SK37994A3 - Method of preparing of carboxylic acids or their esters - Google Patents

Abstract

The present invention relates to the preparation of carboxylic acids or of the corresponding esters by reaction of an alcohol with carbon monoxide in the presence of a catalyst containing iridium and of a halogenated promoter. The reaction is carried out with a reaction mixture whose composition is maintained throughout the operation. The said mixture comprises between 0 exclusive and 10% of water, between 0 exclusive and 10% of halogenated promoter, and between 2 and 40% of ester corresponding to the reaction of the abovementioned carboxylic acid and alcohol, the said carboxylic acid constituting the solvent of the reaction.

Description

Technical field

The present invention relates to a process for the production of carboxylic acids or to the like

Their esters are liquid-phase carbonylated alcohol in an iridium-based catalyst.

The prior art

Production of carboxylic acids. in particular acetic acid, by reacting carbon monoxide with an alcohol such as ethanol in the presence of a homogeneous catalyst is a known process that has been predated by a series of patents and articles. The catalysts which can be used in this type of reaction, the district of Others, are cobalt, rhodlua and Iridium.

Only carbonylation processes utilizing radio-based catalysts are commonly used in nano-aerospace and are predetermined for further development. Recent generations of these processes utilize radio, considerable and abundant soluble iodine salts, which stabilize the above-mentioned metal with low water contents. They are high-performance because they allow to achieve a carbonylate-ethanol-acetic acid-per-acetic acid rate of 10 Bol / l.h.

Cobalt-catalysed carboxylic acid production is no longer predetermined for new research work due to the large pressure and temperature reaction conditions. The results with respect to the selectivity of the acid formed are fairly satisfactory compared to the obstacle to be overcome.

As far as processes using 1dldla based catalysts are concerned, the results obtained show a very low performance. Carbonylate rates of from 2 to 4 aol / hr of the produced acid are reported, as long as the number of salts used in the reaction is considerable. This corresponds to the activity of the catalyst for the formation of acetic acid sols produced on Iridium aol per hour, which is no more than 1000.

PQflltá.ta. YYP * lBSM

It is therefore an object of the present invention to provide a process for the production of carboxylic acids by carbonylation reaction of a suitable reactant, in which the catalyst is not used by a rhodium-based catalyst, but at the same time the performance of the processes using the above catalyst.

Accordingly, the process of the present invention is the production of carboxylic acids or their esters containing n + 1 carbon atoms by reacting carbon monoxide in liquid at least one alcohol and containing n carbon atoms in the presence of a catalyst system based on Iridium and a prosdtor containing halo. The process according to the invention aa characterized in that during the reaction water is maintained in the atmosphere at 0 to 10 h, in the presence of 0 to 10 h in an ester corresponding to the exemplified carboxylic acid and the alcohol in the range of 2 to 40. forms a solvent for the reaction.

Throughout the text, unless otherwise indicated, the percentages indicated are percentages by weight based on the total weight of the reaction zaeal.

Surprisingly, the process according to the invention, carried out in an iridium-rich catalyst under the above-mentioned stable conditions, is much more powerful than the methods described in which aa uses this catalyst. In addition, and importantly, the process of the present invention provides for the carbonylation rates of the alcohol to the carboxylic acid expressed in salts to be comparable to the rates. It has been established that the catalyst has been catalyzed by the use of similar catalyst catalysts.

Okree of this was observed in contrast to what was expected, the Xe catalyst remained stable in the reaction environment with

low water content 1 in the absence of any kind of compound that stabilizes the catalyst, organic or inorganic cell. Consequently, the process of the invention has the advantage that Xe does not need to be used during the reaction.

It should be noted that Xe and the process according to the invention are carried out in the presence of relatively large halogen-containing promoter compositions. This has the advantage of reducing the promoter which can be separated from the acid formed and of destroying the energy consumption required to regenerate the halogen-containing compound as well as the actual consumption of the compound, i. its consumption during the continuous carrying out of the carbonylation process. In addition, this opetrenle allows to destroy, for a given water and ester content, the acid content corresponding to the halogen of the pro-reactor in the reaction medium. As a result, the corrosivity of this environment is destroyed, which makes the simpler and more costly choice of setterals to be in contact with the environment.

Finally, it has been found that the teachings of these conditions have been largely selective in terms of the fact that the side-by-side products, such as proponic acid and formic acid, are largely low.

The amount of each of the above acids formed during the reaction is usually less than 30 ng / k. of an acid or ester produced.

Further advantages of the process according to the invention will become apparent from the following description.

As noted above, the carbonylation reaction of the present invention is carried out in the presence of a catalytic aystea based on at least one Iridium compound and one halogen-containing promoter.

Since the reaction is carried out in the liquid phase, the catalyst is in the form of compounds which are soluble in the reaction mixture.

It is possible to use all compounds which are soluble or which can be dissolved in the reaction medium in the production conditions according to the invention. Non-limiting examples include, but are not limited to, iridium in the metal state, simple aol of the metal, oxides or coordination coaplexes as particularly suitable for carrying out the process of the invention.

Iridium halides are usually used as simple aoll iridium. The halogen is at most selected from chlorine, gate or iodine. Iodine is preferably used. Thus, compounds such as Irl, Irbr, IrCl can be used in the process of the invention.

- Irl 4 H 10 and ZrBr 4 H 10 O.

Likewise, the oxides selected from 1 Ir10 and H2O2 are suitable for use in the method of the invention.

In the case of soluble capsules, most commonly, and use those compounds that find Uganda selected from carbon monoxide or a combined carbon monoxide / halogen, the halogen is selected from chlorine, bromine or especially iodine. However, the use of soluble Iridium compounds in which the Ugandans are selected from organophosphorus or organo-nitrogen compounds is excluded.

As is known to those skilled in the art, coordination coaplexes which are particularly suitable for carrying out the invention and can not be applied without this.

in order to limit the scope of the invention, the following = 1 smoked: Ir. (CO), Ir (CO) _and I _and -C *. Ir (CO) aBra-G * and Ir (CO) aCl..C *, however, in these formulas Q can represent at least hydrogen, the group HR- or PR-, where R represents hydrogen or a hydrocarbon radical.

These catalysts can be obtained in any manner known to those skilled in the art.

According to a particularly preferred process, however, a catalyst solution can be prepared from a carbonyl compound of Iridium, for example with Ir- (CO) - a, contacting the compound with hydroiodic acid and / or a precursor of this acid in the solvent. As a precursor capable of releasing hydroiodic acid, mention may be made, for example, of iodine, alkyl iodides and 1 to 10 carbon atoms or alkanoyl iodides and 1 to 10 carbon atoms. With respect to solvents, any compound may be used as long as it dissolves hydroiodic acid or a precursor thereof and the compounded iridium-based compound. They use and hire a solvent or solvent selected from water, carboxylic acids or their esters obtained by the process of the invention. The reactants aa are scaled at a total pressure of 0.1 to 1 HPa and at a temperature at least equal to the boiling point of the above solvent under conditions in which the aa reactants are mixed. This can be done under the air ataoamer. Inert gas or carbon monoxide.

Another preferred method of preparing a catalyst solution suitable for practicing the invention is a process wherein aa are mixed in the liquid phase with one or more iridium oxides that are hydrated with hydroiodic acid or a compound capable of liberating hydroiodic acid. Hydrochloric acid may be used in the form of a gas or solution, in particular an aqueous solution. It can also be used in the forae of a precursor, in particular the one mentioned in the previous variant. The amount of acid used is such that the number of hydroiodic acid (s) and the number of iridium (s) can be varied from 1 to 100. The process of the invention can be carried out under the ataosphere of air, inert gas or lithium oxide. aaaotic or in cabbage.

The total concentration of Iridium in the reaction mixture of the vessel is usually 0.1 and 100 bboI / L, and preferably 1 and 29 bboI / L.

The second component of the catalytic system is a halogen-containing pro-ion. This may be in the form of an halogen atom or in combination and may be a compound of, for example, hydrogen, an alkyl group of 1 to 10 carbon atoms, an acyl group of 1 to 10 carbon atoms, or an aryl group of 6 to 10 carbon atoms.

The halogen is usually selected from chlorine, bromine or iodine. Preferably, aa uses iodine.

Suitable halogen-containing compounds suitable for carrying out the invention include, but are not limited to, iodine, hydroiodic acid, hydrobromic acid, ethyl iodide, ethyl bromide, ethyl iodide. ethylhronol, 1,1-diiodoethane, benzylhroeld and acetyl iodide.

According to a particular embodiment of the invention, the only pro-ator comprises hydrogen or an alkyl moiety having 1 to 10 carbon atoms. It comprises a halo proactive agent used in the practice of the invention, a halogen and an alkyl habit, and 1 to 10 carbon atoms.

This embodiment aa, and preferably, is carried out in a propanol salt containing a halogen having a hydrocarbon residue corresponding to the alcohol used as reactant in the reaction according to the invention.

The content of the halogen-containing promoter in the reaction medium ranges from 0 (exclusively) to 10%. According to a particular embodiment of the invention, the content of the halogen-containing compound in the reaction medium ranges from 1 to 6 t.

Hereinafter, the reactants will be used in the process of the invention.

As mentioned above, the reaction according to the invention is carried out in the presence of an alcohol containing one carbon atom and which is the preferred carboxylic acid or ester produced.

Hedzl reactants which are suitable for carrying out the reaction and which are saturated with alcohols and 1 to 10 carbon atoms. These alcohols may be aonohydroxylated or dihydroxylated. Examples of such compounds include, but are not limited to, ethanol, ethanol, propanol, butanol, and 1,4-hutanedol.

According to a preferred embodiment, the alcohols used are selected from the monohydroxylated compounds.

It should be noted that the alcohol used as the reactant may be added as such or in a spiked form in the reaction of the environment. This alcohol may either be in the form of a halogen-containing derivative and / or an ether or a / aater obtained by the reaction and in particular the alcohol and the carboxylic acid present.

The reactant content of the reaction medium and thus can be varied in a wide range due to the differences in the compounds. which may be a reactant.

As a result, the alcohol content per se in the reaction medium should preferably be from 0 to 10 L. Preferably, the alcohol content in the reaction medium is 0.1 to 8%.

The second reactant required to obtain the carboxylic acid is carbon monoxide. Tan aa Will be used in the Sieve or diluted in gases such as hydrogen, aethane or carbon dioxide, or in any type of gas such as nitrogen.

According to a particular embodiment of the invention, aa uses carbon monoxide which has a 99% yield.

The partial pressure of carbon monoxide is usually 1 and 9 MPa, the train comes into consideration 1 partial pressures a and o of this range.

The carbonylation reactions according to the invention are, moreover, carried out in water, the water content of the reaction medium being 0 to 10%. 10 í. According to a particular embodiment of the invention, the water content of the reaction medium is 2 to 8%.

In addition to the above reactant compounds, and in carrying out the process according to the invention, they use ejectors corresponding to and preferably the reaction of the alcohol used in the reaction and the acid.

The carboxylic acid present in the reaction medium. The eater content in this environment is 2 and 40 i. According to a particular embodiment of the invention, the estar content is S to 30%.

The haplo aa process of the invention is carried out in a solvent which preferably corresponds to the carboxylic acid or ester formed by the reaction.

As mentioned above, the invention consists in maintaining water, a halogen-containing promoter in the reaction medium, ironing said ester and carboxylic acid in the processes just specified. As a result, the invention is intended to be implemented in a continuous manner in particular, and a stable working process corresponds to said composition and said polymer.

and starting the reaction a and the individual components are fed to a suitable reactor, provided with a flue gas apparatus sufficient for the gas-liquid transport. It should be noted that, if the reactor and preferably is equipped with a plant for mixing the reaction mixture, work without such a plant is not excluded, and the homogenization achieves the introduction of carbon monoxide into the reactor.

The components of the reaction medium aa are fed to the reactor in any order in their own form and / or in the form of one or more precursors.

A first variant of the invention consists in introducing the above-described halogen-containing promoter for the reaction reaction.

The second option consists in bringing this proa into a fora of one vague precursor.

In this case, the precursor is usually a compound which is capable of releasing the above-mentioned residue with the above-mentioned halogen-containing pro-proctor by reacting the precursor with halogen or the corresponding acid which is added or reacted in the reaction medium. účeloa.

As examples of suitable precursors that do not limit the scope of the invention, compounds selected from alcohols of formula (I) ROH, ethers of formula (2, ROR 'or eateres of formula (3) R'COOR, whether or not anaerobic or zeal. in the above formulas, the substituents R and R *, which may be the same or different, each alkyl radical of from 1 to 10 carbon atoms, the acyl radical and from 1 to 10 carbon atoms or the aryl radical and from 6 to 10 carbon atoms, the radical R being a halogen-containing pro-promoter residue.

Preferred is a precursor of said halogen-containing pro-ator such as ethanol, ethanol, propanol, butanol, diethyl ether, dlatyl ether, atylene oxide, and acetyl acetate.

The carbonylation reaction aa is usually carried out at a temperature of 190 to 290 ° C. The reaction temperature aa preferably ranges from 180 to 210 ° C.

The total pressure is usually in the range of from 0.3 to 20 HFa and has been employed from 0.9 to 10 HPa.

It should be noted that the process according to the invention can conveniently be implemented in devices used in conventional processes. These eos processes are therefore mainly divided into three decks. In the first section where the reaction takes place, the reactor is installed under pressure. In the second section ea separates the formed acid or ester thereof from Clastophin and evaporates the reaction mixture. The vaporized stream is then fed to the carboxylic acid purification section or its eater. The reaction phase remaining in the liquid form, containing mainly the catalyst, is recycled to the reactor.

According to a particular embodiment of the process according to the invention, the reaction process regularly cleans the corrosive metals it contains, in particular Seleso, aolybdan, back and nickel. This operation aa performs well-known means for those skilled in the art, for example, treating the reaction mixture or precipitating the catalyst and separating it from the corrosive metals by filtration.

The process according to the invention is suitable for producing any type of carboxylic acid or its eater containing at least two carbon atoms. H63e is thus used for the production of proponic acid from ethanol, succinic acid from ethylene oxide and adipic acid from 1,4-butanediol, as well as their eateries.

This epaa aa train is hired to obtain acetic acid and / or ethyl acetate with ethanol.

According to a preferred embodiment of the invention and in carrying out the process according to the invention, octethanol starts with ethyl iodide, ethyl acetate and acetic acid as the solvent.

The following are non-limiting examples of the invention.

DETAILED DESCRIPTION OF THE INVENTION

Example 1

The following tests were carried out in a continuous manner in an autoclave with a displacement of 300 _[ mu] l ₍ equipped with mechanical or reactive feeders).

The reaction mixture contains yellow chloride and a concentration of 3 eeol / L in acetic acid.

The feed of setanol, ethyl iodide and water is controlled accordingly. that the content of the individual components in the reaction mixture is maintained at the values given in Table 1.

The residence time in the autoclave is approximately 10 elnuts.

The total pressure in the autoclave is 3 HPa and the temperature is maintained at 190 C.

The reaction mixture exiting the autoclave is degassed and cooled.

Zaea and gases aa are analyzed by gas phase chromatography.

Table 1

Tests H.iO CBII CBaCOaB CBsCOaCBa Bwak activity A 6.6 9.7 96 26 11 = 4 600 B 6.7 7.7 60 26 11 4 700 C 6.9 9.2 61 27 10.6 4 800 D 6.8 3.6 61 27 9.3 4 600

B · · λ »n the desired carbonylation rate, expressed in aol / l.h.

The carbon monoxide consumption rate is obtained. This gas is also taken into account for the contribution of this gas to the production of carbon dioxide.

The activities correspond to the aols of the formed orthoic acid per aol.

The contents of the individual components of the reaction salt are expressed in terms of weight based on the total weight of the reaction saeal.

These tests show that the speed of carbonylation is substantially improved over that of the prior art disclosed in the prior art.

Example 2

The procedure was carried out according to the experimental procedure described in Example 1, but the composition of the reaction was as follows:

Table 2

Teatime Hjo CB .-. I CBaCOaB CBaCOaCBa Bkahb activity á 3.0 8.9 87 12 6.9 2 300 B 3.1 6.1 80 12 9.9 2 400 C 3.2 4.0 80 12 9.6 2 300

The units for each value are the same as those given in Table 1.

These teats prove that the rapidity of carbonylate remains high compared to the flared gradual use of alldlua, even at low water contents and without any catalyst precipitation.

Example 3

The procedure is as in the above examples.

The supply of water, ethyl iodide, ethanol and acetic acid is controlled so as to maintain the following compositions:

Table 3

Tests Hao Chaohu CBoCOdCffa CHaCOaH Chaxas Ir Bka ·· activity A 7.3 1.3 27 56 9.8 2,9 13 4 400 B 5.1 0.56 20 71 3.8 2,2 8,6 3 900 C 5.9 0.77 23 65 5.6 2.3 10.1 4 500 D 6.3 1.1 24.9 57.6 7.7 2,3 11,4 4 900

The contents of Iridium are expressed in aaol / 1.

The other values shall be expressed in the same units as shown in Table 1.

The H1 content of the reaction medium is in the range of 4 to 7 BBOI / L.

Example 4

The procedure is as in Example 1, except that the catalyst used is obtained from Ir (CO) and prepared as follows:

50 g of hydroiodic acid in solution at 57% concentration in water and 290 g of acetic acid are placed in a round bottom glass flask.

The mixture is heated to reflux for 4 hours under reflux and under air ataoafar.

The carbonylafin reaction is carried out in a continuous manner, at a rate of 1.9 aa / l Iridium coming from a highly sintered solution, while maintaining the composition of the reaction solution of:

1% water,

3.3 Ethyl iodide, ethyl acetate, the residue being acetic acid.

These liners achieve a carbonylate rate

4.3 aol / h-1r corresponding to the activity of 2,300 aols formed by cy. selins per eol Iridium for 1 hour and per liter.

The manure of produced proptonic acid is less than 23 g / kg of acetic acid produced.

The amount of formic acid produced is less than 25 g / kg of acetic acid produced.

Example 5

The carbonylation is carried out in the presence of a catalyst obtained with Ir 2 CO 3 by the same experimental procedure as in the above example, while maintaining the following deposition of the reaction mixture (B, expressed as haotnoate):

1.8 eaol / 1 iridium,

9.9 * water,

3,6 B of ethyl iodide,

Acetylacetate.

A carbonylation rate of 3.4 aol / h.l, corresponding to an activity of 3000 aols of acid formed per aol of Iridium and per liter is achieved.

The amount of proponic acid and formic acid formed is less than 25 g / kg of acetic acid produced.

Claims (8)

PATIIT 1 1 1 I I A process for producing carboxylic acids or their esters containing n + 1 carbon atoms by reacting carbon monoxide. in a liquid fusion containing one alcohol, containing no carbon atoms, in the presence of a catalytic sythate on the basis of phenylene iridium and a halogen-containing protector, characterized in that the water in the anosat is maintained in the reaction medium during the reaction. 10, a halogen-containing procoator in the 0 and? 10 V anosate ester corresponding to the aforementioned carboxylic acid and anophthalic alcohol 2 afi 40X, said carboxylic acid forming a solvent for the reaction. Process according to the above claim, characterized in that the water content of the reaction mixture is between 2 and 8 S. ABOUT Method according to any one of the preceding claims, A characterized in that the reaction mixture maintains the content of the halogen-containing promoter in the range of 1 to 6 H. The process according to any one of the preceding claims, characterized in that the reaction and the reaction is carried out maintaining the content of the above-mentioned eater in the range from 5 to 30 S. Method according to any one of the preceding claims, characterized in that it uses an alcohol derived from a saturated hydrocarbon and from 1 to 10 carbon atoms. A method according to any one of the preceding claims, characterized in that it uses a halogen-containing promoter comprising a halogen selected from chlorine, bromine or iodine, in combination and hydrogen, an alkyl group having 1 µl of 10 carbon atoms, acyl moieties and 1 µl and 10 µl. or an aryl moiety of 6 and 10 carbon atoms. A method according to the preceding claim, characterized in that it uses a halogen-containing promoter whose residue corresponds to that of the alcohol. Process according to any one of the preceding claims, characterized in that the acetic acid is produced by reacting netanol with carbon monoxide in the presence of water, methyl iodide / ethyl acetate, wherein acetic acid forms a solvent for the reaction.