JP2002167359A - Method for producing aromatic carbonate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a catalyst of high activity and selectivity and a method of reaction to use the above catalyst which enable to produce economically and effectively an aromatic carbonate by reacting an aromatic hydroxy compound, carbon monoxide and molecular oxygen. SOLUTION: The objective aromatic carbonate can be obtained by reacting the aromatic hydroxy compound, carbon monoxide and molecular oxygen in the presence of (a) a complex of palladium and heteropolyacid and (b) quaternary ammonium salt or quaternary phosphonate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing an aromatic carbonate by reacting an aromatic hydroxy compound with carbon monoxide and molecular oxygen using a specific catalyst.

[0002]

2. Description of the Related Art Aromatic carbonates represented by diphenyl carbonate are compounds useful as raw materials for polycarbonates. Conventionally, as a method for producing an aromatic carbonate, a method of reacting an aromatic hydroxy compound with phosgene has been used. However, the above method has many problems as an industrial production method because phosgene is highly toxic and further produces a large amount of inorganic salts as a by-product. Therefore, several methods have been proposed as a method for producing an aromatic carbonate without using phosgene.

[0003] For example, Japanese Patent Publication No. 56-38144 discloses that the periodic table IIIA, IV
A, VA, VIA, IB, IIB, IVB, VB, VI
A compound comprising a Group B, VIIB and VIIIB metal;
And a method of reacting phenol with carbon monoxide using a base. In addition, Japanese Patent Publication No. 56-3814
No. 5 discloses a method using a palladium compound and a manganese or cobalt complex, a base and a desiccant;
JP-A-165551 discloses a method using a palladium compound, an iodine compound and zeolite;
JP-A-564-564 discloses a method using a palladium compound, a manganese compound, a tetraalkylammonium salt and a quinone; JP-A-5-58961 discloses a palladium compound and cobalt, iron, cerium, manganese, molybdenum, samarium, vanadium, chromium. Using a mixture of an inorganic compound selected from copper, a co-catalyst selected from aromatic ketones, aliphatic ketones and aromatic polycyclic coal tar hydrocarbons, and a quaternary ammonium salt; In the publication, a method using a palladium compound, a cerium compound, a quaternary ammonium salt or the like;
JP-A-6-41020 discloses a method using an inorganic cocatalyst selected from a palladium compound, manganese, cobalt and copper and a nitrile compound; JP-A-6-172268 discloses a palladium compound and a five-coordinate complex of cobalt; A method using a quaternary ammonium salt or the like;
No. 2269 discloses a method using a palladium compound and an inorganic cocatalyst selected from cobalt, manganese and copper, and a quaternary ammonium salt and an organic cocatalyst such as terpyridine; JP-A-7-10812 discloses a palladium compound; JP-A-7-145107 discloses a method using a palladium compound, a manganese compound and an alkali metal halide; JP-A-8-92168 discloses a palladium compound and an alkali metal halide. JP-A 8-99935 discloses a method using a palladium compound, a lead compound, a quaternary ammonium halide salt and a copper compound;
No. 281108 discloses metals Ti, V, Mn, Cr,
Co-catalyst such as manganese or cobalt salt using a catalyst comprising a platinum group metal compound supported on a support containing oxides of Fe, Co, Ni, Cu, La, Nb, Mo, Pb, rare earth metals and actinides A reaction in the presence of a quaternary ammonium or phosphonium salt and a base; JP-A-8-281114 supports a platinum group metal compound and a metal compound acting as a cocatalyst using a known support. A method in which a reaction is carried out using a supported catalyst in the presence of a quaternary ammonium or phosphonium salt and a base; JP-A-8-283206 discloses a cocatalyst such as a platinum group metal compound, a manganese or cobalt salt, a quaternary salt and In addition to bases, methods have been proposed that additionally use heterogeneous promoters such as metal oxides, carbides, nitrides, and borides. That.

As described above, conventional catalyst systems for producing aromatic carbonates by reacting aromatic hydroxy compounds with carbon monoxide and molecular oxygen include expensive platinum group compounds such as palladium, manganese, cobalt and cerium metal compounds. In addition to the use of redox agents and the presence of co-catalysts such as quaternary ammonium salts, more expensive additives such as bases and ligands are used. Not only was separation from group carbonate difficult, but the selectivity of the reaction was not always sufficient, and purification was difficult. Further, the yield is insufficient, the reaction pressure is increased, the total pressure is relatively high, and an explosive mixed gas can be formed during the operation. Therefore, attention must be paid to its composition, and there is a safety problem.

Further, since expensive noble metals such as palladium are used, and a relatively large amount of a quaternary ammonium salt is used in addition to a redox agent, the activity and selection of the catalyst system must be high for industrial economical implementation. It is very important to be able to effectively recover and recycle the catalyst system, as well as its properties. For this purpose, there is an attempt to increase the recovery circulation property by making a part or most of the palladium catalyst system nonuniform by a method in which palladium is supported on a nonuniform support such as activated carbon (see JP-A-8-92168). And the like), according to the study of the present inventor, strongly adsorbs a part of the catalytic reaction product,
There are drawbacks such as impairing the durability of the reaction, and the regeneration of the catalyst is complicated, which is not preferable for industrial use. Further, the above-mentioned Japanese Patent Application Laid-Open Nos. 8-281108 and 8-2811
No. 14 proposes a method of using a metal oxide containing a metal oxide having a function as a redox agent as a support or a part of the support. The effect on the reaction yield and selectivity is insufficient, and the carrying capacity of noble metal compounds such as palladium may be insufficient, and the palladium metal and the redox agent dissolve in the reaction solution, resulting in an economical method. Not preferred.

[0006] As described above, no catalyst has yet been found which makes it possible to efficiently produce an aromatic carbonate by a simple process by reacting an aromatic hydroxy compound with carbon monoxide and molecular oxygen. It is.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a high activity which enables an aromatic carbonate to be produced economically and efficiently by reacting an aromatic hydroxy compound with carbon monoxide and molecular oxygen. And a catalyst system exhibiting selectivity, and a method for producing aromatic carbonate using the catalyst.

[0008]

The present inventors have conducted intensive studies to find a support component having such a function. As a result, a specific catalyst system was used to react an aromatic hydroxy compound with carbon monoxide and molecular oxygen. By doing so, it was found that an aromatic carbonate was obtained efficiently, and the present invention was completed. That is, the present invention includes the following inventions.

1. Reacting an aromatic hydroxy compound with carbon monoxide and molecular oxygen in the presence of (a) a complex of palladium and a heteropolyacid and (b) a quaternary ammonium salt or a quaternary phosphonium salt. Manufacturing method.

[0010] 2. Manganese as redox co-catalyst,
2. The production method according to 1, wherein at least one compound selected from the group consisting of salts of cobalt, copper, cerium and lead or compounds thereof coexists in the reaction system.

3. 3. The production method according to 1 or 2, wherein a quinone and / or a hydroquinone coexist in the reaction system.

4. The heteropoly acid has a Keggin structure, and the anion part thereof has the following formula (1) X (Mo) _n (W) _m (V) _p O ₄₀ (1) (where X is P Or Si element, and n, m, and p are 0
１２12, where n + m + p = 12. The method according to any one of 1 to 3, wherein

5. 5. The production method according to any one of 1 to 4, wherein the complex is obtained by introducing palladium into a cation portion of a heteropolyacid.

6. The complex and the quaternary ammonium salt or the quaternary phosphonium salt form the quaternary of the complex.
The method according to any one of claims 1 to 5, which is a quaternary ammonium salt or a quaternary phosphonium salt.

[0015] 7. 7. The production method according to any one of 1 to 6, wherein the reaction is performed under a gas flow for maintaining a constant partial pressure between carbon monoxide and molecular oxygen.

8. 8. The production method according to 7, wherein molecular sieve coexists as a dehydrating agent.

9. 9. The production method according to 7 or 8, wherein an inert solvent azeotropic with water or an ether organic solvent coexists in the reaction system.

10. The inert organic solvent or the ether organic solvent is benzene, toluene, xylene or diethyl ether, t-butyl methyl ether,
10. The production method according to 9, which is at least one compound selected from the group consisting of 1,2-dimethoxyethane and tetrahydrofuran.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION The aromatic hydroxy compound that can be used in the present reaction is an aromatic monohydroxy compound or a polyhydroxy compound, such as phenol, cresol, xylenol, trimethylphenol, tetramethylphenol, ethylphenol, Unsubstituted / substituted phenols such as propylphenol, methoxyphenol, ethoxyphenol, chlorophenol and bromophenol and their isomers; unsubstituted / substituted naphthols such as naphthol, methylnaphthol, chloronaphthol and bromonaphthol and isomers thereof Bisphenols such as bisphenol A, among which phenol is particularly preferred.

The gas component carbon monoxide and molecular oxygen used in the present invention can be used after being diluted with another gas that does not adversely affect the reaction, such as nitrogen, argon, carbon dioxide, etc. Air can also be used as oxygen in the form.

The reaction per se for reacting an aromatic hydroxy compound such as phenol with carbon monoxide and molecular oxygen to obtain an aromatic carbonate such as diphenyl carbonate is known.

In carrying out the above reaction in the method of the present invention,
It is characterized in that a palladium metal or a complex of a palladium compound and a heteropolyacid is used as a main catalyst.

Such a complex of palladium and heteropolyacid can be represented by a compound in which palladium is held in ionic or coordination bond with heteropolyacid.

The heteropolyacid used in the present invention has a structure in which an oxide such as Mo or W has a fixed structure in which oxygen atoms are shared around a central metal such as P or Si forming a central portion as described later. It is considered that a structure in which a heteropolyacid anion is formed by holding and surrounding the heteropolyacid anion, and a proton or a cation corresponding to the number of the heteropolyacid anion is present together with a water molecule forming a hydrate. In the present invention, palladium is generally used because it is relatively easy to prepare, has stability, and is used as a complex in a state where the proton or cation portion of the heteropolyacid is replaced. In some cases, Mo that forms the anion portion of the heteropolyacid
Alternatively, it can be used as a composite in which the W portion is replaced.

The amount of palladium complexed with the heteropolyacid used for the reaction as the above-mentioned main catalyst is 1 as a molar ratio of palladium atom to aromatic hydroxy compound.
It is preferably in the range of 10 ^-6 to 10 ^-6 , especially 10 ^-2 to 1
Range of 0 ^-5 are preferred.

The present invention is characterized in that a heteropolyacid is used as a complex with palladium as a main catalyst. Heteropoly acids are polyacids obtained by dehydration condensation of two or more types of oxyacids (oxo acids) and are composed of negatively charged oxide molecule clusters (polyanions) and protons (references, C
chemical Reviews, 1998, 98,
3-49). Further, it is preferable that the heteropolyacid has a structure called a Keggin type, and the structural formula of the anion portion is represented by the following formula (2) XM ₁₂ O ₄₀ ... (2).

In the formula, X is a P or Si element, or As or Ge.
And M is Mo or W, but V, M
It can be replaced with atoms such as n, Co, Cu, Fe, Zn and the like. And what has a proton with respect to this anion is called polyacid, but what replaced the proton with a cation is effective in this invention. In the present invention, such a cation portion can be used as a composite by replacing it with palladium, and the cation portion further includes alkali metals such as Li, Na, K, Rb, and Cs, and alkaline earths such as Ca and Mg. Metal, Cu, Zn, Al
Or a salt of a metal ion such as Fe, Co, Ni, Mn, Cr or the like, or a rare earth metal ion such as Ce or La, or the like, or an organic salt such as an ammonium salt or an organic ammonium salt. A salt that is also soluble in a solvent may be used. Since the solubility differs depending on the type of these salts, these heteropolyacids can be used as a catalyst for a homogeneous reaction or as a catalyst for a heterogeneous reaction.

Among these heteropoly acids having a Keggin structure, particularly preferred in the present invention are those having an anion moiety of the following formula (1) X (Mo) _n (W) _m (V) _p O ₄₀ as a Keggin structure heteropoly acid. (1) (where X is a P or Si element, and n, m, and p are 0
１２12, where n + m + p = 12. ). Hereinafter, the heteropolyacid of the present invention also includes salts thereof unless otherwise specified.

As a specific example, an anion part is
Illustratively, phosphotungstic acid; PW₁₂O₄₀, Rinmo
Lybdic acid; PMo₁₂O₄₀, Lintangstomolybdenum
Acid; PMo_TwoW_TenO₄₀, PMo_FourW₈O₄₀, PMo₆W₆O
₄₀, PMo₈W_FourO₄₀, PMo_{1 0}W_TwoO₄₀Etc., limbana
Domolybdic acids; PMo₁₁V₁O₄₀, PMo_TenV
_TwoO₄₀, PMo₉V_ThreeO₄₀, PMo_FourV₈O₄₀, PMo_TwoV_Ten
O₄₀Etc., Linvanado tungstic acid; PW₉V_ThreeO₄₀,
PW_TenV_TwoO₄₀, PW₁₁V₁O₄₀Etc., silicon tungsten
Acid; SiW₁₂O₄₀, Silicomolybdic acid; SiMo
₁₂O₄₀, Silicate molybdenum tungstic acid; SiMo_ThreeW₉O
₄₀, SiMo₆W₆O₄₀, SiMo₈W_FourO₄₀, SiMo_Ten
W_TwoO₄₀, Etc., Cavanado tungstic acid; SiW₁₁
V₁O₄₀, SiW_TenV_TwoO_{Four 0}, SiW₉V_ThreeO₄₀, SiW₈
V_FourO₄₀, SiW₆V₆O₄₀Tungsten, molybdenum
Acid; SiMo₁₁V₁O₄₀, SiMo_TenV_TwoO₄₀, SiMo
₉V_ThreeO₄₀, SiMo ₈V_FourO₄₀, SiMo₆V₆O₄₀, Si
Mo₈V_FourO₄₀Etc. or borotungstic acid; BW₁₂
O₄₀And the like. These heteropoly acids can be used alone
Or a mixture of two or more. Ma
As described above, salts of various cations or mixtures thereof
It can also be used in the form of a compound. These heteropoly
Complexes of acid and palladium include, for example:
And can be prepared by the following method. For example,
Only in the counter cation part of the above heteropolyanions
Or those introduced with protons or other cations.
I can do it. These palladium and heteropoly acids
Some are palladium salts and heteropolyacids or
Can be obtained by direct reaction with a salt of Among them
The simplest and most effective method is to use heteropolyacid and palladium.
Acetate; Pd (OAc)_TwoTo remove acetic acid
It is a way to leave. In this way, the heteropolyacid
Palladium metal in the thione part, usually in the form of divalent ions
Can be introduced, and the extra cation moiety remains as a proton.
To obtain a complex of palladium and heteropolyacid in the wet state
And the remaining protons can be
Complex of palladium and heteropolyacid in the form replaced by on
It can also be a body. Other heteropolyacid alka
Limetal salt or alkaline earth metal salt and palladium metal
Palladium using the so-called metathesis reaction with salts
Such a complex in which is introduced into the cation portion of the heteropolyacid
It is possible to get For example, heteropoly acids and carbonic acid
Preparation of barium salt of heteropoly acid by reacting barium
And then react with palladium sulfate to produce palladium
Obtain a complex with the heteropolyacid introduced into the cation moiety
be able to. In addition, heteropolyacids such as potassium bicarbonate
Neutralize with any base to bind the anion part of the heteropolyacid.
Activate and then react with palladium salt
A method of introducing palladium into lyric acid can also be used.
You.

These complexes of palladium and heteropolyacid can be used alone or in the form of a mixture of two or more. Further, this complex can be used in a form supported by a suitable carrier. Examples of such a carrier include those selected from alumina, silica gel, silica alumina, magnesia, titanium oxide, zirconium oxide, cerium oxide or a mixture thereof.

The amount of use of these heteropolyacids is usually in a state of forming a complex of about 1: 1 with palladium, so that it is in a range corresponding to the use amount of palladium described above.

The quaternary ammonium salt used in the present invention
And quaternary phosphonium salts of the formula R ₁R_TwoR_ThreeR_FourNX and
And R₁R_TwoR_ThreeR_FourPX (where R₁~ R_Four
Is an alkyl having 1 to 8 carbons or an alkyl having 6 to 12 carbons.
The reel group may be the same or different. X is ani
When turned on, hydroxyl, alkoxy, phenoxy, chloride
, Bromide, iodide and other halogens are often used
Can be Among them, especially tetra-n-butylammonium
Salts and tetraphenylphosphonium salts are preferred
No. Quaternary ammonium salt or quaternary ammonium salt used for the reaction
Of phosphonium salt is palladium or palladium
In a molar ratio of 0.1 to 1000 with respect to the compound,
Is preferably in the range of 1 to 100. The present invention
Quaternary ammonium salts and quaternary phosphonium
A quaternary ammonium salt of the above complex,
It is also preferred to use quaternary phosphonium salts.

In the present invention, in addition to (a) a complex of palladium and a heteropolyacid and (b) a quaternary ammonium salt or a quaternary phosphonium salt, quinones and / or Hydroquinones are used. Examples of the quinones include 1,4-benzoquinone, 1,2-benzoquinone, 3,5-di-tert-butyl 1,2-benzoquinone, 1,4-naphthoquinone, anthraquinone, and 2-ethyl-9,10-anthraquinone. ,
Examples thereof include 1,4-phenanthrenequinone and the like. Examples of hydroquinones include hydroquinone, catechol, 3,5-di-t-butylcatechol, resorcinol,
Examples thereof include 1,4-dihydronaphthalene, 9,10-dihydroanthracene, 2-ethyl-9,10-dihydroanthracene, and 1,4-dihydroxyphenanthrene. The preferred proportion of quinones and / or hydroquinones is 0.1 to 200 per mol of palladium.
Mol, more preferably in the range of 0.5 to 200 mol.

The aromatic carbonate production reaction of the present invention is more preferably carried out in the presence of a redox agent.

Such redox agents include I in the periodic table.
IIA, IVA, VA, VIA, IB, IIB, VI
B, VIIB, iron group (VIII) and rare earth metals (I
IIB). Compounds of these metals can be used in various oxidation states, for example, halides, oxides, hydroxides, carbonates, organic carboxylate salts, diketone salts, and complex salts such as oxalates and salcylates Besides, carbon monoxide, olefins, amines, phosphines and the like can be used as a coordinated complex. Among these metal compounds having a redox ability, preferred are manganese, cobalt, copper and compounds of rare earth metals such as lanthanum and cerium, and particularly preferred are compounds of manganese, cobalt, copper and cerium metal. . The amount of these redox agents to be used is not particularly limited, but may be 0.1 mol per mol of the palladium compound.
It is preferably in the range of from 1000 to 1000, particularly from 0.1 to
Preferably it is in the range of 100.

The production reaction of the aromatic polycarbonate in the present invention is carried out by the above-mentioned aromatic hydroxy compound and the above-mentioned catalyst,
Preferably, the components such as the above co-catalyst and the like are charged into a reactor, and the reaction is carried out under pressure and heat of carbon monoxide and molecular oxygen. At this time, in order to efficiently carry out the reaction, it is important to carry out the water produced by the reaction out of the reaction system as quickly and efficiently as possible. Conventionally, for example, a method in which a dehydrating agent such as molecular sieve coexists in the reaction system has been used.However, a method in which a generated gas is continuously carried out of the reaction system by an excess reaction gas using a gas flow type reactor. Is also effective. By using an organic solvent azeotropic with water, water can be more efficiently and continuously taken out of the reaction system.

Examples of the organic solvent azeotropic with water used in the present invention include organic solvents which have been recognized as azeotropic. So far, they directly participate in the reaction and react with the raw materials, Of course, those which react at a higher order with water are not suitable even if they are azeotropic with water. Therefore, aliphatic alcohols such as ethanol and those having active hydrogen such as primary and secondary amines may be involved in the reaction and are not suitable. In addition, since the azeotropic composition is generally affected not only by coexisting reactants but also by temperature and pressure,
It is desirable that the azeotropic temperature of the organic solvent with water under the reaction condition pressure is not significantly higher than the reaction temperature. The reaction temperature of the reaction of the present invention is 30 to 200 ° C, preferably 50 to 150 ° C.
° C, the azeotropic temperature under the reaction pressure is also
Preferably, it is close to that temperature range. As an example of an organic solvent satisfying such conditions, esters such as methyl acetate, ethyl acetate, ethyl acrylate, methyl methacrylate, methyl butyrate or ethyl benzoate, diethyl ether, methyl-t-butyl ether, 1,1 2
Ethers such as dimethoxyethane, tetrahydrofuran, anisole, and 1,4-dioxane; ketones such as cyclohexanone, 3-heptanone, 4-heptanone, and acetylacetone; chlorobenzene; chloroform;
Halides such as carbon chloride, nitrogen-containing compounds such as nitroethane, acrylonitrile, pyridine, 2-methylpyridine, 3-methylpyridine, and 4-methylpyridine; aliphatic hydrocarbons such as cyclohexane, hexane, octane, and didecane; Examples include aromatic hydrocarbons such as benzene, toluene, xylene, and naphthalene. In addition, two types of organic solvent mixed systems that form a ternary azeotrope with water may be used. There are many such combinations including unknown ones. For example, a combination of acetonitrile and benzene, methyl ethyl ketone and hexane, nitromethane and octane, t-butyl alcohol and benzene can be used. Among these, an organic solvent that does not mix with water is particularly preferable in consideration of separation from water separated from water and circulation reuse. Further, considering that the chemical reactivity is small and the influence on the reaction system is small and the separation from the catalyst component and the product is taken into consideration, especially methyl-t
Ethers such as -butyl ether, 1,2-dimethoxyethane and tetrahydrofuran, benzene, toluene,
Volatile aromatic hydrocarbons such as xylene are most preferred.

The amount used in the reaction of the above-mentioned organic solvent which forms an azeotrope with water is 1 to 0.01 parts by weight based on the amount of the aromatic hydroxy compound as a raw material during the reaction. Preferably it is in the range of 0.5 to 0.02. And, as a method of use, the above-mentioned organic solvent azeotropic with water may be mixed with the raw material aromatic hydroxy compound in a liquid state and supplied to the reaction phase, or may be supplied together with the gaseous raw material in a partially vaporized state. It may be supplied to the reaction phase. After the organic solvent azeotropic with water stays in the reaction phase, a part or most of the organic solvent is discharged from the reaction phase as a gas together with the water azeotropically used with a gaseous reactant usually used in excess.
Thus, by separating and removing water from the discharged gaseous mixture and returning to the reaction phase again, water generated by the reaction is continuously removed from the reaction phase without substantially losing the organic solvent and the reaction gas. It is possible.

In this case, it is safe and preferable to keep the partial pressure ratio between carbon monoxide and molecular oxygen constant and keep the total pressure constant. The reaction pressure is 1 to 300 atm, preferably 1 to 150 atm, more preferably 2 to 300 atm.
The range is 100 atm. In addition, the partial pressure ratio between carbon monoxide and molecular oxygen is preferably kept constant, but the composition ratio is preferably out of the explosion range from the viewpoint of safety. The partial pressure ratio between carbon monoxide and molecular oxygen varies depending on the total pressure and the ratio of the contained inert gas component, but is usually selected from the range of 5: 1 to 30: 1. Thus, the composition ratio of the gas supplied during the reaction can be kept constant to maintain the optimum gas composition for the reaction, and at the same time, the reaction can be performed while continuously removing water generated by the reaction.

The reaction temperature is 30-200 ° C., preferably 5
The range is 0 to 150 ° C. The reaction time varies depending on the reaction conditions, but is usually several minutes to several hours.

In the reaction, various inert solvents can be used as the solvent, but those having a relatively high vapor pressure may be used together with the reaction gas when the reaction is carried out under the above-mentioned gas flow conditions. Gradually lost. Therefore, the aromatic hydroxy compound of the reactant is usually used as the reaction solvent, and no other solvent is used in many cases.

FIG. 1 schematically shows a small gas flow type reaction apparatus as an example.

The reaction apparatus shown in FIG. 1 uses carbon monoxide and molecular oxygen (or air) whose molar ratio and partial pressure are kept constant.
At a constant flow rate of about 10 to 800 ml / min
Can be continuously supplied in the range of The capacity of the reactor 10 is 10
0 ml, cylindrical, 30 mm in diameter, equipped with a gas blowing tube and rotary stirring blades. Assuming that the reaction gas 1 is carbon monoxide and the reaction gas 2 is molecular oxygen (or air), the pressure regulators 12 adjust the predetermined reaction pressure via the valves 3 and 4 and the pressure regulators 5 and 6 respectively. The pressure is adjusted to 1 to 5 atm higher than the pressure. As a result, a predetermined flow rate of gas is supplied through the constant flow rate gas supply devices (mass flow controllers) 7 and 8, and is supplied to the reactor 10 through the gas mixing preheater 9.
The gas component passing through the reactor passes through a cold trap 11,
Further, the air is exhausted through the pressure regulator 12. The pressure in the reactor is regulated by a pressure regulator 12.

In the example of the reactor shown in FIG. 1, the gas exiting the reactor is led to a cold trap 11, where water and a part of the solvent generated are collected, and the unreacted gas is adjusted in pressure. It is collected outside the system via the vessel 12, but can be recycled after adjusting the gas composition as required.

After completion of the reaction, the reaction mixture is taken out of the reactor. The catalyst of the present invention can be separated and recovered by a method such as filtration, centrifugation or magnetic separation, and can be reused. In the case of a fixed bed type, this separation operation is not necessary. The desired aromatic carbonates can be separated, purified, and isolated by a method such as filtration, distillation, crystallization and the like.

[0046]

EXAMPLES The present invention will be specifically described below with reference to examples.

[Example 1]

[Preparation of palladium heteropolyacid complex]
1.15 g (0.5 mmol) of silicomolybdic acid; H ₄ SiMo ₁₂ O ₄₀ .nH ₂ O (n ≒ 28 manufactured by Nippon Inorganic Chemical Industry Co., Ltd.) is dissolved in 5 ml of water, and palladium acetate; Pd (OA
c) Add 2 112 mg, warm and evaporate the water.
At this time, heating is avoided by adding a small amount of water until the added palladium acetate is completely dissolved and the odor of acetic acid disappears in the vapor to be evaporated. Finally, the water was evaporated to dryness to obtain a palladium-heteropolyacid complex having a composition of PdH ₂ SiMo ₁₂ O ₄₀ .nH ₂ O.

This complex was dissolved in a total amount of 30 ml of water,
0.75 g of tetrabutylammonium bromide (2.3
3 mmol), and the mixture is stirred for about 1 hour, and the precipitate is filtered and dried. Thus, the tetrabutylammonium salt of the above complex; (Bu ₄ N) ₂ PdSiMo ₁₂ O
About 1.57 g of a solid powder was obtained as a palladium heteropolyacid composition having a composition of ₄₀ · nH ₂ O.

[Reaction using the above-mentioned palladium-heteropolyacid complex] Using a reactor shown in FIG. 1, 47.0 g (0.5 mol) of phenol and palladium-SiM
o ₁₂ O ₄₀ -tetrabutylammonium complex; (Bu
_{4 N) 2 PdSiMo 12 O 40} · nH 2 O 500mg (0.
16 mmol), manganese acetate; Mn (OAc) ₂ 5
5 mg (0.32 mmol), tetra n-butylammonium bromide; 968 mg of Bu ₄ NBr (3 mmo
l) and 7.0 g of molecular sieve (4 °; powder) were charged and the reactor was replaced with carbon monoxide. At the same time as the temperature of the reactor was raised to 80 ° C., the pressure was raised to 8 bar with carbon monoxide. When the temperature reached a predetermined temperature and pressure, the reaction was carried out at a carbon monoxide flow rate of 500 mL / min and an oxygen flow rate of 35 mL / min for 3 hours. Was. After the reaction was completed, the reactants in the reactor were taken out and analyzed by gas chromatography.
3 g (19.2% yield) of diphenyl carbonate (D
PC). The reaction selectivity was about 98.9%.

[0051] [Example 2] palladium acetate and silicotungstic acid in the same manner as in Example _{1; H 4 SiW 12 O 4} 0 · 2
(TBA) 2PdSiW ₁₂ O from 9H ₂ O (manufactured by Nippon Inorganic Chemical Co., Ltd.) and tetrabutylammonium bromide
_A composite having a composition of ₄₀ · nH ₂ O was prepared, and the composite 6
26 mg (0.16 mmol) of phenol 4
7.0 g (0.5 mol) and manganese acetate; Mn (OA
c) ₂ 55mg (0.32mmol), tetra-n- butylammonium bromide; Bu ₄ NBr; 968m
g (3 mmol) and 7.0 g of molecular sieve (4 °; powder) were charged, and the flow rate of carbon monoxide was 500 mL / m.
in, oxygen flow rate 30 mL / min, reaction pressure 8 bar,
The reaction was performed at a reaction temperature of 80 ° C. for 3 hours. After the completion of the reaction, the reaction product in the reactor was taken out and analyzed by gas chromatography to obtain 9.3 g (yield 17.4%) of diphenyl carbonate (DPC). Reaction selectivity is about 9
It was 8.7%.

Example 3 The palladium-heteropolyacid complex (Bu ₄ N) ₂ PdSiMo ₁₂ O prepared in Example 1
Phenol 20.0 g (0.425 mol) and manganese acetate; Mn (OAc) ₂ 27.5 mg (0.16 mm) using ₄₀ · nH ₂ O; 250 mg (0.08 mmol)
ol), tetra n-butylammonium bromide; B
500 mg (1.5 mmol) of u ₄ NBr, 7.0 g of molecular sieve ( ₄ °; powder), 30 g of methyl-t-butyl ether as a solvent were charged, and the flow rate of carbon monoxide was 500 mL / min (standard state) and the flow rate of pure oxygen was adjusted. 35 mL / min (standard condition) is passed and the reaction pressure is 8
The reaction was carried out for 3 hours while maintaining the reaction temperature at 80 ° C. After the completion of the reaction, the reaction product in the reactor was taken out and analyzed by gas chromatography to find 6.4 g (yield 28.2%).
Of diphenyl carbonate (DPC) was obtained. The reaction selectivity was about 98.9%.

Examples 4 to 8: 50.0 g of phenol
(0.53 mol), using the catalysts shown in Table 1, in the same manner as in Example 1, molecular sieve (4 °; powder)
Charge 7.0 g and adjust the flow rate of carbon monoxide to 500 mL / mi.
n (standard condition) and the flow rate of pure oxygen at 35 mL / min
(Standard conditions) and a reaction pressure of 8 bar and a reaction temperature of 8
The reaction was maintained at 0 ° C. for 3 hours. After completion of the reaction, the reactants in the reactor were taken out and analyzed by gas chromatography. Table 1 shows the results. (The Pd-HPA complex shown in the table further contains an unspecified number of H2O and TBAB unspecified substances.)

[0054]

[Table 1]

[Comparative Example 1] In the same manner as in Examples 1 and 2, 50.0 g (0.53 mol) of phenol, palladium acetate; 0.16 mmol of Pd (OAc) ₂ , 0.69 mmol of benzoquinone, manganese acetate; Mn (OAc) ₂
0.32 mmol and tetra n-butylammonium bromide; 3 mmol of Bu ₄ NBr and 7.0 g of molecular sieve (4 °; powder) were charged, the flow rate of carbon monoxide was 500 mL / min (standard state), and the flow rate of pure oxygen was 30 mL / The reaction was carried out for 3 hours at a reaction pressure of 8 bar and a reaction temperature of 80 ° C. As a result, the DPC yield was 1.09 g (1.9% yield),
The DPC selectivity was 78%.

[0056]

Industrial Applicability According to the present invention, a high activity and a high selectivity enabling an economical production of an aromatic carbonate from an aromatic hydroxy compound, carbon monoxide and molecular oxygen with high yield, high selectivity and It is possible to provide the catalyst shown and a reaction method using the catalyst.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a small gas flow type reaction apparatus.

[Explanation of symbols]

 1. Reaction gas 2. Reaction gas 3. Valve 4. Valve 5. Pressure regulator 6. Pressure regulator 7. 7. Constant flow gas supply device (mass flow controller) 8. Constant flow gas supply device (mass flow controller) Gas mixing preheater 10. Reactor 11. Cold trap 12. Pressure regulator

Continued on the front page (72) Inventor Masaharu Muramoto 2-1 Hinodecho, Iwakuni-shi, Yamaguchi Prefecture Teijin Limited Iwakuni Research Center (72) Inventor Yuzo Fujiwara 6-10-1, Hakozaki, Higashi-ku, Fukuoka City Graduate School of Engineering, Kyushu University Graduate School of Materials Science and Engineering (72) Inventor, Teizo Yamaji 6-10-1 Hakozaki, Higashi-ku, Fukuoka City Kyushu University Graduate School of Engineering, Materials Science and Engineering (72) Inventor Jia Narikuni 6-10 Hakozaki, Higashi-ku, Fukuoka City No. 1 Kyushu University Graduate School of Engineering, Department of Materials Creation Engineering (72) Inventor Yun Kunikawa 6-10-1 Hakozaki, Higashi-ku, Fukuoka City Kyushu University Graduate School of Engineering, Department of Materials Creation Engineering F-term 4G069 AA06 AA08 BA21A BA21B BB07A BB07B BC21A BC31A BC43A BC54A BC59A BC59B BC60A BC60B BC62A BC62B BC67A BC72A BC72B BD01A BD01B BD03B BD05A BD05B BD06A BD06B BA07A BD07B BD13BA BE08A BE08B BA17A BE17A BA18 BA18A BA18 BA18A 3 BA35 BA50 BA51 BA53 BA75 BA91 BB10 BB15 BB25 BC11 BD20 BE30 4H039 CA66 CD10

Claims (10)

[Claims] 1. An aromatic hydroxy compound, carbon monoxide and molecular oxygen, comprising: (a) a complex of palladium and a heteropolyacid; and (b) a quaternary ammonium salt or a quaternary ammonium salt.
A method for producing an aromatic carbonate in the presence of a secondary phosphonium salt. 2. The process according to claim 1, wherein at least one compound selected from the group consisting of manganese, cobalt, copper, cerium, lead salts and compounds thereof is co-existed in the reaction system as a redox cocatalyst. 3. The process according to claim 1, wherein a quinone and / or a hydroquinone coexist in the reaction system. 4. The heteropoly acid has a Keggin structure,
And the anion part thereof is represented by the following formula (1): X (Mo) _n (W) _m (V) _p O ₄₀ (1) (where X is a P or Si element, and n, m, p Is 0
１２12, where n + m + p = 12. The method according to any one of claims 1 to 3, which is represented by the following formula: 5. The method according to claim 1, wherein the complex is obtained by introducing palladium into a cation portion of a heteropolyacid. 6. The method according to claim 1, wherein said complex and said quaternary ammonium salt or quaternary phosphonium salt are quaternary ammonium salts or quaternary phosphonium salts of said complex. 7. The process according to claim 1, wherein the reaction is carried out under a gas flow for maintaining a constant partial pressure between carbon monoxide and molecular oxygen. 8. The method according to claim 7, wherein a molecular sieve coexists as a dehydrating agent. 9. The reaction system in which an inert solvent azeotropic with water or an ether organic solvent coexists.
Production method as described. 10. The method according to claim 10, wherein the inert organic solvent or the ether organic solvent is benzene, toluene, xylene or diethyl ether, t-butyl methyl ether, 1,2-
The method according to claim 9, which is at least one compound selected from the group consisting of dimethoxyethane and tetrahydrofuran.