A tetrahydrofuran sulfuration catalytic reactor and an industrial synthesis system of tetrahydrothiophene

Abstract

The application discloses a tetrahydrofuran sulfuration catalytic reactor and a tetra-thiophene industrial synthesis system, which comprises a shell provided with an inlet and an outlet and a catalyst filled in the shell, and the shell is wrapped with a segmented heat exchange device outside; a temperature sensor with different heights is longitudinally arranged at the bottom of the shell; and the heat exchange device and the temperature sensor are connected with a temperature control device. The temperature at different heights in the shell is measured by the temperature sensor, the segmented heat exchange device is arranged from top to bottom outside the shell, the heat exchange device is controlled by the temperature control device according to the temperature measured by the temperature sensor to perform heat exchange work on the shell, the temperature at different positions of the shell is uniform, precise temperature control is realized, and the catalytic efficiency of the catalytic reactor is improved.

Description

Technical Field

[0001] This invention relates to the field of tetrahydrothiophene synthesis technology, and in particular to a tetrahydrofuran sulfidation catalytic reactor and a tetrahydrothiophene industrial synthesis system. Background Technology

[0002] Tetrahydrothiophene is an important organic compound, mainly used as an odorant for fuel gases such as city gas, liquefied petroleum gas, and natural gas liquefaction, and can also be used as a raw material for pharmaceuticals and pesticides.

[0003] There are two main production processes for tetrahydrothiophene: thiophene catalytic hydrogenation and tetrahydrofuran sulfidation synthesis. While the thiophene catalytic hydrogenation method is technologically mature, the cost of the raw material thiophene is relatively high, the process is complex, and the technology is challenging, preventing it from achieving a significant market advantage. The tetrahydrofuran sulfidation synthesis method involves catalytically reacting tetrahydrofuran in a tetrahydrofuran catalytic reactor to directly sulfide the tetrahydrofuran into tetrahydrothiophene.

[0004] However, in the existing technology, the tetrahydrofuran sulfidation synthesis method uses a tetrahydrofuran catalytic reactor. During the reaction, the upper part of the catalyst bed is more prone to local overheating. The exothermic reaction causes overheating and catalyst deactivation. At the same time, it can cause partial overheating and cracking of the catalytic reactor, resulting in low catalytic efficiency in the reactor and high production energy consumption.

[0005] Furthermore, existing tetrahydrothiophene synthesis systems cannot reuse the heat generated by the reaction, resulting in waste. Chinese invention patent CN101768158A, published on July 7, 2010, discloses a method and process for synthesizing tetrahydrothiophene. In this method, 1,4-butanediol and hydrogen sulfide are heated to the reaction temperature, vaporized in a heat exchanger, and then introduced into a heated fixed-bed reactor to react with a pre-prepared catalyst. After heat exchange, the mixture enters a distillation column for further separation, and after condensation, it undergoes oil-water separation to collect tetrahydrothiophene. However, this patent does not reuse the heat generated by the reaction, resulting in waste and environmental damage. Summary of the Invention

[0006] To address the shortcomings in the aforementioned background technology, this invention proposes a tetrahydrofuran sulfidation catalytic reactor and a tetrahydrothiophene industrial synthesis system, which solves the problem of inaccurate temperature control in existing tetrahydrofuran catalytic reactors.

[0007] The technical solution of this invention is implemented as follows:

[0008] A tetrahydrofuran sulfidation catalytic reactor includes a shell with inlet and outlet and a catalyst disposed inside the shell. The shell is surrounded by a segmented heat exchange device. Temperature sensors at different heights are arranged longitudinally at the bottom of the shell. The heat exchange device and temperature sensors are connected to a temperature control device.

[0009] Furthermore, the heat exchange device includes a heat exchange sleeve sleeved on the outside of the shell, there are multiple heat exchange sleeves, and an insulation layer is provided between every two heat exchange sleeves; the heat exchange sleeves are filled with industrial water or industrial oil for heat exchange.

[0010] Furthermore, the tube is equipped with three temperature sensors, and the ratio of the heights of the three temperature sensors extending into the catalyst is 1:2:3.

[0011] Furthermore, the inlet of the housing is provided with an inlet pipe, and one end of the inlet pipe located inside the housing is provided with an axially extending bent section, and a baffle is provided inside the housing directly opposite the bent section.

[0012] Furthermore, the spoiler is an inverted U-shaped structure, a similar inverted U-shaped structure, an M-shaped structure, a similar M-shaped structure, a cylindrical structure, an arc-shaped structure, or an irregular structure with multiple bends, with the opening facing the bend section.

[0013] Furthermore, the end of the bent section is connected to a guide member with an opening facing the turbulence member. The upper end of the guide member is open, and the bottom is provided with a base plate, and the middle part of the base plate is connected to the bent section. The turbulence member is located inside the opening of the guide member and is in clearance fit with the guide member.

[0014] Furthermore, the catalyst is an r-Al2O3 supported catalyst; the active component of the r-Al2O3 supported catalyst includes rare earth elements or contains Mo or palladium salts.

[0015] A tetrahydrothiophene industrial synthesis system includes a tetrahydrofuran sulfidation catalytic reactor as described in any one of the above claims, and further includes a hydrogen sulfide storage tank, a tetrahydrofuran storage tank, an oil-water separator, a crude product tank, a distillation column, and a condenser. The hydrogen sulfide storage tank and the tetrahydrofuran storage tank are respectively connected to the inlet end of the tetrahydrofuran sulfidation catalytic reactor through a first set of heat exchangers and a second set of heat exchangers. The outlet end of the tetrahydrofuran sulfidation catalytic reactor is sequentially connected to the oil-water separator, the crude product tank, the distillation column, and the condenser through a third heat exchanger.

[0016] Furthermore, the first set of heat exchangers includes heat exchanger A and heat exchanger B, and the hydrogen sulfide storage tank is connected to the inlet end of the tetrahydrofuran sulfidation catalytic reactor in sequence through heat exchanger A and heat exchanger B; the second set of heat exchangers includes heat exchanger C, heat exchanger D and heat exchanger E; the tetrahydrofuran storage tank is connected to the inlet end of the tetrahydrofuran sulfidation catalytic reactor in sequence through heat exchanger C, heat exchanger D and heat exchanger E, and the outlet end of the tetrahydrofuran sulfidation catalytic reactor is connected to the third heat exchanger through heat exchanger C.

[0017] Furthermore, the distillation column includes distillation column A and distillation column B connected in sequence, and the condenser includes condenser A and condenser B respectively connected to distillation column A and distillation column B.

[0018] The beneficial effects of this invention are:

[0019] 1. This invention measures the temperature at different heights inside the shell using a temperature sensor. By setting segmented heat exchange devices from top to bottom outside the shell, and controlling the heat exchange devices to exchange heat with the shell based on the temperature measured by the temperature sensor, the invention achieves precise temperature control of the catalytic reaction process, avoids catalyst deactivation due to overheating, and improves the catalytic efficiency of the catalytic reactor.

[0020] 2. This invention uses the combined action of a flow-disrupting element and a flow-guiding element to turbulently flow the material entering through the inlet pipe, resulting in a more uniform material distribution and thus improving the efficiency of the catalyst. At the same time, it also makes the heat distribution on the surface of the catalyst bed uniform, thereby extending the service life of the catalyst.

[0021] 3. The present invention transfers the reaction heat of the tetrahydrofuran sulfidation catalytic reactor to a heat exchanger to heat the tetrahydrofuran added to the tetrahydrofuran sulfidation catalytic reactor, while the reaction products are cooled down, realizing the reuse of heat and achieving the purpose of energy saving and emission reduction.

[0022] 4. The present invention has the advantages of simple process, low investment cost and no waste gas or solid waste in the direct sulfidation synthesis of tetrahydrofuran. Attached Figure Description

[0023] To more clearly illustrate the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the structure of the tetrahydrofuran sulfidation catalytic reactor of the present invention;

[0025] Figure 2 This is a schematic diagram of the industrial synthesis system for tetrahydrothiophene of the present invention. Detailed Implementation

[0026] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] like Figure 1As shown in Embodiment 1 of the present invention, a tetrahydrofuran sulfidation catalytic reactor is used for the catalytic synthesis of tetrahydrothiophene via tetrahydrofuran sulfidation. The tetrahydrofuran sulfidation catalytic reactor includes a shell 101 with inlet and outlet. An inlet pipe 106 is provided on one side of the top of the shell 101, and a product outlet 107 is provided at the bottom. The shell 101 can be rectangular, cubic, cylindrical, or prism in shape. In this embodiment, the shell 101 is cylindrical. A catalyst is disposed inside the shell 101. Tetrahydrofuran and hydrogen sulfide are introduced into the shell 101 through the inlet pipe 106, and tetrahydrothiophene is synthesized via sulfidation catalytic synthesis under the action of the catalyst. A heat exchange device 102 with upper and lower sections is wrapped around the outside of the shell 101. Multiple temperature sensors 104 are provided on the shell 101 for inserting into different heights within the catalyst to detect the temperature at different heights within the catalyst. The heat exchange device 102 and the temperature sensors 104 are connected to a temperature control device. The temperature control device employs existing technology and includes a processor connected to the temperature control and flow rate control mechanism of the heat exchange device 102. The flow rate and temperature of the medium in the heat exchange device 102 are adjusted and controlled through this mechanism. The temperature control and flow rate control mechanisms of the heat exchange device 102 are existing technologies and will not be described in detail here. This invention uses a temperature sensor 104 to monitor the catalyst bed in real time, measuring the temperature of the catalyst bed at different heights within the shell 101. The temperature signal is converted into an electrical signal and transmitted to the processor of the temperature control device. The processor then transmits the signal to the temperature control and flow rate control mechanism of the heat exchange device 102. By changing the flow rate and / or temperature of the medium in the heat exchange device 102, the heat exchange temperature is adjusted, thus controlling the temperature of the shell 101. This ensures uniform temperature at different locations within the shell 101, achieving precise temperature control, preventing catalyst deactivation due to overheating, and improving the catalytic efficiency of the catalytic reactor.

[0028] Furthermore, such as Figure 1 As shown, the heat exchange device 102 includes a heat exchange sleeve fitted around the outside of the shell 101, and multiple heat exchange sleeves are arranged from top to bottom on the outside of the shell 101 to achieve segmented temperature control of the reaction inside the shell 101. The heat exchange sleeves contain industrial water or industrial oil for heat exchange.

[0029] Furthermore, the temperature sensor 104 is one of the following: resistance temperature detector (RTD), thermocouple, or thermoelectric voltage detector (TCD). In this embodiment, as... Figure 1 As shown, there are three temperature sensors 104: temperature sensor a, temperature sensor b, and temperature sensor c. The ratio of the heights of the three temperature sensors 104 extending into the catalyst, i.e., the effective lengths extending into the catalyst bed, is 1:2:3. Furthermore, the lines connecting the top-view projections of the distribution positions of the three temperature sensors 104 within the housing 101 form an equilateral triangle.

[0030] Furthermore, such as Figure 1 As shown, the inlet pipe 106 of the housing 101 extends from one end inside the housing 101 to the axial position of the housing 101, and the end of the inlet pipe 106 is provided with an axially upward extending bent section, and a baffle 103 is provided in the middle of the top of the housing 101, directly opposite the bent section.

[0031] Furthermore, such as Figure 1 As shown, in this embodiment, the flow-dispersing element 103 is an inverted U-shaped structure with its opening facing downwards towards the bend section. The opening of the inverted U-shaped structure is directly opposite the outlet of the bend section. The flow-dispersing element 103 turbulents the material entering through the inlet pipe 106, resulting in a more uniform material distribution. In other embodiments, the flow-dispersing element 103 is a downward-facing inverted U-shaped structure, an M-shaped structure, a cylindrical structure with a closed top, an arc-shaped structure, or an irregular structure with multiple bends. The irregular structure with multiple bends can be wavy, or formed by a smooth transition between the ends of several inverted U-shaped structures via arc-shaped transition sections.

[0032] Furthermore, such as Figure 1 As shown, the upper end of the bent section is connected to a guide member 105 with an opening facing the baffle member 103. In this embodiment, the guide member 105 is a cylindrical structure with an open upper end and a bottom plate, and the middle part of the bottom plate is connected to the upper end of the bent section; the baffle member 103 is located inside the opening of the guide member 105, and there is a gap between the baffle member 103 and the guide member 105 for material to pass through. The combined action of the baffle member 103 and the guide member 105 further makes the material distribution more uniform.

[0033] Furthermore, the catalyst filled inside the shell of the tetrahydrofuran sulfidation catalytic reactor is an r-Al2O3 supported catalyst; the active component of the r-Al2O3 supported catalyst includes rare earth elements or one of Mo salts or palladium salts.

[0034] Example 2, an industrial synthesis system for tetrahydrothiophene, such as Figure 2 As shown, the tetrahydrofuran sulfidation catalytic reactor, including any of the above-mentioned components, further includes a hydrogen sulfide storage tank 1, a tetrahydrofuran storage tank 2, an oil-water separator 4, a crude product tank 5, a distillation column, and a condenser. The hydrogen sulfide storage tank 1 and the tetrahydrofuran storage tank 2 are respectively connected to the inlet end of the tetrahydrofuran sulfidation catalytic reactor through a first set of heat exchangers and a second set of heat exchangers. The outlet end of the tetrahydrofuran sulfidation catalytic reactor is sequentially connected to the oil-water separator 4, the crude product tank 5, the distillation column, and the condenser through a third heat exchanger 10.

[0035] Furthermore, such as Figure 2As shown, the first set of heat exchangers includes heat exchanger A16 and heat exchanger B3. Hydrogen sulfide storage tank 1 is connected to the inlet of the tetrahydrofuran sulfidation catalytic reactor via heat exchangers A16 and B3. The second set of heat exchangers includes heat exchangers C12, D11, and E6. Tetrahydrofuran storage tank 2 is connected to the inlet of the tetrahydrofuran sulfidation catalytic reactor via heat exchangers C12, D11, and E6, and the outlet of the tetrahydrofuran sulfidation catalytic reactor is connected to the third heat exchanger 10 via heat exchanger C12. Specifically, the hydrogen sulfide storage tank 1 is connected to the inlet of heat exchanger A16, the outlet of heat exchanger A16 is connected to the inlet of heat exchanger B3, and the outlet of heat exchanger B3 is connected to the inlet of the tetrahydrofuran sulfidation catalytic reactor. Tetrahydrofuran storage tank 2 is connected to the inlet of the tube side (or shell side) of heat exchanger C12. The outlet of the tube side (or shell side) of heat exchanger C12 is connected to the inlet of heat exchanger D11. The outlet of heat exchanger D11 is connected to the inlet of heat exchanger E6. The outlet of heat exchanger E6 is connected to the inlet of the tetrahydrofuran sulfidation catalytic reactor. Furthermore, the outlet of the tetrahydrofuran sulfidation catalytic reactor is connected to the inlet of the shell side (or tube side) of heat exchanger C12, transferring the reaction heat from the tetrahydrofuran sulfidation catalytic reactor to heat the tetrahydrofuran added to the reactor. Simultaneously, the reaction product, crude tetrahydrothiophene, is cooled, achieving heat recovery and utilization. The outlet of the shell side (or tube side) of heat exchanger C12 is connected to the inlet of the third heat exchanger 10. The outlet of the third heat exchanger 10 is connected to the inlet of the oil-water separator 4. The crude tetrahydrothiophene enters the oil-water separator 4 after heat exchange in the third heat exchanger 10. The oil-water separator separates the crude product produced by the tetrahydrofuran sulfidation catalytic reactor, and the separated oil phase enters the inlet of the crude product tank 5. The crude product tank 5 is used to store crude tetrahydrothiophene product.

[0036] Furthermore, such as Figure 2 As shown, the distillation column includes distillation column A13 and distillation column B15 connected in sequence, and crude product tank 5 is connected to distillation column A13 and distillation column B15 in sequence. The condenser includes condenser A7 and condenser B14. Condenser A7 is connected to distillation column A13 to condense the top material of distillation column A13, and condenser B14 is connected to distillation column B15 to condense the top material of distillation column B15. The tetrahydrothiophene crude product from crude product tank 5 enters distillation column A13, which is used to separate unreacted hydrogen sulfide from the tetrahydrothiophene crude product. The bottom components separated in distillation column A13 enter distillation column B15, which is used to separate unreacted tetrahydrofuran from the material. The purified tetrahydrothiophene product is collected at the top of distillation column B15 after separation.

[0037] The process flow for the direct sulfidation synthesis of tetrahydrothiophene from tetrahydrofuran is as follows:

[0038] Tetrahydrofuran and hydrogen sulfide are added to a tetrahydrofuran sulfide catalytic reactor at a molar ratio of 1:2. During the addition of hydrogen sulfide, it is first treated by heat exchange in a first heat exchanger. The hot hydrogen sulfide flowing from the outlet of heat exchanger A16 enters the inlet of heat exchanger B3, and then enters the inlet of the tetrahydrofuran sulfide catalytic reactor. During the addition of tetrahydrofuran, it is first treated by heat exchange in a second heat exchanger. The hot tetrahydrofuran flowing from the outlet of heat exchanger E6 enters the inlet of the tetrahydrofuran sulfide catalytic reactor, where hydrogen sulfide reacts with tetrahydrofuran. The reacted product sequentially enters heat exchanger C12 for heat exchange, and then enters a third heat exchanger 10 for heat exchange. After heat exchange, it enters an oil-water separator 4 to separate the crude product. The upper layer is the oil phase, and the lower layer is the water phase. The oil phase, which is the crude tetrahydrothiophene product, is stored in the crude product tank 15. Subsequently, the crude tetrahydrothiophene product enters distillation column A13 to separate unreacted hydrogen sulfide from the crude product. The bottom fraction of distillation column A13 enters distillation column B15. Distillation column B15 separates unreacted tetrahydrofuran from the feed, while the purified tetrahydrothiophene product is collected at the top of the column. The yield of the obtained tetrahydrothiophene product is 99.5%.

[0039] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A tetrahydrofuran sulfidation catalytic reactor characterized by: The device includes a shell (101) with inlet and outlet and a catalyst filled inside the shell (101). A segmented heat exchange device (102) is wrapped around the outside of the shell (101). Temperature sensors (104) at different heights are longitudinally arranged at the bottom of the shell (101). The heat exchange device (102) and the temperature sensors (104) are connected to a temperature control device. The heat exchange device (102) includes a heat exchange sleeve sleeved outside the shell (101). There are multiple heat exchange sleeves, and an insulation layer is provided between every two heat exchange sleeves. The heat exchange sleeves are filled with industrial water or industrial fuel for heat exchange. An inlet pipe is provided at the inlet of the shell (101). The inlet pipe has an axially extending bent section at one end inside the shell (101), and a baffle (103) is provided inside the shell (101) facing the bent section; the end of the bent section is connected to a guide (105) with an opening facing the baffle (103), the upper end of the guide (105) is open, the bottom is provided with a base plate, and the middle part of the base plate is connected to the bent section; the baffle (103) is located inside the opening of the guide (105) and is clearance-fitted with the guide (105); the catalyst is an r-Al2O3 supported catalyst; the active components of the r-Al2O3 supported catalyst include rare earth elements or contain Mo salt or palladium salt.

2. The THF sulfidation catalytic reactor of claim 1, wherein: The temperature sensor (104) is provided in three parts, and the height ratio of the three temperature sensors (104) extending into the catalyst is 1:2:

3.

3. The tetrahydrofuran sulfidation catalytic reactor according to claim 1 or 2, characterized in that: The spoiler (103) is an inverted U-shaped structure, a similar inverted U-shaped structure, an M-shaped structure, a similar M-shaped structure, a cylindrical structure, an arc-shaped structure, or an irregular structure with multiple bends, with the opening facing the bend section.

4. An industrial synthesis system for tetrahydrothiophene, characterized in that: The reactor includes the tetrahydrofuran sulfidation catalytic reactor as described in any one of claims 1 to 3, and further includes a hydrogen sulfide storage tank (1), a tetrahydrofuran storage tank (2), an oil-water separator (4), a crude product tank (5), a distillation column, and a condenser. The hydrogen sulfide storage tank (1) and the tetrahydrofuran storage tank (2) are respectively connected to the inlet end of the tetrahydrofuran sulfidation catalytic reactor through a first set of heat exchangers and a second set of heat exchangers. The outlet end of the tetrahydrofuran sulfidation catalytic reactor is sequentially connected to the oil-water separator (4), the crude product tank (5), the distillation column, and the condenser through a third heat exchanger (10).

5. The tetrahydrothiophene industrial synthesis system according to claim 4, characterized in that: The first set of heat exchangers includes heat exchanger A (16) and heat exchanger B (3). The hydrogen sulfide storage tank (1) is connected to the inlet end of the tetrahydrofuran sulfide catalytic reactor in sequence through heat exchanger A (16) and heat exchanger B (3). The second set of heat exchangers includes heat exchanger C (12), heat exchanger D (11) and heat exchanger E (6). The tetrahydrofuran storage tank (2) is connected to the inlet end of the tetrahydrofuran sulfide catalytic reactor in sequence through heat exchanger C (12), heat exchanger D (11) and heat exchanger E (6). The outlet end of the tetrahydrofuran sulfide catalytic reactor is connected to the third heat exchanger (10) through heat exchanger C (12).

6. The tetrahydrothiophene industrial synthesis system according to claim 5, characterized in that: The distillation column includes distillation column A (13) and distillation column B (15) connected in sequence, and the condenser includes condenser A (7) and condenser B (14) connected to distillation column A (13) and distillation column B (15) respectively.

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