0) (platinum catalyst) was used as platinum metal at 2300 mg / k.
g, a catalyst solution (solvent: anisole) containing 3.5% by weight of triphenylphosphine and 18% by weight of methacrylic acid was added.
While 7.1 parts by weight and 5.4 parts by weight of propyne were continuously charged, carbon monoxide was continuously supplied so that the carbon monoxide partial pressure of the reactor gas phase became 50 atm. A heating medium was passed through the reactor jacket, and the reaction temperature was adjusted to 130 ° C. In addition, the residence time in the reactor is 60
The reaction liquid was continuously withdrawn so as to obtain the same liquid level, and the liquid level in the reactor was kept constant. The withdrawn reaction liquid was returned to normal pressure and separated into a gas component and a liquid component. The separated liquid components are charged into a distillation column (pressure: 220 mmHg, number of stages: 40 stages, reflux ratio: 1), and a low amount of unreacted methanol and a product such as methyl methacrylate is adjusted so that the amount of liquid in the system is constant. The boiling point compound was distilled off, and the catalyst solution was recovered from the bottom of the can and recycled to the reactor. Since the concentrations of platinum, triphenylphosphine, and methacrylic acid in the catalyst solution gradually decreased, they were added so as to have a constant concentration.

In this manner, methyl methacrylate was continuously produced for 500 hours. During this period, when the reaction solution was analyzed by gas chromatography, the conversion of propyne was 99.9% or more, and the selectivity for methyl methacrylate was 94%. However, the bottom temperature of the distillation column was 114 ° C. at the start of operation, but gradually increased to 125 ° C.
Became. If the operation was continued as it was, the bottom temperature of the tank further increased, and there was a concern that the catalyst components might be altered. Therefore, the operation was stopped. When the catalyst solution was analyzed, platinum 1212 mg /
kg, 3.57% by weight of triphenylphosphine, 17.83% by weight of methacrylic acid and 41% by weight of by-products. 200 parts by weight of n-hexane was added to 100 parts by weight of the catalyst solution, mixed, and allowed to stand.
The phases separated into two phases. 80% by weight of by-products are extracted into 277 parts by weight of the upper phase liquid (extractant phase), and 78% by weight of platinum and triphenylphosphine are contained in 23 parts by weight of the lower phase liquid (extracted phase). Was recovered by weight.

To the lower phase solution, methacrylic acid, triphenylphosphine and anisole were added. The platinum catalyst concentration was 2300 mg / kg as platinum metal, the triphenylphosphine concentration was 3.5% by weight, and the methacrylic acid concentration was 18% by weight. And a catalyst solution was prepared. Using this catalyst solution, the same reaction as above was performed to produce methyl methacrylate. The conversion of propyne was 99.9% or more, and the selectivity of methyl methacrylate was 94%. Similar reaction results were obtained.

Example 2 As in Example 1, 200 parts by weight of cyclohexane was added to 100 parts by weight of the catalyst solution used for the continuous reaction for 500 hours. As a result, two phases were separated. 82% by weight of by-products were extracted in 275 parts by weight of the upper phase liquid, and 80% by weight of platinum and 92% by weight of triphenylphosphine were recovered in 25 parts by weight of the lower phase liquid.

Comparative Example 1 The same operation as in Example 2 was carried out except that 200 parts by weight of toluene was used instead of 200 parts by weight of cyclohexane. As a result, the mixed solution containing the catalyst became uniform, and the catalyst component was separated and recovered. Could not.

Comparative Example 2 Mesitylene 200 was used in place of 200 parts by weight of cyclohexane.
Except for using parts by weight, the same operation as in Example 2 was performed. As a result, the mixed solution containing the catalyst became uniform, and the catalyst component could not be separated and recovered.

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁶ Identification code FI C07C 57/04 C07C 57/04 67/38 67/38 67/58 67/58 69/54 69/54 Z // C07B 61 / 00 300 C07B 61/00 300

Claims (5)

[Claims] 1. A method for recovering a catalyst from a carbonylation reaction product containing a catalyst comprising a Group VIII metal source (A) and an organic phosphorus, arsenic or antimony compound (B). The carbonylation reaction product
In the presence of α, β-unsaturated carboxylic acid (C), extraction is performed with at least one solvent (D) selected from aliphatic hydrocarbons and alicyclic hydrocarbons, and the catalyst is recovered from the raffinate phase. A method for recovering a carbonylation catalyst. 2. The group VIII metal of the periodic table is iron, cobalt,
The method for recovering a carbonylation catalyst according to claim 1, which is nickel, ruthenium, rhodium, palladium, osmium or platinum. 3. The method for recovering a carbonylation catalyst according to claim 1, wherein the organic phosphorus, arsenic or antimony compound (B) is a third organic phosphine. 4. An α, β-unsaturated carboxylic acid (C) is represented by the general formula (1): C (R ^a ) (R ^b ) = C (R ^c ) —COOH (1) (where R ^a , R ^b and R ^c are the same or different and each represent a hydrogen atom or an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group or an aryl group which may have a substituent. The method for recovering a carbonylation catalyst according to claim 1, which is -propenoic acid or a derivative thereof. 5. The recovery of the carbonylation catalyst according to claim 1, wherein the solvent (D) is at least one compound selected from C _4-14 aliphatic hydrocarbon and C _5-10 alicyclic hydrocarbon. Method.