DE2830841A1 - Carbonylation of alkanol to alkanoic acid and ester - using heterogeneous phthalocyanine catalyst with alkyl halide promoter - Google Patents

Abstract

Carbonylation of a lower alkanol with CO is carried out at 100-250 degrees C and 1-200 atmos. in presence of a catalyst system consisting of a Co, Rh or Ir phthalocyanine (I) plus an alkyl halide (II) as promoter. Where (II) does not contain a sulphonic acid or sulphonate substit. then a second promoter (III) is present i.e. a (cyclo)alkane-or arene- sulphonic acid, or an alkali(ne earth) or NH4 sulphonate. (II) is esp. CH3I and (III) toluene or benzene-sulphonic acid. Esp. (I) is sulphonated chlororhodium phthalocyanine or Rh (III) phthalocyanine tetrasulphonate. The prods. are esters and acids variously useful as solvents, intermediates for rubbers, plastics, pharmaceuticals, insecticides etc. Good yields are achieved in a continuous process using heterogeneous catalysts.

Description

The invention relates to a method for Carbony-

lation of alcohols. In particular, the invention provides an improved Process implementation for the carbonylation of alcohols, by the considerable Yields of the desired carbonylated products, i.e. carboxylic acids and their Esters, can also be achieved in a continuous flow of material can. Catalyst systems or catalysts are used in the process of the invention for use that are insoluble in the reactants and products, i.e. represent heterogeneous catalysts.

A number of carbonylated products, such as esters and acids, are important Chemicals for the chemical industry.

These products can be made from alcohols that are more readily available and are comparatively cheap starting materials. It is accordingly of great importance from the starting materials used in the process to achieve high yields of the desired products. Aliphatic esters are used for a variety of purposes. For example, methyl acetate is used as a solvent, in extracts, for fragrances, artificial leather, plastics, paint materials, varnishes and the like used. Similarly, ethyl propionate is used as a solvent for Cellulose ethers and esters, as diluents, for pyroxylin (cellulose nitrates), used in fruit syrups, etc., while propyl butyrate is used, for example, in mixed solvents for cellulose ethers is used. In addition, the acids, e.g. acetic acid, in various fields as acids, solvents, reactants the production of rubber, plastics, fibers, pharmaceutical substances, Dyes, Insecticides, photographic chemicals and as intermediates in manufacture used by anhydrides and esters. Propionic acid is used in the manufacture of propionates used, some of these compounds are found as shape inhibitors for bread, as Emulsifying agents, as solutions for the electroplating of nickel or in perfume esters, artificial fruit flavors or pharmaceutical substances application.

The invention is based on the object of a method for obtaining of carbonylated products using alcohols as starting materials and in particular to create a mode of operation that improves yields brings about the desired carbonylated products and still simple is to be carried out. In the method of the invention, an alcohol is mixed with carbon monoxide treated in the presence of a metal phthalocyanine catalyst and an acid compound.

In one embodiment of the invention, the process is for carbonylation of alcohols characterized in that the alcohol is mixed with carbon monoxide in the presence an activated metal phthalocyanine catalyst supported by a sulfonyl group and an alkyl halide is prototyped, treated at carbonylation conditions and the resulting carbonylated product wins.

According to a particular embodiment, the method according to the invention is for the carbonylation of alcohols, characterized in that one methyl alcohol with Carbon monoxide in the presence of a chloro-rhodium phthalocyanine catalyst, one Promoter compound comprising methyl iodide and toluenesulfonic acid at a temperature In the range of about 1000 to about 2500C and a pressure in the range treated from about 1 to about 200 atmospheres and the resulting products methyl acetate and acetic acid wins.

According to a further particular embodiment, this is according to the invention Process for the carbonylation of alcohols, characterized in that methyl alcohol with carbon monoxide in the presence of a chloro rhodium phthalocyanine tetrasulfonate catalyst and a promoter compound comprising methyl iodide at a temperature in the range from about 1000 to about 2500C and a pressure in the range from about 1 to about 200 Treated atmospheres and the resulting methyl acetate and acetic acid wins.

In the process of the invention, in particular, a heterogeneous one comes into play Catalyst (e.g. a chloro-rhodium phthalocyanine catalyst), which is produced by a sulfonic acid or sulfonate group (attached either to the phthalocyanine compound or to a added organic compound) and an alkyl iodide is promoted, for use. This enables the carbonylation of alcohols by treating an alcohol considerably improved with carbon monoxide.

Additional considerations and preferred actions are evident from the following further explanation of the invention.

According to the process of the invention for the carbonylation of alcohols can improve esters and acids using a heterogeneous Catalyst are generated. The carbonylation reaction occurs through treatment an alcohol with carbon monoxide in the presence of special catalysts, namely especially metal phthalocyanine compounds in which the metal is a transition metal the Group VIII of the periodic table, preferably the complexes of cobalt, Rhodium or iridium, the catalyst being the presence of a sulfonyl group and an alkyl halide is promoted. The carbonylation reaction is carried out at reaction conditions with temperatures in the range from about 1000 to about 2500C, preferably in the range from about 1500 to about 2000C, and pressures in the range from about 1 to about 200 atmospheres carried out.

Preferably the pressure under which the carbonylation reaction is carried out by the carbon monoxide present as one of the reactants brought about. On the other hand, however, the carbon monoxide can also only have a partial pressure contribute, then the difference to the total operating pressure by introduction a substantially inert gas, e.g., nitrogen, into the reaction zone will. Greater yields of the desired product are achieved when in the reaction zone Alkyl iodides are present. In the case of the alkyl iodides introduced into the reaction zone it can be aliphatic iodides, e.g. methyl iodide and its homologues, and aralkyl iodides, e.g. benzyl iodides. The iodides can also be put in place through implementation of the alcohol with added hydriodic acid.

Under the term "sulfonyl group", as it is used here, are sulfonic acid groups and sulfonate groups. To suitable sulfonic acids include alkane and cycloalkane sulphonic acids and arene sulphonic acids, e.g. methane sulphonic acid, Ethanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, naphthalenesulfonic acids and analog connections.

Suitable sulfonates include salts of sulfonic acids such as the alkali, Ammonium and alkaline earth salts, e.g. sodium methanesulphonate, ammonium p-toluenesulphonate and magnesium-2- Naphthalene sulfonate. Salts of heavier metals, e.g. Silver methanesulfonate can also be used, although not necessarily with equivalent results.

The sulfonyl function can be bound to the phthalocyanine nucleus, for example by using a metal phthalocyanine sulfonate as a catalyst. Alternatively it can be present in an added compound, e.g. as toluenesulfonic acid.

The. Metal phthalocyanine compounds used in the process of the invention are used as catalysts, include, as already mentioned, a metal phthalocyanine, in which the metal consists of a transition metal from group VIII of the periodic table, preferably made of cobalt, rhodium or iridium; consists. In making the Different metal phthalocyanine compounds can bond to different anions to the transition metal in the final catalyst composition.

The anions can be any negatively charged ion, that in the feed or precursor for the metal phthalocyanine compound is present.

For example, chlorine can be used in a rhodium phthalocyanine catalyst be present resulting from the feed comprising rhodium trichloride, so that the final catalyst then consists of chloro-rhodium phthalocyanine. to other elements in the anions, which are also used in the manufacture of the catalyst May come in include fluorine, bromine, iodine, phosphorus, sulfur, arsenic, nitrogen etc. Furthermore, various metal complexing agents can be added to the catalyst in the Reaction zone can be added, although not necessarily at the same time Results.

Some examples of such metal complexing agents are Arsine, Phosphines, alkyl and aryl phosphites and the like as examples of suitable catalyst compositions for carrying out the process of the invention may be mentioned: cobalt phthalocyanine, Rhodium phthalocyanine, iridium phthalocyanine, chlorrhodium phthalocyanine, chlorobalt phthalocyanine, Chloriridium Phthalocyanine, Cobalt Phthalocyanine Carboxylate, Chlorrhodium Phthalocyanine Carboxylate, Iridium phthalocyanine carboxylate, cobalt phthalocyanine tetracarboxylate, chlorrhodium phthalocyanine tetracarboxylate, Iridium phthalocyanine tetracarboxylate, cobalt phthalocyanine tricarboxylate, chlororhodium phthalocyanine tricarboxylate, Iridium phthalocyanine tricarboxylate, cobalt phthalocyanine dicarboxylate, chlororhodium phthalocyanine dicarboxylate, Iridium phthalocyanine dicarboxylate, and analogous compounds. If the sulfonic acid or sulfonate function is to be present in the phthalocyanine compound, for example the following compounds are used: cobalt phthalocyanine sulfonate, chlorrhodium phthalocyanine sulfonate, Iridium phthalocyanine sulfonate, cobalt phthalocyanine disulfonate, chlorrhodium phthalocyanine disulfonate, Iridium phthalocyanine disulfonate, cobalt phthalocyanine trisulfonate, chloro-rhodium phthalocyanine trisulfonate, Iridium phthalocyanine trisulfonate, cobalt phthalocyanine tetrasulfonate, chlorrhodium phthalocyanine tetrasulfonate, Iridium phthalocyanine tetrasulfonate and analogous compounds.

Alternatively, the phthalocyanine catalyst itself cannot contain a sulfonyl group have at its core but this group together with the catalyst in the form a separate compound, e.g. as p-toluenesulfonic acid.

Furthermore, other compounds that act as promoters for the catalyst compositions act, be present. Examples of such promotional compounds are called: alkyl halides, e.g. methyl iodide, ethyl iodide and propyl iodide, as well as less reactive alkyl halides such as for example methyl bromide, ethyl bromide, Propyl bromide, methyl chloride, ethyl chloride, propyl chloride and analogous compounds, as well as a weak inorganic acid, e.g.

Hydriodic acid. If desired, elemental iodine can also be used will. The catalyst of the type specified in detail above is in the Reaction mixture in an amount ranging from about 0.1% to about 20 percent by weight, based on the alcohol coming to the carbonylation.

The method of the invention can be used in any convenient manner carried out either in batch or in continuous operation will. For example, if a rudimentary operational implementation is used comes a batch of the alcohol and the catalyst in a suitable, pressure-resistant Device placed, e.g. in a shaking or stirring autoclave. Further be the promoter compound or compounds are also introduced into the reaction vessel. The latter is then sealed and pressurized with carbon monoxide and hydrogen brought to activate the catalyst. After activating the catalyst over a period of time ranging from about 0.5 up to about 4 hours or longer at temperatures in the range from about 500 to about 1000C, the gaseous products drained. Thereafter, the reaction vessel is again introduced by introducing carbon monoxide brought to the desired operating pressure and in the area for a period of time from about 0.5 up to about 20 hours or longer to a temperature in the range heated from about 1000 up to about 2500C. After finishing the desired Operating time, the heating is stopped and after the autoclave has cooled down The excess pressure is blown off at room temperature. The autoclave is then opened and the reaction mixture becomes taken. After separation from the catalyst the reaction mixture is subjected to conventional separation and purification measures, for example washing, drying, fractional distillation and the like., whereby the desired carbonylated products, i.e. an ester and an acid, of which The remainder of the reaction mixture can be separated off and recovered.

In the process of the invention, the reaction can also be carried out continuously Operating mode can be carried out.

The amount required for carrying out the process in this way of the alcohol is continuously fed to a reaction zone which has a metal phthalocyanine catalyst of the type indicated above. Alternatively, the metal phthalocyanine catalyst can be used on any inert support, e.g. carbon, alumina, silica, Zirconium oxide or the like., Are present. The catalyst in the reaction zone is beforehand by treatment with hydrogen and carbon monoxide in a similar manner, as explained above, has been activated. The remaining components of the Reaction mixture including the promoter compound or compounds and of the carbon monoxide are also fed continuously to the reaction zone, which are kept at the desired operating conditions in terms of temperature and pressure will. After flowing through the reaction zone for a predetermined period of time the reactor effluent is continuously withdrawn and conventional separation measures, analogous to the measures explained above. The products you want, i.e., the ester and the acid, are removed from any unreacted feedstocks separated and won. The unreacted input materials can lead to the Reaction zone can be recycled to form part of the feed.

As examples of esters and acids made by the method of the invention can be produced, may be mentioned: methyl acetate, ethyl propionate, propyl butyrate, Butyl valerianate, acetic acid, propionic acid, butyric acid, valeric acid and homologous Links.

The following examples and comparative experiments serve for further purposes Illustration of the process of the invention and that thereby in improved yields carbonylated products obtained, but the invention is not specific to these Implementation forms limited.

t Example 1 - Comparative experiment To illustrate the fact that the presence of promoters is required to achieve improved yields To achieve desired products, an experiment was carried out in which 100 g (3.1 mol) of methanol together with 0.10 g of chlorrhodium phthalocyanine in the glass insert a rotary autoclave. The autoclave was then closed and brought to an initial operating pressure of 90 atmospheres with carbon monoxide and heated to a temperature of 1740C. The autoclave and the reactants in it were held at this temperature for 4 hours; the maximum pressure during this Reaction time reached 190 atmospheres. After the 4 hour reaction period the heating was stopped and the autoclave allowed to cool to room temperature; the final pressure at room temperature was 90 atmospheres. After cooling to room temperature the overpressure was released and the autoclave opened. the analysis of the product by gas-liquid chromatography showed little or no Implementation had taken place; the majority of the withdrawn product existed from methyl alcohol.

In the above experiment from the interior of the glass insert withdrawn product was in an amount of 50g together with another amount placed in a second autoclave of 50 g of methyl alcohol. Furthermore were 2 g of hydriodic acid were added. The autoclave was sealed and filled with carbon monoxide brought to 60 atmospheres. The autoclave was then brought to a temperature of 0 175 C and held at this temperature for 16 hours; the maximum pressure at this temperature reached 143 atmospheres. After the 16-hour operating period the heating was stopped and the autoclave was allowed to cool to room temperature. The final pressure at room temperature was 53 atmospheres. The overpressure was released and the autoclave was opened. The analysis of the inside of the glass insert Product indicated that little or no reaction had occurred; the educated Amounts of acetic acid or methyl acetate were negligible.

Example 2 - Comparative test In this example, 60 g (1.9 Mole) of methanol together with 1 g of hydriodic acid and 0.11 g of chlorrhodium phthalocyanine placed in the glass insert of a rotating autoclave. The autoclave was closed and by injecting 70 atmospheres of carbon monoxide and 20 atmospheres of hydrogen brought to a pressure of 90 atmospheres. The autoclave was then brought to a temperature of 1700C and held at this temperature for 16 hours, the Maximum pressure reached 168 atmospheres at that temperature.

After the 16 hour operating period, the heating was stopped and the autoclave is allowed to cool to room temperature, the final pressure being this Temperature was 90 atmospheres. After releasing the excess pressure and opening the autoclave 27 g of a blue liquid with a black powder suspended from it won the inside of the glass insert. Analysis of this product showed that little or no implementation had taken place.

If the above experiment is repeated using 60 Atmospheres of carbon monoxide and 60 atmospheres of hydrogen the result was practical identical to the result of the previous experiment, i.e. it had little or no conversion took place and only negligible amounts of acetic acid were found and methyl acetate recovered.

Example 3 This example illustrates the promoter effect of a added compound containing a sulfonyl group. In this attempt were 51 g of methanol, 0.10 g of chlorohydium phthalocyanine, 0.15 g of p-toluenesulfonic acid and Place 1 g of hydriodic acid and 1 g of methyl iodide in the glass insert of a rotary autoclave brought in. The autoclave was sealed and filled with 80 atmospheres of hydrogen and pressurized carbon monoxide. The autoclave was then brought to a temperature heated from 800C and held for 8 hours at this temperature, with the maximum pressure reached 181 atmospheres during this period. After this trial period the heating was stopped and the autoclave was allowed to cool to room temperature. The overpressure was released and the autoclave was then using Carbon monoxide brought to 90 atmospheres pressure. After reaching the desired Operating pressure, the autoclave was heated to a temperature of 175 ° C and 8 hours kept at this temperature for a long time, with the maximum pressure at this temperature Reached 145 atmospheres. After the 8 hour trial period, the heating stopped finished and the autoclave allowed to cool to room temperature, the final pressure was 73 atmospheres at room temperature. The overpressure was blown off and the The autoclave was opened. The product in the glass insert was determined by gas chromatography analyzed; it contained 10 mole percent of a mixture of acetic acid and methyl acetate.

Although the mole percentage of carbonylated products is proportionate was small, it should be noted that the amount of catalyst used also was quite small and that by using a larger amount of catalyst a larger one Amount or higher yield of the desired products can be achieved.

Example 4 This example illustrates the promoter effect of Sulfonyl groups on the phthalocyanine nucleus. A mixture of 58 g of methyl alcohol with 0.014 Mole of methyl iodide, 0.016 mole of hydriodic acid and 0.37 g of sodium chlorrhodium phthalocyanine tetrasulfonate was placed in the glass insert of a rotating autoclave. The autoclave was sealed and pressurized with 80 atmospheres of carbon monoxide and 80 atmospheres of hydrogen. The autoclave was then heated to a temperature of 80 ° C. and for 16 hours held at this temperature. The maximum pressure during this period was 180 atmospheres. After the 16 hour trial period, the Heating stopped and the autoclave was allowed to cool to room temperature. Of the The final pressure at room temperature was 148 atmospheres. The overpressure was released and the autoclave was opened. There were 48 g of a clear liquid with a green-black powder sediment removed from the autoclave. The gas chromatographic Analysis showed that little or no conversion had taken place. Afterward 44 g of the product obtained from the glass insert were placed in a second autoclave introduced, which is then sealed and filled with carbon monoxide to a pressure of 90 atmospheres was brought. The autoclave was heated to a temperature of 200 ° C. and 16 Maintained at this temperature for hours. The maximum pressure during this period was 178 atmospheres. After the 16 hour trial period, the heating stopped finished and the autoclave allowed to cool to room temperature. The final pressure was 65 atmospheres. The overpressure was released and the autoclave was opened. 16 g of product were removed from the glass insert; it was about a blue-green liquid over a black powder. Analysis of this product found by gas chromatography to be 11 mole percent conversion to methyl acetate and a 9 mole percent conversion to acetic acid had occurred.

The fact that a conversion leads to the desired carbonylation products occurred, is due to the sulfonyl groups in the catalyst composition, i.e. the specified sulfonate.

Example 5.

In this example, methyl alcohol was prepared in a manner similar to that in subjected to the above examples of carbonylation by treatment of 41 g of methanol and 2.64 g of chlorrhodium phthalocyanine monosulfonate with 80 atmospheres of carbon monoxide and 80 atmospheres of hydrogen at one temperature of 800C over a period of 8 hours, using 1 g of methyl iodide as a promoter was present. After activating the catalyst in this way, the pressure was increased drained and the autoclave then repressurized to 90 with carbon monoxide Atmospheres. The autoclave was then heated to one temperature for 8 hours heated from 175 ° C. The maximum pressure reached 130 atmospheres. After the Heating and cooling the autoclave to room temperature was the final pressure at room temperature 50 atmospheres. The autoclave was opened and 34 g of reaction product in the form of a dark blue liquid with some additional dark granulate particles were removed and examined by gas chromatography. Analysis of this product found a 25 mole percent conversion to methyl acetate mixed with a smaller amount of acetic acid had taken place.

Example 6 In a similar manner to the previous examples 55.8 g of methyl alcohol and 2.0 g of cobalt phthalocyanine tetrasulfonate were combined with 3.2 g of methyl iodide and 2.0 g of toluenesulfonic acid in the glass insert of a shaking autoclave brought in. The autoclave was sealed and sealed by introducing 90 atmospheres Carbon monoxide pressurized.

The autoclave was then heated to a temperature of 1750C and Maintained at this temperature for 8 hours. The maximum pressure at this temperature reached 148 atmospheres.

After the 8 hour trial period, the heating was stopped, let the autoclave cool to room temperature and the pressure, 78 atmospheres, blown off. The autoclave was opened and there were 12 g of one dark blue liquid containing very dark blue particles in suspension taken from the glass insert. Analysis of the product by means of gas chromatography showed that a 5 mole percent conversion to methyl acetate and a 2 mole percent conversion to acetic acid had taken place.

Claims (15)

Process for the carbonylation of alcohols experience t for the carbonylation of alcohols, drawn by the fact that the alcohol with carbon monoxide in the presence of an activated metal phthalocyanine catalyst and promoters treated at carbonylation conditions and the resulting carbonylated product wins. 2. The method according to claim 1, characterized in that at Carbonylation conditions with a temperature ranging from about 1000 to about 2500C and a pressure in the range of about 1 to about 200 atmospheres. 3. The method according to claim 1 or 2, characterized in that the promoters have sulfonyl groups. 4. The method according to any one of claims 1-3, characterized marked, that the promoters comprise an alkyl halide. 5. The method according to claim 4, characterized in that the promoter consists of methyl iodide. 6. The method according to any one of claims 1 to 5, characterized in that that the metal phthalocyanine catalyst used is chlorrhodium phthalocyanine, which has a sulfonyl group contains, or a mixture of chlorrhodium phthalocyanine and an organic compound, containing a sulfonyl group is used. 7. The method according to any one of claims 1 to 5, characterized in that that rhodium (III) phthalocyanine is used as the metal phthalocyanine catalyst. 8. The method according to any one of claims 1 to 5, characterized in, that cobalt phthalocyanine is used as the metal phthalocyanine catalyst. 9. The method according to any one of claims 1 to 5, characterized in, that iridium phthalocyanine is used as the metal phthalocyanine catalyst. 10. The method according to any one of claims 3 to 9, characterized in that that a toluenesulfonic acid is used as a promoter. 11. The method according to any one of claims 3 to 9, characterized in that that benzenesulfonic acid is used as a promoter. 12. The method according to any one of claims 1 to 11, characterized in that that methyl alcohol is used as the alcohol and a mixture as the carbonylated product from methyl acetate and acetic acid wins. 13. The method according to any one of claims 1 to 11, characterized in that that one uses ethyl alcohol as the alcohol and a mixture as the carbonylated product from ethyl propionate and propionic acid. 14. The method according to any one of claims 1 to 11, characterized in that that propyl alcohol is used as the alcohol and a mixture as the carbonylated product from propyl butyrate and butyric acid. 15. The method according to any one of claims 1 to 5, characterized in that that the metal phthalocyanine catalyst is rhodium (III) phthalocyanine tetrasulfonate used.