Reaction device and method for producing succinic anhydride and co-producing butyrolactone and butanediol

Abstract

The invention provides a reaction device and method for producing succinic anhydride and co-producing butyrolactone and butanediol. The reaction device comprises an oxidation reaction device, a three-section type tube nest reaction device and a post-treatment device, and the oxidation reaction device obtains a solution rich in maleic anhydride. The three-section tubular reactor comprises a first-section tubular reactor, a second-section tubular reactor and a third-section tubular reactor which are respectively independent, and is used for respectively and simultaneously carrying out hydrogenation reduction reaction on the maleic anhydride-rich solution to respectively obtain butanedioic anhydride, butyrolactone and butanediol. The reaction device can solve the problems that in the prior art, a maleic anhydride catalytic hydrogenation reaction preparation method is complex in technological process, high in energy consumption, high in equipment investment cost, single in obtained hydrogenation product and low in yield.

Description

Technical Field

[0001] The invention belongs to the technical field of producing succinic anhydride by using n-butane, and in particular relates to a reaction device and method for producing succinic anhydride and co-producing butyrolactone and butanediol. Background Art

[0002] Maleic anhydride (maleic anhydride for short), also known as maleic anhydride, is an important fine chemical product and organic chemical raw material. It is the third largest organic anhydride in the world after acetic anhydride and phthalic anhydride. It is used in the production of unsaturated polyester resins, alkyd resins, pesticides, medicines, coatings, inks, lubricant additives and other fields. It can be used to produce a series of fine chemical products with a wide range of uses, and its development and utilization prospects are very broad.

[0003] At present, the industrial methods for producing maleic anhydride can be divided into four types according to the source of raw materials: benzene oxidation method, n-butane oxidation method, C 4 Olefin method and phthalic anhydride by-product method. The benzene oxidation method began in the 1920s. Its reaction mechanism, equipment development, catalyst design and other technologies are relatively mature. So far, some international and domestic companies still use this process. However, with the rise in the price of raw material benzene, increasingly stringent environmental protection requirements, and the development of green economic processes, this process has gradually lost its advantages. In the 1960s, n-butane was used as a cheap and environmentally friendly raw material for the preparation of maleic anhydride. This process quickly occupied the market with its wide source of raw materials and environmentally friendly production process. By the 1980s, this method had been widely used to replace the original benzene oxidation method internationally; C 4 The olefin method generates by-products such as acrylic acid, acetic acid, and acetaldehyde during the reaction process, and its development prospects are not optimistic; the phthalic anhydride by-product method is to separate and purify maleic anhydride from the by-product when producing phthalic anhydride from o-xylene, and the output is relatively low (about 5% of phthalic anhydride); and with the development of the petrochemical industry, its by-product C 4 The total amount is increasing year by year, and there are a large number of n-butane resources. Therefore, the n-butane oxidation method for preparing maleic anhydride has a wide range of raw material sources, less environmental pollution, low cost, and high atomic utilization rate compared to the benzene oxidation method, and has broad development prospects.

[0004] At present, the main synthesis method of maleic anhydride hydrogenation products is catalytic hydrogenation, and the main products obtained are: succinic anhydride, succinic acid, γ-butyrolactone, 1,4-butanediol and tetrahydrofuran, which have the characteristics of high product selectivity and high yield. However, a large amount of heat will be released during the catalytic hydrogenation reaction of maleic anhydride, especially in fixed bed reactors, to prevent the occurrence of catalyst coking deactivation and reaction raw material coking blockage caused by high temperature in the reactor.

[0005] Patent CN112608291A discloses a method for producing maleic anhydride by oxidative aqueous catalytic hydrogenation and co-production of succinic acid. The process uses benzene and air as raw materials, and an oxidation reaction is carried out under the action of a catalyst. The reaction gas is cooled by a partial condenser, and the resulting gas-liquid mixture is absorbed by water to generate acid water. Alternatively, the resulting gas-liquid mixture is further processed according to the following method to separate or not separate crude maleic anhydride. The uncondensed reaction gas or the unseparated gas-liquid mixture is absorbed by water or solvent, and further dehydrated or desorbed to produce crude maleic anhydride. After the crude maleic anhydride is refined and purified, it is sent to the condensation molding packaging process or the maleic anhydride production process for liquid external supply. In the subsequent aqueous catalytic hydrogenation of maleic anhydride to produce succinic acid, acid water and hydrogen are used as raw materials. After catalytic hydrogenation under the action of a catalyst, an aqueous solution of succinic acid or an aqueous solution of crude succinic acid is obtained. The aqueous solution of succinic acid is cooled, crystallized, and dried to obtain a succinic acid product; the aqueous solution of crude succinic acid is distilled or crystallized, dried, hydrolyzed, crystallized, and dried to obtain the product succinic acid. This process uses water as the absorption solvent. Due to the low boiling point of water, the water recovery process needs to adopt the distillation method, which consumes a lot of energy. In addition, the presence of acid water in the reaction process will corrode the pipeline equipment, shorten the service life of the equipment, and place high requirements on the equipment material, which increases the investment and operation costs.

[0006] Patent CN115536513A discloses a system for producing succinic acid by oxidation of n-butane or benzene. The present invention combines the two processes of maleic anhydride device and succinic acid, hydrogenates the rich absorption liquid absorbed by the solvent after catalytic oxidation of n-butane or benzene, generates succinic anhydride, and then strips to obtain succinic anhydride and solvent respectively. The solvent circulates to absorb the reaction gas rich in maleic anhydride and the hydrogenation reactor, and the succinic anhydride is hydrolyzed to obtain succinic acid. The process uses a stripping tower to recycle the solvent, and the heat energy is not fully utilized, resulting in a certain amount of steam waste, while also increasing the circulating water heat load. In addition, the process can only obtain one hydrogenation product, succinic acid, and the product is relatively single.

[0007] From the above analysis, it can be seen that the existing process for preparing maleic anhydride by catalytic hydrogenation reaction has the problems of complex process flow, high energy consumption, high equipment investment cost, single hydrogenation product and low yield. Summary of the invention

[0008] The main purpose of the present invention is to provide a reaction device and method for producing succinic anhydride and butyrolactone and butanediol, so as to solve the problems of the catalytic hydrogenation reaction preparation method of maleic anhydride in the prior art, such as complex process flow, high energy consumption, high equipment investment cost, single hydrogenation product and low yield.

[0009] In order to achieve the above-mentioned purpose, according to one aspect of the present invention, a reaction device for producing succinic anhydride and butyrolactone and butanediol is provided, the reaction device comprising: an oxidation reaction device having a raw material inlet and a product outlet, wherein the raw material inlet is respectively connected to an air source and an n-butane source, and is used for performing an oxidation reaction on n-butane and air to obtain a maleic anhydride-rich solution; a three-stage tubular reactor device comprising a first tubular reactor, a second tubular reactor and a third tubular reactor, each of which independently has an inlet and an outlet, and the inlets are respectively connected to the product outlet of the oxidation reaction device, and are used for performing a hydrogenation reduction reaction on the maleic anhydride-rich solution to obtain succinic anhydride, butyrolactone and butanediol respectively; and a post-processing device having a plurality of liquid inlets and a plurality of liquid outlets, wherein the plurality of liquid inlets are respectively connected to the outlets of the first tubular reactor, the second tubular reactor and the third tubular reactor, and the post-processing device comprises three groups of separators, and the three groups of separators are respectively used for post-processing succinic anhydride, butyrolactone and butanediol.

[0010] Furthermore, the three-stage tube-in-tube reaction equipment has a plurality of tubes perpendicular to the horizontal direction, and the tubes are filled with hydrogenation catalysts. In the horizontal direction, the three-stage tube-in-tube reaction equipment is divided into a first-stage tube-in-tube reactor, a second-stage tube-in-tube reactor and a third-stage tube-in-tube reactor, each of which is independent.

[0011] Furthermore, the bottom of the tubes of the first-stage tube reactor, the second-stage tube reactor and the third-stage tube reactor are independently provided with a bottom inlet, and a liquid inlet pipe is provided on the pipeline of the oxidation reaction equipment and the three-stage tube reactor. The liquid inlet pipe has multiple outlets, and the outlets of the liquid inlet pipe are respectively connected to the bottom inlets of the tubes in a one-to-one correspondence, so as to transport the maleic anhydride-rich solution into the tubes respectively.

[0012] Furthermore, the tops of the tubes of the first tube reactor, the second tube reactor and the third tube reactor are independently provided with a plurality of top inlets, and the top inlets are independently connected to a hydrogen source for conveying hydrogen into the tubes respectively.

[0013] Furthermore, the above three groups of separators include a first group of separators, a second group of separators and a third group of separators, and each group of separators independently includes a gas-liquid separation tank and a distillation tower connected in series, and the gas-liquid separation tanks are respectively connected to the outlets of the first section of the tube reactor, the second section of the tube reactor and the third section of the tube reactor in a one-to-one correspondence.

[0014] Furthermore, a condenser and a separation tower are sequentially arranged on the pipeline connecting the above-mentioned oxidation reaction equipment and the three-stage tube-in-tube reaction equipment.

[0015] According to another aspect of the present invention, there is provided a method for producing succinic anhydride and butyrolactone and butanediol by using the above-mentioned reaction device, the method comprising: step S1, performing an oxidation reaction of n-butane with air to obtain a maleic anhydride-rich solution; step S2, performing a first hydrogenation reduction reaction on a portion of the maleic anhydride-rich solution to obtain a first hydrogenation system; performing a second hydrogenation reduction reaction on another portion of the maleic anhydride-rich solution to obtain a second hydrogenation system; performing a third hydrogenation reduction reaction on the remaining maleic anhydride-rich solution to obtain a third hydrogenation system; and step S3, performing a first separation treatment on the first hydrogenation system in sequence to obtain butanediol; performing a second separation treatment on the second hydrogenation system in sequence to obtain butyrolactone; and performing a third separation treatment on the third hydrogenation system in sequence to obtain succinic anhydride.

[0016] Furthermore, the conditions of the first hydrogenation reduction reaction are: a temperature of 250 to 300° C., and / or an absolute pressure of 0.5 to 5 MPa, and / or a mass space velocity of 0.1 to 3 h -1 The conditions for the second hydrogenation reduction reaction are preferably: a temperature of 180 to 220°C, and / or an absolute pressure of 0.5 to 5 MPa, and / or a mass space velocity of 0.1 to 3 h -1 The conditions for the third hydrogenation reduction reaction are preferably: a temperature of 150 to 175°C, and / or an absolute pressure of 0.5 to 5 MPa, and / or a mass space velocity of 0.1 to 3 h -1 ; Preferably, the mass ratio of the maleic anhydride-rich solution in the first hydrogenation reduction reaction, the second hydrogenation reduction reaction, and the third hydrogenation reduction reaction is 0.5-4.5:0.5-4.5:5-9.

[0017] Further, the above step S3 includes: performing a first gas-liquid separation treatment on the first hydrogenation system to obtain a first separated gas and a first separated liquid; returning part of the first separated liquid to the system subjected to the first gas-liquid separation treatment, and performing a first rectification treatment on the remaining first separated liquid, preferably, the first separated liquid subjected to the first rectification treatment is 60 to 100% of the total mass of the first separated liquid; preferably, the conditions for the first rectification treatment are a vacuum degree of -80 KPa to -10 KPa and a temperature of 100°C to 200°C; and / or performing a second gas-liquid separation treatment on the second hydrogenation system to obtain a second separated gas and a second separated liquid; returning part of the second separated liquid to the system subjected to the first gas-liquid separation treatment, and performing a second rectification treatment on the remaining second separated liquid. Second distillation treatment, preferably the second separated liquid subjected to the second distillation treatment accounts for 50-80% of the total mass of the second separated liquid; preferably, the conditions for the second distillation treatment are a vacuum degree of -60KPa to -10KPa and a temperature of 100°C to 200°C; and / or the third hydrogenation system is subjected to a third gas-liquid separation treatment to obtain a third separated gas and a third separated liquid; a part of the third separated liquid is returned to the second gas-liquid separation treatment system, and the remaining third separated liquid is subjected to a third distillation treatment, preferably, the third separated liquid subjected to the third distillation treatment accounts for 50-90% of the total mass of the third separated liquid; preferably, the conditions for the third distillation treatment are a vacuum degree of -50KPa to -10KPa and a temperature of 100°C to 200°C.

[0018] Furthermore, the preparation process of the above-mentioned maleic anhydride-rich solution also includes: condensing and separating the system obtained by the oxidation reaction in sequence to obtain a maleic anhydride-rich solution; the catalyst used in the oxidation reaction is preferably a VPO catalyst; the temperature of the oxidation reaction is preferably 300-450°C, and the pressure of the oxidation reaction is preferably 0-3MPa.

[0019] By applying the technical solution of the present application, in the present invention, n-butane and air are first subjected to oxidation reaction in an oxidation reaction device to obtain a maleic anhydride-rich solution. Hydrogenation reduction reaction is synchronously carried out in the first tube reactor, the second tube reactor and the third tube reactor of the three-stage tube reactor device, and the hydrogenation products are respectively post-processed by post-processing equipment, and process parameters are separately controlled in each tube reactor. The process flow is simple and the operation is flexible, the reaction efficiency is high, and butyrolactone and butanediol can be co-produced on the basis of high-purity succinic anhydride, thereby solving the problems of high energy consumption, large investment and large number of reactors in the prior art, and having good economic benefits and industrial application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0021] Figure 1A schematic diagram of a reaction device for producing succinic anhydride and butyrolactone and butanediol provided in Example 1 of the present invention is shown.

[0022] Among them, the above drawings include the following reference numerals:

[0023] 1. Oxidation reaction equipment; 2. Three-stage tubular reaction equipment; 3. First-stage tubular reactor; 4. Second-stage tubular reactor; 5. Second-stage tubular reactor; 6. Post-processing equipment; 7. Gas-liquid separation tank; 8. Distillation tower; 9. Condenser; 10. Separation tower. DETAILED DESCRIPTION

[0024] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0025] As analyzed in the background technology of the present application, the preparation method of maleic anhydride by catalytic hydrogenation reaction in the prior art has the problems of complex process flow, high energy consumption, high equipment investment cost, single hydrogenation product and low yield. In order to solve this problem, the present application provides a reaction device and method for producing succinic anhydride and co-producing butyrolactone and butanediol.

[0026] In a typical embodiment of the present application, a reaction device for producing succinic anhydride and butyrolactone and butanediol is provided, such as Figure 1 As shown, the reaction device includes an oxidation reaction device 1, a three-stage tubular reactor 2 and a post-processing device 6, wherein the oxidation reaction device 1 has a raw material inlet and a product outlet, and the raw material inlet is connected to an air source and a n-butane source respectively, and is used to hydrogenate n-butane and air to obtain a maleic anhydride-rich solution; the three-stage tubular reactor 2 includes a first-stage tubular reactor 3, a second-stage tubular reactor 4 and a third-stage tubular reactor 5, each of which is independently The post-processing device 6 has an independent inlet and an outlet, and the inlet is connected to the product outlet of the oxidation reaction device 1, respectively, for simultaneously performing hydrogenation reduction reaction on the maleic anhydride-rich solution to obtain succinic anhydride, butyrolactone and butanediol, respectively; the post-processing device 6 has multiple liquid inlets and multiple liquid outlets, and the multiple liquid inlets are connected to the outlets of the first tube reactor 3, the second tube reactor 4 and the third tube reactor 5, respectively. The post-processing device 6 includes three groups of separators, and the three groups of separators are used to post-process succinic anhydride, butyrolactone and butanediol, respectively.

[0027] In the present invention, n-butane and air are first subjected to oxidation reaction in an oxidation reaction device 1 to obtain a maleic anhydride-rich solution. Hydrogenation reduction reaction is synchronously performed in the first tube reactor 3, the second tube reactor 4 and the third tube reactor 5 of the three-stage tube reactor 2, and the hydrogenation products are respectively post-processed by a post-processing device 6. The process parameters are individually controlled in each tube reactor. The process flow is simple and the operation is flexible. The reaction efficiency is high, and high-purity succinic anhydride can be obtained and butyrolactone and butanediol can be co-produced. Thus, the problems of high energy consumption, large investment and large number of reactors in the prior art are solved, and the invention has good economic benefits and industrial application prospects.

[0028] In addition, multiple temperature sensors and temperature control points are provided in the first tube reactor 3, the second tube reactor 4 and the third tube reactor 5 of the three-stage tube reactor equipment 2 to effectively control the temperature of the hydrogenation reduction reaction in each tube reactor.

[0029] In one embodiment of the present application, the three-stage tube-in-tube reaction equipment 2 has a plurality of tubes perpendicular to the horizontal direction, and the tubes are filled with hydrogenation catalysts. In the horizontal direction, the three-stage tube-in-tube reaction equipment is divided into a first-stage tube-in-tube reactor 3, a second-stage tube-in-tube reactor 4 and a third-stage tube-in-tube reactor 5, each of which is independent of the other.

[0030] The above vertical three-stage tube-in-tube reaction equipment is more helpful to improve the countercurrent contact effect between the maleic anhydride-rich solution and hydrogen.

[0031] In one embodiment of the present application, the bottom of the tubes of the first-stage tube reactor 3, the second-stage tube reactor 4 and the third-stage tube reactor 5 are independently provided with a bottom inlet, and a liquid inlet pipe is provided on the pipeline of the oxidation reaction equipment 1 and the three-stage tube reactor 2, and the liquid inlet pipe has multiple outlets, and the outlets of the liquid inlet pipe are respectively connected to the bottom inlets of the tubes one by one, so as to transport the maleic anhydride-rich solution into the tubes respectively.

[0032] The outlets of the above liquid inlet pipes are connected to the bottom inlets of the tubes one by one, so that the maleic anhydride-rich solution can continuously enter the tubes as a raw material for hydrogenation reduction reaction, thereby completing the feeding in different tubes.

[0033] In one embodiment of the present application, the tops of the tubes of the first-stage tube reactor 3, the second-stage tube reactor 4 and the third-stage tube reactor 5 independently have multiple top inlets, and the top inlets are independently connected to a hydrogen source for transporting hydrogen into the tubes respectively.

[0034] Through the above settings, hydrogen is introduced into each tube from the top of each stage of the tubular reactor, thereby promoting the countercurrent contact between hydrogen and the maleic anhydride-rich solution introduced into each tube from the bottom of each stage of the tubular reactor, and then maximizing the efficiency and effect of each hydrogenation reduction reaction. In addition, by adjusting the pressure in each stage of the tubular reactor, large-scale production of the products of the maleic anhydride hydrogenation reaction is achieved.

[0035] In an embodiment of the present application, the above three groups of separators include a first group of separators, a second group of separators, and a third group of separators. Each group of separators independently includes a series-connected gas-liquid separation tank 7 and a rectifying column 8. The gas-liquid separation tank 7 is respectively connected in one-to-one correspondence with the outlets of the first-stage tubular reactor 3, the second-stage tubular reactor 4, and the third-stage tubular reactor 5.

[0036] The above equipment helps to continuously purify the first separation liquid, the second separation liquid, and the third separation liquid to obtain purer succinic anhydride, butyrolactone, and butanediol. In addition, condensers are provided on the pipelines connecting the three-stage tubular reaction equipment 2 to each gas-liquid separation tank, thereby helping to condense the first hydrogenation system, the second hydrogenation system, and the third hydrogenation system coming out of the three-stage tubular reaction equipment 2 respectively.

[0037] In an embodiment of the present application, a condenser and a separation tower are sequentially provided on the pipeline connecting the above oxidation reaction equipment and the three-stage tubular reaction equipment.

[0038] The preferred condenser 9 and separation tower 10 are beneficial to purify the system obtained from the oxidation reaction of n-butane and air, so as to obtain a maleic anhydride-rich solution with as high a purity as possible. In addition, in order to improve the mixing effect of n-butane and air and thus obtain a uniform reaction raw material gas, a static mixer is provided on the pipeline between the n-butane source (air source) and the oxidation reaction equipment 1. A liquid feed pump is provided on the pipeline connecting the separation tower 10 and the three-stage tubular reaction equipment 2 to respectively transport the maleic anhydride-rich solution to the first-stage tubular reactor 3, the second-stage tubular reactor 4, and the third-stage tubular reactor 5.

[0039] In another typical embodiment of the present application, a method for producing succinic anhydride and butyrolactone and butanediol by using the above-mentioned reaction device is provided, the method comprising: step S1, performing an oxidation reaction of n-butane with air to obtain a maleic anhydride-rich solution; step S2, performing a first hydrogenation reduction reaction on a portion of the maleic anhydride-rich solution to obtain a first hydrogenation system; performing a second hydrogenation reduction reaction on another portion of the maleic anhydride-rich solution to obtain a second hydrogenation system; performing a third hydrogenation reduction reaction on the remaining maleic anhydride-rich solution to obtain a third hydrogenation system; and step S3, performing a first separation treatment on the first hydrogenation system in sequence to obtain butanediol; performing a second separation treatment on the second hydrogenation system in sequence to obtain butyrolactone; and performing a third separation treatment on the third hydrogenation system in sequence to obtain succinic anhydride.

[0040] The above method of producing succinic anhydride and co-producing butyrolactone and butanediol in the present application benefits from the synchronous conduct of the three-stage hydrogenation reduction reaction, and the process parameters are separately controlled in each section of the tubular reactor. The process flow is simple and the operation is flexible, the reaction efficiency is high, and butyrolactone and butanediol can be co-produced on the basis of obtaining high-purity succinic anhydride, which has good economic benefits and industrial application prospects, thereby solving the problems of high energy consumption, large investment, large number of reactors, single hydrogenation product and low yield in the prior art. And the above method of the present application has mild reaction conditions, few equipment and devices, simple process flow, precise reaction, excellent reaction effect, high selectivity of the obtained succinic anhydride, and can co-produce butyrolactone and butanediol at the same time, thereby greatly reducing high energy consumption and reducing costs.

[0041] In addition, the catalysts for the first hydrogenation reduction reaction, the second hydrogenation reduction reaction and the third hydrogenation reduction reaction of the present invention can be the same. The present invention does not specifically specify the catalyst carrier for the catalytic hydrogenation reaction. The conventional catalytic hydrogenation reaction catalyst in the art can be used as the carrier to prepare the Ni and Cu-based catalyst by the impregnation method. In the specific embodiment of the present invention, the catalyst carrier can be preferably selected from ZSM-5, ZSM-11, Al 2 O 3 , MCM-41 and MCM-56 molecular sieves.

[0042] The catalyst for producing succinic acid and succinic anhydride by catalytic hydrogenation of maleic anhydride in a countercurrent tubular reactor may include the following steps: forming a molecular sieve carrier; further, at least one of alumina (such as pseudo-boehmite), SB powder, silica sol or kaolin can be used as a binder during forming; the formed molecular sieve carrier is dried and calcined; further, the drying temperature can be room temperature-200°C, and the drying time can be 2-24 hours; the calcination temperature can be 500-600°C, and the calcination time can be 3-8 hours; the preparation of Ni and Cu-based catalysts mainly adopts an impregnation method, using the above-mentioned self-made alumina-silicon oxide composite carrier, putting it into the corresponding solution of the required concentration, controlling the required temperature in a constant temperature water bath, and is constantly immersed in the prepared solution for 24 hours; the Ni and Cu-based catalysts are dried and calcined; further, the drying temperature can be room temperature-200°C, and the drying time can be 2-24 hours; the calcination temperature can be 500-600°C, and the calcination time can be 3-8 hours.

[0043] In one embodiment of the present application, the conditions of the first hydrogenation reduction reaction are: temperature of 250-300°C, and / or absolute pressure of 0.5-5 MPa, and / or mass space velocity of 0.1-3 h -1 The conditions for the second hydrogenation reduction reaction are preferably: a temperature of 180 to 220°C, and / or an absolute pressure of 0.5 to 5 MPa, and / or a mass space velocity of 0.1 to 3 h -1 The conditions for the third hydrogenation reduction reaction are preferably: a temperature of 150 to 175°C, and / or an absolute pressure of 0.5 to 5 MPa, and / or a mass space velocity of 0.1 to 3 h -1 ; Preferably, the mass ratio of the maleic anhydride-rich solution in the first hydrogenation reduction reaction, the second hydrogenation reduction reaction, and the third hydrogenation reduction reaction is 0.5-4.5:0.5-4.5:5-9.

[0044] By controlling the conditions of the first hydrogenation reduction reaction, the conditions of the second hydrogenation reduction reaction, and the conditions of the third hydrogenation reduction reaction to be within the above ranges, respectively, it is helpful to promote the first hydrogenation reduction reaction to obtain butanediol, promote the second hydrogenation reduction reaction to obtain butyrolactone, and promote the third hydrogenation reduction reaction to obtain succinic anhydride, thereby increasing the yield of butanediol, butyrolactone, and succinic anhydride as much as possible. Preferably, the mass ratio of the rich maleic anhydride solution in the first hydrogenation reduction reaction, the second hydrogenation reduction reaction, and the third hydrogenation reduction reaction is controlled within the above range, which helps to make the rich maleic anhydride solution better adapted to the conditions of the first hydrogenation reduction reaction, the second hydrogenation reduction reaction, and the third hydrogenation reduction reaction, thereby maximally converting the rich maleic anhydride solution into pure succinic anhydride, butyrolactone, and butanediol.

[0045] In one embodiment of the present application, the above-mentioned step S3 includes: performing a first gas-liquid separation treatment on the first hydrogenation system to obtain a first separated gas and a first separated liquid; returning part of the first separated liquid to the system subjected to the first gas-liquid separation treatment, and performing a first distillation treatment on the remaining first separated liquid, preferably, the first separated liquid subjected to the first distillation treatment is 60 to 100% of the total mass of the first separated liquid; preferably, the conditions for the first distillation treatment are a vacuum degree of -80KPa to -10KPa and a temperature of 100°C to 200°C; and / or performing a second gas-liquid separation treatment on the second hydrogenation system to obtain a second separated gas and a second separated liquid; returning part of the second separated liquid to the system subjected to the first gas-liquid separation treatment, and the remaining second separated liquid The liquid is subjected to a second distillation treatment, and the second separated liquid subjected to the second distillation treatment is preferably 50-80% of the total mass of the second separated liquid; the conditions for the second distillation treatment are preferably a vacuum degree of -60KPa to -10KPa and a temperature of 100°C to 200°C; and / or the third hydrogenation system is subjected to a third gas-liquid separation treatment to obtain a third separated gas and a third separated liquid; a part of the third separated liquid is returned to the second gas-liquid separation treatment system, and the remaining third separated liquid is subjected to a third distillation treatment, and the third separated liquid subjected to the third distillation treatment is preferably 50-90% of the total mass of the third separated liquid; the conditions for the third distillation treatment are preferably a vacuum degree of -50KPa to -10KPa and a temperature of 100°C to 200°C.

[0046] The conditions of the preferred first distillation treatment, the second distillation treatment and the third distillation treatment are within the above ranges, which helps to improve the efficiency and effect of each distillation treatment, thereby making the obtained succinic anhydride, butyrolactone and butanediol purer. It is preferred that part of the first separated liquid, part of the second separated liquid and part of the third separated liquid are returned to the gas-liquid separation treatment system for deep hydrogenation, which helps to improve the efficiency and effect of each gas-liquid separation and obtain as much valuable butyrolactone and butanediol as possible.

[0047] In one embodiment of the present application, the preparation process of the above-mentioned maleic anhydride-rich solution also includes: condensing and separating the system obtained by the oxidation reaction in sequence to obtain a maleic anhydride-rich solution; the catalyst used in the oxidation reaction is preferably a VPO catalyst; the temperature of the oxidation reaction is preferably 300-450°C, and the pressure of the oxidation reaction is preferably 0-3MPa.

[0048] The preferred temperature and pressure of the oxidation reaction are helpful to improve the efficiency and effect of the oxidation reaction. After condensation and separation, a maleic anhydride-rich solution as pure as possible is obtained, thereby laying a foundation for the reduction hydrogenation reaction of the maleic anhydride-rich solution.

[0049] The beneficial effects of the present application will be further illustrated below in conjunction with embodiments.

[0050] Example 1

[0051] according to Figure 1 The schematic diagram of the reaction device for producing succinic anhydride and butyrolactone and butanediol is shown. 30g of VPO catalyst is loaded into the oxidation reactor, the concentration of n-butane entering the oxidation reactor is 5%, the reaction pressure is 0.05MPa, and the reaction temperature is 350°C.

[0052] 30g of 5% Ni-ZSM-5 catalyst was loaded into a three-stage tubular reactor of a fixed bed hydrogenation reaction system. The maleic anhydride solution was divided into three routes and entered the lower part of each stage of the reactor. The mass ratio of the maleic anhydride solution in the first hydrogenation reduction reaction, the second hydrogenation reduction reaction, and the third hydrogenation reduction reaction was 0.5:0.5:9. The process conditions of the reaction were as follows: the temperature of the first hydrogenation reduction reaction was 250°C, the pressure was 1.0MPa, and WHSV=0.2h -1 The temperature of the second hydrogenation reduction reaction is 180°C, the pressure is 1.0 MPa, and WHSV = 0.5 h -1 The temperature of the third hydrogenation reduction reaction is 150°C, the pressure is 1.0 MPa, and WHSV = 1.0 h -1 .

[0053] The reaction product is discharged from the upper part of the three-stage tubular reactor of the fixed bed hydrogenation reaction system, and the first separated liquid, the second separated liquid and the third separated liquid are respectively discharged from the bottom of the gas-liquid separation tank, 60% of the total mass of the first separated liquid enters the first distillation treatment, and is distilled at a vacuum degree of -80 KPa and a temperature of 100°C, 50% of the total mass of the second separated liquid enters the second distillation treatment, and is distilled at a vacuum degree of -60 KPa and a temperature of 100°C, and 50% of the total mass of the third separated liquid enters the third distillation treatment, and is distilled at a vacuum degree of -50 KPa and a temperature of 100°C, to obtain n-butane to produce succinic anhydride and butyrolactone and butanediol: the yield of succinic anhydride is 97.5%, the yield of butyrolactone is 1.2%, and the yield of butanediol is 1.3%.

[0054] Example 2

[0055] 35 g of VPO catalyst was loaded into the oxidation reactor. The concentration of n-butane entering the oxidation reactor was 7%. The reaction pressure was 1 MPa and the reaction temperature was 400°C.

[0056] 30g of 5% Ni-ZSM-5 catalyst was loaded into a three-stage tubular reactor of a fixed bed hydrogenation reaction system. The maleic anhydride solution was divided into three routes and entered the lower part of each stage of the reactor. The mass ratio of the maleic anhydride solution in the first hydrogenation reduction reaction, the second hydrogenation reduction reaction, and the third hydrogenation reduction reaction was 0.5:1:8.5. The process conditions of the reaction were as follows: the temperature of the first hydrogenation reduction reaction was 270°C, the pressure was 1.0MPa, and WHSV=0.5h -1; The temperature of the second hydrogenation reduction reaction is 200°C, the pressure is 1.0MPa, and WHSV=0.5h -1 The temperature of the third hydrogenation reduction reaction is 155°C, the pressure is 1.0 MPa, and WHSV = 0.8 h -1 .

[0057] The reaction product is discharged from the upper part of the three-stage tubular reactor of the fixed bed hydrogenation reaction system, and the first separated liquid, the second separated liquid and the third separated liquid are respectively discharged from the bottom of the gas-liquid separation tank. 70% of the total mass of the first separated liquid enters the first distillation treatment and is distilled at a vacuum degree of -70 KPa and a temperature of 110°C. 60% of the total mass of the second separated liquid enters the second distillation treatment and is distilled at a vacuum degree of -50 KPa and a temperature of 110°C. 55% of the total mass of the third separated liquid enters the third distillation treatment and is distilled at a vacuum degree of -40 KPa and a temperature of 110°C to obtain n-butane to produce succinic anhydride and co-produce butyrolactone and butanediol: the yield of succinic anhydride is 90.0%, the yield of butyrolactone is 5.0%, and the yield of butanediol is 5.0%.

[0058] Example 3

[0059] 50 g of VPO catalyst was loaded into the oxidation reactor. The concentration of n-butane entering the oxidation reactor was 7%. The reaction pressure was 1 MPa and the reaction temperature was 400°C.

[0060] 50g of 10% Ni-ZSM-5 catalyst was loaded into a three-stage tubular reactor of a fixed bed hydrogenation reaction system. The maleic anhydride solution was divided into three routes and entered the lower part of each stage of the reactor. The mass ratio of the maleic anhydride solution in the first hydrogenation reduction reaction, the second hydrogenation reduction reaction, and the third hydrogenation reduction reaction was 1:1:8. The process conditions of the reaction were as follows: the temperature of the first hydrogenation reduction reaction was 270°C, the pressure was 2.0MPa, and WHSV=0.8h -1 ; The temperature of the second hydrogenation reduction reaction is 200°C, the pressure is 1.0MPa, and WHSV=0.8h -1 The temperature of the third hydrogenation reduction reaction is 160°C, the pressure is 1.5MPa, and WHSV=0.8h -1 .

[0061] The reaction product is discharged from the upper part of the three-stage tubular reactor of the fixed bed hydrogenation reaction system, and the first separated liquid, the second separated liquid and the third separated liquid are respectively discharged from the bottom of the gas-liquid separation tank. 75% of the total mass of the first separated liquid enters the first distillation treatment and is distilled at a vacuum degree of -65 KPa and a temperature of 120°C. 65% of the total mass of the second separated liquid enters the second distillation treatment and is distilled at a vacuum degree of -45 KPa and a temperature of 120°C. 60% of the total mass of the third separated liquid enters the third distillation treatment and is distilled at a vacuum degree of -35 KPa and a temperature of 110°C to obtain n-butane to produce succinic anhydride and butyrolactone and butanediol: the yield of succinic anhydride is 92%, the yield of butyrolactone is 7%, and the yield of butanediol is 1%.

[0062] Example 4

[0063] 50 g of VPO catalyst was loaded into the oxidation reactor. The concentration of n-butane entering the oxidation reactor was 10%. The reaction pressure was 1.5 MPa and the reaction temperature was 450°C.

[0064] 50g of 10% Ni-ZSM-11 catalyst was loaded into a three-stage tubular reactor of a fixed bed hydrogenation reaction system. The maleic anhydride solution was divided into three routes and entered the lower part of each stage of the reactor. The mass ratio of the maleic anhydride solution in the first hydrogenation reduction reaction, the second hydrogenation reduction reaction, and the third hydrogenation reduction reaction was 1:0.5:8.5. The process conditions of the reaction were as follows: the temperature of the first hydrogenation reduction reaction was 270°C, the pressure was 1.5MPa, and WHSV=0.8h -1 The temperature of the second hydrogenation reduction reaction is 200°C, the pressure is 1.3MPa, and WHSV=0.8h -1 The temperature of the third hydrogenation reduction reaction is 165°C, the pressure is 2MPa, and WHSV=0.8h -1 .

[0065] The reaction product is discharged from the upper part of the three-stage tubular reactor of the fixed bed hydrogenation reaction system, and the first separated liquid, the second separated liquid and the third separated liquid are respectively discharged from the bottom of the gas-liquid separation tank. 80% of the total mass of the first separated liquid enters the first distillation treatment and is distilled at a vacuum degree of -60 KPa and a temperature of 125°C. 70% of the total mass of the second separated liquid enters the second distillation treatment and is distilled at a vacuum degree of -40 KPa and a temperature of 125°C. 65% of the total mass of the third separated liquid enters the third distillation treatment and is distilled at a vacuum degree of -30 KPa and a temperature of 115°C to obtain n-butane to produce succinic anhydride and butyrolactone and butanediol: the yield of succinic anhydride is 95%, the yield of butyrolactone is 4.5%, and the yield of butanediol is 0.5%.

[0066] Example 5

[0067] 50 g of VPO catalyst was loaded into the oxidation reactor. The concentration of n-butane entering the oxidation reactor was 15%. The reaction pressure was normal pressure and the reaction temperature was 450°C.

[0068] 90g of 10% Ni-ZSM-11 catalyst was loaded into a three-stage tubular reactor of a fixed bed hydrogenation reaction system. The maleic anhydride solution was divided into three routes and entered the lower part of each stage of the reactor. The mass ratio of the maleic anhydride solution in the first hydrogenation reduction reaction, the second hydrogenation reduction reaction, and the third hydrogenation reduction reaction was 0.5:1.5:8. The process conditions of the reaction were as follows: the temperature of the first hydrogenation reduction reaction was 270°C, the pressure was 2MPa, and WHSV=0.5h -1 ; The temperature of the second hydrogenation reduction reaction is 200°C, the pressure is 2MPa, and WHSV=0.5h -1 The temperature of the third hydrogenation reduction reaction is 170°C, the pressure is 2MPa, and WHSV=0.8h -1 .

[0069] The reaction product is discharged from the upper part of the three-stage tubular reactor of the fixed bed hydrogenation reaction system, and the first separated liquid, the second separated liquid and the third separated liquid are respectively discharged from the bottom of the gas-liquid separation tank. 85% of the total mass of the first separated liquid enters the first distillation treatment and is distilled at a vacuum degree of -55 KPa and a temperature of 130°C. 75% of the total mass of the second separated liquid enters the second distillation treatment and is distilled at a vacuum degree of -35 KPa and a temperature of 130°C. 70% of the total mass of the third separated liquid enters the third distillation treatment and is distilled at a vacuum degree of -25 KPa and a temperature of 120°C to obtain n-butane to produce succinic anhydride and butyrolactone and butanediol: the yield of succinic anhydride is 98.2%, the yield of butyrolactone is 1.2%, and the yield of butanediol is 0.6%.

[0070] Example 6

[0071] 50 g of VPO catalyst was loaded into the oxidation reactor. The concentration of n-butane entering the oxidation reactor was 5%. The reaction pressure was 2.5 MPa and the reaction temperature was 300°C.

[0072] 90g of 5% Ni-MCM-41 catalyst was loaded into a three-stage tubular reactor of a fixed bed hydrogenation reaction system. The maleic anhydride solution was divided into three routes and entered the lower part of each stage of the reactor. The mass ratio of the maleic anhydride solution in the first hydrogenation reduction reaction, the second hydrogenation reduction reaction, and the third hydrogenation reduction reaction was 1.5:0.5:8. The process conditions of the reaction were as follows: the temperature of the first hydrogenation reduction reaction was 270°C, the pressure was 2MPa, and WHSV=1.5h -1 ; The temperature of the second hydrogenation reduction reaction is 200°C, the pressure is 2MPa, and WHSV=1.5h -1The temperature of the third hydrogenation reduction reaction is 170°C, the pressure is 2MPa, and WHSV=1h -1 .

[0073] The reaction product is discharged from the upper part of the three-stage tubular reactor of the fixed bed hydrogenation reaction system, and the first separated liquid, the second separated liquid and the third separated liquid are respectively discharged from the bottom of the gas-liquid separation tank. 90% of the total mass of the first separated liquid enters the first distillation treatment and is distilled at a vacuum degree of -50 KPa and a temperature of 140°C. 80% of the total mass of the second separated liquid enters the second distillation treatment and is distilled at a vacuum degree of -30 KPa and a temperature of 140°C. 75% of the total mass of the third separated liquid enters the third distillation treatment and is distilled at a vacuum degree of -20 KPa and a temperature of 130°C to obtain n-butane to produce succinic anhydride and butyrolactone and butanediol: the yield of succinic anhydride is 99.3%, the yield of butyrolactone is 0.2%, and the yield of butanediol is 0.5%.

[0074] Example 7

[0075] 90 g of VPO catalyst was loaded into the oxidation reactor. The concentration of n-butane entering the oxidation reactor was 5%, the reaction pressure was 2.5 MPa, and the reaction temperature was 300°C.

[0076] 50g of 10% Ni-MCM-41 catalyst was loaded into a three-stage tubular reactor of a fixed bed hydrogenation reaction system. The maleic anhydride solution was divided into three paths and entered the lower part of each stage of the reactor. The mass ratio of the maleic anhydride solution in the first hydrogenation reduction reaction, the second hydrogenation reduction reaction, and the third hydrogenation reduction reaction was 1.5:1:7.5. The process conditions of the reaction were as follows: the temperature of the first hydrogenation reduction reaction was 270°C, the pressure was 1MPa, and WHSV=1.5h -1 The temperature of the second hydrogenation reduction reaction is 200°C, the pressure is 1MPa, and WHSV=1.3h -1 The temperature of the third hydrogenation reduction reaction is 170°C, the pressure is 2MPa, and WHSV=1h -1 .

[0077] The reaction product is discharged from the upper part of the three-stage tubular reactor of the fixed bed hydrogenation reaction system, and the first separated liquid, the second separated liquid and the third separated liquid are respectively discharged from the bottom of the gas-liquid separation tank. 95% of the total mass of the first separated liquid enters the first distillation treatment and is distilled at a vacuum degree of -45KPa and a temperature of 150°C. 80% of the total mass of the second separated liquid enters the second distillation treatment and is distilled at a vacuum degree of -25KPa and a temperature of 150°C. 80% of the total mass of the third separated liquid enters the third distillation treatment and is distilled at a vacuum degree of -15KPa and a temperature of 140°C to obtain n-butane to produce succinic anhydride and butyrolactone and butanediol: the yield of succinic anhydride is 99.5%, the yield of butyrolactone is 0.2%, and the yield of butanediol is 0.3%.

[0078] Example 8

[0079] 50 g of VPO catalyst was loaded into the oxidation reactor. The concentration of n-butane entering the oxidation reactor was 5%. The reaction pressure was 2.5 MPa and the reaction temperature was 300°C.

[0080] 50g of 15% Ni-MCM-41 catalyst was loaded into a three-stage tubular reactor of a fixed bed hydrogenation reaction system. The maleic anhydride solution was divided into three paths and entered the lower part of each stage of the reactor. The mass ratio of the maleic anhydride solution in the first hydrogenation reduction reaction, the second hydrogenation reduction reaction, and the third hydrogenation reduction reaction was 1:1.5:7.5. The process conditions of the reaction were as follows: the temperature of the first hydrogenation reduction reaction was 270°C, the pressure was 0.5MPa, and WHSV=0.1h -1 The temperature of the second hydrogenation reduction reaction is 200°C, the pressure is 0.5MPa, and WHSV=0.1h -1 The temperature of the third hydrogenation reduction reaction is 170°C, the pressure is 2MPa, and WHSV=0.3h -1 .

[0081] The reaction product is discharged from the upper part of the three-stage tubular reactor of the fixed bed hydrogenation reaction system, and the first separated liquid, the second separated liquid and the third separated liquid are respectively discharged from the bottom of the gas-liquid separation tank. 100% of the total mass of the first separated liquid enters the first distillation treatment and is distilled at a vacuum degree of -40KPa and a temperature of 160°C. 75% of the total mass of the second separated liquid enters the second distillation treatment and is distilled at a vacuum degree of -20KPa and a temperature of 160°C. 85% of the total mass of the third separated liquid enters the third distillation treatment and is distilled at a vacuum degree of -10KPa and a temperature of 150°C to obtain n-butane to produce succinic anhydride and butyrolactone and butanediol: the yield of succinic anhydride is 98.5%, the yield of butyrolactone is 0.5%, and the yield of butanediol is 1%.

[0082] Example 9

[0083] 50 g of VPO catalyst was loaded into the oxidation reactor. The concentration of n-butane entering the oxidation reactor was 5%. The reaction pressure was 2.5 MPa and the reaction temperature was 300°C.

[0084] 50g of 15% Ni-MCM-41 catalyst was loaded into a three-stage tubular reactor of a fixed bed hydrogenation reaction system. The maleic anhydride solution was divided into three routes and entered the lower part of each stage of the reactor. The mass ratio of the maleic anhydride solution in the first hydrogenation reduction reaction, the second hydrogenation reduction reaction, and the third hydrogenation reduction reaction was 1.5:1.5:7. The process conditions of the reaction were as follows: the temperature of the first hydrogenation reduction reaction was 270°C, the pressure was 1MPa, and WHSV=0.5h -1The temperature of the second hydrogenation reduction reaction is 200°C, the pressure is 1MPa, and WHSV=0.5h -1 The temperature of the third hydrogenation reduction reaction is 170°C, the pressure is 1MPa, and WHSV=0.5h -1 .

[0085] The reaction product is discharged from the upper part of the three-stage tubular reactor of the fixed bed hydrogenation reaction system, and the first separated liquid, the second separated liquid and the third separated liquid are respectively discharged from the bottom of the gas-liquid separation tank. 90% of the total mass of the first separated liquid enters the first distillation treatment and is distilled at a vacuum degree of -35 KPa and a temperature of 165°C. 70% of the total mass of the second separated liquid enters the second distillation treatment and is distilled at a vacuum degree of -15 KPa and a temperature of 165°C. 90% of the total mass of the third separated liquid enters the third distillation treatment and is distilled at a vacuum degree of -15 KPa and a temperature of 155°C to obtain n-butane to produce succinic anhydride and butyrolactone and butanediol: the yield of succinic anhydride is 99.5%, the yield of butyrolactone is 0.3%, and the yield of butanediol is 0.2%.

[0086] Example 10

[0087] 50 g of VPO catalyst was loaded into the oxidation reactor. The concentration of n-butane entering the oxidation reactor was 15%, the reaction pressure was 3 MPa, and the reaction temperature was 200°C.

[0088] 50g of 15% Ni-MCM-41 catalyst was loaded into a three-stage tubular reactor of a fixed bed hydrogenation reaction system. The maleic anhydride solution was divided into three routes and entered the lower part of each stage of the reactor. The mass ratio of the maleic anhydride solution in the first hydrogenation reduction reaction, the second hydrogenation reduction reaction, and the third hydrogenation reduction reaction was 1:2:7. The process conditions of the reaction were as follows: the temperature of the first hydrogenation reduction reaction was 270°C, the pressure was 3MPa, and WHSV=0.5h -1 The temperature of the second hydrogenation reduction reaction is 200°C, the pressure is 3MPa, and WHSV=0.5h -1 The temperature of the third hydrogenation reduction reaction is 170°C, the pressure is 1.5MPa, and WHSV=0.5h -1 .

[0089] The reaction product is discharged from the upper part of the three-stage tubular reactor of the fixed bed hydrogenation reaction system, and the first separated liquid, the second separated liquid and the third separated liquid are respectively discharged from the bottom of the gas-liquid separation tank. 85% of the total mass of the first separated liquid enters the first distillation treatment and is distilled at a vacuum degree of -30 KPa and a temperature of 170°C. 65% of the total mass of the second separated liquid enters the second distillation treatment and is distilled at a vacuum degree of -10 KPa and a temperature of 170°C. 85% of the total mass of the third separated liquid enters the third distillation treatment and is distilled at a vacuum degree of -10 KPa and a temperature of 160°C to obtain n-butane to produce succinic anhydride and butyrolactone and butanediol: the yield of succinic anhydride is 99.7%, the yield of butyrolactone is 0.1%, and the yield of butanediol is 0.2%.

[0090] Embodiment 11

[0091] 50 g of VPO catalyst was loaded into the oxidation reactor. The concentration of n-butane entering the oxidation reactor was 10%. The reaction pressure was 3 MPa and the reaction temperature was 200°C.

[0092] 50g of 15% Ni-MCM-41 catalyst was loaded into a three-stage tubular reactor of a fixed bed hydrogenation reaction system. The maleic anhydride solution was divided into three paths and entered the lower part of each stage of the reactor. The mass ratio of the maleic anhydride solution in the first hydrogenation reduction reaction, the second hydrogenation reduction reaction, and the third hydrogenation reduction reaction was 2:1:7. The process conditions of the reaction were as follows: the temperature of the first hydrogenation reduction reaction was 270°C, the pressure was 1.0MPa, and WHSV=0.5h -1 ; The temperature of the second hydrogenation reduction reaction is 200°C, the pressure is 1.0MPa, and WHSV=0.5h -1 The temperature of the third hydrogenation reduction reaction is 170°C, the pressure is 1.5MPa, and WHSV=0.5h -1 .

[0093] The reaction product is discharged from the upper part of the three-stage tubular reactor of the fixed bed hydrogenation reaction system, and the first separated liquid, the second separated liquid and the third separated liquid are respectively discharged from the bottom of the gas-liquid separation tank. 80% of the total mass of the first separated liquid enters the first distillation treatment and is distilled at a vacuum degree of -25 KPa and a temperature of 175°C. 60% of the total mass of the second separated liquid enters the second distillation treatment and is distilled at a vacuum degree of -15 KPa and a temperature of 175°C. 80% of the total mass of the third separated liquid enters the third distillation treatment and is distilled at a vacuum degree of -15 KPa and a temperature of 165°C to obtain n-butane to produce succinic anhydride and butyrolactone and butanediol: the yield of succinic anhydride is 99.1%, the yield of butyrolactone is 0.4%, and the yield of butanediol is 0.5%.

[0094] Example 12

[0095] The difference from Example 1 is that the conditions of the first hydrogenation reduction reaction are: temperature of 270°C, absolute pressure of 2 MPa, mass space velocity of 1 h -1 , n-butane is obtained to produce succinic anhydride and butyrolactone and butanediol: the yield of succinic anhydride is 99.5%, the yield of butyrolactone is 0.2%, and the yield of butanediol is 0.3%.

[0096] Example 13

[0097] The difference from Example 1 is that the conditions of the first hydrogenation reduction reaction are: temperature of 300°C, absolute pressure of 2.5 MPa, mass space velocity of 2 h -1 , n-butane is obtained to produce succinic anhydride and butyrolactone and butanediol: the yield of succinic anhydride is 99.0%, the yield of butyrolactone is 0.2%, and the yield of butanediol is 0.8%.

[0098] Embodiment 14

[0099] The difference from Example 1 is that the conditions of the first hydrogenation reduction reaction are: temperature of 200°C, absolute pressure of 0 MPa, mass space velocity of 4 h -1 , n-butane is used to produce succinic anhydride and butyrolactone and butanediol: the yield of succinic anhydride is 99.1%, the yield of butyrolactone is 0.8%, and the yield of butanediol is 0.1%.

[0100] Embodiment 15

[0101] The difference from Example 1 is that the conditions of the second hydrogenation reduction reaction are: temperature of 200°C, absolute pressure of 2 MPa, mass space velocity of 0.1 h -1 , n-butane is obtained to produce succinic anhydride and butyrolactone and butanediol: the yield of succinic anhydride is 98.5%, the yield of butyrolactone is 1.0%, and the yield of butanediol is 0.5%.

[0102] Example 16

[0103] The difference from Example 1 is that the conditions of the second hydrogenation reduction reaction are: temperature of 220°C, absolute pressure of 1.5 MPa, mass space velocity of 0.5 h -1 , n-butane is obtained to produce succinic anhydride and butyrolactone and butanediol: the yield of succinic anhydride is 97.5%, the yield of butyrolactone is 2%, and the yield of butanediol is 0.5%.

[0104] Embodiment 17

[0105] The difference from Example 1 is that the conditions of the second hydrogenation reduction reaction are: temperature of 100°C, absolute pressure of 0 MPa, mass space velocity of 5 h -1 , n-butane is obtained to produce succinic anhydride and butyrolactone and butanediol: the yield of succinic anhydride is 99.2%, the yield of butyrolactone is 0.2%, and the yield of butanediol is 0.6%.

[0106] Embodiment 18

[0107] The difference from Example 1 is that the conditions of the third hydrogenation reduction reaction are: temperature of 160°C, absolute pressure of 1.5 MPa, mass space velocity of 1.5 h -1 , and n-butane is used to produce succinic anhydride and butyrolactone and butanediol: the yield of succinic anhydride is 99.1%, the yield of butyrolactone is 0.1%, and the yield of butanediol is 0.9%.

[0108] Embodiment 19

[0109] The difference from Example 1 is that the conditions of the third hydrogenation reduction reaction are: temperature of 175°C, absolute pressure of 3.5 MPa, mass space velocity of 2 h -1 , and n-butane was used to produce succinic anhydride and butyrolactone and butanediol: the yield of succinic anhydride was 98.7%, the yield of butyrolactone was 0.5%, and the yield of butanediol was 0.8%.

[0110] Embodiment 20

[0111] The difference from Example 1 is that the conditions of the third hydrogenation reduction reaction are: temperature of 100°C, absolute pressure of 0 MPa, mass space velocity of 4 h -1 , and n-butane is used to produce succinic anhydride and butyrolactone and butanediol: the yield of succinic anhydride is 95.5%, the yield of butyrolactone is 2.8%, and the yield of butanediol is 1.7%.

[0112] Embodiment 21

[0113] The difference from Example 1 is that the mass ratio of the maleic anhydride-rich solution in the first hydrogenation reduction reaction, the second hydrogenation reduction reaction, and the third hydrogenation reduction reaction is 1:3:6., and n-butane is obtained to produce succinic anhydride and butyrolactone and butanediol: the yield of succinic anhydride is 99.2%, the yield of butyrolactone is 0.5%, and the yield of butanediol is 0.3%.

[0114] Embodiment 22

[0115] The difference from Example 1 is that the mass ratio of the maleic anhydride-rich solution in the first hydrogenation reduction reaction, the second hydrogenation reduction reaction, and the third hydrogenation reduction reaction is 4.5:4.5:5, and n-butane is obtained to produce succinic anhydride and butyrolactone and butanediol: the yield of succinic anhydride is 99.3%, the yield of butyrolactone is 0.4%, and the yield of butanediol is 0.3%.

[0116] Embodiment 23

[0117] The difference from Example 1 is that the mass ratio of the maleic anhydride-rich solution in the first hydrogenation reduction reaction, the second hydrogenation reduction reaction, and the third hydrogenation reduction reaction is 0:0:10, and n-butane is obtained to produce succinic anhydride and butyrolactone and butanediol: the yield of succinic anhydride is 99.3%, the yield of butyrolactone is 0.7%, and the yield of butanediol is 0%.

[0118] Embodiment 24

[0119] The difference from Example 1 is that the first separated liquid subjected to the first distillation treatment accounts for 70% of the total mass of the first separated liquid, and n-butane is obtained to produce succinic anhydride and butyrolactone and butanediol: the yield of succinic anhydride is 98.3%, the yield of butyrolactone is 0.3%, and the yield of butanediol is 1.4%.

[0120] Embodiment 25

[0121] The difference from Example 1 is that the first separated liquid subjected to the first distillation treatment accounts for 40% of the total mass of the first separated liquid, and n-butane is obtained to produce succinic anhydride and butyrolactone and butanediol: the yield of succinic anhydride is 99.1%, the yield of butyrolactone is 0.6%, and the yield of butanediol is 0.3%.

[0122] Embodiment 26

[0123] The difference from Example 1 is that the second separated liquid subjected to the second distillation treatment accounts for 70% of the total mass of the second separated liquid, and n-butane is obtained to produce succinic anhydride and butyrolactone and butanediol: the yield of succinic anhydride is 98.3%, the yield of butyrolactone is 1.4%, and the yield of butanediol is 0.3%.

[0124] Embodiment 27

[0125] The difference from Example 1 is that the second separated liquid subjected to the second distillation treatment accounts for 30% of the total mass of the second separated liquid, and n-butane is obtained to produce succinic anhydride and butyrolactone and butanediol: the yield of succinic anhydride is 99.2%, the yield of butyrolactone is 0.2%, and the yield of butanediol is 0.6%.

[0126] Embodiment 28

[0127] The difference from Example 1 is that the third separated liquid subjected to the third distillation treatment accounts for 60% of the total mass of the third separated liquid, and n-butane is obtained to produce succinic anhydride and butyrolactone and butanediol: the yield of succinic anhydride is 99.4%, the yield of butyrolactone is 0.3%, and the yield of butanediol is 0.3%.

[0128] Embodiment 29

[0129] The difference from Example 1 is that the third separation liquid for the third rectification treatment is 30% of the total mass of the third separation liquid, and n-butane is used to produce succinic anhydride co-producing γ-butyrolactone and butanediol: the yield of succinic anhydride is 87.2%, the yield of γ-butyrolactone is 10.6%, and the yield of butanediol is 2.2%.

[0130] Example 30

[0131] The difference from Example 1 is that the temperature of the oxidation reaction is 450 °C and the pressure of the oxidation reaction is 2 MPa, and n-butane is used to produce succinic anhydride co-producing γ-butyrolactone and butanediol: the yield of succinic anhydride is 99.2%, the yield of γ-butyrolactone is 0.5%, and the yield of butanediol is 0.3%.

[0132] The yields of succinic anhydride, γ-butyrolactone, and butanediol in the above examples and comparative examples are listed in Table 1.

[0133] Table 1

[0134]

[0135]

[0136] It should be noted that in theory, a small amount of butanediol is also generated in Example 23, but since the amount is too small, the specific content cannot be measured.

[0137] From the above description, it can be seen that the above examples of the present invention achieve the following technical effects:

[0138] In the present invention, n-butane and air first undergo an oxidation reaction in an oxidation reaction device to obtain a solution rich in maleic anhydride. Hydrogenation reduction reactions are respectively and synchronously carried out in the first tubular reactor, the second tubular reactor, and the third tubular reactor of the three-stage tubular reaction device, and the hydrogenation products are respectively post-treated by a post-treatment device. The process parameters are separately regulated in each tubular reactor. The process flow is simple and the operation is flexible, the reaction efficiency is high, and γ-butyrolactone and butanediol can be co-produced on the basis of obtaining high-purity succinic anhydride, thus solving the problems of high energy consumption, large investment, and large number of reactors in the prior art, and having good economic benefits and industrial application prospects.

[0139] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A reaction device for producing succinic anhydride and butyrolactone and butanediol, It is characterized in that The reaction device comprises: The oxidation reaction device (1) has a raw material inlet and a product outlet, wherein the raw material inlet is connected to an air source and a n-butane source respectively, and is used to carry out an oxidation reaction of n-butane with air to obtain a maleic anhydride-rich solution; A three-stage tubular reactor (2), comprising a first tubular reactor (3), a second tubular reactor (4) and a third tubular reactor (5), each independently of the other; the first tubular reactor (3), the second tubular reactor (4) and the third tubular reactor (5) each independently have an inlet and an outlet, and the inlets are respectively connected to the product outlet of the oxidation reaction device (1), and are used to simultaneously perform hydrogenation reduction reaction on the maleic anhydride-rich solution to obtain succinic anhydride, butyrolactone and butanediol, respectively; The post-processing equipment (6) has a plurality of liquid inlets and a plurality of liquid outlets, wherein the plurality of liquid inlets are respectively connected to the outlets of the first-stage tubular reactor (3), the second-stage tubular reactor (4) and the third-stage tubular reactor (5), and the post-processing equipment (6) includes three groups of separators, and the three groups of separators are respectively used to post-process the succinic anhydride, the butyrolactone and the butanediol.

2. The reaction device according to claim 1, It is characterized in that The three-stage tubular reactor (2) has a plurality of tubular reactors perpendicular to the horizontal direction, and the tubular reactors are filled with hydrogenation catalysts. In the horizontal direction, the three-stage tubular reactor (2) is divided into the first-stage tubular reactor (3), the second-stage tubular reactor (4) and the third-stage tubular reactor (5), which are independent of each other.

3. The reaction device according to claim 1 or 2, It is characterized in that The bottom of the tubes of the first-stage tube reactor (3), the second-stage tube reactor (4) and the third-stage tube reactor (5) are independently provided with bottom inlets, and a liquid inlet pipeline is provided on the pipeline of the oxidation reaction equipment (1) and the three-stage tube reactor (2), and the liquid inlet pipeline has a plurality of outlets, and the outlets of the liquid inlet pipeline are respectively connected to the bottom inlets of the tubes in a one-to-one correspondence, so as to transport the maleic anhydride-rich solution into the tubes respectively.

4. The reaction device according to any one of claims 1 to 3, It is characterized in that The tops of the tubes of the first-stage tube reactor (3), the second-stage tube reactor (4) and the third-stage tube reactor (5) are independently provided with a plurality of top inlets, and the top inlets are independently connected to a hydrogen source for respectively transporting hydrogen into the tubes.

5. The reaction device according to any one of claims 1 to 4, It is characterized in that The three groups of separators include a first group of separators, a second group of separators and a third group of separators, each group of separators independently includes a gas-liquid separation tank (7) and a distillation tower (8) connected in series, and the gas-liquid separation tank (7) is respectively connected to the outlets of the first section of tubular reactor (3), the second section of tubular reactor (4) and the third section of tubular reactor (5) in a one-to-one correspondence.

6. The reaction device according to claim 1, It is characterized in that A condenser (9) and a separation tower (10) are sequentially arranged on the pipeline connecting the oxidation reaction equipment (1) and the three-stage tube-in-tube reaction equipment (2).

7. A method for producing succinic anhydride and butyrolactone and butanediol by using the reaction device according to any one of claims 1 to 6, It is characterized in that The method comprises: Step S1, n-butane is oxidized with air to obtain a maleic anhydride-rich solution; Step S2, subjecting a portion of the maleic anhydride-rich solution to a first hydrogenation reduction reaction to obtain a first hydrogenation system; subjecting another portion of the maleic anhydride-rich solution to a second hydrogenation reduction reaction to obtain a second hydrogenation system; and subjecting the remaining portion of the maleic anhydride-rich solution to a third hydrogenation reduction reaction to obtain a third hydrogenation system; and Step S3, sequentially performing a first separation treatment on the first hydrogenation system to obtain butanediol; sequentially performing a second separation treatment on the second hydrogenation system to obtain butyrolactone; and sequentially performing a third separation treatment on the third hydrogenation system to obtain succinic anhydride.

8. The method according to claim 7, It is characterized in that The conditions of the first hydrogenation reduction reaction are: temperature of 250-300°C, and / or absolute pressure of 0.5-5 MPa, and / or mass space velocity of 0.1-3 h -1 The conditions for the second hydrogenation reduction reaction are preferably: a temperature of 180 to 220°C, and / or an absolute pressure of 0.5 to 5 MPa, and / or a mass space velocity of 0.1 to 3 h -1 The conditions of the third hydrogenation reduction reaction are preferably: a temperature of 150 to 175°C, and / or an absolute pressure of 0.5 to 5 MPa, and / or a mass space velocity of 0.1 to 3 h -1 ; Preferably, the mass ratio of the maleic anhydride-rich solution in the first hydrogenation reduction reaction, the second hydrogenation reduction reaction, and the third hydrogenation reduction reaction is 0.5-4.5:0.5-4.5:5-9.

9. The method according to claim 7 or 8, It is characterized in that The step S3 comprises: performing a first gas-liquid separation process on the first hydrogenation system to obtain a first separated gas and a first separated liquid; Returning part of the first separated liquid to the system of the first gas-liquid separation treatment, and performing the first distillation treatment on the remaining first separated liquid. Preferably, the first separated liquid subjected to the first distillation treatment accounts for 60 to 100% of the total mass of the first separated liquid. Preferably, the conditions of the first distillation treatment are a vacuum degree of -80 KPa to -10 KPa and a temperature of 100° C. to 200° C.; and / or performing a second gas-liquid separation process on the second hydrogenation system to obtain a second separated gas and a second separated liquid; Returning part of the second separated liquid to the system of the first gas-liquid separation treatment, and performing a second distillation treatment on the remaining second separated liquid. Preferably, the second separated liquid subjected to the second distillation treatment accounts for 50 to 80% of the total mass of the second separated liquid. Preferably, the conditions of the second distillation treatment are a vacuum degree of -60 KPa to -10 KPa and a temperature of 100° C. to 200° C.; and / or performing a third gas-liquid separation process on the third hydrogenation system to obtain a third separated gas and a third separated liquid; Part of the third separated liquid is returned to the second gas-liquid separation treatment system, and the remaining third separated liquid is subjected to a third distillation treatment. Preferably, the third separated liquid subjected to the third distillation treatment accounts for 50 to 90% of the total mass of the third separated liquid; preferably, the conditions for the third distillation treatment are a vacuum degree of -50 KPa to -10 KPa and a temperature of 100°C to 200°C.

10. The method according to any one of claims 7 to 9, It is characterized in that The preparation process of the maleic anhydride-rich solution also includes: The system obtained by the oxidation reaction is subjected to condensation treatment and separation treatment in sequence to obtain the maleic anhydride-rich solution; Preferably, the catalyst used in the oxidation reaction is a VPO catalyst; Preferably, the temperature of the oxidation reaction is 300 to 450° C., and preferably, the pressure of the oxidation reaction is 0 to 3 MPa.

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