CS213974B1 - Method of cobalt removal of products of unsaturated compounds hydroformylation - Google Patents

Abstract

The present invention relates to theology petroohemiokého procedure. The method according to the invention consists in that of hydroformylase unsaturated products compounds containing carbonyl Cobalt, acts by gas at elevated temperature and then cobalt salts are removed. The gas used is CO2 or gas with a COg content of 1 to 50 mol CO2 per mole of CO and prooes are carried out at temperatures 20 to 220 ° C, preferably 40 to 140 ° C, at pressures of 0.1 to 0.4 MPa. Cobalt formed the salt is removed from one of the usual ones by methods such as filtration, decahydopa or evaporating the aldehyde-containing product.

Description

The present invention relates to a process for the decobaltization of hydroformylated products of unsaturated compounds in the field of petro-chemical synthesis.

Hydroformylated products of unsaturated compounds, such as aldehydes, alkanols and other compounds containing oxygen, have wide application in many fields of economy and technology. The major part of these products is at that time necessary for the production of plasticizers, flotation agents, myoids and solubilizers.

The hydroformylated unsaturated compounds proceed at elevated temperature under the pressure of the synthesis gas CO + H ₂ in the presence of a cobalt catalyst (cobalt carbonyl). The hydroformylation product contains the final oxygen-containing compounds, hydroformylation by-products, an organic solvent, unreacted unsaturated starting compounds, as well as cobalt carbonyl. The cobalt catalyst should be separated from the hydroformylated products and returned to the hydroformylation loop to ensure the purity of the isolated end product and, moreover, this is important for reasons of economy. De-cobaltization of the hydroformylation products determines the oxosynthesis technology and the consumption of cobalt compounds is regarded as the main value of the technical state of the process.

During decobalting, cobalt carbonyls are separated from hydroformylation products either in the form of thermally unstable carbonyl, or as non-carbonyl compounds of cobalt and cobalt free from hydroformylation products, as appropriate, converted into alkanols or condensed aldehydes.

The main requirements to be metallized are the completeness of the recovery of the catalyst, as well as the suppression of by-reactions, such as oxydation, condensation and esterification of the end products of hydroformylation (aldehydes, alkanols and oxygen-containing compounds).

Incomplete separation of the cobalt catalyst can lead to contamination of the hydroformylated products with colored compounds, as well as to the deposition of cobalt on the reaction apparatus and on the pipeline, causing difficulties in technology and requiring additional process steps.

Methods are known to decobalt products of olefin hydroformylation products to obtain the carbonyl form of the catalyst. For example, treatment with a strongly basic medium on cobalt carbonyl solutions in the presence of CO and H ₂ , under pressure and at elevated temperature, produces a cobalt carbonyl salt that is water soluble and insoluble in organic medium. The salt is then treated with 5% sulfuric acid solution at atmospheric pressure. The obtained hydrocarbonyl is treated with a solvent or entrained with synthesis gas, absorbed by olefin and fed to the reactor (FR Patent 1,223,381, 1960} US Patent 3,763,247, 1968} GB 1,228,348).

Such a process is complicated with respect to the theological device and is associated with the use of waste water containing mineral salts.

Methods of thermally decomposing cobalt carbonyl by which the hydroformylation catalyst decomposes at elevated temperature to powdered co213974 balts are known (SU Patent Specification 247 247, 1965} 246 633, 1965). Various embodiments of these methods have the following disadvantages: difficulty in preventing cobalt from settling on the wall of the device; difficulty in separating cobalt from final products; the need to keep the prooes discontinuous, ie out of fashion; erosion of equipment life.

There are also known decobalting methods which rely on the treatment of hydroformylation products with mineral acids or strong organocarboxylic acids. (V.M. Gavrilova and J., Chlmlčeskaja premyšlenost, 1974, No. 10, p. 19). According to the process disclosed in DE 977 576, the product is hydrolyzed at 65 to 65 ° C and at atmospheric pressure with a 1 to 10% acid solution. The mixture of aldehyde and aqueous phase containing cobalt is separated in the settling zone. Aqueous solutions of the cobalt salt are converted into cobalt forms suitable for introduction into the hydroformylation reactor.

This method places high demands on the material of the hydroformylation and decobalting plant, since the acids are corrosively active, additional process steps are required, and moreover, this method is associated with wastewater pollution.

There are known methods of de-cobaltizing by the action of oxidizing acids which rely on the conversion of cobalt carbonyl in the salt in the presence of an oxygen source (air, 0 ₂ , Η ₂ θ2 'P ^eroxld ^) ·

The direct treatment of the oxygen-containing gas with the hydroformylation product can convert the cobalt dissolved therein into a cationic form. The acids which serve as the source of anions are introduced separately or liberated in the production of the cobalt-catalyzed active cobalt forms from CO (00CR) ₂ . The oxidation prooes are carried out at a temperature of 20 to 60 ° C under a pressure of 1 to 40 bar, the oxidation time being a few seconds to 60 minutes. The amount of oxidizing agent is over 1 mole of active oxygen per mole of cobalt. The resulting cobalt salts and acids are separated from the product according to one of the following methods:

separation in the form of an aqueous solution, filtration of the sediment, separation of oil-soluble copalt salts in the form of a muddy product by distillation, selective extraction of the cobalt salt with a boiling solvent (see, for example, U.S. Patent 1,377,920, 1964, DE)

272, 911, 1966; SU Patent Specification 169 103, 1961, Organio Syntheses via Metal Carbonyls, v.l., N.Y.-London-Sydney, 1968, publ. J.Wender,

P. Plno).

Under the action of oxygen on the cobalt carbonyls, oxidation of the aldehydes to the acids takes place, as well as the formation of esters from the alkanols and the acids, if any, introduced. Increasing the acid and ester concentrations in hydroformylation products leads to reduced yields of the end product, complicating the separation stages of aldehydes or alkanols from mixtures containing acids having a boiling point close to the boiling point of aldehydes or alkanols. against acids *.

The amount of by-products depends on the excess oxygen per mole of cobalt, the cobalt content, the prooes temperature as well as the structure, and the molecular weight of the aldehyde *

Furthermore, a process is known (SU patent 169 103) in which the hydroformylation product of olefins is treated with oxygen at 20 to 80 ° C in the presence of naphthenic acids. The cobalt carbonyl is converted in a thermostable, freely soluble form of cobalt naphthenate. aldehydes, a solvent, and a portion of by-products. The destllaol residue contains cobalt naphthenate and returns to mainstream *

The disadvantage of the process lies in the formation of acids from oxoaldehydes. For example (KA Aleksejeva in the Collection of Butyraldehydes and Butyl Alcohols Polyohsmle maslyanyh aldegidov 1 butlloryoh splrtov, 1977, Tl pp. 76-85, Leningrad, VINEIECHTECHIM) is used in the oxldaol product of catalytic propylene hydroformylation containing 0.2 wt. 4 Co and 70 wt. <f> butylaldehyde (at a content of 0 ₂ 2 mol per mol Co and a temperature of 60 ° C), oxidizes 0.5 to 1.5 wt. %, based on butyraldehyde and in the case of oxldaol, from the same catalytic hydroformylate dodeoene under the same conditions, 1.5 to 5.0 wt.

Increasing the concentration of acids corresponding to yldehyde in hydroformylation products reduces the advantages of oxidation decobalting methods and makes it preferable to more complicated methods that ensure less by-product formation.

SUMMARY OF THE INVENTION It is an object of the present invention to select a participant of the reaction to decompose the cobalt carbonyls contained in olefin hydroformylation products to obtain a high end product under mild conditions and by changing the rheological parameters, and to simplify the rheological process by reducing the formation of by-products (acids) as well as removing operations to separate them.

This object is solved by the method according to the invention odkobaltování product hydroformylaoe nenasyoenýob compounds via decomposition of a catalyst and in the gas, followed by removal of cobalt salts according to the invention is used as gas C0 ₂ or a gas containing C0 ₂ in an amount of 1-50 mol C0 ₂ per 1 mol of Co, at a temperature of 20 to 220 ° C, at pressures of 0.1 to 0.4 MPa.

It is expedient to carry out the process at temperatures not exceeding 140 ° C, because at higher temperatures and insufficient agitation, the cobalt carbonyls may decompose and not at temperatures below 40 ° C, because at lower temperatures the oxidation rate decreases and the volume of the reaction apparatus increases.

The cobalt salt obtained is generally removed from the product containing the aldehydes by methods known per se, for example by filtration, decantation or evaporation.

The process according to the invention is carried out as follows.

The product of catalytic hydroformylation of unsaturated compounds containing car _2; P ₉ 7 _{4 4} ..... 'carbonyl cobalt, the final product as aldehydes and alkanols produktyhydrofořmylační side reactions as well as a solvent (organic solvent or high boiling reaction products), the decomposition of cobalt carbonyls is introduced into the reactor and a pressure of 0 06 to 0.5 bar, preferably 0.1 to 0.4 MPa at a temperature of 20-220 ° C, preferably 40-140 ° C, treated with C0 ₂ or a gas containing C0 ₂ in an amount of from 1 to 50 mol, in particular 2 to 10 moles of CO ₂ per 1 mol of CO. The cobalt salt is then separated from the hydroformylation product in a conventional manner, for example by filtration, decantation or evaporation.

The cobalti carbonyl is decomposed with carbon dioxide under the conditions of the invention. In doing so, the cobalt is converted in one of the carbonate forms or, when the process is carried out in the presence of a mineral or organic acid, the cobalt salt of the corresponding acid:

co ₂

CO ₂ (CO) g -r 2 COCO ₃ + 8 CO co ₂ (co) _e t _C0 ( _HC00 ) + e co + h, o RCOOH *

The reaction takes place in contrast to the known methods without obvyklýoh oxidačníoh means (oxygen vzduohu H ₂ 0 ₂₎ and at temperatures nízkýoh. Carbon dioxide is an oxidizing agent whose oxidation properties are not as strong as those of oxygen, but are sufficient to remove CO ₂ (CO) g from the reaction products of the hydroformylation olefins. The conditions for the action of CO ₂ on cobalt caxbonyls assume a significant excess of CO ₂ (compared to O ₂ ), as well as other, yet acceptable industrial contact times for the reacoe participants. These conditions are compensated by the absence of reactions in which the corresponding acid aldehydes are formed.

The use of pure carbon dioxide or carbon dioxide in the form of gases containing it to decompose cobalt carbonyl has proven unexpected, since oxganic acids used according to literature data to decompose cobalt carboniles have a higher dissociation constant (ooa 10 "^ to 10" ^), while the dissociation constant of carbonic acid is 4.3. 10 “?, Ie by 2 size series. lower and react with the cobalt carbonyl at a temperature of 80 to 160 ° C, carbon dioxide, under the same conditions, also reacts at a lower temperature.

The process according to the invention leads to a simplification of the hydroformylation of olefins, since it is possible to use the waste gases from the decobalting stage which contain CO, EL, CO ₂ and olefin, especially in the case of the use of gaseous olefins, directly in the hydroformylation stage without purification and recovery. When oxidaoi carbonyls ko5 Baltic vzduohem waste gases containing CO, Hg, C0 _2, 0 _2, N _2, and olefins such as propylene or ethylene, either incinerated or after purification regenerated from 0 ₂ and N _2, because 0 ₂ cancels hydroformylaol and Ng represent an easy ballast.

Reduction of environmental conditions reduces the corrosion resistance requirements of the reaction apparatus and improves the thiologologic properties and distillation parameters, end products and by-products of hydroformylation of olefins, since the fraction of acids formed from aldehydes is either converted to esters (with finite alkanols present) or forms hardly separable azeotropes .

The process of the invention is applicable to any hydroformylation process of olefin hydroformylation processes in which cobylic carbonyls such as acr11 are separated, but it is particularly preferred to use it instead of oxidative decobaltation in higher olefin hydroformylation processes (molecular weight over 60) as well as 1 branched chain olefins. polyfunctional unsaturated compounds, since the use of lower temperatures and higher concentrations of cobalt catalysts ensures high hydroformylation speeds and the necessary quality composition of the catalysts in this process. Oxidative decobaltation of high molecular weight catalytic hydroformylation products of olefins or products with increased cobalt catalyst concentration using O ₂ increases the acid formation from 0.5 to 1% to 5 to 104, based on the theoretically calculated amount of the final aldehyde.

Similarly to cobalt carbonyl, it is possible to convert CO ₂ solutions into cobalt salts with no oxygen-containing compounds.

In order to better understand the method of the invention, the following specific examples are set forth.

Example 1

The ethylene hydroformylation product contains 65.0 g of proplonaldehyde, 30 g of organic solvent, 7 g of hydroformylation by-products, and 0.15 g of cobalt carbonyl (Co) based on a three-necked glass slurry equipped with a moulder, backwash and natural gas equipment. products, 0.6 L of carbon dioxide (10 mol of COg per mole of Cl) at 40 ° C, for 90 minutes. The treated product is filtered off from cobalt salts which are returned to the hydroformylation process. The cobalt-dehydrated ethylene hydroformylation product contains 64.8 g of propionaldehyde and not more than 0.0015 wt. 4 Co, is added for further treatment, for example * to the hydrogenol. Aldehyde losses do not exceed 0.3 4.

Example 2

Product hydroformylaoe propylene comprising in 45 g aldehyde máeelné butanol and 55 g of solvent and organlokáho vedlejšíoh hydroformylaoe product and 0.20 g of Co ₂ (CO) g (calculated as Co) was processed to give 0.3 1 of carbon dioxide (3, 7 mol of CO ₂ per 1 mol of CO ₂ at 90 ° C over 25 minutes. The apparatus is analoglocal to Example 1. The cobalt compounds are filtered off, and the product of 212174 6-propylene isoforms contains 44.8 g of butyric acid aldehyde and butyl alcohol and no more than 0.002 wt. % CO is distilled to separate the aldehyde. Aldehyde losses do not exceed 0.2%.

Example 3

The amount and composition of the propylene hydroformylation product are as in Example 2.

The propylene hydroformylation product is treated in a pressure vessel at 20 psi with a gas mixture of 20% air and 80% CC ₂ (1.3 mol CO ₂ per 1 mol Co). The content of cobalt compounds in the hydroformylation product does not exceed 0.002% by weight.

% Co and the aldehyde loss is not more than 0.4

Example 4

The butylene hydroformylation product, which contains 60 g of valeric aldehyde, 40 g of solvent and by-products, 1.5 g of naphthenic acids, 0.12 g of cobalt carbonyl (calculated as Co), is stirred in a pressure vessel at 70 ° It treated 0.8 liters of carbon dioxide (16.7 moles of COg per mole of Co) for 30 minutes. The desired aldehydes and solvent are distilled off from the cobalt-free butylene-free butylene hydroformylation product. The residue, which contains 0.12 g of the highly soluble cobalt salts, is passed to the hydroformylation step and the separated aldehydes of 59.7 g are treated.

The distillation product contains no cobalt compounds. The aldehyde loss does not exceed 0.5 Example 5

Catalytic n-decene catalytic hydroformylation product containing 50 g undecylaldehydes, 45 g of fatty and unsaturated hydrocarbons, by-products and 0.13 g of cobalt carbonyl (calculated as Co) is treated with 0.4 l of carbon dioxide (7.85 mol COg per 1 mol of CO 2 at 60 ° C and at a pressure of 0.2 MPa and the precipitated cobalt salts are filtered off. The hydroformylation product containing no cobalt carbonyl (Co content 0.001 wt%) is hydrogenated in the presence of catalysts. The catalytic hydrogen product contains 49 g undecylalkanols. The loss of the final product with respect to hydrogenation is not more than 2 ° k.

Example 6

The n-tridecene hydroformylation product containing 86 g of tetradeoylaldehyde, 13 g of by-products and unreacted aldehyde and 0.15 g of cobalt carbonyl (calculated as Co) is treated with 1 liter of CO ₂ at 40 ° C for 90 minutes. The instrumentation is as in Example 1. The degree of decomposition of the cobalt carbonyl is over 99 # (cobalt content in the product below 0.0008 wt%). The loss of aldehyde in the decobaltization stages is not more than 1

Example 7

Catalytic acrylonitrile catalytic hydroformylation product containing 30 g of beta cyanopropanal, 67 g of toluene, 2 g of by-products and 0.12 g of cobalt ₇ 213974 (calculated as Co) is treated at 50 ° C for 10 minutes with a gas mixture consisting of 10 $ ₂ 0, 40% and 50 Ng # COG (COG 25 mol per 1 mol of Co). The decayed cobalt compounds (0.115 g Co) are decanted and filtered off. Aldehyde free of cobalt compounds and containing 0,005% by weight % Co, distilled off and hydrogenated. The loss of the aldehyde at the decobaltation stages is not over 2 #.

Example 8

The butylene hydroformylation product containing 60 g of valeric acid aldehyde, 40 g of solvent and by-products of the reaction, 1.5 g of naphthenic acids and 0.12 g of cobalt carbonyl (calculated as Co) is treated with 2.4 at 20 ° C. liters of COg (50 moles of COg per mole of Co). The apparatus is as in Example 4. The degree of decomposition of the cobalt carbonyl is over 99%. The hydroformylation product, which contains 60 g of valeric aldehyde and contains no cobalt, is distilled after distillation. The residue containing 0.12 g of cobalt naphthenate (calculated as Co) was returned to the hydroformylation process. No aldehyde loss was detected.

Example 9

Catalytic hydroformylation product of n-deoene, containing 50 g of undeoylaldehyde, 45 g of hydrocarbons and by-products, as well as 0.13 g of cobalt carbonyl (calculated as Co), is treated at 140 DEG C. under 0.4 MPa for 5 minutes. 2 mol COg per 1 mol Co. The apparatus is as in Example 5. The degree of decomposition of the cobalt carbonyl is 100%. Aldehyde loss is not more than 1%.

EXAMPLE 10 The product hydroformylaoe propylene which contains 45 g of butyraldehyde and butanol, 55 g of solvent and vedlejšíoh hydroformylation product by the reaction, and 0.20 grams Cog (CO) G (gf _{after tžno} j _{as Co) at a} pressure of _0, 3, MPa, at a temperature of 90 ° C, is treated with a gas mixture of 30% argon and 70 µg COg (1 mol COg per 1 mol Co). The apparatus is as in Example 2. The degree of decomposition of the cobalt carbonyl is over 99 #. The cobalt compounds are filtered off and the propylene hydroformylation product contains 44.8 g of butyraldehyde and butyl alcohols and not more than 0.002 wt. % Co, distilled to separate the aldehydes. The losses of aldehydes and alkanols are not over 0.45

Example 11

A 300 g solution of cobalt in pentadiene containing 0.1 g of Co was treated in a pressure vessel with COg (2 moles of COg per mole of Co) at a temperature of 220 ° C and a pressure of 0.2 MPa. After filtering off the insoluble cobalt compounds, it does not contain more than 0.001 g Co.

Claims (2)

1. A process for decobaltizing hydroformylated products of unsaturated compounds by decomposing the catalyst with gas and subsequently removing cobalt salts, characterized in that carbon dioxide or gas is used as the gas. No. 213974 8 containing carbon dioxide, in an amount of 1 to 50 moles of COg per 1 mol of cobalt and decobalt, is carried out at temperatures of 20 to 220 ° C at a pressure of from 1 to 0.4 MPa. 2. The process according to claim 1, wherein the decobaltification is carried out at a temperature of 40 to 140 [deg.] C.