KR100434589B1 - Hydroformylation method of a catalyst for a hydroformylation reaction, a catalyst comprising the same, and a mixed olefin using the same - Google Patents

Abstract

The present invention provides a novel ligand, tetrakis- (2,4-di-tert-butylphenyl) -4,4'-biphenylphosphonite, which is used in the hydroformylation reaction catalyst of mixed olefins, the ligand and rhodium It relates to a catalyst for hydroformylation reaction comprising a, and a method for producing an aldehyde having one more carbon by hydroformylating a mixed olefin obtained by low polymerization of a lower olefin using the catalyst.

Since the catalyst using the ligand of the present invention has excellent activity and selectivity as well as high recovery efficiency after using the catalyst, the recycling efficiency is very high, and thus, the hydroformylation reaction can be efficiently and economically performed when the catalyst of the present invention is used. .

Description

Ligand of the catalyst for hydroformylation reaction, catalyst comprising the same and hydroformylation method of mixed olefin using the same

The present invention provides a new ligand for the hydroformylation reaction catalyst of mixed olefins, a catalyst for hydroformylation reaction comprising the ligand and rhodium, and a mixed olefin obtained by low polymerizing a lower olefin using the catalyst. Formylation relates to a process for producing one more carbon aldehyde.

Low polymerization of lower olefins, such as ethylene, propylene, butene, can produce olefins in a mixture of various isomers such as straight chain terminal olefins, branched terminal olefins, straight chain internal olefins, and branched internal olefins. Hydroformylation reaction of the mixed olefins with the synthesis gas can produce aldehydes having one more carbon atoms, and can be further hydrogenated to prepare alcohols.

Many hydroformylation methods are known for producing aldehydes by reacting olefins with hydrogen and carbon monoxide in the presence of a catalyst. As a catalyst, a complex compound composed of a Group 8 transition metal, in particular rhodium and a ligand, is known, and it is known that the influence of the ligand on the catalytic reaction is great. Depending on the choice of ligand, the hydroformylation reaction activity and selectivity will vary greatly.

In hydroformylation processes in which olefins are reacted with hydrogen and carbon monoxide in the presence of a rhodium catalyst to produce aldehydes, the efficiency of catalyst recovery and recycling is a key condition in determining the economics of the process. Distillation is generally carried out to separate the rhodium catalyst from hydroformylation reaction products containing unreacted olefins, aldehydes, alcohols and rhodium catalysts. When the rhodium catalyst is separated by distillation, the catalyst is volatilized into the distillation product to cause the loss of the catalyst. Therefore, the amount of the lost catalyst should be minimized. Therefore, not only the activity and selectivity of the catalyst but also the stability of the catalyst are very important variables, and the development of effective ligands to improve these properties is an important research field of this technology.

In the hydroformylation process in which olefins are reacted with hydrogen and carbon monoxide in the presence of a rhodium catalyst to produce aldehydes, phosphorus compounds are frequently used as ligands. Among them, phosphine-based compounds are used first. The rhodium catalyst using phosphine as a ligand has high activity and good catalyst stability in hydroformylation of terminal olefins such as propylene, but very low hydroformylation activity for internal olefins. Therefore, it cannot be employed in the hydroformylation reaction for a mixture of olefins in which various isomers such as linear terminal olefins, branched terminal olefins, linear internal olefins and branched internal olefins are mixed.

As a rhodium-based catalyst using another phosphorus ligand, a catalyst employing a phosphite system is known. For example, Japanese Patent Laid-Open Nos. 57-123234 and 5,306,839 disclose tris (2-tert-butylphenyl) phosphite or tris (3,6-di-tert-butyl-2-naphthyl) Triorgano phosphites such as phosphite were used as ligands. International Patent Publication No. WO85 / 03702 discloses diorganophosphites such as 1,1'-biphenyl-2,2'-diyl- (2,6-di-tert-butyl-4-methylphenyl) phosphite as ligands. Used. European Patent Publication No. 518241 A2 uses bisphosphite compounds as ligands, and European Patent No. 697391 A1 uses diorganophosphites, bisphosphites, triorganophosphites, and polyphosphites as ligands. It was.

Although various kinds of phosphorus compounds mentioned above have been proposed as ligands, they are still not satisfactory in the stability of catalysts, and there are still problems in applying them to commercial processes that require long-term activity and stability of catalysts. .

Accordingly, the present invention seeks to provide a new ligand capable of imparting excellent activity, selectivity and stability to the rhodium catalyst for hydroformylation reaction, and is also mixed using the catalyst containing the new ligand and rhodium and the same catalyst. It is to provide a method of hydroformylation reaction of an olefin.

To this end, according to the present invention, tetrakis- (2,4-di-tert-butylphenyl) -4,4'-biphenylphosphonite is provided as a ligand of the rhodium catalyst for hydroformylation reaction.

According to the present invention, there is also provided a catalyst for hydroformylation reaction comprising rhodium and tetrakis- (2,4-di-tert-butylphenyl) -4,4'-biphenylphosphonite ligand. do.

Furthermore, the present invention provides a method for producing aldehyde having more carbon by hydroformylation of a mixed olefin obtained by low polymerization of a lower olefin using the catalyst.

Hereinafter, the present invention will be described in detail.

Tetrakis- (2,4-di-tert-butylphenyl) -4,4'-biphenylphosphonite, which is a rhodium catalyst ligand of the present invention, has been conventionally used for the purpose of antioxidant as a synthetic resin additive, but the present inventors When used as a ligand of the rhodium catalyst for the hydroformylation reaction of mixed olefins, it was first confirmed that the catalyst can be stably maintained while maintaining excellent activity and selectivity of the catalyst. Therefore, the catalyst using the ligand of the present invention has the advantage of having excellent activity and selectivity, as well as a high recovery efficiency after the use of the catalyst, and a very high recycling efficiency.

The catalyst for hydroformylation reaction using the ligand of the present invention comprises a rhodium catalyst and tetrakis- (2,4-di-tert-butylphenyl) -4,4'-biphenylphosphonite. The catalyst of the present invention is a tetrakis- rhodium precursor Rh ₂ (O ₂ CCH ₃ ) ₄ , Rh (CO) ₂ (C ₅ H ₇ O ₂ ), Rh ₆ (CO) ₁₆ or Rh ₄ (CO) ₁₂ and the like. It can be obtained by adding (2,4-di-tert-butylphenyl) -4,4'-biphenylphosphonite. The ligand tetrakis- (2,4-di-tert-butylphenyl) -4,4'-biphenylphosphonite is about 1 to 100 times in molar ratio relative to rhodium metal, preferably 5 to 50 times. It is suitable to use it to double the range. The catalyst according to the present invention is preferably used immediately in the reaction solution.

The catalyst of the present invention can be usefully used in a reaction for producing aldehyde having more carbon by hydroformylation of a mixed olefin obtained by low polymerization of a lower olefin. The amount of the catalyst is not particularly limited but is selected according to the activity or economic aspect of the catalyst. Generally about 1-2000 ppm is used as a rhodium metal with respect to the mixed olefin put into reaction, Preferably 5-200 ppm is suitable.

The hydroformylation process of mixed olefins using the catalyst of the present invention is similar to conventional hydroformylation processes.

As the mixed olefin, C ₆ to C obtained by low-polymerizing ethylene, propylene and butenes under conditions of a reaction pressure of 1 to 100 atm and a reaction temperature of 40 to 100 ° C. using a catalyst carrying nickel, chromium, vanadium, phosphorus, and the like ₁₂ olefins can be used.

Although the use of the reaction solvent is not essential, a solvent that does not participate in the reaction can be used. Suitable solvents include aromatic compounds, ketones, ethers, esters, alcohols and the like.

As raw materials, hydrogen and carbon monoxide are supplied in amounts that participate in the reaction so that the reaction pressure is kept constant. The molar ratio of hydrogen and carbon monoxide is generally from 10: 1 to 1:10, preferably in the range from 2: 1 to 1: 2.

The reaction temperature is preferably in the range of 50 ° C to 200 ° C, preferably in the range of 100 ° C to 170 ° C, and the reaction pressure is suitably in the range from normal pressure to 300 atmospheres, preferably in the range of 50 atmospheres to 200 atmospheres.

Since the tetrakis- (2,4-di-tert-butylphenyl) -4,4'-biphenylphosphonite used as the catalyst ligand in the present invention remains stable even after the hydroformylation reaction of the mixed olefins, After separating the catalyst and the reaction product including the ligand of the present invention by a known method, all or part of the catalyst may be added to the hydroformylation reactor for reuse.

The catalyst of the present invention has high selectivity to obtain a desired product in high yield, excellent stability and very high recovery and recycling efficiency.

Hereinafter, the present invention will be described by way of examples and comparative examples. The following examples are merely provided to facilitate understanding of the present invention, and the present invention is not limited to these examples.

Example

(1) Preparation of Mixed Olefin

Removing the C ₄ butadiene and isobutene from the oil obtained in the naphtha cracking plant and the remaining C ₄ residue of the reaction in the nickel catalyst 10ml continuous fixed bed reactor packed with the supported on alumina pressure of 50 atm, the reaction temperature 70 ℃, space velocity 1.0 The dimerization reaction was carried out under the reaction conditions of hr ⁻¹ . The reaction product was separated by distillation into unreacted C ₄ fractions, dimers, trimers and the like, and a mixed octene which was a mixture of C ₄ fractions dimers was obtained. This mixed octene contains more than 20 kinds of isomers. The mixture is hydrogenated with a palladium catalyst supported on activated carbon, converted to octane, a saturated hydrocarbon, and analyzed by gas chromatography. 68.3 weight%, normal octenes 20,7 weight%.

(2) Hydroformylation Reaction of Mixed Octene

The reactor used a 300 ml high pressure reactor capable of using up to 200 atmospheres. The mixed gas of hydrogen / carbon monoxide mixed 1: 1 was compressed and stored in a 1 L tank capable of using up to 400 atm using a gas compressor, and the reaction pressure was kept constant using a high pressure pressure regulator. The reaction experiment was prepared by compressing the hydrogen / carbon monoxide mixed gas to 300 atm in a pressure vessel by operating a gas compressor.

200 mg of Rh ₂ (O ₂ CCH ₃ ) ₄ was dissolved in 100 ml of methyl alcohol to prepare a rhodium catalyst solution. In a nitrogen glove box, 100 ml of mixed octene prepared by the method of step (1) was added to the reactor, and then a rhodium catalyst solution was added to the reactor so as to be 13.8 ppm relative to mixed octene. As a ligand, 0.18 g of tetrakis- (2,4-di-tert-butylphenyl) -4,4'-biphenylphosphonite was introduced into the reactor, the reactor was sealed, and then attached to the reactor.

The hydrogen / carbon monoxide mixed gas was charged to the reactor up to 30 atmospheres and then purged. After repeating this process three times, hydrogen / carbon monoxide was added to the reactor to maintain the reaction pressure up to 160 atm and the temperature was raised to 140 ℃ to start the reaction. At this time, the rotation speed of the stirrer was 330rpm. During the reaction, the mixed gas was introduced into the reactor by the amount consumed so that the pressure of the reactor was maintained at 160 atm. After 2 hours had elapsed after the start of the reaction, the stirring was stopped and the temperature was lowered to room temperature. After discharging the mixed gas, the product was recovered, and the product was analyzed using a gas chromatograph (Capillary column: HP-5), and conversion, selectivity, and yield were calculated by the following equation, and the results are shown in Table 1.

% Conversion = (weight of olefins consumed / weight of olefins fed) x 100

% Selectivity = (weight of C ₉ product) × 100

Yield (%) = (conversion rate × selectivity) / 100

(3) Isolation of Hydroformylation Reaction Products

The hydroformylation product obtained in step (2) was decompressed to 10 mmHg in a nitrogen atmosphere and distilled at 37 ° C to remove unreacted mixed octene. The remaining mixture of aldehydes, alcohols, high boiling by-products and catalyst was again distilled off under a nitrogen atmosphere at a pressure of 2-3 mmHg at a temperature of 120 ° C. to separate the aldehydes and alcohols with catalyst residues and high boiling by-products. The content of rhodium contained in distillate aldehyde and alcohol was analyzed by an inductive pair plasma-mass spectrometer to determine the amount of catalyst lost. The results are shown in Table 1 below.

(4) Hydroformylation Reaction of Mixed Octene Using Recovered Catalyst

In a glove box in a nitrogen atmosphere, 100 ml of mixed octene prepared by the method of step (1) was added to the reactor, and the catalyst recovered in the distillation residue in step (3) was introduced into the reactor. The hydrogen / carbon dioxide mixed gas was charged to 30 atmospheres and then purged. After repeating this process three times, hydrogen / carbon monoxide was added to maintain the reaction pressure to the desired 160 atm and the temperature was raised to the desired temperature to start the reaction. During the reaction, the mixed gas was introduced into the reactor by the amount consumed to maintain the reactor pressure at 160 atm. After 2 hours after the start of the reaction, the reaction was stopped, the temperature was lowered to room temperature, the mixed gas was discharged, the product was recovered, and the product was analyzed using a gas chromatograph (Capillary column: HP-5). The results are shown in Table 1.

Distillation and analysis were carried out in the same manner as in step (3), and the experiment of reusing with the recovered catalyst was repeated one more time, and the results are shown in Table 1.

Comparative Example 1

It is known that a phosphite compound is effective in improving stability of a rhodium catalyst among phosphorus compounds. In the case of using the phosphite compound as a ligand, an experiment was conducted to investigate the effect of improving the stability of the rhodium catalyst used in the hydroformylation reaction of mixed octene. Steps (1)-(4) of Example 1 except that tris (2,4-di-tert-butylphenyl) phosphite was used as the ligand in the hydroformylation reaction of the mixed octene of step (2) In the same manner as in the preparation of the mixed olefins, hydroformylation reaction, hydroformylation reaction experiments using the catalyst separated and recovered the hydroformylation reaction product was carried out. The results are shown in Table 2.

Comparative Example 2

In the hydroformylation reaction of olefins, phosphine compounds are frequently used as ligands of rhodium catalysts. When using a phosphine compound as a ligand, the experiment was carried out to investigate the effect on the reaction activity and the stability of the rhodium catalyst in the hydroformylation reaction of mixed octene. Preparation of mixed olefins in the same manner as in step (1)-(3) of Example 1, except that triphenylphosphine was used as a ligand in the hydroformylation reaction of the mixed octene of step (2), hydroformyl Separation experiments of the reaction reaction and hydroformylation reaction products were performed and the results are shown in Table 3.

In the above results, in the case of Comparative Example 1 using the tris (2,4-di-tert-butylphenyl) phosphite compound which is a conventional phosphite ligand, the conversion of mixed octene was excellent in the selectivity of C ₉ . Although visible, the stability of the catalyst is poor, and the catalyst residue has already lost 0.115 ppm in two reuses, which presents a problem in terms of catalyst reuse efficiency and economy. In the case of Comparative Example 2 using a triphenylphosphine compound, which is a conventional phosphine ligand, the conversion rate of mixed octene is very low, making industrial use difficult.

On the other hand, when tetrakis- (2,4-di-tert-butylphenyl) -4,4'-biphenylphosphonite according to the present invention is used as a ligand, conventional phosphite in terms of catalyst activity and selectivity The performance was similar to that of the system ligand, and the loss of catalyst residue was maintained at a low level of 0.05 ppm or less, indicating that the catalyst reuse efficiency and economy were very good.

The ligand according to the present invention and the rhodium catalyst including the same can be used industrially since they show excellent properties in the preparation of aldehyde having more carbon by hydroformylation of a mixed olefin obtained by low polymerization of lower olefins. have.

Claims (6)

Tetrakis- (2,4-di-tert-butylphenyl) -4,4'-biphenylphosphonite used as ligand of a rhodium catalyst for hydroformylation reaction. A catalyst for hydroformylation reaction comprising rhodium and tetrakis- (2,4-di-tert-butylphenyl) -4,4'-biphenylphosphonite ligand. The catalyst for hydroformylation reaction according to claim 2, wherein the molar ratio of the ligand to the rhodium is 5 to 50 times. In a method in which a mixed olefin obtained by low polymerization of a lower olefin is reacted with hydrogen and carbon monoxide to convert an aldehyde having more carbon atoms, rhodium and tetrakis- (2,4-di-tert-butylphenyl) -4 as catalysts And a catalyst comprising a 4'-biphenylphosphonite ligand. The method of claim 4, wherein Characterized in that the said mixed olefin C ₂ ~ C ₄ olefins of C ₆ ~ C ₁₂ olefins obtained by combining low-middle. The method of claim 4, wherein Wherein said catalyst is used in an amount of 5 ppm to 200 ppm with rhodium metal relative to mixed olefins.