Liquid-phase hydrogenation method and device for butyraldehyde, valeraldehyde and 2-propyl heptanal

Abstract

The invention relates to the technical field of alcohol preparation through aldehyde hydrogenation, in particular to a butyraldehyde, valeraldehyde and 2-propyl heptanal liquid-phase hydrogenation method and device, the device comprises a liquid-phase hydrogenation reactor, butyraldehyde, valeraldehyde and PBA, the liquid-phase hydrogenation reactor comprises an inner core pipe filled with a hydrogenation catalyst and an outer annular bed, and the outer annular bed is filled with a hydrogenation catalyst. The method is characterized in that butyraldehyde, valeraldehyde and PBA generated by an aldehyde-aldehyde condensation reaction are respectively fed into a hydrogenation system, the reactions of generating 2-propyl heptanol through PBA hydrogenation, generating butanol through butyraldehyde hydrogenation and generating pentanol through valeraldehyde hydrogenation are carried out in a liquid phase, and the pressure is about 2.4 MPa. Compared with gas-phase hydrogenation in the prior art, the liquid-phase hydrogenation adopted in the method has the advantages that the energy consumption is lower; the problem of high energy consumption of gas phase hydrogenation is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of preparing alcohol by hydrogenating aldehyde, in particular to a liquid phase hydrogenation method and device of butyl aldehyde, pentyl aldehyde and 2-propyl heptyl alcohol. BACKGROUND

[0002] Butanol, isooctanol and 2-propyl heptyl alcohol are important solvents and organic chemical raw materials, mainly used for preparing plasticizers of phthalate esters, aliphatic dibasic acid esters and phosphate esters, and widely used in various plastic and rubber products, and also used as extractants of oil, medicine and perfume and additives of alkyd resin coating. At present, the production process technology introduced in China is developed by Davy / DOW, which firstly generates aldehyde by carbonyl reaction of olefin and CO and H2 under the catalysis of rhodium / triphenyl phosphine catalyst system, and the aldehyde hydrogenation reaction process is one of the key processes for producing butanol, octanol and 2-propyl heptyl alcohol, and determines the quality of butanol and octanol and the economy of butyl octanol device. At present, most of the devices introduced in China adopt copper-zinc-based catalyst gas phase hydrogenation method, and the hydrogenation process equipment adopts fixed bed tube reactor, the reaction pressure is low (0.4-0.7 MPa), and the reaction temperature is high.

[0003] The existing hydrogenation catalysis method has the following defects: The gas phase aldehyde hydrogenation is an upflow gas phase reaction, the heat release is significant, the local hot spot is high, and the catalyst needs to have good mechanical strength and heat resistance.

[0004] The butyl aldehyde, pentyl aldehyde, 2-ethylhexyl alcohol and 2-propyl heptyl alcohol cooled by the previous system are vaporized and then hydrogenated, and the alcohol conversion is completed after cooling and separated from the circulating gas, the whole process has high energy consumption, has cold and hot diseases, and the use of circulating gas compressor for recycling of unreacted hydrogen causes high power consumption. SUMMARY

[0005] The present application aims to provide a liquid phase hydrogenation method and device of butyl aldehyde, pentyl aldehyde and 2-propyl heptyl alcohol to solve the problems in the background art.

[0006] To achieve the above-mentioned purpose, the present application provides the following technical scheme: A liquid phase hydrogenation method of butyl aldehyde, pentyl aldehyde and 2-propyl heptyl alcohol, comprising a liquid phase hydrogenation reactor, butyl aldehyde, pentyl aldehyde and PBA, the liquid phase hydrogenation reactor comprising an internal core tube filled with hydrogenation catalyst and an external annular bed, characterized in that: butyl aldehyde, pentyl aldehyde and PBA generated by aldehyde condensation reaction are respectively sent into the hydrogenation system, PBA is hydrogenated to generate 2-propyl heptyl alcohol, butyl aldehyde is hydrogenated to generate butanol, and pentyl aldehyde is hydrogenated to generate pentanol; The hydrogen, PBA, butyraldehyde, pentanal and the circulating hydrogen fluid are sent into the top of the annular bed together, and the reaction generates 2-propyl heptyl alcohol and butanol, 2-propyl 4-methyl 2-hexenal (Iso-PBA) and hydrogen generate byproduct 4-methyl 2-propyl hexanol by exothermic reaction, n-butyraldehyde and isobutyraldehyde generate n-butanol and isobutanol respectively, and pentanal generates pentanol respectively, in addition, the liquid phase hydrogenation reaction is added with a catalyst.

[0007] Further, the reaction of butyraldehyde, pentanal and PBA is carried out in a liquid phase, and the pressure is about 2.4 MPa Further, the catalyst comprises nickel, copper and alumina, and the content of the nickel is 30-60% by mass percentage of the hydrogenation catalyst, the content of the copper is 3-10%, and the content of the alumina is 30-60%.

[0008] Further, the unreacted hydrogen in the liquid phase hydrogenation reactor enters the liquid phase hydrogenation tail gas cooler.

[0009] Further, the fluid at the bottom of the annular bed is circulated by a liquid phase hydrogenation circulating pump.

[0010] Further, the liquid phase hydrogenation circulating cooler is used to remove the reaction heat, and the outlet temperature of the liquid phase hydrogenation circulating cooler is controlled by establishing a bypass system, so that the temperature rise of the material passing through the converter is 10-20 ℃.

[0011] Further, the liquid phase hydrogenation circulating cooler is used to generate low-pressure steam, so that the maximum temperature of the initial working condition of the liquid phase hydrogenation reactor is maintained at 165 ℃, and the maximum temperature of the final working condition is maintained at 175 ℃. A part of the circulating material and hydrogen are sent into the central pipe together to carry out primary conversion.

[0012] Further, the products generated in the central pipe are separated in the liquid collecting pan of the liquid phase hydrogenation reactor through a baffle, and the crude 2-propyl heptyl alcohol and the crude butanol flow out of the converter, all the alcohol products recovered from the liquid phase hydrogenation tail gas cooler are returned to the liquid collecting pan of the liquid phase hydrogenation reactor, and the mixed alcohol fluid passes through a crude alcohol filter to remove catalyst particles.

[0013] The liquid phase hydrogenation device for butyraldehyde, pentanal and 2-propyl heptyl aldehyde in the application is a liquid phase hydrogenation reactor.

[0014] Compared with the prior art, the application has the following beneficial effects: The butyraldehyde, pentanal and 2-propyl heptanal liquid phase hydrogenation method and device, the liquid phase hydrogenation is adopted in the application, compared with the gas phase hydrogenation in the prior art, the energy consumption is lower, the technical problems that the gas phase hydrogenation has high energy consumption, the material to be hydrogenated needs to be vaporized, the product after hydrogenation needs to be cooled, and the consumption of refrigerated water is high are solved. DETAILED DESCRIPTION

[0015] The technical solutions in the embodiments of the application will be clearly and completely described below. Obviously, the described embodiments are only part of the embodiments of the application, rather than all the embodiments of the application. Based on the embodiments in the application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the application.

[0016] The application provides a technical solution: A butyraldehyde, pentanal and 2-propyl heptanal liquid phase hydrogenation method, comprising a liquid phase hydrogenation reactor, butyraldehyde, pentanal, PBA, the liquid phase hydrogenation reactor comprising an internal core pipe filled with hydrogenation catalyst and an external annular bed, characterized in that: butyraldehyde, pentanal and PBA generated by aldol condensation reaction are respectively sent into a hydrogenation system, PBA is hydrogenated to generate 2-propyl heptanol, butyraldehyde is hydrogenated to generate butanol, and pentanal is hydrogenated to generate pentanol. Hydrogen, PBA, butyraldehyde, pentanal and a circulating hydrogenation fluid are sent into the top of the annular bed together, 2-propyl heptanol and butanol are generated by reaction, 4-methyl 2-propyl hexenal (Iso-PBA) and hydrogen generate byproduct 4-methyl 2-propyl hexanol by exothermic reaction, n-butyraldehyde and iso-butyraldehyde generate n-butanol and iso-butanol respectively, and pentanal generates pentanol, in addition, a catalyst is added during the liquid phase hydrogenation reaction.

[0017] Further, the catalyst comprises nickel, copper and alumina, the content of the nickel is 30-60% by mass percentage of the hydrogenation catalyst, the content of the copper is 3-10%, and the content of the alumina is 30-60%.

[0018] Further, the unreacted hydrogen in the liquid phase hydrogenation reactor enters a liquid phase hydrogenation tail gas cooler.

[0019] Further, the fluid at the bottom of the annular bed is circulated by a liquid phase hydrogenation circulating pump.

[0020] Further, a liquid phase hydrogenation circulating cooler is used to remove reaction heat, and the outlet temperature of the liquid phase hydrogenation circulating cooler is controlled by establishing a bypass system, so that the temperature rise of the material passing through the converter is 10-20 DEG C.

[0021] Further, the liquid phase hydrogenation circulating cooler is used to produce low pressure steam, so that the maximum temperature of the initial working condition of the liquid phase hydrogenation reactor is kept at 165℃, and the maximum temperature of the final working condition is kept at 175℃. A part of the circulating material is separated and sent into the central pipe together with hydrogen for primary conversion.

[0022] Further, the product produced in the central pipe is separated in the liquid phase hydrogenation reactor sump through a baffle, the crude 2-propyl heptanol and the crude butanol flow out of the converter, all the alcohol products recovered from the liquid phase hydrogenation tail gas cooler are returned to the liquid phase hydrogenation reactor sump, and the mixed alcohol fluid passes through a crude alcohol filter to remove catalyst particles.

[0023] The butyraldehyde, pentanal and 2-propyl heptanal liquid phase hydrogenation device in the application is a liquid phase hydrogenation reactor.

Claims

1. A method for liquid phase hydrogenation of butyraldehyde, pentanal, 2-propylheptanal, comprising a liquid phase hydrogenation reactor, butyraldehyde, pentanal, PBA, the liquid phase hydrogenation reactor comprising an inner core tube and an outer annular bed filled with hydrogenation catalyst, characterized in that: The butyraldehyde, pentanal and PBA produced by the aldol condensation reaction are fed into the hydrogenation system, the PBA is hydrogenated to produce 2-propyl heptanol, the butyraldehyde is hydrogenated to produce butanol, and the pentanal is hydrogenated to produce pentanol; The hydrogen, PBA, butyraldehyde, pentanal and the circulating hydrogenation fluid are fed into the top of the annular bed, and the reaction produces 2-propyl heptanol and butanol, 2-propyl 4-methyl 2-hexenal (Iso-PBA) and hydrogen are reacted exothermically to produce the byproduct 4-methyl 2-propyl hexanol, n-butyraldehyde and iso-butyraldehyde are respectively converted into n-butanol and iso-butanol, and pentanal is converted into pentanol, in addition, a catalyst is added during the liquid phase hydrogenation reaction.

2. The method according to claim 1, wherein the butyraldehyde, amylaldehyde, 2-propylheptanal liquid phase hydrogenation method is characterized by: The catalyst comprises nickel, copper and alumina, the content of the nickel is 30-60% by mass percentage of the hydrogenation catalyst, the content of the copper is 3-10%, and the content of the alumina is 30-60%.

3. The method according to claim 2, wherein the butyraldehyde, amylaldehyde, 2-propylheptanal liquid phase hydrogenation method is characterized by: The reaction of the butyraldehyde, pentanal and PBA is carried out in a liquid phase, and the pressure is about 2.4 MPa.

4. The method according to claim 3, wherein the butyraldehyde, amylaldehyde, 2-propylheptanal liquid phase hydrogenation method is characterized by: The unreacted hydrogen in the liquid phase hydrogenation reactor enters the liquid phase hydrogenation tail gas cooler.

5. The method according to claim 4, wherein the liquid phase hydrogenation of butyraldehyde, amylaldehyde, 2-propylheptanal is characterized by: The fluid at the bottom of the annular bed is circulated by a liquid phase hydrogenation circulating pump.

6. The method according to claim 5, wherein the butyraldehyde, amylaldehyde, 2-propylheptanal liquid phase hydrogenation method is characterized by: The liquid phase hydrogenation circulating cooler is used to remove the reaction heat, and the outlet temperature of the liquid phase hydrogenation circulating cooler is controlled by establishing a bypass system, so that the temperature rise of the material passing through the converter is 10-20℃.

7. The method according to claim 6, wherein the liquid phase hydrogenation of butyraldehyde, amylaldehyde, 2-propylheptanal is characterized by: The liquid phase hydrogenation circulating cooler is used to produce low-pressure steam, so that the maximum temperature of the initial working condition of the liquid phase hydrogenation reactor is maintained at 165℃, and the maximum temperature of the final working condition is maintained at 175℃. A part of the circulating fluid and hydrogen are fed into the center tube together to carry out a conversion.

8. The method according to claim 7, wherein the butyraldehyde, amylaldehyde, 2-propylheptanal liquid phase hydrogenation method is characterized by: The products produced in the center tube are separated in the liquid phase hydrogenation reactor sump through a baffle, crude 2-propyl heptanol and crude butanol flow out of the converter, all the alcohol products recovered from the liquid phase hydrogenation tail gas cooler are returned to the liquid phase hydrogenation reactor sump, and the mixed alcohol fluid passes through a crude alcohol filter to remove catalyst particles. The liquid phase hydrogenation circulating cooler is used to remove the reaction heat, and the outlet temperature of the liquid phase hydrogenation circulating cooler is controlled by establishing a bypass system, so that the temperature rise of the material passing through the converter is 10-20℃. The liquid phase hydrogenation circulating cooler is used to produce low-pressure steam, so that the maximum temperature of the initial working condition of the liquid phase hydrogenation reactor is maintained at 165℃, and the maximum temperature of the final working condition is maintained at 175℃. A part of the circulating fluid and hydrogen are fed into the center tube together to carry out a conversion. The products produced in the center tube are separated in the liquid phase hydrogenation reactor sump through a baffle, crude 2-propyl heptanol and crude butanol flow out of the converter, all the alcohol products recovered from the liquid phase hydrogenation tail gas cooler are returned to the liquid phase hydrogenation reactor sump, and the mixed alcohol fluid passes through a crude alcohol filter to remove catalyst particles.