GB2049673A

GB2049673A - Synthesis of Alcohols

Info

Publication number: GB2049673A
Application number: GB8010906A
Authority: GB
Original assignee: UOP LLC
Current assignee: Honeywell UOP LLC
Priority date: 1979-04-02
Filing date: 1980-04-01
Publication date: 1980-12-31
Also published as: IT1147333B; IT8021113A0; DE3012729C2; FR2453124A1; MX152374A; GB2049673B; DE3012729A1; BR8002015A; FR2453124B1

Abstract

Alcohols are synthesized by reacting an olefinic compound, carbon monoxide and hydrogen in the pressure of a Group VIII organometallic complex catalyst at reaction conditions, which usually include a temperature of from 50 DEG to 250 DEG C. and a pressure of from 10 to 300 atmospheres, in the presence of a promoter compound which is a nitrile or ammonia.

Description

SPECIFICATION Synthesis of Alcohols This invention relates to the synthesis of alcohols. More specifically, the invention is concerned with a process for synthesizing an alcohol, especially a primary alcohol, by reacting an olefinic compound, carbon monoxide and hydrogen in the presence of a catalytic composition and a promoter compound.

It is well known in the chemical art that alcohols, especially relatively long chain primary alcohols and low molecular weight alcohols, constitute an important class of compounds. For example, ndodecanol (lauryl alcohol) is an important intermediate in the preparation of synthetic detergents as well as lube additives, rubber, textiles and perfumes. Likewise, n-tetradecanol (myristyl alcohol) is a useful intermediate in the preparation of plasticizers as well as being used as an antifoam agent. an intermediate in the preparation of perfume fixitives for soaps and cosmetics, as well as being a base for the manufacture of wetting agents and detergents, while n-hexadecanol (cetyl alcohol) is used as an intermediate for the preparation of compounds useful in perfumes, emulsifiers and cosmetics.Butanol is utilized fn the preparation of esters such as butyl acetate and as a solvent for resins and coatings, as well as in plasticizers, detergent formulations, dehydrating agents and hydrauiic fluids.

This invention seeks to provide an improved process for synthesizing alcohols utilizing relatively inexpensive starting materials.

According to this invention there is provided a process for the production of an alcohol which comprises reacting an olefinic compound, preferably an olefinic hydrocarbon, carbon monoxide and hydrogen in the presence of a Group VIII organometallic complex catalyst and a nitrile promoter or ammonia promoter and recovering the resulting alcohol.

In a preferred embodiment of this invention undecene, carbon monoxide and hydrogen are reacted in the presence of chlorodicarbonylrhodium dimer and succinonitrile or an organometallic complex catalyst based on rhodium chloride and aqueous ammonia at a temperature of from 50C to 2500C. and a pressure of from 10 to 300 atmospheres, and the resulting dodecanol is recovered.

Reaction conditions employed to produce the desired results generally include a temperature of from 50 to 2500C. and a pressure of from 10 to 300 atmospheres. The preferred pressure is the autogenous pressure resulting from the presence of hydrogen and carbon monoxide in the reaction mixture. However, it is also contemplated that the pressure resulting from the use of hydrogen and carbon monoxide can comprise only a partial operating pressure, the remainder being provided for by the introduction of a substantially inert gas such as nitrogen, helium, or argon into the reaction vessel.

Other suitable reaction conditions include a mole ratio of hydrogen to carbon monoxide of from 0.1:1 to 5:1 and a mole ratio of olefinic compound to catalyst of from 500:1 to 200:1. Whether using an ammonia promoter or nitrile promoter, a mole ratio of ammonia to catalyst of from 50:1 to 300:1 is desirable.

The olefinic compound is preferably a hydrocarbon. Examples of olefinic hydrocarbons which may be employed in the process of this invention include straight chain and branched chain olefins containing from 3 to 30 carbon atoms such as propylene, and the isomeric butenes, pentenes, hexenes, heptenes, octenes, nonenes, decenes, u ndecenes, dodecenes, tridecenes, tetradecenes, pentadecenes, hexadecenes, heptadecenes, octadecenes, nonadecenes, eicosenes, henicosenes, docosenes, tricosenes, tetracosenes, pentacosenes, hexacosenes, heptacosenes, octacosenes, nonacosenes and triacontenes; cyclic olefinic compounds having the olefinic bond in the ring or a side chain such as cyclopentene, cyclohexene, cycloheptene and styrene; and dienes such as 1 3-butadiene, 1,3-pentadiene, 1 ,3-hexadiene, 2,4-hexadiene, 1,3-heptadiene and 2,4-heptadiene.

The reaction between the olefinic compound, carbon monoxide and hydrogen is effected in the presence of a catalyst comprising a Group VIII organometallic complex. Preferably, the metallic portion of the catalyst is selected from rhodium, ruthenium and cobalt, representative examples of materials which may be provided to form the catalysts comprising the metals, nitrates, halides, halocarbonyls, organometallic complexes, oxides or carbonyl complexes.Specific examples of the compounds which may be employed to provide the catalyst include rhodium, rhodium nitrate, rhodium chloride, rhodium bromide, rhodium iodide, rhodium fluoride, rhodium acetate dimer, rhodium oxide, chlorodicarbonylrhodium dimer, rhodium carbonyl, chlorobis(ethylene)rhodium dimer, hexarhodiumhexadecylcarbonyl, tetrarhodiumdodecylcarbonyl, chlororhodiumcarbonyl dimer, hydridorhodiumtris(trimethylphosphine)carbonyí, hydridorrhodiumtris(tri-n-butylphosphine)carbon hydridorhodiumtris(triphenylphosphine)carbonyl, hydridorhodiumtris(trimethylphosphite)carbonyl, hydridorhodiu mtris(triethylphosphite)carbonyl, hydridorhodiumtris(triphenylphosphite)carbonyl, rhodium acetylacetonate, ruthenium, ruthenium nitrate, ruthenium chloride, ruthenium bromide, ruthenium iodide, ruthenium fluoride, dichlorotricarbonylruthenium and rutheniumcarbonyl, organometallic complex catalysts being formed in situ from the materials added in other forms. It is to be understood that the aforementioned organometallic complexes are only representative of the class of compounds which may be employed, and that the present invention is not limited thereto. Cobalt is another Group VIII metal which may be used.

In addition to utilizing the catalyst of the type hereinbefore set forth in greater detail, the reaction between the olefinic compound, carbon monoxide and hydrogen is effected in the presence of a promoter which is a nitrile compound or ammonia. The nitrile compounds which can be used include alkyl nitriles, alkyl dinitriles, alkenyl nitriles, and aromatic nitriles.Specific examples of these compounds include acetonitrile (methyl cyanide), propionitrile (ethylcyanide), butyronitrile (propyl cyanide), undecyl cyanide, dodecyl cyanide and tridecyl cyanide; oxalonitrile, malononitrile, succinonitrile, suberonitrile and axelonitrile; acrylonitrile, crotononitrile, isocrotononitrile, tiglonitrile and angelonitrile; benzonitrile, 2-methylbenzonitrile, 3-methylbenzonitrile and 4-methylbenzonitrile; as well as substituted nitriles such as dimethylacetonitrile, diethylacetonitrile, diphenylacetonitrile, dimethylsuccinonitrile, diethylsuccinonitrile and diphenylsuccinonitrile. It is to be understood that the aforementioned nitrile compounds are only representative of the class of nitriles which may be employed as promoters, and that the present invention is not limited thereto.

When the reaction between olefinic compound, carbon monoxide and hydrogen is effected in the presence of a promoter comprising ammonia, the ammonia which is utilized as the promoting agent in the process of this invention may be used in either gaseous, liquefied or aqueous form depending to some extent on the reaction parameters of temperature and pressure which are employed. When utilizing ammonia as an aqueous solution, the ammonia may be present in a concentration of from 1 0% to 95% or more by weight, the preferred amount being about 30% by weight of the solution.

The process of this invention may be effected in any suitable manner and may comprise either a batch or continuous type of operation. When a batch type of operation is used it may be carried out as follows: A quantity of the olefinic compound, the Group VIII organometallic complex catalyst and the nitrile promoter or ammonia promoter are placed in an appropriate pressure resistant apparatus such as an autoclave of the rotating, rocking or mixing type. After placing the components of the reaction in the autoclave, it is then sealed and hydrogen and carbon monoxide are charged thereto until the desired operating pressure has been attained.Alternatively, if higher pressures are to be employed a portion of the pressure may be afforded by the introduction of a substantially inert gas into the reaction zone After reaching the proper operating pressure, the apparatus is then heated to the desired operating temperature which may range from SOC to 2500C. and maintained thereat for a predetermined residence time which may range from 0.1 to 10 hours or more in duration. Upon completion of the desired residence time, heating is discontinued and the apparatus and contents thereof are allowed to return to room temperature. Upon reaching room temperature the pressure is discharged, the apparatus is opened, and the reaction mixture is recovered therefrom.After separation from the catalyst, the reaction mixture may be subjected to conventional means of separation whereby the desired alcohol is separated from any unreacted starting material, promoter and/or unwanted side reaction products which may have formed, and recovered. A particular advantage which may be obtained when utilizing the process of the present invention is that the catalysts which are employed to effect the reaction are easily recovered as distillation bottom products and may be recycled for reuse.

In addition another advantage which is present is that the loss of products in the distillation step is relatively low inasmuch as alcohols do not polymerize readily and may therefore be recovered in an excellent yield.

It is also within the scope of this invention for the synthesis of alcohols to be accomplished by utilizing a continuous method of operation. When utilizing this type of operation it may be carried out as follows: The olefinic hydrocarbon is continuously charged to a reaction zone which is maintained at the proper operating conditions of temperature and pressure and which contains a catalyst of the type hereinabove set forth as well as the nitrile promoter or ammonia promoter. Alternatively, the nitrile promoter or ammonia promoter may also be continuously charged to the reaction zone either separately or along with the olefinic hydrocarbon charge. In addition to the continuous charging of the reactant to the operating zone, hydrogen and carbon monoxide either separately or in admixture are also charged thereto.Upon completion of the desired residence time in the reaction zone, the reactor effluent is continuously withdrawn and subjected to conventional means of separation, such as fractional distillation, whereby the desired alcohol is separated from unreacted starting materials and/or undesired side reaction products which may have formed, and recovered, while the unreacted starting materials may be recycled to the reaction zone to form a portion of the feed stock.

Examples of alcohols which may be synthesized according to the process of the present invention include primary alcohols such as ethanol, propanol, butanol, pentanol, tridecanol, tetradecanol, pentadecanol, hexadecanol, heptadecanol, octadecanol, nonadecanol and eicosanol. It is to be understood that the aforementioned alcohols are only representative of the compounds which may be synthesized, and that the present invention is not limited thereto.

The following examples are given to illustrate the process of the present invention.

Example I (Comparative) As an illustration of the need for a promoter comprising a nitrile compound, an experiment was performed in which 0.0283 gram of a catalyst comprising chlorodicarbonylrhodium dimer was placed in the glass liner of an 850 cc rocking autoclave. Thereafter 26.42 grams of undecene was placed in the autoclave, the autoclave was sealed and 1:1 mole ratio mixture of carbon monoxide and hydrogen was charged to the autoclave until 1 50 atmospheres of the blend gas had been added. The autoclave was then heated to a temperature of 1 500C. and maintained thereat for a period of 3 hours. During this time period the pressure in the autoclave fell from 181 atmospheresto 158 atmospheres. At the end of the 3 hour period, heating was discontinued and the autoclave was allowed to return to room temperature.Upon reaching room temperature the excess pressure was discharged, the autoclave was opened and the reaction mixture was recovered. Analysis of the product by means of gas liquid chromatography disclosed that there had been a 100% conversion of the undecene with a product selectivity comprising 20% dodecanol and 76% dodecanal.

Example II In this example 0.0315 gram of chlorodicarbonylrhodium dimer and 26.53 grams of undecene along with 1.83 grams of succinonitrile were placed in the glass liner of a rocking autoclave, the molar ratio of succinonitrile to rhodium being 146:1. The autoclave was sealed and a blend gas comprising a 1:1 mole ratio of carbon monoxide and hydrogen was charged thereto until a pressure of 1 50 atmospheres was reached. The autoclave was heated to a temperature of 1 500C. and was maintained at that temperature for a period of 3 hours, the pressure during this time dropping from 1 65 to 1 58 atmospheres. At the end of the 3 hour period heating was discontinued and after the autoclave had returned to room temperature, the excess pressure was discharged.After recovery of the reaction mixture, it was subjected to gas liquid chromatography which disclosed that there had been a 1 00% conversion of the undecene. In contradistinction to the previous experiment in which no nitrile was present at a promoter, the product selectivities rose to an 81% selectivity to dodecanol with only a 16% product selectivity to dodecanal.

Example III The experiment described in Example II above was repeated using 0.0262 gram of chlorodicarbonylrhodium dimer, 26.5 grams of undecene and 2.42 grams of adiponitrile. After sealing the autoclave, a blend gas comprising a 1:1 mole ratio of carbon monoxide and hydrogen was charged to the autoclave until an initial operating pressure of 1 50 atmospheres was reached. The autoclave was then heated to a temperature of 1 500C. and maintained thereat for a period of 3 hours, the pressure during this time dropping from 1 99 atmospheres to 1 80 atmospheres. After discontinuing the heating and allowing the autoclave to return to room temperature, the excess pressure was discharged and the reaction mixture was recovered.Gas liquid chromatographic analysis of the reaction product determined that there had been a 100% conversion of the undecene, the product containing a 78% selectivity to dodecanol and a 1 5% product selectivity to dodecanaI.

When the above experiment was repeated using benzonitrile, diphenylacetonitrile, and acetonitrile as the promoting agents, it was determined by analysis that in each instance there had been a 1 00% conversion of the undecene while the product selectivity to dodecanol comprised 56%, 44% and 25% respectively, the product selectivity to aldehydes being 41%, 51.5% and 72% respectively.

Example IV To determine an optimum mole feed ratio of nitrile to the metallic portion of the catalyst, a series of experiments were performed in which the molar ratio of nitrile to rhodium varied from 0:1 (Comparative) to 505:1. As in the previous experiments, all runs were made at a temperature of 1 500 C. using chlorodicarbonylrhodium dimer as the catalyst, succinonitrile as the nitrile promoter and 1 50 atmospheres of a 1:1 carbon monoxide-hydrogen blend gas. The runs were made during a period of 3 hours in a rocking autoclave. Gas liquid chromatographic analysis of the reaction product which was recovered at the end of this run determined that there had been a 100% conversion of the undecene in all instances. Table I below illustrates the effect of the varying mole ratio of nitrile promoter to rhodium catalyst.

Table I Nitrile/Rhodium Product Selectivities, % Mole Ratio Dodecanol Dodecanal 0 20 76 16 64 31 144 81 16 229 81 16 505 86 9 Example V In this example a series of runs were performed to illustrate the effect of temperature with and without the presence of a nitrile promoter. As in the previous experiments, about 26.5 grams of undecene were reacted in the presence of a chlorodicarbonylrhodium dimer catalyst which was present in an amount of about 0.027 gram. In each instance the runs were performed under 200 atmospheres of a 1:1 carbon monoxide/hydrogen blend gas for a period of 3 hours in an autoclave, the temperature varying from 1 50 to 2000 C. Two of the runs were made in the absence of a nitrile promoter while two runs were made in the presence of about 2 grams of succinonitrile.The results of these runs are set forth in Table II below.

Table II Nitrile/Rhodium Reactor Undecene Product Selectivities Molar Ratio Temp OC Conversion, % Dodecanol Dodecanal 0 150 100 20 76 0 200 91 8 85 229 150 100 81 16 163 200 98 94 1 It is therefore readily apparent from a review of this table that the presence of a nitrile promoter in the reaction system contributed greatly to an increase in the production of alcohols from undecene as compared to the production of aldehydes.

Example VI In a manner similar to that set forth in the above examples, rhodium chloride (which forms an organorhodium complex catalyst in situ) may be placed in a rotating autoclave along with a charge stock comprising a mixture of octenes. A promoter compound comprising adiponitrile in an amount sufficient to maintain an adiponitrile/rhodium molar ratio of 171:1 may also be placed in the autoclave which is thereafter sealed. A blend gas comprising a 1:1 mole ratio of carbon monoxide and hydrogen may also be charged to the sealed autoclave until an initial operating pressure of 1 50 atmospheres is reached. Thereafter the autoclave may be heated to a temperature of 2000 C. and maintained thereat for a period of 3 hours, at the end of which time heating may be discontinued and the autoclave allowed to return to room temperature.After returning to room temperature the excess pressure may be discharged and the autoclave opened. The reaction mixture may then be subjected to gas liquid chromatographic analysis to determine the conversion of the octenes and the obtention of nonanol in a relatively high product selectivity.

Similar experiments using heptene, docosene and butene as a charge stock for reaction with carbon monoxide and hydrogen in the presence of a rhodium, ruthenium or cobalt containing organometallic complex and in the presence of various nitrile promoters such as benzonitrile may also result in obtaining the corresponding alcohols, namely, octanol, tricosanol, and pentanol, and relatively high percentages of product selectivities.

Example VII In this example 0.0291 gram of a catalyst comprising chlorodicarbonylrhodium dimer was placed in the glass liner of a rotating autoclave. In addition, 30.03 grams of undecene and 0.406 gram of ammonia in the form of a 29.91 wt.% aqueous ammonia solution (1.5 cc) were also placed in the autoclave. The autoclave was then sealed and a 1:1 mixture of carbon monoxide and hydrogen was charged to the autoclave until 1 50 atmospheres of the blend gas had been added. The mole ratio of undecene to rhodium was 1176:1 and the mole ratio of ammonia to rhodium was 165:1. The autoclave was then heated to a temperature of 1 500 C. and maintained in a range of from 1 50 to 1 520C. for a period of 3 hours, the operating pressure during this time being 1 76 atmospheres.At the end of the 3 hour period heating was discontinued and the autoclave was allowed to return to room temperature. Upon reaching room temperature the excess pressure was discharged and the reaction mixture was recovered from the autoclave. Analysis of the product by means of gas liquid chromatography and elementary analysis disclosed that there had been a 1 to% conversion of the olefin with a 54.3% selectivity to the alcohol, dodecanol, a 3.7% selectivity to the alkane and a 42% selectivity to a mixture of undecyl amines.

Example VIII In this example the above experiment was repeated using an 850 cc rotating autoclave in place of the 300 cc rotating autoclave which was used in Example VII. The reaction mixture comprised 30.09 grams of undecene, 0.0282 gram of chlorodicarbonylrhodium dimer and 0.374 gram of ammonia which was added as a 29.91 wt.% aqueous ammonia solution. After sealing the autoclave, a 1:1 mixture of carbon monoxide and hydrogen was charged to the autoclave until 1 50 atmospheres had been added. The mole ratio of undecene to rhodium was 1229:1 and the mole ratio of ammonia to rhodium was 156:1. The autoclave was then heated to a temperature of 1500 C. and maintained in a range of from 1500 to 1 530C. for a period of 3 hours, the operating pressure during this period ranging from 196 to 1 99 atmospheres. At the end of the 3 hour period, heating was discontinued and after the autoclave had returned to room temperature the excess pressure was discharged. The autoclave was then opened and the reaction mixture, after recovery therefrom, was analyzed by means of gas liquid chromatography. This along with elementary analysis showed that there had been a 100% conversion of the undecene. As in the previous example, no aldehydes were formed but there was a 71.1%.

selectivity to dodecanol, a 3.4% selectivity to the alkane and a 25.5% selectivity to a mixture of undecy amines.

Example IX The above experiments were repeated using a 300 cc rotating autoclave, 0.0291 gram of chlorodicarbonylrhodium dimer, 30.05 grams of undecene and 0.383 gram of ammonia which was added as an aqueous ammonia solution. After sealing the autoclave, only 80 atmospheres of a 1:1 blend gas of carbon monoxide and hydrogen was charged to the autoclave. The autoclave was then heated to a temperature of 1 500C. and maintained thereat for a period of 3 hours, the operating pressure during this period dropping from 123 atmospheres to 120 atmospheres.After recovery of the reaction mixture, analysis disclosed that there had been only a 29% conversion of the undecene with a 1 9.4% selectivity to dodecanal, 62.8% selectivity to dodecanol, 1.6% selectivity to the alkane and 16.1% selectivity to a mixture of undecyl amines.

It is apparent from a comparison of Example IX with Examples VII and VIII lhat the higher operating pressures which are afforded by the introduction of a greater amount of blend gas will permit the higher conversion of the olefin and retard the formation of the undesired aldehyde product.

Example X (Comparative) To illustrate the necessity for the presence of an ammonia promoter in order to obtain an alcohol as the desired product, another experiment was performed in which 0.031 gram of chlorodicarbonylrhodium dimer and 29.96 grams of undecene were placed in the glass liner of an 850 cc rotating autoclave. After sealing the autoclave 1 50 atmospheres of a 1:1 mole ratio blend gas of carbon monoxide and hydrogen was charged thereto. The mole ratio of undecene to rhodium was 1096:1.

The autoclave was then heated to a temperature of 1500C and maintained in a range of 1500 to 15300. for a period of 3 hours, the operating pressure during this period dropping from 211 atmospheres to 205 atmospheres. Upon completion of the reaction period heating was discontinued and the autoclave was allowed to retum to room temperature. After discharging the excess pressure the autoclave was opened and the reaction mixture was recovered therefrom. The mixture was analyzed by means of gas liquid chromatography and elementary analysis which disclosed that there had been a 100% conversion of the undecene. í However, in contradistinction to the examples which utilized an ammonia promoter the analysis showed an 81.3% selectivity to aldehyde, dodecanal, with only a 17.8% selectivity to the alcohol, dodecanol.It is therefore readily apparent that by utilizing ammonia as a promoter for the reaction, it is possible to obtain a one-step synthesis of alcohols from olefins in which the desired product, namely, the alcohol, comprises a major product which may be readily separated from any other side reaction products.

Example Xl In a manner similar to that set forth in the above examples, a mixture comprising octene, ammonia in the form of an aqueous solution and rhodium chloride (which forms an organorhodium complex catalyst in situ) may be placed in an autoclave which is sealed. Thereafter a blend gas of carbon monoxide and hydrogen in a 1:1 mole ratio may be charged thereto until an initial operating pressure of 1 50 atmospheres is reached. Thereafter the autoclave may be heated to a temperature of about 1 500C. and maintained at this temperature for a period of 3 hours. At the end of this time heating may be discontinued and the autoclave allowed to return to room temperature. After returning to room temperature the excess pressure may be discharged and the autoclave opened. The reaction mixture may then be subjected to gas liquid chromatography and elemantary analysis to determine the presence of the desired alcohol, namely, nonanol.

In like manner, the olefins comprising heptene, docosene and butene may be subjected to a onestep synthesis reaction in the presence of organometallic complex catalysts formed from materials such as ruthenium black, chlorodicarbonylrhodium dimer, and rhodium chloride and also in the presence of ammonia in aqueous or liquefied form and also in the presence of a blend gas comprising a 1:1 mole ratio of carbon monoxide and hydrogen at operating conditions which include a pressure of about 1 50 atmospheres and a temperature of about 1 5000. to form alcohols such as octanol, tricosanol and pentanol.

Claims

1. A process for the production of an alcohol which comprises reacting an olefinic compound, carbon monoxide and hydrogen in the presence of a Group VIII organometallic complex catalyst and a nitrile promoter or an ammonia promoter and recovering the resulting alcohol.

2. A process as claimed in claim 1 in which the reaction is carried out at a temperature of from 500 to 2500C. and a pressure of from 10 to 300 atmospheres.

3. A process as claimed in claim 1 or 2 in which the catalyst is a rhodium or ruthenium organometallic complex catalyst.

4. A process as claimed in claim 3 in which the Group VIII metal for the catalyst is provided in the form of rhodium chloride, chlorodicarbonylrhodium dimer or ruthenium black.

5. A process as claimed in any of claims 1 to 4 in which the promoter is succinonitrile, adiponitrile or benzonitrile.

6. A process as claimed in any of claims 1 to 4 in which the promoter is gaseous ammonia, liquefied ammonia or ammonia in aqueous solution.

7. A process as claimed in any of claims 1 to 6 in which the molar ratio of promoter compound to catalyst is from 50:1 to 300:1.

8. A process as claimed in any of claims 1 to 7 in which the pressure is in excess of 125 atmospheres.

9. A process as claimed in any of claims 1 to 8 in which an olefinic hydrocarbon is reacted.

10. A process as claimed in claim 9 in which the olefinic hydrocarbon is undecene, octene, heptene, docosene or butene, and dodecanol, nonanol, octanol, tricosanol or pentanol, as the case may be, is produced.

11. A process for the production of an alcohol as claimed in claim 1 carried out substantially as described in any of the foregoing Examples II to IX or Xl.

12. Alcohols when produced by a process as claimed in any of claims 1 to 11.