Metal catalyst recovery method and system for homogeneous hydroformylation reaction

Abstract

The invention discloses a metal catalyst recovery method and system for homogeneous hydroformylation reaction liquid, and the method comprises the following steps: obtaining the hydroformylation reaction liquid, and removing light components in the hydroformylation reaction liquid to obtain heavy components; uniformly mixing the heavy component with a first extraction agent, and performing phase splitting to obtain a first heavy component phase and a first extraction agent phase; separating the first extractant phase to obtain a metal catalyst and a second extractant, then uniformly mixing the second extractant with the first heavy component phase, and performing phase splitting to obtain heavy component residual liquid and a second extractant phase; the second extractant phase is used as a first extractant mixed with the heavy component. According to the method, the homogeneous hydroformylation catalyst can be simply, safely and continuously recovered with high yield, the operation condition is mild, the emission of three wastes is less, the recovery cost of the catalyst is reduced, and the conversion rate of industrial hydroformylation continuous reaction is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of hydroformylation reaction, and in particular to a method and system for recovering a metal catalyst used in a homogeneous hydroformylation reaction liquid. Background Art

[0002] Hydroformylation is a classic reaction in the chemical industry for producing aldehydes. It involves the addition of olefins to synthesis gas consisting of hydrogen and carbon monoxide under specific temperature, pressure, and catalyst-assisted conditions to produce carbon-one-added aldehydes, which are important raw materials and intermediates for the preparation of various fine chemicals. Hydroformylation catalysts typically contain metals with high active centers, such as rhodium, cobalt, osmium, and ruthenium. Therefore, in industrial production, it is desirable to recover as much of the metal catalyst as possible to maintain high conversion rates in the hydroformylation reaction in order to reduce reaction costs.

[0003] Catalytic systems for hydroformylation reactions include homogeneous and heterogeneous systems. Homogeneous systems offer advantages such as high catalytic activity, good selectivity, and mild reaction conditions, making them more widely used in industrial hydroformylation reactions. In homogeneous systems, the reaction solvent used to dissolve the metal catalyst is typically a high-boiling-point solvent for heavy components, such as dimerization and trimerization condensates of aldehydes. Therefore, even if light components such as olefins, alkanes, and aliphatic aldehydes can be evaporated from the hydroformylation reaction solution obtained after the hydroformylation reaction, it is difficult to separate the heavy components from the metal catalyst by heating and evaporation. As the reaction time increases, a large amount of heavy components remain in the reaction system, seriously affecting the subsequent recovery of the metal catalyst and also causing a decrease in the conversion rate and aldehyde yield of the hydroformylation reaction.

[0004] In order to recover more metal catalysts in a homogeneous catalytic system and reduce the accumulation of heavy components, patent CN113289695A discloses a method for recovering an olefin hydroformylation catalyst. The method comprises adding an aqueous solution of a strong oxidant, a water-resistant Lewis acid, and a complexing agent to the hydroformylation reaction liquid to extract the catalyst. After phase separation, the aqueous phase is further pre-carbonylated. The pre-carbonylated product is then separated into an organic phase containing the catalyst and an aqueous phase containing the water-resistant Lewis acid and the complexing agent. Finally, the organic phase is returned to the hydroformylation reaction, and the aqueous phase is mixed with a strong oxidant and reused for recovery of the reaction liquid.

[0005] Currently, such metal catalyst recovery methods all require the use of Lewis acids, chelating agents and other substances to extract the metal catalyst from the oil phase to the water phase through chemical reactions to achieve the transfer of the metal catalyst between phases. This method has a series of problems such as long routes and complex operations. At the same time, the recovery rate of the metal catalyst still needs to be further improved, and the accumulation problem of heavy components has not been effectively alleviated. Summary of the Invention

[0006] One object of the present invention is to provide a method for recovering a metal catalyst from a homogeneous hydroformylation reaction liquid. The method utilizes the difference in solubility between heavy components and the metal catalyst in the hydroformylation reaction liquid under specific conditions to first extract the majority of the metal catalyst. The separated weakly polar phase containing the heavy components is then subjected to a second extraction with an extractant. The extractant phase containing a small portion of the metal catalyst obtained from the second extraction is then used again as an extractant to circulate the hydroformylation reaction liquid, thereby significantly improving the recovery rate of the metal catalyst. Simultaneously, the heavy component residue remaining after the second extraction is discharged, thereby significantly reducing the accumulation of heavy components in the hydroformylation cycle reaction.

[0007] The above-mentioned purpose of the present invention is achieved through the following technical solutions:

[0008] A method for recovering a metal catalyst from a homogeneous hydroformylation reaction liquid comprises the following steps:

[0009] obtaining a hydroformylation reaction liquid, removing light components from the hydroformylation reaction liquid, and obtaining a heavy component;

[0010] The heavy component and the first extractant are mixed uniformly, and phase separation is performed to obtain a first heavy component phase and a first extractant phase;

[0011] Separating the metal catalyst and the second extractant from the first extractant phase, then uniformly mixing the second extractant with the first heavy component phase, and performing phase separation to obtain a heavy component residue and a second extractant phase;

[0012] The second extractant phase serves as the first extractant mixed with the heavy components.

[0013] In this technical solution, the hydroformylation reaction liquid obtained after the completion of the hydroformylation reaction contains light components and heavy components, wherein the light components mainly include olefins, alkanes and fatty aldehydes, and the heavy components mainly include metal catalysts and condensation heavy components such as dimerization and trimerization of fatty aldehydes. In some preferred embodiments, the fatty aldehydes in the light components can be C4~C 14 Fatty aldehydes, such as butyraldehyde and tetradecanal, correspondingly, the dimerization and trimerization condensation products in the heavy components are C4~C 14 The condensation heavy components such as dimerization and trimerization of fatty aldehydes can be obtained by evaporation, stripping and other methods to remove light components such as olefins, alkanes and fatty aldehydes in the hydroformylation reaction liquid to obtain heavy components containing metal catalysts.

[0014] In the present technical solution, the metal catalyst is extracted with a first extractant by utilizing the difference in solubility between the metal catalyst and other condensed heavy components in the heavy component under specific conditions. After the extraction is completed, the mixture is allowed to stand, cool, and separate into phases. The upper first heavy component phase is a weakly polar phase containing the residual liquid of the heavy component, while the lower first extractant phase is a polar phase containing most of the metal catalyst. Next, the second extractant is separated from the first extractant phase by evaporation or the like, and the remaining high concentration of metal catalyst, that is, most of the metal catalyst in the heavy component, is separated. In one or more embodiments, the separated second extractant is maintained in the same or similar composition and ratio as the first extractant by adding the extractant. In some embodiments, the second extractant can also be adjusted to a different ratio from the first extractant as the time of the continuous hydroformylation reaction increases.

[0015] Exploiting solubility differences allows for the separation of a significant portion of the catalyst without introducing additional substances to react with the metal catalyst. For example, over 85% of the metal catalyst in the hydroformylation reaction solution can be recovered. However, a small amount of the metal catalyst remains in the first heavy phase, and the residual heavy phase remains trapped in the continuous reaction system.

[0016] To this end, in this technical solution, a second extractant is continued to be used to extract the first heavy component phase. After phase separation, the upper weakly polar phase is the heavy component residual liquid, which can be directly transported to the residual liquid tank for collection and then discharged from the continuous reaction system; the lower second extractant phase contains a small portion of metal catalyst. The second extractant phase does not require additional separation of the metal catalyst and extractant, but is directly recycled to the first extraction kettle, replacing the first extractant to mix with the heavy component. Then, in the subsequent cyclic reaction process, the small portion of metal catalyst contained in it is separated and collected together with the majority of the metal catalyst, resulting in a total recovery rate of the metal catalyst as high as 98.2%, significantly improving the recovery rate of the metal catalyst. At the same time, the discharge of the heavy component residual liquid significantly reduces the accumulation of heavy components in the hydroformylation cycle reaction, effectively improving the conversion rate of the industrial hydroformylation continuous reaction and reducing the reaction cost.

[0017] In one or more embodiments, the metal catalyst is preferably a rhodium catalyst.

[0018] In some embodiments, the first extractant may be at least one of N,N-dimethylformamide (DMF), N,N-diethylformamide, acetonitrile, N-methylpyrrolidone (NMP), and formamide.

[0019] As a preferred embodiment of the first extractant in the present invention, the first extractant is composed of extractant A and extractant B, wherein the extractant A is N,N-dimethylformamide or formamide, and the extractant B is N-methylpyrrolidone.

[0020] In this technical solution, the first extractant is a combination of extractant A and extractant B, wherein extractant A is DMF or formamide, and extractant B is NMP. This combination of two polar compounds effectively exploits the solubility difference between the metal catalyst and the condensate, extracting the majority of the catalyst from the heavy components. In some embodiments, the ratio of extractant A to extractant B can be 100:1 to 1:100.

[0021] Furthermore, the volume ratio of the extractant A to the extractant B is 1.2 to 20. In this technical solution, through continuous hydroformylation reaction, it was found that within a certain period of time of the continuous reaction, the amount of extractant A should be greater than the amount of extractant B. In a preferred embodiment, when the volume ratio of extractant A to extractant B is 1.2 to 20, the total recovery rate of the metal catalyst can be basically maintained at more than 90%. Further preferably, the volume ratio of extractant A to extractant B is 95:5 to 55:45. Even more preferably, extractant A is DMF, extractant B is NMP, and the volume ratio of DMF to NMP is 95:5.

[0022] In some embodiments, within a certain period of time during the continuous reaction, for example, within 500 hours, before the second extractant is mixed with the first heavy component, extractant A and / or extractant B is added to the second extractant to ensure that the second extractant maintains the same composition and ratio as the first extractant.

[0023] Furthermore, as a preferred embodiment of the present invention, after a certain reaction time, extractant A and / or extractant B are added so that the volume ratio of extractant B to extractant A in the second extractant is 1 to 1.1.

[0024] Although most of the heavy component residual liquid in the continuous reaction system can be discharged through two extractions, as the continuous reaction time increases, the heavy components in the continuous reaction system and the amount of high polymers in the heavy components will also increase to a certain extent, resulting in an increase in the density of the upper heavy component phase. As a result, the separation of the extractant phase and the heavy component phase becomes more difficult due to the reduction in the density difference, which ultimately leads to a decrease in the recovery rate of the metal catalyst after a long period of continuous reaction.

[0025] To address this issue, in the present technical solution, after a certain period of continuous reaction time, for example, greater than or equal to 500 hours, extractant A and / or extractant B are added to the second extractant, so that the volume of extractant B is equal to or slightly greater than that of extractant A. This differs from the continuous reaction before 500 hours, in which a larger amount of extractant A is used. By increasing the proportion of extractant B, the lower extractant phase has a higher specific gravity during phase separation, thereby facilitating the separation of the first extractant phase and the first heavy component phase, as well as the separation of the heavy component residue and the second extractant phase. This allows a high metal catalyst recovery rate to be maintained even after a long period of continuous reaction.

[0026] Furthermore, the volume ratio of the first extractant to the heavy component is 1:1 to 3:1, and the volume ratio of the second extractant to the first heavy component phase is 1:1 to 3:1. Using too little extractant can affect the overall recovery of the metal catalyst, but too much extractant can also cause miscibility between the polar and less polar phases, similarly reducing catalyst recovery. Therefore, in a more preferred embodiment, the volume ratios of the extractant to the heavy component, and the second extractant to the first heavy component phase, range from 1:1 to 3:1, and more preferably, range from 1:1 to 2:1.

[0027] Furthermore, the extraction temperature of the first extractant and the heavy component is 40-60° C., and the extraction temperature of the second extractant and the first heavy component is 40-60° C. In some embodiments, the extraction time is 10-180 minutes.

[0028] Furthermore, the temperature of phase separation after extraction is -10 to 20° C. More preferably, the temperature of phase separation after extraction is -5 to 5° C.

[0029] Furthermore, the phase separation time is 10 to 180 minutes. More preferably, the phase separation time is 60 to 120 minutes.

[0030] Another object of the present invention is to provide a metal catalyst recovery system for a homogeneous hydroformylation reaction liquid, comprising a two-stage extraction structure. The first-stage extraction structure is used to separate a first heavy component phase and a first extractant phase from the heavy component of the hydroformylation reaction liquid, and to separate the majority of the metal catalyst from the second extractant phase. The remaining second extractant is used to extract a small portion of the metal catalyst contained in the first heavy component phase in the second-stage extraction structure, and is returned to the first-stage extraction structure for recycling. At the same time, the residual heavy component residue remaining after extraction is discharged from the reaction system.

[0031] The above-mentioned purpose of the present invention is achieved through the following technical solutions:

[0032] A metal catalyst recovery system for homogeneous hydroformylation reaction liquid comprises:

[0033] The first separation device is used to separate the hydroformylation reaction liquid into light components and heavy components;

[0034] a first extraction device for mixing a first extractant and the heavy component, and performing phase separation to obtain a first heavy component phase and a first extractant phase;

[0035] a second separation device for separating the metal catalyst and the second extractant from the first extractant phase;

[0036] The second extraction device is used to mix the first heavy component phase and the second extractant, and separate the phases to obtain a heavy component residual liquid and a second extractant phase. The second extractant phase is returned to the first extraction device and used as the first extractant to mix with the heavy component.

[0037] In this technical solution, the reaction liquid from the hydroformylation reactor is separated in a first separation unit to remove light components such as olefins, alkanes, and aliphatic aldehydes, leaving a heavy component residue containing the metal catalyst, also known as the heavy component. Subsequently, the heavy component containing the catalyst that has not evaporated from the bottom of the first separation unit is mixed with a first extractant and transported to the first extraction unit. After uniform stirring, the mixture is allowed to stand, cooled, and phase separated. The upper first heavy component phase is a weakly polar phase containing the heavy component residue, while the lower first extractant phase is a polar phase containing the metal catalyst. The latter phase is further separated in a second separation unit to produce a second extractant and a metal catalyst. The second extractant is transported to the second extraction unit, while the high-concentration metal catalyst residue that has not evaporated from the bottom of the second separation unit is cooled and transported to a catalyst recovery tank. Next, the first heavy component phase containing the residual liquid of the heavy components from the first extraction device is combined with the second extractant and transported to the second extraction device. After being stirred evenly, it is allowed to stand, cool down, and separate into phases. The upper weak polar phase containing the residual liquid of the heavy components is transported to the residual liquid tank for collection, and the lower second extractant phase is returned to the first extraction device. In the subsequent continuous reaction, it replaces the first extractant as the extractant of the first extraction device.

[0038] In some preferred embodiments, an extractant feeding device is further provided between the second separation device and the second extraction device. When the continuous reaction time is less than T, the extractant feeding device adds extractant A and / or extractant B to the second extractant, so that the composition and ratio of the second extractant are the same or approximately the same as those of the first extractant. When the continuous reaction time is greater than or equal to T, the extractant feeding device adds extractant A and / or extractant B to the second extractant, so that the content of extractant B in the second extractant is greater than that of extractant A, for example, the content of NMP is greater than that of DMF, thereby increasing the specific gravity of the extractant phase in the continuous reaction system. In one or more embodiments, the volume ratio of extractant B to extractant A in the added second extractant is 1 to 1.1.

[0039] Furthermore, the first extraction device includes a first extraction kettle and a first phase separator, the first extraction kettle is used to mix and extract the first extractant and the heavy component, and the first phase separator is used to separate the phases to obtain a first heavy component phase and a first extractant phase; the second extraction device includes a second extraction kettle and a second phase separator, the second extraction kettle is used to mix and extract the first heavy component phase and the second extractant, and the second phase separator is used to separate the phases to obtain a heavy component residual liquid and a second extractant phase.

[0040] In this technical solution, the extraction temperature of the first and second extraction kettles is typically 40-60°C. Any conventional extraction kettle can be used. In one or more embodiments, the first and second extraction kettles are jacketed or internally equipped with coils and agitators, providing stirring, mixing, heating, and cooling functions. After extraction, the reaction mixture is transferred to a phase separator for further phase separation, typically at a temperature between -10 and 20°C.

[0041] Furthermore, the first separation device and the second separation device may be an evaporator or a stripping tower.

[0042] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0043] 1. Based on the differences in solubility and specific gravity between the heavy components and the metal catalyst in the hydroformylation reaction solution under specific conditions, the present invention significantly improves the recovery rate of the metal catalyst without adding additional complexes to react with the catalyst through two-stage extraction and recycling of the extractant, effectively simplifies the catalyst recovery process, and reduces the catalyst recovery cost.

[0044] 2. The present invention extracts most of the catalyst in the heavy component residue in two stages and then discharges the heavy component residue from the continuous reaction system, which can significantly reduce the accumulation of heavy components in the hydroformylation cycle reaction and effectively improve the conversion rate and production efficiency of the industrial hydroformylation continuous reaction;

[0045] 3. By rationally adjusting the composition and ratio of the first extractant, the present invention can better utilize the solubility difference between the metal catalyst and the condensate to extract most of the catalyst from the heavy components, so that the total recovery rate of the metal catalyst can be maintained at above 90%;

[0046] 4. The present invention adjusts the volume ratio of extractant A and extractant B in the second extractant after a period of continuous reaction, thereby increasing the proportion of the extractant phase in the continuous reaction system, thereby solving the problem of difficulty in separating the heavy component phase and the extractant phase caused by the increase of heavy components in the system after a long reaction time. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of this application, and do not constitute a limitation of the embodiments of the present invention. In the drawings:

[0048] Figure 1 This is a flow chart of a metal catalyst recovery method according to a specific embodiment of the present invention;

[0049] Figure 2 It is a structural block diagram of the metal catalyst recovery system in a specific embodiment of the present invention. DETAILED DESCRIPTION

[0050] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with examples and drawings. The exemplary embodiments of the present invention and their descriptions are only used to explain the present invention and are not intended to limit the present invention.

[0051] All raw materials of the present invention are not particularly limited in their sources and can be purchased commercially or prepared according to conventional methods well known to those skilled in the art. All raw materials of the present invention are not particularly limited in their purity; analytically pure materials or those conventionally required in the field of hydroformylation reactions are preferably used. All raw materials of the present invention have conventional designations and abbreviations in the art, and each designation and abbreviation is clear and unambiguous within the field of its relevant application. Those skilled in the art can purchase them commercially or prepare them by conventional methods based on the designation, abbreviation, and corresponding application.

[0052] The present invention has no particular limitation on the expression of the substituents, and all expressions familiar to those skilled in the art are adopted. Based on common sense, those skilled in the art can correctly understand the meaning of the substituents according to the expressions.

[0053] Example 1:

[0054] like Figure 1 The method for recovering the metal catalyst from the homogeneous hydroformylation reaction liquid comprises the following steps:

[0055] obtaining a hydroformylation reaction liquid, removing light components from the hydroformylation reaction liquid, and obtaining a heavy component;

[0056] The heavy component and the first extractant are mixed uniformly, and phase separation is performed to obtain a first heavy component phase and a first extractant phase;

[0057] Separating the metal catalyst and the second extractant from the first extractant phase, then uniformly mixing the second extractant with the first heavy component phase, and performing phase separation to obtain a heavy component residue and a second extractant phase;

[0058] The second extractant phase serves as the first extractant mixed with the heavy components.

[0059] In some embodiments, the first extractant is composed of extractant A and extractant B, wherein extractant A is N,N-dimethylformamide or formamide, and extractant B is N-methylpyrrolidone. In some preferred embodiments, the volume ratio of extractant A to extractant B is 1.2-20.

[0060] In one or more embodiments, the separated second extractant is supplemented to maintain the same or similar composition and ratio as the first extractant. In some embodiments, the second extractant can also be adjusted to a different ratio than the first extractant as the hydroformylation reaction time increases.

[0061] In some preferred embodiments, after a certain reaction time, extractant A and / or extractant B are added so that the volume ratio of extractant B to extractant A in the second extractant is 1-1.1.

[0062] In some preferred embodiments, the volume ratio of the first extractant to the heavy component is 1:1-3:1, and the volume ratio of the second extractant to the first heavy component is 1:1-3:1.

[0063] In some embodiments, the extraction temperature of the first extractant and the heavy component is 40-60°C, and the extraction temperature of the second extractant and the first heavy component is 40-60°C.

[0064] In some embodiments, the temperature for phase separation after extraction is -10 to 20° C. In one or more embodiments, the phase separation time is 10 to 180 minutes.

[0065] Example 2:

[0066] A metal catalyst recovery system for a homogeneous hydroformylation reaction liquid, comprising:

[0067] The first separation device is used to separate the hydroformylation reaction liquid into light components and heavy components;

[0068] a first extraction device for mixing a first extractant and the heavy component, and performing phase separation to obtain a first heavy component phase and a first extractant phase;

[0069] a second separation device for separating the metal catalyst and the second extractant from the first extractant phase;

[0070] The second extraction device is used to mix the first heavy component phase and the second extractant, and separate the phases to obtain a heavy component residual liquid and a second extractant phase. The second extractant phase is returned to the first extraction device and used as the first extractant to mix with the heavy component.

[0071] In some embodiments, the first extraction device includes a first extraction kettle and a first phase separator, the first extraction kettle is used for mixing and extracting the first extractant and the heavy component, and the first phase separator is used for phase separation to obtain a first heavy component phase and a first extractant phase; the second extraction device includes a second extraction kettle and a second phase separator, the second extraction kettle is used for mixing and extracting the first heavy component phase and the second extractant, and the second phase separator is used for phase separation to obtain a heavy component residual liquid and a second extractant phase.

[0072] In some embodiments, the first separation device and the second separation device can be an evaporator or a stripping tower.

[0073] In some embodiments, the first and second separation devices are falling film evaporators or wiped film evaporators. In one or more embodiments, the evaporators are further connected to a gas-liquid separator. In further preferred embodiments, a demister is provided on top of the gas-liquid separator to prevent carryover of metal catalyst. In some embodiments, the first and second separation devices can be connected to a vacuum system or connected in a stripping mode using an inert gas such as nitrogen.

[0074] In some preferred embodiments, Figure 2 As shown, the first separation device uses a first evaporator. After the first evaporator evaporates the light components in the hydroformylation reaction liquid, the heavy components containing the catalyst at the bottom are mixed with the first extractant and transported to the first extraction kettle. After being stirred evenly, they enter the first phase separator for static, cooling, and phase separation. Among them, the first heavy component phase ( Figure 2 The upper-middle heavy component phase is a weakly polar phase containing heavy component residual liquid, and the lower-layer first extractant phase is a polar phase containing a metal catalyst. The first extractant phase enters the second evaporator. In the second evaporator, the extractant phase is evaporated and collected, and the extractant ratio is supplemented to obtain the second extractant. The high-concentration catalyst residual liquid that has not evaporated at the bottom of the second evaporator is cooled and transported to the catalyst recovery tank.

[0075] Subsequently, the first heavy component phase containing the residual heavy component from the first extraction kettle is combined with the supplemented second extractant and transported to the second extraction kettle. After being stirred evenly, it is allowed to stand in the second phase separator, cooled, and separated. The weak polar phase containing the residual heavy component from the upper layer ( Figure 2 The middle and heavy components (the residual liquid) are transported to the residual liquid tank for collection, and the second extractant phase ( Figure 2 The extractant phase (in the middle extractant phase) is returned to the first extraction kettle, and in the subsequent continuous reaction, it replaces the first extractant as the extractant of the first extraction kettle.

[0076] Example 3 to Example 10: Rhodium catalyst recovery test

[0077] Example 3:

[0078] 200 ml of the hydroformylation reaction liquid, the components of which are shown in Table 1 below, was taken and evaporated under reduced pressure in a first evaporator to remove light components. The remaining rhodium-containing heavy component 110 ml was mixed with 110 ml of a first extractant (DMF:NMP=95:5) in a 500 ml first extraction kettle and stirred at 60 degrees for 30 minutes. The mixture was then cooled to -5 to 5 degrees in a first phase separator and allowed to stand for 2 hours for phase separation. About 110 ml of the upper heavy phase (first heavy phase) was taken out and mixed with 110 ml of a second extractant in a 500 ml second extraction kettle. The second extractant had the same composition and ratio as the first extractant. The mixture was stirred at 60 degrees for 30 minutes. The mixture was then cooled to -5 to 5 degrees in a second phase separator and allowed to stand for 2 hours for phase separation. The second extractant phase containing rhodium catalyst in the lower layer was taken out and combined with the first heavy phase in the lower layer of the first extraction kettle to remove the extractant phase by reduced pressure evaporation. The rhodium content was analyzed, and the calculated rhodium recovery rate was 98.2%.

[0079] Table 1:

[0080]

[0081] Example 4:

[0082] 200 ml of the hydroformylation reaction liquid, the components of which are shown in Table 2 below, was taken and evaporated under reduced pressure in a first evaporator to remove light components. The remaining rhodium-containing heavy component, 110 ml, was mixed with 110 ml of a first extractant (DMF:NMP=55:45) in a 500 ml first extraction kettle and stirred at 60 degrees for 30 minutes. The mixture was then cooled to -5-5 degrees in a first phase separator and allowed to stand for 2 hours for phase separation. About 110 ml of the upper heavy phase (first heavy phase) was taken out and mixed with 110 ml of a second extractant in a 500 ml second extraction kettle. The second extractant had the same composition and ratio as the first extractant. The mixture was stirred at 60 degrees for 30 minutes. The mixture was then cooled to -5-5 degrees in a second phase separator and allowed to stand for 2 hours for phase separation. The second extractant phase containing rhodium catalyst in the lower layer was taken out and combined with the first heavy phase in the lower layer of the first extraction kettle to remove the extractant phase by reduced pressure evaporation. The rhodium content was analyzed, and the calculated rhodium recovery rate was 97.6%.

[0083] Table 2:

[0084]

[0085] Example 5:

[0086] 200 ml of the hydroformylation reaction liquid, the components of which are shown in Table 3 below, was taken and evaporated under reduced pressure in a first evaporator to remove light components. The remaining rhodium-containing heavy component, 110 ml, was mixed with 110 ml of a first extractant (formamide:NMP=10:1) in a 500 ml first extraction kettle and stirred at 60 degrees for 30 minutes. The mixture was then cooled to -5-5 degrees in a first phase separator and allowed to stand for 2 hours for phase separation. About 110 ml of the upper heavy phase (first heavy phase) was taken out and mixed with 110 ml of a second extractant in a 500 ml second extraction kettle. The second extractant had the same composition and ratio as the first extractant. The mixture was stirred at 60 degrees for 30 minutes. The mixture was then cooled to -5-5 degrees in a second phase separator and allowed to stand for 2 hours for phase separation. The second extractant phase containing rhodium catalyst in the lower layer was taken out and combined with the first heavy phase in the lower layer of the first extraction kettle to remove the extractant phase by reduced pressure evaporation. The rhodium content was analyzed, and the rhodium recovery rate was calculated to be 95.2%.

[0087] Table 3:

[0088]

[0089] Example 6:

[0090] 200 ml of the hydroformylation reaction liquid, the components of which are shown in Table 4 below, was taken and evaporated under reduced pressure in a first evaporator to remove light components. The remaining rhodium-containing heavy component, 110 ml, was mixed with 220 ml of a first extractant (DMF:NMP=10:1) in a 500 ml first extraction kettle and stirred at 60 degrees for 30 minutes. The mixture was then cooled to -5 to 5 degrees in a first phase separator and allowed to stand for 2 hours for phase separation. About 110 ml of the upper heavy phase (first heavy phase) was taken out and mixed with 220 ml of a second extractant in a 500 ml second extraction kettle. The second extractant had the same composition and ratio as the first extractant. The mixture was stirred at 60 degrees for 30 minutes. The mixture was then cooled to -5 to 5 degrees in a second phase separator and allowed to stand for 2 hours for phase separation. The second extractant phase containing rhodium catalyst in the lower layer was taken out and combined with the first heavy phase in the lower layer of the first extraction kettle to remove the extractant phase by reduced pressure evaporation. The rhodium content was analyzed, and the calculated rhodium recovery rate was 92.5%.

[0091] Table 4:

[0092]

[0093] Example 7:

[0094] 200 ml of the hydroformylation reaction liquid, the components of which are shown in Table 5 below, was taken and evaporated under reduced pressure in a first evaporator to remove light components. The remaining rhodium-containing heavy component, 110 ml, was mixed with 330 ml of a first extractant (DMF:NMP=10:1) in a 500 ml first extraction kettle and stirred at 60 degrees for 30 minutes. The mixture was then cooled to -5-5 degrees in a first phase separator and allowed to stand for 2 hours for phase separation. About 110 ml of the upper heavy phase (first heavy phase) was taken out and mixed with 330 ml of a second extractant in a 500 ml second extraction kettle. The second extractant had the same composition and ratio as the first extractant. The mixture was stirred at 60 degrees for 30 minutes. The mixture was then cooled to -5-5 degrees in a second phase separator and allowed to stand for 2 hours for phase separation. The second extractant phase containing rhodium catalyst in the lower layer was taken out and combined with the first heavy phase in the lower layer of the first extraction kettle, and the extractant phase was removed by reduced pressure evaporation. The rhodium content was analyzed, and the rhodium recovery rate was calculated to be 89.0%.

[0095] Table 5:

[0096]

[0097] Example 8:

[0098] 200 ml of the hydroformylation reaction liquid, the components of which are shown in Table 6 below, was taken and evaporated under reduced pressure in a first evaporator to remove light components. The remaining rhodium-containing heavy component, 110 ml, was mixed with 110 ml of a first extractant (DMF:NMP=10:1) in a 500 ml first extraction kettle and stirred at 50 degrees for 30 minutes. The mixture was then cooled to -5 to 5 degrees in a first phase separator and allowed to stand for 2 hours for phase separation. About 110 ml of the upper heavy phase (first heavy phase) was taken out and mixed with 110 ml of a second extractant in a 500 ml second extraction kettle. The second extractant had the same composition and ratio as the first extractant. The mixture was stirred at 50 degrees for 30 minutes. The mixture was then cooled to -5 to 5 degrees in a second phase separator and allowed to stand for 2 hours for phase separation. The second extractant phase containing rhodium catalyst in the lower layer was taken out and combined with the first heavy phase in the lower layer of the first extraction kettle, and the extractant phase was removed by reduced pressure evaporation. The rhodium content was analyzed, and the rhodium recovery rate was calculated to be 90.0%.

[0099] Table 6:

[0100]

[0101] Example 9:

[0102] 200 ml of the hydroformylation reaction liquid, the components of which are shown in Table 7 below, was taken and evaporated under reduced pressure in a first evaporator to remove light components. The remaining rhodium-containing heavy component, 110 ml, was mixed with 110 ml of a first extractant (DMF:NMP=9:1) in a 500 ml first extraction kettle and stirred at 60 degrees for 30 minutes. The mixture was then cooled to -5-5 degrees in a first phase separator and allowed to stand for 2 hours for phase separation. About 110 ml of the upper heavy phase (first heavy phase) was taken out and mixed with 110 ml of a second extractant having the same composition and ratio as the first extractant in a 500 ml second extraction kettle. The second extractant phase containing rhodium catalyst in the lower layer was taken out and combined with the first heavy phase in the lower layer of the first extraction kettle, and the extractant phase was removed by reduced pressure evaporation. The rhodium content was analyzed, and the rhodium recovery rate was calculated to be 95.2%.

[0103] Table 7:

[0104]

[0105] Example 10:

[0106] 200 ml of the hydroformylation reaction liquid, the components of which are shown in Table 8 below, was taken and evaporated under reduced pressure in a first evaporator to remove light components. The remaining rhodium-containing heavy component, 110 ml, was mixed with 110 ml of a first extractant (DMF:NMP=20:1) in a 500 ml first extraction kettle and stirred at 60 degrees for 30 minutes. The mixture was then cooled to -5-5 degrees in a first phase separator and allowed to stand for 2 hours for phase separation. About 110 ml of the upper heavy phase (first heavy phase) was taken out and mixed with 110 ml of a second extractant having the same composition and ratio as the first extractant in a 500 ml second extraction kettle. The second extractant phase containing rhodium catalyst in the lower layer was taken out and combined with the first heavy phase in the lower layer of the first extraction kettle, and the extractant phase was removed by reduced pressure evaporation. The rhodium content was analyzed, and the rhodium recovery rate was calculated to be 98.0%.

[0107] Table 8:

[0108]

[0109] This demonstrates that the two-stage extraction and recycling of the extractant significantly increases the recovery rate of the rhodium catalyst to 90%, without the addition of additional complexes to react with the catalyst. Furthermore, by adjusting the composition and ratio of the first extractant, the overall recovery rate of the rhodium catalyst can be increased to 98.2%, significantly reducing the cost of continuous hydroformylation production and facilitating industrial production applications.

[0110] The terms "first," "second," and so on (e.g., first separation device, second separation device, first extraction device, second extraction device, etc.) used herein are merely used to distinguish corresponding components for clarity of description and are not intended to limit any order or emphasize importance. Furthermore, the term "connected" used herein, unless otherwise specified, may refer to a direct connection or an indirect connection via other components.

[0111] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for recovering a metal catalyst from a homogeneous hydroformylation reaction solution, characterized in that: The following steps are involved: obtaining a hydroformylation reaction liquid, removing light components from the hydroformylation reaction liquid, and obtaining a heavy component; The heavy component and the first extractant are mixed uniformly, and phase separation is performed to obtain a first heavy component phase and a first extractant phase; Separating the metal catalyst and the second extractant from the first extractant phase, then uniformly mixing the second extractant with the first heavy component phase, and performing phase separation to obtain a heavy component residue and a second extractant phase; The second extractant phase serves as the first extractant mixed with the heavy components.

2. The method for recovering a metal catalyst from a homogeneous hydroformylation reaction liquid according to claim 1, wherein: The first extractant consists of extractant A and extractant B, wherein the extractant A is N,N-dimethylformamide or formamide, and the extractant B is N-methylpyrrolidone.

3. The method for recovering a metal catalyst from a homogeneous hydroformylation reaction liquid according to claim 2, wherein: The volume ratio of the extractant A to the extractant B in the first extractant is 1.2-20.

4. The method for recovering a metal catalyst from a homogeneous hydroformylation reaction liquid according to claim 3, wherein: After a certain reaction time, extractant A and / or extractant B are added so that the volume ratio of extractant B to extractant A in the second extractant is 1-1.

1.

5. The method for recovering a metal catalyst from a homogeneous hydroformylation reaction liquid according to claim 1, wherein: The volume ratio of the first extractant to the heavy component is 1:1-3:1, and the volume ratio of the second extractant to the first heavy component is 1:1-3:

1.

6. The method for recovering a metal catalyst from a homogeneous hydroformylation reaction solution according to any one of claims 1 to 5, characterized in that: The extraction temperature of the first extractant and the heavy component is 40-60°C, and the extraction temperature of the second extractant and the first heavy component is 40-60°C.

7. The method for recovering a metal catalyst from a homogeneous hydroformylation reaction solution according to any one of claims 1 to 5, characterized in that: The temperature of phase separation after extraction is -10~20°C.

8. A metal catalyst recovery system for homogeneous hydroformylation reaction liquid, characterized in that: include: The first separation device is used to separate the hydroformylation reaction liquid into light components and heavy components; a first extraction device for mixing a first extractant and the heavy component, and performing phase separation to obtain a first heavy component phase and a first extractant phase; a second separation device for separating the metal catalyst and the second extractant from the first extractant phase; The second extraction device is used to mix the first heavy component phase and the second extractant, and separate the phases to obtain a heavy component residual liquid and a second extractant phase. The second extractant phase is returned to the first extraction device and used as the first extractant to mix with the heavy component.

9. The metal catalyst recovery system for homogeneous hydroformylation reaction liquid according to claim 8, characterized in that: The first extraction device includes a first extraction kettle and a first phase separator, the first extraction kettle is used for mixing and extracting the first extractant and the heavy component, and the first phase separator is used for phase separation to obtain a first heavy component phase and a first extractant phase; the second extraction device includes a second extraction kettle and a second phase separator, the second extraction kettle is used for mixing and extracting the first heavy component phase and the second extractant, and the second phase separator is used for phase separation to obtain a heavy component residual liquid and a second extractant phase.

10. The metal catalyst recovery system for homogeneous hydroformylation reaction liquid according to claim 8, characterized in that: The first separation device and the second separation device can be an evaporator or a stripping tower.

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