Process and apparatus for the continuous production of aldehydes by hydroformylation

Abstract

The application provides a method and device for continuously preparing aldehyde compounds through a hydroformylation reaction. The method for continuously preparing aldehyde compounds through the hydroformylation reaction comprises the following steps: using a catalyst to catalyze an olefin raw material and synthetic gas to perform a hydroformylation reaction, so as to obtain a reaction product containing aldehyde compounds; and separating the reaction product, so as to obtain the aldehyde compounds and recover the catalyst. The hydroformylation reaction comprises a homogeneous reaction or a heterogeneous reaction. The method can solve the problem of a large amount of catalyst loss in the hydroformylation reaction in the prior art and is suitable for the field of Fischer-Tropsch synthesis.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of Fischer-Tropsch synthesis, in particular to a method and device for continuously preparing aldehyde compounds through hydroformylation reaction BACKGROUND

[0002] Fischer-Tropsch synthesis technology refers to a reaction of producing hydrocarbons through chain growth under the action of a catalyst by taking synthetic gas (CO and H2) as raw materials. The process has simple raw materials, but the reaction products are relatively complex, and various organic compounds such as chain alkanes, alkenes, alcohols, aldehydes and acids can be produced, and the carbon number distribution of the products is relatively wide. It is a process of converting coal, natural gas and biomass and other raw materials into liquid fuels and high value-added chemicals through synthetic gas.

[0003] Typical Fischer-Tropsch synthesis process includes synthetic gas (including gas making and purification), Fischer-Tropsch synthesis reaction and synthetic oil product processing and refining. The Fischer-Tropsch synthesis technology of Sasol Company in South Africa has been in a leading position for a long time, and other companies such as Shell, Exxon Mobil also have relatively mature Fischer-Tropsch synthesis technology. The impurity content of Fischer-Tropsch synthesis oil is low, and the emission pollutants of combustion are less. It can be predicted that Fischer-Tropsch synthesis technology will play an increasingly important role in the production of clean fuel in the future.

[0004] High carbon alcohol, also known as high fatty alcohol or high alcohol, refers to a mixture of monohydric alcohols containing six or more carbon atoms. It is the main basic raw material for synthesizing surfactants, detergents, plasticizers and other various fine chemicals, and its processing products are widely used in the fields of textiles, papermaking, food, medicine and the like. Alkanes prepared by Fischer-Tropsch synthesis can be prepared into aldehydes through hydroformylation reaction, and high carbon alcohol can be prepared by hydrogenation reaction of aldehyde. However, in the existing hydroformylation reaction, the hydroformylation catalyst cannot be recycled and utilized, the loss amount is large, and the production cost is high. SUMMARY

[0005] The main purpose of the present application is to provide a method and device for continuously preparing aldehyde compounds through hydroformylation reaction, so as to solve the problem of large catalyst loss in the existing hydroformylation reaction.

[0006] In order to achieve the above purpose, according to the first aspect of the present application, a method for continuously preparing aldehyde compounds through hydroformylation reaction is provided, which comprises: using a catalyst to catalyze the hydroformylation reaction of olefin raw material and synthetic gas, and obtaining reaction products containing aldehyde compounds; separating the reaction products to obtain the aldehyde compounds and recycling the catalyst at the same time; the hydroformylation reaction includes homogeneous reaction or heterogeneous reaction.

[0007] Further, the hydroformylation reaction is a homogeneous reaction, and the separation comprises separating the aldehyde compound and the catalyst by evaporation; preferably, the separation comprises: subjecting the reaction product to a first evaporation to separate unreacted olefins from the reaction product, thereby obtaining a mixture of the aldehyde compound and the catalyst; and subjecting the mixture of the aldehyde compound and the catalyst to a second evaporation to obtain the aldehyde compound and the catalyst, respectively; preferably, the aldehyde compound obtained by the homogeneous reaction has a carbon number of C5-C10; preferably, the evaporation comprises wiped film evaporation, the first evaporation comprises a first wiped film evaporation, and the second evaporation comprises a second wiped film evaporation; the first wiped film evaporation is performed at a temperature of 40-80℃ and a pressure of 5-101.325kPa; the second wiped film evaporation is performed at a temperature of 50-100℃ and a pressure of 1-20kPa; preferably, the evaporation area of the first wiped film evaporation and / or the second wiped film evaporation is 0.1-1m 2 ; preferably, the feeding amount of the first wiped film evaporation and / or the second wiped film evaporation is 300-500mL / h; preferably, the rotation speed of the first wiped film evaporation and / or the second wiped film evaporation is 100-300r / min; preferably, the residence time of the first wiped film evaporation and / or the second wiped film evaporation is 20-40s.

[0008] Further, the hydroformylation reaction is a heterogeneous reaction, and the separation comprises separating the aldehyde compound and the catalyst by using an oil-water separator; preferably, the aldehyde compound obtained by the heterogeneous reaction has a carbon number of C9-C20.

[0009] Further, the synthesis gas is CO and H2; preferably, the catalyst comprises a combined catalyst comprising a complex of a metal and an organophosphorus ligand; preferably, the metal comprises rhodium; preferably, the organophosphorus ligand comprises a monophosphorus ligand or a diphosphorus ligand.

[0010] Further, the concentration of the catalyst is 100-300ppm; preferably, the pressure of the hydroformylation reaction is 5-50kPa; preferably, the temperature of the hydroformylation reaction is 80-110℃; preferably, the time of the hydroformylation reaction is 0.5-24h.

[0011] Further, the olefin raw material comprises a Fischer-Tropsch synthesis oil raw material; the Fischer-Tropsch synthesis oil raw material is a fraction with a distillation range of C5-C20; preferably, the Fischer-Tropsch synthesis oil raw material comprises 25-40% of alkanes, 35-60% of normal olefins, 1-25% of isomeric olefins, and 0.1-2% of oxygen-containing compounds by mass fraction; preferably, the hydroformylation reaction occurs in a solvent, and the solvent comprises one or more of toluene, PEG, DOP, or water; preferably, the volume ratio of the Fischer-Tropsch synthesis oil raw material to the solvent is 1:1-2.

[0012] In order to achieve the above-mentioned purpose, according to a second aspect of the present application, there is provided a method for preparing a higher alcohol, comprising: preparing an aldehyde compound by using the method for continuously preparing an aldehyde compound by a hydroformylation reaction, and then sequentially performing hydrogenation and purification on the aldehyde compound to obtain the higher alcohol.

[0013] In order to achieve the above-mentioned purpose, according to a third aspect of the present application, there is provided a device for continuously preparing an aldehyde compound by a hydroformylation reaction, comprising a reaction unit and a separation unit; the reaction unit comprises a reaction container, and the reaction container is provided with an olefin raw material feeding port, a synthesis gas feeding port, a catalyst feeding port and a discharge port; the separation unit comprises a separator, and the separator is provided with a product feeding port, a product discharge port and a catalyst return port; the discharge port of the reaction container is in communication with the product feeding port of the separator, and the catalyst return port of the separator is in communication with the catalyst feeding port of the reaction container.

[0014] Further, the separator comprises an evaporator and / or an oil-water separator; preferably, the evaporator and the oil-water separator are independently provided, and are respectively in communication with the discharge port of the reaction container, and a valve is arranged on the communication path; preferably, the evaporator comprises a wiped film evaporator or a falling film evaporator; more preferably, the evaporation area of the wiped film evaporator is 0.1-1 m 2 ; preferably, the wiped film evaporator comprises a first wiped film evaporator and a second wiped film evaporator, the first wiped film evaporator is provided with a product feeding port, a first discharge port and a gas phase outlet, and the second wiped film evaporator is provided with a second feeding port, a product discharge port and a catalyst return port; the product feeding port of the first wiped film evaporator is in communication with the discharge port of the reaction container, and the first discharge port of the first wiped film evaporator is in communication with the second feeding port of the second wiped film evaporator.

[0015] In order to achieve the above-mentioned purpose, according to a fourth aspect of the present application, there is provided a device for preparing a higher alcohol, comprising a device for preparing an aldehyde compound, a hydrogenation reaction device and a purification device which are sequentially and serially arranged, wherein the device for preparing an aldehyde compound adopts the device for continuously preparing an aldehyde compound by a hydroformylation reaction.

[0016] By applying the technical solution of the present application, after the aldehyde compound is obtained by the hydroformylation reaction, the reaction product containing the aldehyde compound is separated, the catalyst can be recycled, and the loss amount of the catalyst in the reaction is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0017] The accompanying drawings, which form a part of the present application, are used to provide further understanding of the present application, and the illustrative embodiments of the present application and their descriptions are used to explain the present application, and do not constitute improper limitations on the present application. In the drawings:

[0018] Figure 1A structure diagram of an oil-water separator according to an embodiment of the present application is shown;

[0019] Figure 2 A schematic diagram of a hydroformylation reaction device according to an embodiment of the present application is shown;

[0020] In the above drawings, the following reference signs are used:

[0021] In the above drawings, the following reference signs are used: DETAILED DESCRIPTION

[0022] It should be noted that the embodiments and features in the present application can be combined with each other without conflict. The present application will be described in detail below with reference to the embodiments.

[0023] As mentioned in the background, the loss of catalyst in the prior art hydroformylation reaction is large, which increases the production cost. In the present application, the inventors try to develop a new method for continuously preparing aldehyde compounds by hydroformylation reaction, so as to reduce the loss of catalyst in the hydroformylation reaction, and thus a series of protection schemes of the present application are proposed.

[0024] In a first typical embodiment of the present application, a method for continuously preparing aldehyde compounds by hydroformylation reaction is provided, which comprises: using a catalyst to catalyze the hydroformylation reaction of an olefin raw material and synthesis gas to obtain a reaction product containing aldehyde compounds, and separating the reaction product to obtain aldehyde compounds and catalyst; the hydroformylation reaction comprises a homogeneous reaction or a heterogeneous reaction.

[0025] In the above method, under the catalysis of the catalyst, the olefin raw material and the synthesis gas undergo the hydroformylation reaction to produce a reaction product containing aldehyde compounds; and the reaction product is separated to realize the recovery of the catalyst and the aldehyde compounds, thereby reducing the loss of catalyst in the hydroformylation reaction. The above hydroformylation reaction comprises a homogeneous reaction or a heterogeneous reaction. The homogeneous reaction is that the olefin raw material and the catalyst react in the same phase; in the heterogeneous reaction (multiphase reaction), the phases of the olefin raw material and the catalyst are different.

[0026] In a preferred embodiment, the hydroformylation reaction is a homogeneous reaction, and the separation comprises separating the aldehyde compound and the catalyst by evaporation; preferably, the separation comprises: subjecting the reaction product to a first evaporation to separate the unreacted olefin from the reaction product, to obtain a mixture of the aldehyde compound and the catalyst; and subjecting the mixture of the aldehyde compound and the catalyst to a second evaporation to obtain the aldehyde compound and the catalyst, respectively; preferably, the aldehyde compound obtained from the homogeneous reaction has a carbon number of C5-C10; preferably, the evaporation comprises wiped film evaporation, the first evaporation comprises a first wiped film evaporation, and the second evaporation comprises a second wiped film evaporation, the first wiped film evaporation is performed at a temperature of 40-80℃ and a pressure of 5-101.325kPa; preferably, the second wiped film evaporation is performed at a temperature of 50-100℃ and a pressure of 1-20kPa; preferably, the evaporation area of the first wiped film evaporation and / or the second wiped film evaporation is 0.1m2; preferably, the feeding amount of the first wiped film evaporation and / or the second wiped film evaporation is 300-500mL / h; preferably, the rotation speed of the first wiped film evaporation and / or the second wiped film evaporation is 300r / min; preferably, the residence time of the first wiped film evaporation and / or the second wiped film evaporation is 20-40s. 2

[0027] If the hydroformylation reaction is a homogeneous reaction, the aldehyde compound, the unreacted substrate (i.e. the unreacted olefin) and the catalyst can be separated from the reaction product by wiped film evaporation after obtaining the reaction product, to achieve the separation of the aldehyde compound and the recovery of the catalyst. The reaction product obtained from the hydroformylation reaction in a homogeneous reaction is one or more aldehyde compounds having a carbon number of C5, C6, C7, C8, C9 or C10, or a fraction segment comprising 2, 3 or 4 adjacent components. For the aldehyde compound having a smaller carbon number, the boiling point is lower, and the effect of separating the aldehyde compound and the catalyst by evaporation is better, and the separation can be achieved at a lower temperature. If the temperature is too low, the product is easy to remain in the catalyst, affecting the catalyst concentration; if the temperature is too high, the catalyst is easy to be deactivated, reducing the efficiency of repeated use. In the first evaporation, the evaporation temperature is preferably not less than 35℃ at normal pressure. In the second evaporation, the temperature is preferably not higher than 120℃, and higher than 120℃ increases the probability of catalyst deactivation.

[0028] ​Preferably, the separation of the aldehyde compound, unreacted substrate and catalyst can be better achieved by using twice wiped film evaporation, and the loss of catalyst can be reduced. In the first wiped film evaporation process, the unreacted substrate and the alkane possibly mixed in the substrate can be separated from the liquid phase in the form of gas phase. In the second wiped film evaporation process, the aldehyde compound can be separated from the liquid phase in the form of gas phase, so that the target product aldehyde compound is separated, and the remaining liquid phase is the mother liquor containing the catalyst. The mother liquor is recycled back to the hydroformylation reaction to realize the recycling of the catalyst and reduce the loss of the catalyst. In the above first and second wiped film evaporation, by twice wiped film evaporation, the temperature of separation can be controlled at a lower level, so that the catalyst is prevented from being denatured and deactivated due to continuous high temperature operation, and the effect of reducing the loss of the catalyst is further achieved. By using the above method, the loss rate of the catalyst can be controlled to be ≤0.2% after 45 days of reaction. The loss of the catalyst in the present application is calculated based on the content of the catalyst in the product (i.e. the aldehyde compound), which is regarded as the loss amount of the catalyst. The loss rate of the catalyst is measured every day to obtain the loss rate of the catalyst on that day. With the extension of the running days, the overall trend of the loss of the catalyst is gradually increasing. The loss of the catalyst is still ≤0.2% after 45 days of operation, which indicates that the operation is stable, the loss amount of the catalyst is small, and the stable production can be ensured.

[0029] The homogeneous catalyst recovery system adopts two-stage negative pressure wiped film evaporators, and the wiped film evaporator is used to form a film. The operation pressure of the first evaporator is slightly higher. The remaining hydrocarbon components in the carbonylation product are evaporated in the first evaporator, the evaporated gas phase is recovered after condensation and separation, and the incondensable gas is vented. The liquid phase in the first evaporator enters the second evaporation system to recover the aldehyde product. The liquid phase that is not vaporized in the two-stage evaporation is the catalyst mother liquor, which is pumped into the catalyst preparation tank by a catalyst circulating pump for recycling.

[0030] In a preferred embodiment, the hydroformylation reaction is a heterogeneous reaction, and the separation includes separating the aldehyde compound and the catalyst by using an oil-water separator. Preferably, the carbon number of the aldehyde compound obtained by the heterogeneous reaction is C9-C20. The reaction product obtained by the above-mentioned heterogeneous hydroformylation reaction is one or more of C9, C10, C11, C12, C13, C14, C15, C16, C17, C18, C19 or C20, or a fraction segment composed of 2, 3, 4, 5 or 6 adjacent carbon numbers. For the aldehyde compound with a larger carbon number, the boiling point is higher, and the separation effect of the catalyst is better by using the oil-water separation method, so as to prevent the high separation temperature from affecting the activity of the catalyst.

[0031] In the heterogeneous reaction, the olefin raw material and the catalyst are in different phases, i.e. the aldehyde compound obtained by the hydroformylation reaction and the catalyst are in different phases, and the catalyst and the aldehyde compound are respectively located in a first liquid phase and a second liquid phase, wherein the density of the first liquid phase is greater than that of the second liquid phase. The oil-water separator with a structure as shown in Figure 1 can realize the separation of the aldehyde compound and the catalyst. After the reaction product (i.e. the reaction product containing the aldehyde compound) passes through the oil-water separator, due to the stratification of the first liquid phase and the second liquid phase, the first liquid phase is located below the second liquid phase, the catalyst can flow out from the position of the catalyst phase in Figure 1 , and the second liquid phase reaches a certain height and enters the adjacent chamber, and the aldehyde compound flows out from the position of the aldehyde compound in Figure 1 , and the gas phase such as tail gas in the reaction product is discharged through the port located above the oil-water separator.

[0032] If a water-soluble catalyst is used, the reaction product is an oil-water two-phase product, which is subjected to decompression and cooling and then enters the oil-water separator, and the non-condensable gas is discharged to maintain the stable pressure. The water phase containing the catalyst is pumped into the catalyst preparation tank by a catalyst circulating pump for recycling.

[0033] In a preferred embodiment, the synthesis gas is CO and H2; the catalyst comprises a combination catalyst comprising a complex of a metal and an organophosphorus ligand; preferably, the metal comprises rhodium; preferably, the organophosphorus ligand comprises a monophosphorus ligand or a biphosphorus ligand.

[0034] Currently, there are two kinds of catalysts widely used in the hydroformylation reaction, i.e. cobalt-based catalysts and rhodium phosphine complex catalysts. The advantages of the rhodium phosphine catalysts are as follows: (1) the rhodium catalyst has high catalytic activity, and the reaction can be carried out at a relatively low pressure and temperature; (2) the normal aldehyde selectivity is high; (3) the problem of rhodium loss is solved, and the industrial production has higher economic benefits. However, such catalysts are heat-sensitive, and it is difficult to separate the high-carbon olefins (C10 and larger carbon number olefins) after the reaction from the catalysts.

[0035] The monophosphorus ligand, i.e. the monodentate phosphine ligand, includes but is not limited to triphenylphosphine triphenylphosphine tris(2,4-di-tert-butyl)phenylphosphite , etc. The biphosphorus ligand, i.e. the bidentate phosphine ligand, includes but is not limited to BiPhePhos Xantphos The use of the above-mentioned catalysts for the hydroformylation of olefin feedstocks is a relatively mature existing technology, and those skilled in the art can flexibly select catalysts from the existing technology to carry out the above-mentioned hydroformylation reaction. In the embodiments of this application, the combined catalyst used is a complex formed by rhodium and an organophosphorus ligand.

[0036] In a preferred embodiment, the catalyst concentration is 100-300 ppm; preferably, the hydroformylation reaction pressure is 5-50 kPa; preferably, the hydroformylation reaction temperature is 80-110 °C; preferably, the hydroformylation reaction time is 0.5-24 h.

[0037] The reagents, parameters, and conditions used in the above hydroformylation reaction are all existing synthetic conditions and can be flexibly adjusted according to different reactants and reaction scales. All conditions enable the catalytic reaction of syngas and olefin feedstocks to obtain aldehydes. For complex mixtures, such as Fischer-Tropsch synthesis oil feedstocks containing alkanes, n-olefins, isoolefins, and oxygen-containing compounds, the above hydroformylation reaction can also catalytically generate aldehydes from olefins. The alkanes and other components in the feedstock can be easily separated from the aldehydes after the reaction. In the above reaction, the temperature of the hydroformylation reaction is controlled at 80-110℃ to prevent catalyst deactivation and loss due to excessively high temperatures.

[0038] In the above reaction, the hydroformylation reaction can be carried out in one container; it can also be carried out in two or more containers. Operations in two or more containers include, but are not limited to, continuous series operation or individual batch operation. In continuous series operation, multiple reaction containers are connected in series; in individual batch operation, multiple reaction containers are connected in parallel. If two containers are used for continuous series operation, the reaction operation includes, but is not limited to: syngas from the gas phase buffer tank of the first reaction enters from the bottom of the first reactor, and the catalyst and feedstock enter from the top of the first reactor. Under the conditions of catalyst and stirring, the olefin undergoes carbonylation (i.e., hydroformylation) with the syngas. The remaining syngas enters the gas phase buffer tank of the second reaction through the top of the reactor and mixes with the fresh syngas from the second reaction. The liquid phase from the first reactor is discharged from the bottom and enters the second reactor. A cooler and a gas-liquid separator are installed at the top gas phase discharge line of the second reactor. The cooled liquid phase is returned to the reactor, and the remaining gas phase is discharged back to the gas phase buffer tank of the first reaction through a pressure regulating valve group, mixing with the fresh syngas from the first reaction, thus achieving gas recovery and utilization, reducing production energy consumption and costs. The liquid phase product at the bottom of the second reactor enters the separation unit for the separation of aldehyde compounds and catalyst recovery.

[0039] In a preferred embodiment, the olefin feedstock comprises a Fischer-Tropsch synthesis oil feedstock; the Fischer-Tropsch synthesis oil feedstock is a fraction with a distillation range of C5-C20; preferably, the Fischer-Tropsch synthesis oil feedstock comprises 25-40% of alkanes, 35-60% of normal olefins, 1-25% of isomeric olefins and 0.1-2% of oxygen-containing compounds by mass fraction; preferably, the volume ratio of the Fischer-Tropsch synthesis oil feedstock to the solvent is 1:1-2.

[0040] In the above-described hydroformylation reaction, CO and H2 are used as the synthesis gas, which can react with the olefins under the catalysis of the catalyst. Preferably, the olefin feedstock comprises a Fischer-Tropsch synthesis oil feedstock containing alkanes, olefins and the like, in the above-described reaction, the olefins react with the synthesis gas to produce aldehydes, the alkanes do not participate in the reaction and have a large difference in boiling point from the aldehydes, and thus can be easily separated from the aldehyde compounds. The components of the above-described Fischer-Tropsch synthesis oil feedstock include but are not limited to one or more of C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17, C18, C19 or C20, and also include a fraction containing 2, 3, 4, 5 or 6 components adjacent in carbon number.

[0041] In a second typical embodiment of the present application, a preparation method of a higher alcohol is provided, which comprises: preparing an aldehyde compound by the above-described method, and then sequentially performing hydrogenation and purification on the aldehyde compound to obtain a higher alcohol.

[0042] The higher alcohol is also known as a higher fatty alcohol or a higher alcohol, which refers to a mixture of monohydric alcohols containing six or more carbon atoms. On the basis of the above-described method for continuously preparing aldehyde compounds by hydroformylation reaction, the prepared aldehyde compounds can be further hydrogenated and purified by a rectification method or the like to obtain a higher alcohol.

[0043] In a third typical embodiment of the present application, a device for continuously preparing aldehyde compounds by hydroformylation reaction is provided, which comprises a reaction unit and a separation unit; the reaction unit comprises a reaction container and an olefin feedstock feeding port, a catalyst feeding port, a synthesis gas feeding port and a discharge port which are in communication with the reaction container; the separation unit comprises a separator and a product feeding port, a product discharge port and a catalyst return port which are in communication with the separator; the discharge port of the reaction unit is in communication with the product feeding port of the separation unit, and the catalyst return port of the separation unit is in communication with the catalyst feeding port of the reaction unit.

[0044] In the above-described reaction unit, the reaction unit is used for hydroformylation reaction, the olefin feedstock feeding port, the catalyst feeding port and the synthesis gas feeding port are respectively used for inputting the olefin feedstock, the catalyst and the synthesis gas into the reaction container, and the discharge port is used for outputting the reaction product after the completion of the hydroformylation.

[0045] The separator is used to separate the reaction product of the completed hydroformylation, and the target product aldehyde compound and the catalyst are obtained by separation, so that the target product with high purity is obtained, the catalyst is recycled, and the loss of the catalyst is reduced. The product feed port is used to input the reaction product of the completed hydroformylation into the separator, so that the outlet of the reaction unit is communicated with the product feed port of the separation unit; the product outlet is used to output the target product aldehyde compound obtained by separation; and the catalyst reflux port is used to output the recycled catalyst, and the catalyst reflux port is communicated with the catalyst feed port of the reaction unit, so that the recycled catalyst is transported to the reaction unit, and the recycling of the catalyst is realized.

[0046] In a preferred embodiment, the separator comprises an evaporator and / or an oil-water separator; preferably, the evaporator and the oil-water separator are independently arranged, and are respectively communicated with the outlet of the reaction container, and a valve is arranged on the communication path; preferably, the evaporator comprises but is not limited to a wiped film evaporator or a falling film evaporator; more preferably, the evaporation area of the wiped film evaporator is 0.1-1 m 2 ; preferably, the wiped film evaporator comprises a first wiped film evaporator and a second wiped film evaporator; the first wiped film evaporator is provided with a product feed port, a first outlet and a gas phase outlet, and the second wiped film evaporator is provided with a second feed port, a product outlet and a catalyst reflux port; the product feed port of the first wiped film evaporator is communicated with the outlet of the reaction container, and the first outlet of the first wiped film evaporator is communicated with the second feed port of the second wiped film evaporator.

[0047] In the above device, the separator comprises an evaporator and / or an oil-water separator, the evaporator is used to separate the reaction product of the homogeneous hydroformylation, and the oil-water separator is used to separate the reaction product of the heterogeneous hydroformylation. In the above device, one of the separators can be arranged, that is, only the evaporator or the oil-water separator is arranged, and the device is used to respectively implement the homogeneous reaction or the heterogeneous reaction; or the evaporator and the oil-water separator are simultaneously arranged in the device, the reaction product is controlled to be input into the evaporator for separation when the homogeneous reaction is performed, and the reaction product is controlled to be input into the oil-water separator for separation when the heterogeneous reaction is performed. The flow direction of the reaction product can be controlled through the valve. The device provided with the evaporator and the oil-water separator can perform the homogeneous hydroformylation and the heterogeneous hydroformylation, and can separate the reaction product, so that the target product aldehyde compound is generated and the catalyst is recycled.

[0048] Further, the evaporator comprises a wiped film evaporator, and two wiped film evaporators can be provided, a first wiped film evaporator is used to separate unreacted olefins and components (such as alkanes) in the reaction raw materials that do not participate in the hydroformylation reaction from the reaction product, and the first wiped film evaporator is discharged from the gas phase outlet. The product inlet of the first wiped film evaporator is used to input the reaction product into the first wiped film evaporator, and the first outlet is used to output the mixture of aldehyde compounds and catalyst into the second wiped film evaporator. The second wiped film evaporator is used to separate the mixture of aldehyde compounds and catalyst, the second inlet is in communication with the first outlet, and is used to output the mixture of aldehyde compounds and catalyst into the second wiped film evaporator. The product outlet and the catalyst reflux outlet are respectively used to output the aldehyde compounds and the catalyst.

[0049] In the above device, by providing the reaction unit and the separation unit, the preparation of aldehyde compounds and the separation and reuse of the catalyst can be realized. Figure 2 A hydroformylation reaction device is shown, wherein: 1-first hydroformylation reactor, 2-second hydroformylation reactor, 3-first stage wiped film evaporator, 4-first stage evaporation vapor-liquid separator, 5-first stage evaporation condenser, 6-second stage wiped film evaporator, 7-second stage evaporation vapor-liquid separator, 8-second stage evaporation condenser, 9-vacuum pump, 10-feed gas buffer tank, 11-feed buffer tank, 12-catalyst preparation tank, 13-catalyst tank, 14-condenser, 15-gas-liquid separator, 16-oil-water separator, 17-aldehyde product buffer tank, 18-first stage evaporation collection tank, 19-second stage evaporation collection tank, 20-catalyst buffer tank. The hydroformylation reaction device in the present application includes but is not limited to Figure 2 The device shown.

[0050] The above first stage evaporation condenser and second stage evaporation condenser can condense and collect everything in the gas phase except non-condensable gas. The purpose of the first stage evaporation vapor-liquid separator and the second stage evaporation vapor-liquid separator is to separate the gas phase and the liquid phase, wherein the gas phase in the first stage evaporation vapor-liquid separator is alkanes, and the liquid phase is a mixture of aldehyde products and catalyst; the gas phase in the second stage evaporation vapor-liquid separator is aldehyde products, and the liquid phase is catalyst, so as to realize the separation of the reaction product and the catalyst.

[0051] In the fourth typical embodiment of the present application, a device for preparing high carbon alcohol is provided, which comprises a device for preparing aldehyde compounds, a hydrogenation reaction device and a purification device arranged in series, wherein the device for preparing aldehyde compounds adopts the above-mentioned hydroformylation reaction continuous device for preparing aldehyde compounds.

[0052] On the basis of the above-mentioned aldehyde compound hydroformylation reaction device, further sequentially connecting the hydrogenation reaction device, purification device and collection device, the aldehyde compound output from the hydroformylation reaction device can be hydrogenated to obtain a mixture of high carbon alcohol; further using the purification device, including but not limited to rectification device, realizing the separation of different kinds of high carbon alcohol.

[0053] The beneficial effects of the present application will be further explained in detail below in conjunction with specific examples.

[0054] Example 1

[0055] The raw material is C5 component cut by rectification, the olefin content is 67% (of which n-olefin is 44.7%, isoolefin is 22.3%), the alkane content is 28%, the oxygen-containing compound is 1.2%, and the other (non-C5 component such as C4 component) is 3.8%. The catalyst is rhodium and ligand triphenylphosphine. The catalyst (rhodium) used in this example and the following examples is produced by Xi'an Kelixin Material Co., Ltd., and the ligand is produced by Suzhou Jinyuan Fine Chemical Co., Ltd. In actual application, other sources of catalyst can also be flexibly selected for preparation. The solvent is toluene, which is added to the high-pressure reaction kettle in a certain proportion, wherein the mass ratio of catalyst to ligand is 1:5, the volume ratio of raw material to toluene is 1:1, and the catalyst concentration is 80 ppm. The kettle is purged with synthesis gas (CO:H2=1:1 (volume ratio)) for 5 times, the synthesis gas is continuously introduced and the pressure in the kettle is maintained at 1 MPa, the temperature is raised to 85℃, and the reaction time is 1 h. The reaction product enters the evaporator for separation, the first-stage evaporator operates at normal pressure, the operating temperature is 40℃, the second-stage evaporator operates at a pressure of 10 KPa, the operating temperature is 65℃, and the olefin conversion rate is 76%, the n-olefin conversion rate is 97.6%, the yield is 72%, and the catalyst loss is 0.102% after 45 days of reaction, which is detected by gas chromatograph (Shimadzu GC-2014).

[0056] Example 2

[0057] The raw material is C6 component cut by rectification, the olefin content is 59% (of which normal olefin is 41.1%, isomeric olefin is 17.9%), the alkane content is 38%, the oxygen-containing compound is 0.8%, and the others (components other than C6, such as C5 component) is 2.2%. The catalyst is rhodium and the ligand is triphenyl phosphite, the solvent is toluene, and they are added into the high-pressure reaction kettle in a certain proportion, in which the mass ratio of the catalyst to the ligand is 1:5, the volume ratio of the raw material to toluene is 1:1, and the catalyst concentration is 100 ppm. The kettle is purged with synthesis gas (CO:H2=1:1 (volume ratio)) for 5 times, the synthesis gas is continuously introduced, the pressure in the kettle is kept at 1 MP, the temperature is raised to 85°C, and the reaction lasts for 2 h. The reaction product enters the evaporator for separation, the first-stage evaporator operates at 50 KPa, the operating temperature is 45°C, the second-stage evaporator operates at 10 KPa, the operating temperature is 65°C, and the analysis and detection by the gas chromatograph show that the olefin conversion rate is 83%, the normal olefin conversion rate is 98.3%, the yield is 79%, and the catalyst loss is 0.124% when the reaction lasts for 45 days.

[0058] Example 3

[0059] The raw material is C5-C7 component cut by rectification, the olefin content is 60% (of which normal olefin is 42.7%, isomeric olefin is 17.3%), the alkane content is 36%, the oxygen-containing compound is 1.9%, and the others (components other than C5-C7, such as C4 component) is 2.1%. The catalyst is rhodium and the ligand is triphenyl phosphine, the solvent is toluene, and they are added into the high-pressure reaction kettle in a certain proportion, in which the mass ratio of the catalyst to the ligand is 1:5, the volume ratio of the raw material to toluene is 1:1, and the catalyst concentration is 180 ppm. The kettle is purged with synthesis gas (CO:H2=1:1 (volume ratio)) for 5 times, the synthesis gas is continuously introduced, the pressure in the kettle is kept at 2 MP, the temperature is raised to 90°C, and the reaction lasts for 4 h. The reaction product enters the evaporator for separation, the first-stage evaporator operates at 50 KPa, the operating temperature is 60°C, the second-stage evaporator operates at 10 KPa, the operating temperature is 75°C, and the analysis and detection by the gas chromatograph show that the olefin conversion rate is 87%, the normal olefin conversion rate is 99%, the yield is 86%, and the catalyst loss is 0.187% when the reaction lasts for 45 days.

[0060] Example 4

[0061] The raw material is C11-C12 component cut by rectification, the olefin content is 68% (of which the normal olefin is 42% and the isomerized olefin is 26%), the alkane content is 26%, the oxygen-containing compound is 1.6%, and the other (non-C11-C12 component such as C10 component) is 4.4%. The catalyst is rhodium and the ligand is triphenylphosphine, the solvent is PEG-400 solution and water, the solvent and the raw material are added into the high-pressure reaction kettle with stirring in a volume ratio of 1:1, the mass ratio of PEG to water is 4:1, the mass ratio of the catalyst to the ligand is 1:8, and the catalyst concentration is 260 ppm. The kettle is purged with synthetic gas (CO:H2=1:1 (volume ratio)) for 5 times, the synthetic gas is continuously introduced to maintain the pressure in the kettle at 2 MP, the temperature is raised to 105°C, the stirring reaction time is 5 h, the reaction is stopped, and the oil-water two-phase separator is used for separation. The gas chromatograph analysis shows that the olefin conversion rate is 68%, the normal olefin conversion rate is 95%, the yield is 82% (the water phase catalyst, the isomerization does not react. The longer the carbon chain is, the lower the activity of the olefin is, and the more difficult the reaction is), and the catalyst loss is 0.168% after 45 days of reaction.

[0062] Example 5

[0063] The raw material is C5-C7 component cut by rectification, the olefin content is 60% (of which the normal olefin is 42.7% and the isomerized olefin is 17.3%), the alkane content is 36%, the oxygen-containing compound is 1.9%, and the other (non-C5-C7 component such as C4 component) is 2.1%. The catalyst is rhodium and the ligand is triphenylphosphine, the raw material and the catalyst are added into the high-pressure reaction kettle with stirring, the mass ratio of the catalyst to the ligand is 1:5, and the catalyst concentration is 180 ppm. The kettle is purged with synthetic gas (CO:H2=1:1 (volume ratio)) for 5 times, the synthetic gas is continuously introduced to maintain the pressure in the kettle at 2 MP, the temperature is raised to 90°C, and the reaction time is 4 h. The reaction product enters the evaporator for separation, the first-stage evaporator operates at 50 KPa and the operating temperature is 50°C, the second-stage evaporator operates at 10 KPa and the operating temperature is 65°C, the gas chromatograph analysis shows that the olefin conversion rate is 89%, the normal olefin conversion rate is 99%, the yield is 53%, and the catalyst loss is 0.195% after 45 days of reaction. In this example, no solvent (toluene) is added, the role of the solvent is to dissolve the catalyst and to separate the raw material by boiling point, so that the separation is better. Without the solvent, the yield is low and the raw material and the catalyst are lost.

[0064] Example 6

[0065] The feedstock is C5-C7 fraction cut from distillation, with an olefin content of 60% (of which n-olefins are 42.7% and iso-olefins are 17.3%), an alkane content of 36%, oxygen-containing compounds of 1.9%, and other (non-C5-C7 components such as C4 components) of 2.1%. The catalyst is rhodium with triphenylphosphine as ligand, and the solvent is toluene, which is added to a high-pressure reaction kettle with stirring in a volume ratio of 1:1 with the deoxygenated Fischer-Tropsch oil feedstock, with the mass ratio of catalyst to ligand being 1:5, and the catalyst concentration being 180 ppm. The kettle is purged with synthetic gas (CO:H2=1:1 (volume ratio)) 5 times, and the synthetic gas is continuously fed while maintaining the pressure in the kettle at 2 MPa, and the temperature is raised to 90°C, and the reaction is carried out for 5 h. The reaction product is separated in an evaporator, with the first-stage evaporator operating at 50 KPa and an operating temperature of 60°C, and the second-stage evaporator operating at 10 KPa and an operating temperature of 75°C. The catalyst and the feedstock are continuously fed, and the operation is continuous. The operating results are shown in Table 1.

[0066] Table 1

[0067]

[0068] Example 7

[0069] The reaction is the same as in Example 1, except that the first-stage evaporator operates at normal pressure and an operating temperature of 50°C, and the second-stage evaporator operates at 10 KPa and an operating temperature of 110°C. Analysis shows that the olefin conversion is 75%, the n-olefin conversion is 99.2%, the yield is 82%, and the catalyst loss is 0.474% after 45 days of reaction. In this example, the evaporation rate is fast and the yield is high because of the high evaporation temperature of the first-stage and second-stage evaporators, but the amount of catalyst loss is also large.

[0070] Example 8

[0071] The reaction is the same as in Example 1, except that the first-stage evaporator operates at normal pressure and an operating temperature of 90°C, and the second-stage evaporator operates at 5 KPa and an operating temperature of 110°C. Analysis shows that the olefin conversion is 78%, the n-olefin conversion is 98.2%, the yield is 88%, and the catalyst loss is 1.387% after 45 days of reaction. In this example, the evaporation rate is fast and the yield is high because of the high evaporation temperature of the first-stage and second-stage evaporators, but the amount of catalyst loss is also large.

[0072] Example 9

[0073] The reaction is the same as example 1, the difference is that the first evaporator is operated at 50 KPa pressure, the operating temperature is 40℃, the second evaporator is operated at 5 KPa pressure, the operating temperature is 50℃. The analysis shows that the olefin conversion is 74%, the n-olefin conversion is 97.8%, the yield is 77%, the catalyst loss is 0.294% when the reaction is 45 days. In this example, the vacuum pressure is reduced, the actual temperature is higher than that of example 1, the evaporation rate is fast, the yield is higher, and the catalyst loss is larger.

[0074] From the above description, it can be seen that the above-mentioned embodiments of the present application achieve the following technical effects: in the above-mentioned method, under the catalysis of the catalyst, the olefin raw material and the synthesis gas undergo hydroformylation reaction to produce a reaction product containing aldehyde compounds; the reaction product is then separated, and the recovery of the catalyst is realized in the technology for recovering the aldehyde compounds, thereby reducing the loss of the catalyst in the hydroformylation reaction. The above-mentioned method can recover the catalyst in both homogeneous and heterogeneous reactions, realize the recycling of the catalyst, and reduce the loss of the catalyst. And for homogeneous reaction, by using evaporation to separate aldehyde compounds and catalyst, and further by setting two-stage evaporation and controlling the evaporation conditions, the catalyst can be ensured not to be in high-temperature environment for a long time, thereby preventing the catalyst from denaturation and deactivation due to high temperature, and further reducing the loss of the catalyst.

[0075] The above only describes the preferred embodiments of the present application and is not used to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for continuously producing an aldehyde compound by a hydroformylation reaction, characterized by, The method comprises: carrying out the hydroformylation reaction on an olefin raw material and synthesis gas with a catalyst to obtain a reaction product containing the aldehyde compound, separating the reaction product to obtain the aldehyde compound and recycling the catalyst at the same time; the hydroformylation reaction is a homogeneous reaction; the separation comprises: carrying out first evaporation on the reaction product to separate unreacted olefin from the reaction product to obtain a mixture of the aldehyde compound and the catalyst; and then carrying out second evaporation on the mixture of the aldehyde compound and the catalyst to obtain the aldehyde compound and the catalyst respectively; the evaporation comprises wiped film evaporation, the first evaporation comprises first wiped film evaporation, and the second evaporation comprises second wiped film evaporation; the temperature of the first wiped film evaporation is 40-80℃, and the pressure of the first wiped film evaporation is 5-101.325kPa; the temperature of the second wiped film evaporation is 50-100℃, and the pressure of the second wiped film evaporation is 10-20kPa; the aldehyde compound obtained by the homogeneous reaction has a carbon number of C5-C10; the hydroformylation reaction occurs in a solvent, and the solvent comprises one or more of toluene, PEG, DOP or water.

2. The method of claim 1, wherein, The evaporation area of the first wiped film evaporation and / or the second wiped film evaporation is 0.1-1 m 2 .

3. The method of claim 1, wherein, The feeding amount of the first wiped film evaporation and / or the second wiped film evaporation is 300-500mL / h.

4. The method of claim 1, wherein, The rotation speed of the first wiped film evaporation and / or the second wiped film evaporation is 100-300r / min.

5. The method of claim 1, wherein, The residence time of the first wiped film evaporation and / or the second wiped film evaporation is 20-40s.

6. The method of claim 1, wherein, The synthesis gas is CO and H2.

7. The method of claim 1, wherein, The catalyst comprises a combined catalyst comprising a complex of a metal and an organic phosphorus ligand.

8. The method of claim 7, wherein, The metal comprises rhodium.

9. The method of claim 7, wherein, The organic phosphorus ligand comprises a single phosphorus ligand or a double phosphorus ligand.

10. The method of claim 1, wherein, The concentration of the catalyst is 100-300ppm.

11. The method of claim 1, wherein, The pressure of the hydroformylation reaction is 5-50kPa.

12. The method of claim 1, wherein, The temperature of the hydroformylation reaction is 80-110℃.

13. The method of claim 1, wherein, The time of the hydroformylation reaction is 0.5-24h.

14. The method of claim 1, wherein, The olefin raw material comprises a Fischer-Tropsch synthesis oil raw material; the Fischer-Tropsch synthesis oil raw material is a fraction with a distillation range of C5-C20.

15. The method of claim 14, wherein, The Fischer-Tropsch synthesis oil raw material comprises, in terms of mass fraction, 25-40% alkanes, 35-60% normal olefins, 1-25% isomeric olefins and 0.1-2% oxygen-containing compounds.

16. The method of claim 14, wherein, The volume ratio of the Fischer-Tropsch synthesis oil raw material to the solvent is 1:1-2.

17. A process for the preparation of a higher alcohols, characterized by, The preparation method comprises: obtaining the aldehyde compound by the method for continuously preparing an aldehyde compound by the hydroformylation reaction according to any one of claims 1-16, then sequentially carrying out hydrogenation and purification on the aldehyde compound to obtain the higher alcohol.

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