JPS5931730A - Preparation of lower aliphatic carboxylic acid and derivative thereof - Google Patents

Abstract

PURPOSE:To obtain selectively a lower aliphatic carboxylic acid and a derivative thereof, by using a hafnium compound as a catalyst in reacting carbon monoxide with hydrogen in the liquid phase in the presence of the catalyst and an organic solvent under heating and pressurizing. CONSTITUTION:Carbon monoxide is reacted with hydrogen in the liquid phase in the presence of a hafnium compound, preferably a hafnium compound soluble in the reaction system, particularly a hafnium halide, as a catalyst and an organic solvent, preferably an aprotic dipolar solvent, e.g. an ester, polyether, sulfone or amide, etc. preferably under pressurizing and heating under 1,000- 50kg/cm<2>.G at 150-300 deg.C to give the aimed lower aliphatic carboxylic acid and a derivative thereof containing acetic acid as a main component and a small amount of propionic acid, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing lower aliphatic carboxylic acids and derivatives thereof by reacting -carbon oxide and hydrogen in the presence of a catalyst.

Conventionally, many catalyst systems have been proposed for methods of producing acetic acid, methyl acetate, lower aliphatic carboxylic acids, and derivatives thereof by reacting -carbon oxide with hydrogen. These include, for example, Japanese Unexamined Patent Publication No. 51-80806,
Japanese Patent Publication No. 54-41568, Japanese Patent Publication No. 51-8 (11
B07 publication, JP-A-52-14706, U.S. Patent No. 4,096,164, JP-A-54-13850
．． No. 1, JP-A-54-1-41705, U.S. Pat. No. 4,101,450, JP-A-55-143'
As proposed in Publication No. 918, etc., all of them are catalysts whose main component is rhodium, and by combining rhodium with promoter components such as iron, manganese, molybdenum, tungsten, magnesium, chromium, and ruthenium. , which aims to improve the catalytic activity, selectivity and catalyst life of rhodium catalysts. By combining these co-catalyst components to form a multi-component catalyst, the respective catalyst activity, selectivity or catalyst life can be considerably improved, but there is a drawback that the price of the rhodium catalyst is extremely high.

In addition, - when reacting carbon oxide with hydrogen, if a multi-component catalyst consisting of a combination of rhodium and a co-catalyst component selected from zirconium, hafnium, lanthanum, platinum, chromium and mercury is used, lower JP-A-55-52727 proposes that it is possible to significantly suppress the selectivity to aliphatic carboxylic acids and their derivatives and to produce ethanol with high selectivity. From this description, it is impossible to know that lower aliphatic carboxylic acids and their derivatives can be selectively obtained by using these promoter components alone.

In view of the shortcomings of conventional catalyst threads, the present inventors searched for a new catalyst that can produce lower aliphatic carboxylic acids and their derivatives through a catalytic reaction between -carbon oxide and hydrogen, and as a result, hafnium compounds were discovered. It was discovered that it can act as a catalyst for this reaction, and the present invention was achieved.

That is, the present invention provides, in the presence of a catalyst and an organic solvent,
A method for producing lower aliphatic carboxylic acids and derivatives thereof by reacting carbon monoxide and hydrogen under conditions of heating, pressurization, and liquid phase, characterized in that the reaction is carried out in the presence of a hafnium compound catalyst. It's a method.

The catalyst used in the method of the invention is a catalyst consisting of a hafnium compound. Here, the hafnium compound catalyst is a catalyst made of a compound containing hafnium atoms as a main component as transition metal atoms. This catalyst may contain other metal compounds, organic ligand compounds,
It is also possible to add various anionic compounds as co-catalyst components. Specifically, the hafnium compound is
Hafnium oxides such as hafnium dioxide and hafnium trioxide, sodium hafnate (Na 2 Hr O
3), potassium hafnium capped (K2Hf'03), sodium beroxohafnate (N a 4Hf O4
・4H202・2H20), potassium belloxohafnate (K4■fO4・4H202・2H20)
hafnates, hafnium dichloride, hafnium tribromide, hafnium diiodide, hafnium trichloride, hafnium tribromide, hafnium triiodide, hafnium tetrafluoride, etc.
Halides such as hafnium tetrachloride, hafnium tetrabromide, hafnium tetraiodide, oxyacids such as hafnium nitrate, hafnium sulfate, hafnium phosphate, hafnium silicate, hafnium tetraacetate, basic hafnium acetate, hafnium oxalate, fi Organic acid salts such as hafnium petroate and hafnium benzoate, hexafluorohafnate (N
Examples include complex salts such as a 2 CHr F 6 )), octafluorohafnate (K4[HfF6], and octaoxalatohafnate (K (Hf(C204)4)). Hafnium metal can also be used because it forms a carbonyl complex in the reaction system and dissolves therein. Among these hafnium compounds, hafnium compounds that are soluble in the reaction system are preferred, and halo and hydrogenated hafnium are particularly preferred.

The proportion of the hafnide metal catalyst used in the method of the present invention is usually 10-6 to 1 gram atom/11 and preferably 10-4 to 5xio' Durham atom/l as the concentration of /X7 nium atoms in the reaction system. , particularly preferably in the range from 10 to 10 g atoms/l.

In the process of the invention, the reaction of -carbon oxide and hydrogen is carried out in the presence of a solvent. As the solvent, any organic solvent can be used as long as it is inert to the reaction, and specifically, tetrahydrofuran, dimethyl ether of diethylene glycol, dimethyl ether of tetraethylene glycol (tetraglyme), diethyl ether, diisopropyl ether, dioxane, 1. Ethers such as 2-dimethoxybenzene and 18-crown-6; methyl acetate, ethyl acetate, butyl acetate, ethylene glycol diacetate, diethylene glycol diacetate, γ
-butyrolactone, dimethyl-r-butyrolactone, δ
-Esters such as valerolactone; Sulfones such as sulfolane and dimethylsulfone; Sulfoxides such as dimethylsulfoxide and diethylsulfoxide: N,
N-dimethylformamide, N,N-diethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, N-ethylpyrrolidone, N-isopropylpyrrolidone, N-propylpyrrolidone1. N-butylpyrrolidone, 1,3-dimethyl-2-imidazolidinone, N-
Amides such as methyl-2-pyridone; phosphoric acid triamides such as hexamethyl phosphoric triamide and hexamethyl phosphoric triamide; N, N, N', N
Substituted ureas such as '-tetramethylurea and 1,6-dimethyl-2-imidazolidinone; Alcohols such as methanol, ethanol, 2-methoxyethanol, ethylene glycol, diethylene glycol, and triethylene glycol; Hexano, heptane, hexene, Examples include hydrocarbons such as cyclohexane, naphtha, and kerosene; aromatic hydrocarbons such as benzene, l-toluene, and xylene. Among these solvents, it is preferable to use aprotic dipolar solvents such as esters, polyethers, sulfones, and amides because they improve the reaction rate.

In the method of the present invention, the ratio of carbon monoxide and hydrogen gas supplied to the reaction system is usually in the range of 20 to 0.05, preferably 5 to 0.2 as a molar ratio of carbon monoxide to hydrogen gas. be.

In the method of the invention, the reaction is carried out under heated and pressurized conditions. The pressure during the reaction is usually 2000 to 1 kg/
cm −o , preferably 100D to 50kg/c
The range is m-G. In addition, the temperature during the reaction is usually 50°C.
from 150 to 300°C, preferably from 150 to 300°C
is within the range of The time required for the reaction is usually 0.1 to 2
0 hours, preferably in the range of 0.5 to 10 hours. The reaction is usually carried out under stirring conditions.

In the method of the present invention, lower aliphatic carboxylic acids and derivatives thereof can be isolated by treating the reaction mixture after completion of the reaction by conventional methods such as distillation and extraction. The lower aliphatic carboxylic acids and their derivatives obtained by the method of the present invention include acetic acid as a main component and a small amount of propionic acid. In addition to the above-mentioned lower aliphatic carboxylic acids and derivatives thereof, the main products obtained in the method of the present invention include methane and carbon dioxide gas.

Next, the method of the present invention will be specifically explained using examples.

Example 1 After replacing the inside of a Hastelloy C autoclave with an internal volume of 50 m1 with argon, this autoclave was filled with Hr.
The autoclave was closed with 40.4 milligram atoms of r and 10 ml of N-methyl-2-pyrrolidone (NMp). Next, a mixed gas with a carbon monoxide/hydrogen molar ratio of 1/1 was introduced into the autoclave from the gas introduction pipe into the reaction system at a pressure of 500 to 550 kg/Cm and a temperature of 24.
The reaction was carried out at 0°C for 4 hours.

After the reaction was completed, the mixture was cooled to room temperature, and the residual gas and reaction mixture were taken out and quantified by gas chromatography. The results are shown in Table 1.

Examples 2 to 7 The same procedures as in Example 1 were carried out except that the conditions shown in Table 1 were used. The results are shown in Table 1.

Claims (1)

[Claims] (1) Presence of a catalyst consisting of a hafnium compound in a method for producing a lower aliphatic carboxylic acid by reacting carbon monoxide and hydrogen under heating, pressure and liquid phase conditions in the presence of a catalyst and an organic solvent. A method characterized in that the reaction is carried out below.