KR20220055848A - Manufacturing method of aldehyde - Google Patents

Abstract

The present invention relates to a method for preparing an aldehyde, including the steps of: allowing an olefin-based compound to react with syngas in the presence of a catalyst for hydroformylation in a hydroformylation reactor to form a reaction product containing an aldehyde; introducing the reaction product containing an aldehyde to a distillation device; separating a low-boiling point ingredient of the reaction product at the top of the distillation device, while separating a high-boiling point ingredient of the reaction product at the bottom of the distillation device; and recycling at least a part of the low-boiling point ingredient separated at the top of the distillation device to the distillation device in the form of spray.

Description

Aldehyde production method {MANUFACTURING METHOD OF ALDEHYDE}

The present application relates to a method for producing an aldehyde.

In the presence of a homogeneous organometallic catalyst and ligand, various olefins are reacted with carbon monoxide (CO) and hydrogen (H ₂ ), which are often called synthesis gases, to increase the number of carbons by one (linear, normal) and branched (iso) ) The hydroformylation reaction to produce aldehydes was first discovered in 1938 by Otto Roelen of Germany.

In general, the hydroformylation reaction known as the oxo (OXO) reaction is an industrially very important reaction in a homogeneous catalytic reaction, and various aldehydes including alcohol derivatives are produced and consumed worldwide through the oxo process.

Various aldehydes synthesized by the oxo reaction are oxidized or hydrogenated after a condensation reaction such as aldol, and are sometimes transformed into various acids and alcohols containing a long alkyl group. In particular, the hydrogenated alcohol of aldehyde by the oxo reaction is called oxo alcohol, and oxo alcohol is widely used industrially, such as solvents, additives, raw materials for various plasticizers, and synthetic lubricants.

Currently, the catalysts used in the oxo process are mainly cobalt (Co) and rhodium (Rh) series, and the ratio of linear (normal) to branched (ratio of linear (normal) to branched (ratio of linear (normal) to branched ( iso) isomers) are different. Currently, more than 70% of oxo plants around the world are adopting the Low Pressure OXO Process using a rhodium-based catalyst.

In addition to cobalt (Co) and rhodium (Rh) as the central metal of the oxo catalyst, iridium (Ir), ruthenium (Ru), osmium (Os), platinum (Pt), palladium (Pd), iron (Fe), nickel (Ni) ) can be applied. However, since it is known that each metal exhibits catalytic activity in the order of Rh >> Co > Ir, Ru > Os > Pt > Pd > Fe > Ni, most of the processes and research are focused on rhodium and cobalt.

Ligands include phosphine (Phosphine, PR ₃ , R is C ₆ H ₅ , or nC ₄ H ₉ ), phosphine oxide (Phosphine Oxide, O=P(C ₆ H ₅ ) ₃ ), phosphite, Amine (Amine), amide (Amide), isonitrile (Isonitrile) and the like are applicable.

A typical example of hydroformylation is to prepare octanol (2-ethylhexanol) from propylene using a rhodium-based catalyst.

Octanol is mainly used as a raw material for PVC plasticizers such as DOP (Dioctyl Phathalate), and is also used as an intermediate raw material for synthetic lubricants and surfactants. Propylene is fed into the oxo reactor using a catalyst together with synthesis gas (CO/H ₂ ) to produce n-butylaldehyde and iso-butylaldehyde. The resulting aldehyde mixture is sent to a separation system together with the catalyst mixture to be separated into hydrocarbon and catalyst mixture, the catalyst mixture is circulated to the reactor, and the hydrocarbon component is transferred to a stripper. The hydrocarbons in the stripper are stripped by the freshly supplied synthesis gas, unreacted propylene and synthesis gas are recovered to the oxo reactor, and butyraldehyde is transferred to a fractionation column and separated into n- and iso-butylaldehyde, respectively. Normal-butylaldehyde at the bottom of the fractionation column is introduced into the aldol condensation reactor to produce 2-ethylhexanal by condensation and dehydration reaction, and then transferred to the hydrogenation reactor, and octanol (2-ethylhexanol) is produced by hydrogenation. do. The reactants at the outlet of the hydrogenation reactor are transferred to a fractionation column, and the soft/hard ends are separated to produce an octanol product.

The hydroformylation reaction can be carried out continuously, semi-continuously or batchwise, typical hydroformylation reaction processes are gas or liquid recycle systems. In the hydroformylation reaction, it is important to increase the reaction efficiency by allowing the starting materials in liquid phase and gas phase to contact smoothly. For this purpose, conventionally, a continuous stirred tank reactor (CSTR) in which liquid and gaseous components are stirred to uniformly contact in the reactor has been mainly used.

In this regard, in the prior art, since the value of the normal-aldehyde among the aldehydes produced by the oxo reaction was high, most of the studies on catalysts have been conducted in the direction of increasing the ratio of the linear aldehyde derivative, but recently Branched aldehyde derivatives (iso-aldehyde) as raw materials, for example, isobutyric acid, neopentyl glycol (NPG), 2,2,4-trimethyl-1,3-pentanediol (2,2) ,4-trimethyl-1,3-pentanediol), isovaleric acid, etc. As the demand for isoaldehyde increases due to the development of it, research in the direction of increasing the selectivity of the branched aldehyde derivative is continuing. .

US Patent Publication No. 4,215,077

The present application intends to provide a method for preparing an aldehyde.

An exemplary embodiment of the present application is,

forming a reaction product including an aldehyde by reacting an olefin-based compound with a synthesis gas in a hydroformylation reactor under a catalyst for hydroformylation reaction;

introducing the reaction product containing the aldehyde into a distillation apparatus;

separating the low-boiling-point components of the reaction product through the upper portion of the distillation apparatus and separating the high-boiling-point components of the reaction product through the lower portion of the distillation apparatus; and

Recirculating at least a portion of the low boiling point components separated to the upper part of the distillation apparatus in the form of a spray to the distillation apparatus,

Based on the flow rate of the low boiling point component separated into the upper part of the distillation device, the flow rate of the low boiling point component recycled to the distillation device is 0.05 wt% to 1.0 wt%.

The method for producing an aldehyde according to an exemplary embodiment of the present application includes recirculating at least a portion of the low boiling point components separated to the upper part of the distillation apparatus in a spray form to the distillation apparatus. Accordingly, by minimizing the amount of the catalyst for the hydroformylation reaction entrained with the aldehyde to the upper part of the distillation apparatus, the amount of the catalyst that needs to be additionally added for the hydroformylation reactivity can be minimized.

1 is a diagram schematically showing a manufacturing process of an aldehyde according to an exemplary embodiment of the present application.
2 is a diagram schematically showing a conventional manufacturing process of an aldehyde.

Hereinafter, the present application will be described in more detail.

In this specification, when a member is said to be located "on" another member, this includes not only a case in which a member is in contact with another member but also a case in which another member exists between the two members.

In the present specification, when a part "includes" a certain component, this means that other components may be further included, rather than excluding other components, unless otherwise stated.

In the oxo (OXO) process, in the process in which the catalyst and the aldehyde product are separated in the distillation apparatus after the hydroformylation step, a phenomenon in which a part of the catalyst is entrained with the aldehyde product occurs. Accordingly, after a certain period of time, there may be a problem in that a catalyst needs to be additionally added to the hydroformylation reactor for hydroformylation reactivity, and a process of separating the catalyst from the aldehyde product may be added.

In order to solve the above problems, in the present application, in the process in which the catalyst and the aldehyde product are separated in the distillation apparatus after the hydroformylation reaction step, a phenomenon in which a part of the catalyst is entrained with the aldehyde product was minimized.

The method for producing an aldehyde according to an exemplary embodiment of the present application includes the steps of: reacting an olefin-based compound with a synthesis gas in a hydroformylation reactor under a catalyst for hydroformylation reaction to form a reaction product containing an aldehyde; introducing the reaction product containing the aldehyde into a distillation apparatus; separating the low-boiling-point components of the reaction product through the upper portion of the distillation apparatus and separating the high-boiling-point components of the reaction product through the lower portion of the distillation apparatus; and recycling at least a portion of the low boiling point components separated to the upper part of the distillation apparatus to the distillation apparatus in the form of a spray, and recirculating to the distillation apparatus based on the flow rate of the low boiling point components separated to the upper part of the distillation apparatus The flow rate of the low boiling point component to be used is 0.05 wt% to 1.0 wt%.

In an exemplary embodiment of the present application, the low-boiling component separated into the upper part of the distillation apparatus may include an aldehyde, an unreacted olefin-based compound, and a synthesis gas. At this time, at least a portion of the low-boiling component separated to the upper part of the distillation apparatus is recycled to the distillation apparatus in the form of a spray. As described above, by recycling at least a portion of the low boiling point components separated to the upper part of the distillation apparatus to the distillation apparatus in the form of a spray, the catalyst for hydroformylation reaction that can be entrained in the low boiling point components separated into the upper part of the distillation apparatus can be separated from the aldehyde product.

In particular, in the process of recycling at least a portion of the low boiling point components separated to the upper part of the distillation apparatus to the distillation apparatus, when applied in a simple liquid form rather than a spray form, even when the recirculation process is performed. It is difficult or insignificant to separate the catalyst for hydroformylation reaction, which may be entrained in the low boiling point component separated at the top, from the aldehyde product. Therefore, it is not preferable because only energy for maintaining the temperature of the distillation apparatus is further used.

In an exemplary embodiment of the present application, based on the flow rate of the low boiling point component separated into the upper part of the distillation apparatus, the flow rate of the low boiling point component recycled to the distillation apparatus may be 0.05 wt% to 1.0 wt%, and 0.1 wt% to 0.8% by weight. Based on the flow rate of the low boiling point component separated to the upper part of the distillation apparatus, when the flow rate of the low boiling point component recycled to the distillation apparatus is less than 0.05% by weight, hydro that may be entrained in the low boiling point component separated into the upper part of the distillation apparatus The effect of separating the catalyst for the formylation reaction from the aldehyde product may be insignificant. In addition, heavies, which may be produced with the aldehyde product, may also be separated at the top of the distillation unit. Therefore, when the flow rate of the low-boiling-point component recycled to the distillation apparatus exceeds 1.0% by weight, heavy oil is highly likely to accumulate in the reactor, which is not preferable because it may cause a problem of continuously increasing the temperature of the distillation apparatus. .

In an exemplary embodiment of the present application, the high boiling point component separated into the lower part of the distillation apparatus may include an aldehyde and a catalyst for hydroformylation. At this time, the high boiling point component separated into the lower part of the distillation apparatus may be recycled to the hydroformylation reactor.

In an exemplary embodiment of the present application, by recycling at least a portion of the low boiling point component separated to the upper part of the distillation apparatus to the distillation apparatus in the form of a spray, a hydro that can be entrained in the low boiling point component separated into the upper part of the distillation apparatus The catalyst for the formylation reaction can be separated from the aldehyde product. Accordingly, based on the weight of the low boiling point component finally separated to the upper part of the distillation apparatus, the content of the catalyst for the hydroformylation reaction present in the low boiling point component may be 10 ppm or less, 5 ppm or less, and may be 0 .

In an exemplary embodiment of the present application, the temperature in the distillation apparatus may be 50°C to 150°C, and 80°C to 120°C. In addition, the pressure in the distillation apparatus may be 0.1 bar to 3 bar, it may be 0.3 bar to 1 bar. When the temperature range and pressure range of the distillation apparatus are satisfied, the amount of the catalyst for the hydroformylation reaction entrained with the aldehyde to the upper part of the distillation apparatus can be minimized.

In an exemplary embodiment of the present application, the catalyst for the hydroformylation reaction may include a ligand represented by any one of Formulas 1 to 5 and a transition metal compound represented by Formula 6 below.

[Formula 1]

[Formula 2]

[Formula 3]

[Formula 4]

[Formula 5]

[Formula 6]

M(L1)x(L2)y(L3)z

In Formula 6,

M is cobalt (Co), rhodium (Rh), iridium (Ir), ruthenium (Ru), iron (Fe), nickel (Ni), palladium (Pd), platinum (Pt) or osmium (Os),

L1, L2 and L3 are the same as or different from each other, and each independently hydrogen, carbonyl (CO), cyclooctadiene, norbornene, chlorine, triphenylphosphine (TPP) or acetylacetonato (AcAc),

x, y and z are each independently 0 to 5, and x, y and z are not 0 at the same time.

In an exemplary embodiment of the present application, based on 1 mole of the ligand represented by any one of Formulas 1 to 5, the content of the transition metal compound represented by Formula 6 may be 0.003 mole to 0.05 mole, and 0.004 mole to 0.045 mole moles, and may be 0.0042 moles to 0.042 moles. Based on 1 mole of the ligand represented by any one of Formulas 1 to 5, when the content of the transition metal compound represented by Formula 6 satisfies 0.003 mole to 0.05 mole, the activity of the catalyst for the hydroformylation reaction is It may be excellent, and when it is out of the above range, there may be problems in which catalyst activity and stability are deteriorated.

The transition metal compound represented by Formula 6 is cobalt carbonyl (Co ₂ (CO) ₈ ), acetylacetonatodicarbonylrhodium (Rh(AcAc)(CO) ₂ ), acetylacetonatocarbonyltriphenylphosphine Rhodium (Rh(AcAc)(CO)(TPP)), hydridocarbonyltri(triphenylphosphine)rhodium[HRh(CO)(TPP) ₃ ], acetylacetonatodicarbonyliridium (Ir(AcAc)) CO) ₂ ) and hydridocarbonyltri(triphenylphosphine)iridium (HIr(CO)(TPP) ₃ ) may be at least one selected from the group consisting of.

In an exemplary embodiment of the present application, the olefin-based compound may be represented by the following formula (7).

[Formula 7]

In Formula 7,

R ₅ and R ₆ are the same as or different from each other, and each independently hydrogen, an alkyl group, fluorine (F), chlorine (Cl), bromine (Br), trifluoromethyl (-CF ₃ ), or substituted or unsubstituted It is an aryl group.

The aryl group may be unsubstituted or substituted with one or more substituents selected from among nitro (—NO ₂ ), fluorine (F), chlorine (Cl), bromine (Br), methyl, ethyl, propyl, and butyl.

More specifically, the olefin-based compound may be at least one selected from the group consisting of ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, and styrene.

In an exemplary embodiment of the present application, the olefin-based compound may be propylene, and the aldehyde may be butyraldehyde.

In an exemplary embodiment of the present application, the hydroformylation reaction is a mixed solution of the transition metal compound and the ligand by dissolving the transition metal compound represented by Formula 6 and the ligand represented by any one of Formulas 1 to 5 in a solvent, That is, it can be carried out by preparing a catalyst composition, injecting the olefin-based compound represented by Chemical Formula 7 and the synthesis gas together with the catalyst composition into a reactor, and increasing the temperature and pressure while stirring.

The solvent is propane aldehyde, butyl aldehyde, pentyl aldehyde, valer aldehyde, acetone, methyl ethyl ketone, methyl isobutyl ketone, acetophenone, cyclohexanone, ethanol, pentanol, octanol, thesanol, benzene, toluene, xylene, It may be at least one selected from the group consisting of orthodichlorobenzene, tetrahydrofuran, dimethoxyethane, dioxane, methylene chloride and heptane.

In an exemplary embodiment of the present application, the step of reacting the olefin-based compound with the synthesis gas in the hydroformylation reactor may be performed at a temperature of 50° C. to 90° C. and a pressure of 5 bar to 25 bar, and 55° C. to 85° C. It can be carried out at a temperature of ℃ and a pressure of 8 bar to 18 bar. When the temperature of the hydroformylation reaction step is less than 50 °C, the reactivity may be significantly lowered, and if it exceeds 90 °C, the content of the heavies material increases and the yield may decrease. In addition, when the pressure of the hydroformylation reaction step is less than 5 bar, the reactivity may be significantly lowered, and if it exceeds 25 bar, there are disadvantages in terms of cost and design of the device.

In an exemplary embodiment of the present application, in the hydroformylation reaction step, the molar ratio of the olefin-based compound to the synthesis gas may be 95:5 to 5:95, and 75:25 to 25:75. In the hydroformylation reaction step, when the molar ratio of the olefin-based compound: synthesis gas is 95: 5 to 5: 95, the catalyst activity for the hydroformylation reaction may be excellent, and if it is outside the above range, Catalyst activity and stability may be deteriorated.

1 below schematically shows a manufacturing process of an aldehyde according to an exemplary embodiment of the present application, and FIG. 2 below schematically shows a conventional manufacturing process of an aldehyde.

As shown in Figure 1 below, in the method for producing an aldehyde according to an exemplary embodiment of the present application, an olefin-based compound is reacted with a synthesis gas in a hydroformylation reactor under a catalyst for hydroformylation reaction to obtain a reaction product containing an aldehyde forming; introducing the reaction product containing the aldehyde into a distillation apparatus; separating the low-boiling-point components of the reaction product through the upper portion of the distillation apparatus and separating the high-boiling-point components of the reaction product through the lower portion of the distillation apparatus; and recycling at least a portion of the low boiling point components separated to the upper part of the distillation apparatus to the distillation apparatus in the form of a spray, and recirculating to the distillation apparatus based on the flow rate of the low boiling point components separated to the upper part of the distillation apparatus The flow rate of the low boiling point component to be used is 0.05 wt% to 1.0 wt%.

Hereinafter, examples will be given to describe the present application in detail. However, the embodiments according to the present application may be modified in various other forms, and the scope of the present application is not to be construed as being limited to the embodiments described in detail below. The embodiments of the present application are provided to more completely explain the present application to those of ordinary skill in the art.

<Example>

<Examples 1 to 4 and Comparative Examples 1 to 3>

As catalysts, rhodium acetylacetonato carbonyl triphenylphosphine (Rh(AcAc)(CO)(TPP), ROPAC) and tris(2-tert-butyl-4-methylphenyl)phosphine (tris( 2-tert-butyl-4-methylphenyl)phosphite, TTBMPP) was used. In addition, the hydroformylation reaction was performed by introducing a mixed gas containing C ₃ H ₆ , H ₂ and CO into the reactor equipped with the catalyst, and then the reaction product containing butyraldehyde was produced at a flow rate described in Table 1 below. was put into the distillation apparatus.

The distillation apparatus was maintained at 0.5 bar and 90° C., and the top flow rate of the distillation apparatus and the bottom flow rate of the distillation apparatus were adjusted as described in Table 1 below. In addition, as shown in Table 1 below, a portion of the flow rate at the top of the distillation apparatus was recycled to the distillation apparatus in the form of a spray.

<Comparative Example 4>

Instead of recirculating a portion in the form of spray to the distillation apparatus at the top flow rate of the distillation apparatus, as shown in Table 1 below, except for recycling a portion in the form of a simple liquid to the distillation apparatus at the top flow rate of the distillation apparatus, the above It was carried out in the same manner as in Example 1.

[Table 1]

<Experimental Example 1>

In Examples and Comparative Examples, the catalyst in the final product separated into the upper part of the distillation apparatus was analyzed through metal analysis (ICP-OES), and the content of the ligand was analyzed by gas chromatography (GC-FID), and the result was It is shown in Table 2 below.

<GC analysis conditions>

1) Column: HP-1(L:30m, ID:0.32mm, film:1.05m)

2) Injection volume: 1 μl

3) Inlet Temp.: 250℃, Pressure: 6.92psi, Total flow: 64.2ml/min, Split flow: 60ml/min, spilt ratio: 50:1

4) Column flow: 1.2ml/min

5) Oven temp.: 70℃/3min-10℃/min-280℃/35min

6) Detector temp.: 280℃, H ₂ : 35ml/min, Air: 300ml/min, He: 20ml/min

7) GC Model: Agilent 7890

<ICP-OES analysis>

The ICP-OES analysis method is as follows.

1) About 10 g of the sample was accurately measured in a platinum crucible.

2) The solvent component was concentrated by heating on a hot plate.

3) 1 mL of nitric acid was added and heated.

4) The sample was dried by heating.

5) 1mL of concentrated nitric acid was added, and 200 μl of hydrogen peroxide was added (try 2 to 3 times).

6) When the organic matter was dissolved, 1 mL of nitric acid was added and heated.

7) When the sample is clearly dissolved, it was diluted with 10 mL of ultrapure water.

8) ICP-OES (PERKIN-ELMER, OPTIMA 8300DV) was analyzed.

[Table 2]

As described above, in the case of Examples 1 to 4, in which the flow rate of the low boiling point component recycled to the distillation device is 0.05 wt% to 1.0 wt% based on the flow rate of the low boiling point component separated to the upper part of the distillation device, the final No rhodium catalyst was detected in the product and the ligand content was less than 4ppm. However, Comparative Examples 1 and 2 in which the low boiling point component was not recycled to the distillation apparatus, Comparative Example 3 in which the flow rate of the low boiling point component recycled to the distillation apparatus was 0.03% by weight, and Comparative Example in which the low boiling point component was recycled in the form of a simple liquid rather than in the form of a spray In case 4, a rhodium catalyst was detected in the final product, and the ligand content was 15 ppm or more.

In addition, an experiment was attempted when the flow rate of the low boiling point component recycled to the distillation apparatus exceeded 1.0 wt%, but the temperature of the distillation apparatus increased excessively, and the experiment was stopped due to stability problems.

As described above, the method for producing an aldehyde according to an exemplary embodiment of the present application includes recirculating at least a portion of the low boiling point components separated to the upper part of the distillation apparatus in a spray form to the distillation apparatus. Accordingly, by minimizing the amount of the catalyst for the hydroformylation reaction entrained with the aldehyde to the upper part of the distillation apparatus, the amount of the catalyst that needs to be additionally added for the hydroformylation reactivity can be minimized.

Claims (8)

forming a reaction product including an aldehyde by reacting an olefin-based compound with a synthesis gas in a hydroformylation reactor under a catalyst for hydroformylation reaction;
introducing the reaction product containing the aldehyde into a distillation apparatus;
separating the low boiling point components of the reaction product through the upper portion of the distillation apparatus and separating the high boiling point components of the reaction product through the lower portion of the distillation apparatus; and
Recirculating at least a portion of the low boiling point components separated to the upper part of the distillation apparatus in the form of a spray to the distillation apparatus,
Based on the flow rate of the low-boiling-point component separated into the upper part of the distillation apparatus, the flow rate of the low-boiling-point component recycled to the distillation apparatus is 0.05 wt% to 1.0 wt%. The method according to claim 1, wherein the low-boiling component separated into the upper part of the distillation apparatus includes an aldehyde, an unreacted olefin-based compound, and a synthesis gas. The method according to claim 1, wherein the high boiling point component separated into the lower part of the distillation apparatus comprises an aldehyde and a catalyst for hydroformylation reaction. The method according to claim 3, wherein the high-boiling component separated into the lower part of the distillation apparatus is recycled to the hydroformylation reactor. The method according to claim 1, wherein the catalyst for the hydroformylation reaction comprises a ligand represented by any one of Formulas 1 to 5 and a transition metal compound represented by Formula 6 below:
[Formula 1]

[Formula 2]

[Formula 3]

[Formula 4]

[Formula 5]

[Formula 6]
M(L1)x(L2)y(L3)z
In Formula 6,
M is cobalt (Co), rhodium (Rh), iridium (Ir), ruthenium (Ru), iron (Fe), nickel (Ni), palladium (Pd), platinum (Pt) or osmium (Os),
L1, L2 and L3 are the same as or different from each other, and each independently hydrogen, carbonyl (CO), cyclooctadiene, norbornene, chlorine, triphenylphosphine (TPP) or acetylacetonato (AcAc),
x, y and z are each independently 0 to 5, and x, y and z are not 0 at the same time. The method for producing an aldehyde according to claim 1, wherein the olefin-based compound is represented by the following Chemical Formula 7:
[Formula 7]

In Formula 7,
R ₅ and R ₆ are the same as or different from each other, and each independently hydrogen, an alkyl group, fluorine (F), chlorine (Cl), bromine (Br), trifluoromethyl (-CF ₃ ), or substituted or unsubstituted It is an aryl group. The method according to claim 1, wherein the olefin-based compound is at least one selected from the group consisting of ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, and styrene. The method according to claim 1, wherein the olefin-based compound is propylene, and the aldehyde is butyraldehyde.

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