Tetrahydrolinalool preparation device and method

Abstract

The invention relates to the technical field of tetrahydrolinalool production, and discloses a tetrahydrolinalool preparation device and method.The tetrahydrolinalool preparation device comprises a shell, a feeding end, a first reaction zone, a second reaction zone and a discharging end are sequentially arranged in a communicating mode in the first direction, the feeding end is suitable for introducing raw materials and hydrogen into the first reaction zone, and the discharging end is suitable for introducing hydrogen into the second reaction zone; the discharging end is suitable for discharging products. A catalyst is arranged in a heat exchange tube in the first reaction region, two ends of the heat exchange tube are respectively communicated with the feeding end and the second reaction region, the first reaction region is provided with a partition plate assembly, the partition plate assembly divides the first reaction region into a first cavity and a second cavity which are distributed along a first direction, and the second cavity is communicated with the second reaction region. The second reaction area is communicated with a discharge end, and the discharge end is communicated with the second cavity through a return pipeline system. The product is introduced into the second reaction zone, so that the temperature in the second reaction zone is uniform, the local temperature in the second reaction zone can be prevented from being too high, and generation of impurities is avoided.

Description

Technical Field

[0001] The present application relates to the technical field of tetrahydrolinalool production, and specifically to a device and method for preparing tetrahydrolinalool. Background Art

[0002] Linalool is a compound widely found in nature. Due to its unique aroma characteristics, it is widely used in the formulation of high-end perfumes, daily chemical flavors and edible flavors. Tetrahydrolinalool is a product obtained by hydrogenation of linalool. It has a more stable structure and a more pleasant aroma. It is particularly suitable for the formulation of rose and lily of the valley fragrances. With the growing market demand for tetrahydrolinalool, it is particularly important to develop efficient and reliable tetrahydrolinalool production technology.

[0003] There are relatively few synthetic reaction equipments for linalool and tetrahydrolinalool in the related art, especially reactors suitable for hydrogenating linalool to prepare tetrahydrolinalool. Since the product is mainly used in the flavor and fragrance market, the control of impurities is extremely demanding, because impurities often have a serious impact on the aroma of the product. When the reaction liquid and hydrogen enter the adiabatic fixed bed together, if the internal temperature is uneven, resulting in excessive local temperature, impurities will be generated. Summary of the invention

[0004] The present application provides a reactor to solve the problem of more impurities in the product due to uneven temperature during the reaction process.

[0005] In the first aspect, the present application provides a tetrahydrolinalool preparation device, comprising a shell, in which a feed end, a first reaction zone, a second reaction zone and a discharge end are sequentially connected along a first direction, the feed end is suitable for introducing raw materials and hydrogen into the first reaction zone, and the discharge end is suitable for discharging products. Wherein, the first reaction zone includes a heat exchange tube, a catalyst is arranged in the heat exchange tube, and the two ends of the heat exchange tube are respectively connected to the feed end and the second reaction zone, and the first reaction zone is provided with a partition assembly, and the partition assembly divides the first reaction zone into a first cavity and a second cavity distributed along the first direction, and the second cavity is connected to the second reaction zone. The second reaction zone is connected to the discharge end, and the discharge end is connected to the second cavity through a return pipeline system.

[0006] Beneficial effects: The tetrahydrolinalool preparation device in the present application can control the temperature of the reaction of the raw materials and hydrogen in the heat exchange tube in stages through the first cavity and the second cavity, avoiding the large heat release due to the direct hydrogenation of dehydrolinalool or linalool and the tailing phenomenon in the late stage of the reaction. The tetrahydrolinalool preparation device in the present application solves the heat transfer problem in the reaction process. With the catalyst of this system, dehydrolinalool is used as a raw material, and a qualified tetrahydrolinalool product can be obtained by one-step hydrogenation, avoiding the complex separation process caused by impurity problems. At the same time, the set return pipeline system can re-introduce the product after the reaction into the second cavity, transfer heat to the reaction liquid in the heat exchange tube, promote the further reaction, control it within a reasonable temperature range, and after completing the heat exchange, mix it with the reaction liquid and enter the second reaction zone, so that the temperature of the reaction liquid entering the second reaction zone can be uniform. Because the product structure after the reaction is completed is stable, it can play a role in solvent dilution, so that it can avoid excessive local temperature in the second reaction zone, further control the generation of impurities, and at the same time, as the reaction temperature in the second reaction zone increases, the reaction rate is increased, and the tailing problem of the reaction is solved.

[0007] In an optional embodiment, the discharge end includes a liquid outlet and a gas outlet, both of which are connected to the inner cavity of the shell, and the liquid outlet and the gas outlet are arranged in sequence along the first direction, the gas outlet is suitable for discharging hydrogen, and the liquid outlet is suitable for discharging products, the first end of the return pipeline system is connected to the liquid outlet, and the second end of the return pipeline system is connected to the second cavity.

[0008] Beneficial effects: The liquid outlet and the gas outlet can realize gas-liquid separation of the material discharged from the second reaction zone, the liquid outlet is used to introduce the obtained product into the return pipeline system, and the gas outlet is used to discharge and recover the hydrogen derived from the second reaction zone.

[0009] In an optional embodiment, the feed end includes a feed port, an air inlet and a gas distributor. The feed port is communicated with the inner cavity of the shell, and the feed port is suitable for introducing raw materials into the inner cavity of the heat exchange tube. The air inlet is communicated with the inner cavity of the shell, and the air inlet is suitable for introducing hydrogen into the inner cavity of the heat exchange tube. The gas distributor is arranged in the shell and communicated with the air inlet.

[0010] Beneficial effect: The setting of the gas distributor can make the hydrogen introduced from the air inlet more evenly distributed, and cooperate with the introduction of raw materials through the feed inlet, so that the hydrogen and raw materials can be evenly mixed and then introduced into the heat exchange tube for reaction.

[0011] In an optional embodiment, it also includes a mixer, which is arranged between the heat exchange tube and the second reaction zone, the first end of the mixer is connected to the inner cavity of the heat exchange tube and the second cavity, the second end of the mixer is connected to the second reaction zone, and the second reaction zone is connected to the discharge end.

[0012] Beneficial effect: The mixer can mix the hydrogen and reaction liquid discharged from the heat exchange tube with the product introduced into the second cavity in the return pipeline system, so as to make the temperature of the reaction liquid entering the second reaction zone uniform, avoid excessive local temperature in the second reaction zone, and further control the generation of impurities.

[0013] In an optional embodiment, the diameter of the heat exchange tube is A, wherein 19mm≤A≤80mm, the length of the heat exchange tube is B, wherein 2000mm≤B≤6000mm, and the length ratio of the first cavity to the second cavity is C, wherein 2:1≤C≤3:1.

[0014] Beneficial effect: By limiting the length parameters, tube diameter parameters and ratio parameters of the first cavity and the second cavity of the heat exchange tube, the product quality can be further improved and the conversion rate can be increased.

[0015] In an optional embodiment, the diameter of the second reaction zone is D, wherein 500 mm ≤ D ≤ 4000 mm, and the length of the second reaction zone is E, wherein 2000 mm ≤ E ≤ 4000 mm.

[0016] Beneficial effect: By limiting the length parameters and diameter parameters of the second reaction zone, the product quality can be further improved and the conversion rate can be increased.

[0017] In a second aspect, the present application also provides a method for preparing tetrahydrolinalool, which uses the above-mentioned tetrahydrolinalool preparation device to prepare tetrahydrolinalool, comprising:

[0018] Hydrogen and raw materials are introduced into the heat exchange tube through the feed end, and catalytically react with the catalyst in the heat exchange tube to form a reaction liquid.

[0019] A cooling medium is introduced into the first cavity to exchange heat with the heat exchange tubes in the first cavity, and a product is introduced into the second cavity through the return pipeline system to exchange heat with the heat exchange tubes in the second cavity.

[0020] The reaction liquid in the heat exchange tube and the product introduced into the second cavity through the return pipeline system enter the second reaction zone together for adiabatic reaction to obtain the product.

[0021] The product produced in the second reaction zone enters the return pipeline system and is passed into the second cavity for circulation.

[0022] Beneficial effect: hydrogen and raw materials are introduced into the heat exchange tube from the feed end and first enter the heat exchange tube, and the raw materials and hydrogen undergo a hydrogenation reaction in the heat exchange tube under the action of the catalyst in the heat exchange tube, and the cooling medium in the first cavity removes the heat released by the reaction in time to ensure that the reaction temperature in the heat exchange tube is uniform, wherein the cooling medium in the first cavity is circulating water or warm water, and the cooled product enters the second cavity through the return pipe system, exchanges heat with the heat exchange tube, and then mixes with the reaction liquid in the heat exchange tube and enters the second reaction zone, and undergoes an adiabatic reaction in the second reaction zone, and then enters the discharge end for gas-liquid separation, the gas phase is discharged from the gas outlet and collected, the liquid phase is discharged from the liquid outlet into the return pipe system for collection, and the liquid phase is partially cooled and introduced into the second cavity again to participate in heat exchange and reaction.

[0023] In an optional embodiment, the prepared product is tetrahydrolinalool, the raw material is dehydrolinalool, tetrahydrolinalool is also introduced into the feed end, the ratio of tetrahydrolinalool to dehydrolinalool is F, wherein 0:1≤F≤2:1, and the mass ratio of the product introduced into the second cavity through the return pipeline system to the reaction liquid in the heat exchange tube is G, wherein 5:1≤G≤20:1.

[0024] Beneficial effect: By limiting the ratio parameter of tetrahydrolinalool and dehydrolinalool introduced into the feed end and the mass ratio parameter of the product introduced into the second cavity through the return pipeline system and the reaction liquid in the heat exchange tube, the product quality and the conversion rate can be further improved.

[0025] In an optional embodiment, the temperature of the heat exchange tube located in the first cavity is H, wherein 30°C≤H≤70°C, the temperature of the heat exchange tube located in the second cavity is I, wherein 50°C≤I≤110°C, and the temperature of the second reaction zone is J, wherein 90°C≤J≤150°C.

[0026] Beneficial effect: By limiting the temperature parameters of the heat exchange tubes in the first cavity, the temperature parameters of the heat exchange tubes in the second cavity and the temperature parameters of the second reaction zone, the product quality can be further improved and the conversion rate can be increased.

[0027] In an optional embodiment, the feed flow rate of dehydrolinalool is K, wherein 400 kg / h≤K≤10000 kg / h, and the feed flow rate of hydrogen is L, wherein K≤L≤3K.

[0028] Beneficial effect: By limiting the feed flow rate parameters of dehydrolinalool and the feed flow rate parameters of hydrogen, the product quality can be further improved and the conversion rate can be increased. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0030] Figure 1 This is a schematic diagram of the structure of a reactor according to an embodiment of the present application.

[0031] Description of reference numerals:

[0032] 1. Shell; 2. Feed end; 2001. Feed port; 2002. Air inlet; 2003. Gas distributor; 3. First reaction zone; 3001. Heat exchange tube; 3002. First cavity; 3003. Second cavity; 4. Second reaction zone; 5. Discharge end; 5001. Liquid outlet; 5002. Air outlet; 6. Mixer; 7. Partition assembly; 8. Water inlet; 9. Water outlet; 10. Tank body; 11. Pump body; 12. Heat exchanger; 13. First baffle; 14. Second baffle; X, first direction. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of this application.

[0034] Combine the following Figure 1 , describing an embodiment of the present application.

[0035] According to an embodiment of the present application, on the one hand, a tetrahydrolinalool preparation device is provided, comprising a housing 1, wherein a feed end 2, a first reaction zone 3, a second reaction zone 4 and a discharge end 5 are sequentially connected and arranged in the housing 1 along a first direction X, wherein the feed end 2 is suitable for introducing raw materials and hydrogen into the first reaction zone 3, and the discharge end 5 is suitable for discharging products. Among them, the first reaction zone 3 comprises a heat exchange tube 3001, wherein a catalyst is arranged in the heat exchange tube 3001, and both ends of the heat exchange tube 3001 are respectively connected to the feed end 2 and the second reaction zone 4, and the first reaction zone 3 is provided with a partition assembly 7, wherein the partition assembly 7 separates the first reaction zone 3 into a first cavity 3002 and a second cavity 3003 distributed along the first direction X, and the second cavity 3003 is connected to the second reaction zone 4. The second reaction zone 4 is connected to the discharge end 5, and the discharge end 5 is connected to the second cavity 3003 through a return pipeline system, and the second reaction zone 4 is configured as an adiabatic fixed bed.

[0036] It should be noted that the tetrahydrolinalool preparation device in the present application is suitable for gas-liquid-solid three-phase hydrogenation reaction, for example, suitable for hydrogenating dehydrolinalool to produce linalool or tetrahydrolinalool, and hydrogenating linalool to produce tetrahydrolinalool.

[0037] In this embodiment, the tetrahydrolinalool preparation device in the present application can perform staged temperature control on the reaction of the raw material and hydrogen in the heat exchange tube 3001 through the first cavity 3002 and the second cavity 3003, thereby avoiding the large heat release due to direct hydrogenation of dehydrolinalool or linalool and the tailing phenomenon in the late stage of the reaction. The tetrahydrolinalool preparation device in the present application solves the heat transfer problem in the reaction process. With the catalyst of this system, dehydrolinalool is used as a raw material, and a qualified tetrahydrolinalool product can be obtained by one-step hydrogenation, thereby avoiding the complicated separation process caused by impurity problems. At the same time, the return pipeline system can reintroduce the product after the reaction into the second cavity 3003, transfer heat from the reaction liquid in the heat exchange tube 3001, promote further reaction, control it within a reasonable temperature range, and after completing the heat exchange, mix it with the reaction liquid and enter the second reaction zone 4, so that the temperature of the reaction liquid entering the second reaction zone 4 can be uniform. Since the product structure after the reaction is completed is stable, it can play a role of solvent dilution, so that the local temperature in the second reaction zone 4 is prevented from being too high, and the generation of impurities is further controlled. At the same time, as the reaction temperature in the second reaction zone 4 increases, the reaction rate is improved, solving the tailing problem of the reaction.

[0038] In one embodiment, a plurality of heat exchange tubes 3001 may be provided, and the plurality of heat exchange tubes 3001 may be arranged in the shell 1 in a square straight row, a square staggered row, an equilateral triangle arrangement, a 45° angle arrangement, a circular arrangement, or the like.

[0039] In one embodiment, the catalyst used in the heat exchange tube 3001 and the second reaction zone 4 may be one or more of a precious metal catalyst or a supported metal catalyst with Pd, Pt, Rh, Ru, etc. as an active center, or a supported non-precious metal catalyst with Ni, Cu, Co, etc. as an active center.

[0040] In one embodiment, the discharge end 5 includes a liquid outlet 5001 and a gas outlet 5002, both of which are connected to the inner cavity of the shell 1, and the liquid outlet 5001 and the gas outlet 5002 are arranged in sequence along the first direction X, the gas outlet 5002 is suitable for discharging hydrogen, and the liquid outlet 5001 is suitable for discharging products. The first end of the return pipeline system is connected to the liquid outlet 5001, and the second end of the return pipeline system is connected to the second cavity 3003.

[0041] In this embodiment, the liquid outlet 5001 and the gas outlet 5002 can realize the gas-liquid separation of the material discharged from the second reaction zone 4. The liquid outlet 5001 is used to introduce the obtained product into the return pipeline system, and the gas outlet 5002 is used to discharge and recover the hydrogen derived from the second reaction zone 4.

[0042] In one embodiment, the feed end 2 includes a feed port 2001, an air inlet 2002 and a gas distributor 2003. The feed port 2001 is communicated with the inner cavity of the shell 1, and the feed port 2001 is suitable for introducing dehydrolinalool into the inner cavity of the heat exchange tube 3001. The air inlet 2002 is communicated with the inner cavity of the shell 1, and the air inlet 2002 is suitable for introducing hydrogen into the inner cavity of the heat exchange tube 3001. The gas distributor 2003 is arranged in the shell 1 and is communicated with the air inlet 2002.

[0043] Optionally, the hydrogen distributor is one of a multi-tube gas distributor 2003, a porous ring tube gas distributor 2003 and a Sos air distributor.

[0044] In this embodiment, the setting of the gas distributor 2003 can make the hydrogen introduced from the air inlet 2002 more evenly distributed, and cooperate with the introduction of dehydrolinalool through the feed port 2001, so that the hydrogen and dehydrolinalool can be evenly mixed and then introduced into the heat exchange tube 3001 for reaction.

[0045] In one embodiment, a mixer 6 is further included. The mixer 6 is arranged between the heat exchange tube 3001 and the second reaction zone 4. The first end of the mixer 6 is connected to the inner cavity of the heat exchange tube 3001 and the second cavity 3003. The second end of the mixer 6 is connected to the second reaction zone 4. The second reaction zone 4 is connected to the discharge end 5.

[0046] Optionally, the mixer 6 can be a conventional type of mixing equipment such as SK type, SV type, SL type, SX type, etc.

[0047] In this embodiment, the mixer 6 can mix the hydrogen and reaction liquid discharged from the heat exchange tube 3001 with the product introduced into the second cavity 3003 in the return pipeline system, so as to make the temperature of the reaction liquid entering the second reaction zone 4 uniform, avoid local excessive temperature in the second reaction zone 4, and further control the generation of impurities.

[0048] In one embodiment, the diameter of the heat exchange tube 3001 is A, wherein 19mm≤A≤80mm, the length of the heat exchange tube 3001 is B, wherein 2000mm≤B≤6000mm, and the length ratio of the first cavity 3002 to the second cavity 3003 is C, wherein 2:1≤C≤3:1.

[0049] In this embodiment, by limiting the length parameters and the tube diameter parameters of the heat exchange tube 3001 and the ratio parameters of the first cavity 3002 and the second cavity 3003, the product quality and the conversion rate can be further improved.

[0050] In one embodiment, the diameter of the second reaction zone 4 is D, wherein 500 mm ≤ D ≤ 4000 mm, and the length of the second reaction zone 4 is E, wherein 2000 mm ≤ E ≤ 4000 mm.

[0051] In this embodiment, by limiting the length parameter and diameter parameter of the second reaction zone 4, the product quality can be further improved and the conversion rate can be increased.

[0052] In one embodiment, the return pipeline system includes a tank body 10, a pump body 11 and a heat exchanger 12. The input end of the tank body 10 is in communication with the liquid outlet 5001, and the output end of the tank body 10 is suitable for discharging the product. The input end of the pump body 11 is in communication with the output end of the tank body 10, and the output end of the pump body 11 is in communication with the second cavity 3003. The heat exchanger 12 is in communication with the output end of the pump body 11, and the heat exchanger 12 can cool the product discharged from the pump body 11 so that it can exchange heat with the heat exchange pipe 3001 after entering the first cavity 3002.

[0053] In this embodiment, the tank body 10 is provided with two outlets, one of which is suitable for communicating with the input end of the pump body 11, so that the product can be passed into the second cavity 3003 for heat exchange and reaction. The other outlet of the tank body 10 can be used to discharge the product, so as to realize the collection and loading of the product.

[0054] In one embodiment, it also includes a first baffle 13 and a second baffle 14, both of which are provided in plurality. The plurality of first baffles 13 are alternately arranged in the first cavity 3002 along the first direction X, and the heat exchange tube 3001 passes through the plurality of first baffles 13. The intervals between the plurality of first baffles 13 form a connected passage, which can extend the flow distance of the cooling medium and improve the heat exchange effect. The plurality of second baffles 14 are alternately arranged in the second cavity 3003 along the first direction X, and the heat exchange tube 3001 passes through the plurality of second baffles 14. The intervals between the plurality of second baffles 14 form a connected passage, which can extend the flow distance of the product and improve the heat exchange effect.

[0055] According to an embodiment of the present application, on the other hand, a method for preparing tetrahydrolinalool is also provided, wherein the method uses the above-mentioned tetrahydrolinalool preparation device to prepare tetrahydrolinalool, comprising:

[0056] Hydrogen and dehydrolinalool are introduced into the heat exchange tube 3001 through the feed end 2 to react with the catalyst in the heat exchange tube 3001 to form a reaction liquid.

[0057] The cooling medium is introduced into the first cavity 3002 to exchange heat with the heat exchange tube 3001 located in the first cavity 3002 , and the product is introduced into the second cavity 3003 through the return pipeline system to exchange heat with the heat exchange tube 3001 located in the second cavity 3003 .

[0058] The reaction liquid in the heat exchange tube 3001 and the product introduced into the second cavity 3003 through the return pipeline system enter the second reaction zone 4 together for adiabatic reaction to obtain the product.

[0059] The product produced in the second reaction zone 4 enters the return pipeline system and is passed into the second cavity 3003 for circulation.

[0060] In this embodiment, hydrogen and dehydrolinalool are introduced into the heat exchange tube 3001 from the feed end 2 and first enter the heat exchange tube 3001. Dehydrolinalool and hydrogen undergo a hydrogenation reaction in the heat exchange tube 3001 under the action of the catalyst in the heat exchange tube 3001. The cooling medium in the first cavity 3002 removes the heat released by the reaction in time to ensure that the reaction temperature in the heat exchange tube 3001 is uniform. The cooling medium in the first cavity 3002 is circulating water or warm water. The cooled product is cooled by circulating water or warm water. The material pipeline system enters the second cavity 3003, exchanges heat with the heat exchange tube 3001, and then mixes with the reaction liquid in the heat exchange tube 3001 and enters the second reaction zone 4, and undergoes an adiabatic reaction in the second reaction zone 4, and then enters the discharge end 5 for gas-liquid separation, the gas phase is discharged from the gas outlet 5002 and collected, the liquid phase is discharged from the liquid outlet 5001 into the return pipeline system for collection, and the liquid phase is again introduced into the second cavity 3003 after partial cooling to participate in heat exchange and reaction.

[0061] In one embodiment, the prepared product is tetrahydrolinalool, the raw material is dehydrolinalool, and tetrahydrolinalool is also introduced into the feed end 2. The ratio of tetrahydrolinalool to dehydrolinalool is F, wherein 0:1≤F≤2:1. The mass ratio of the product introduced into the second cavity 3003 through the return pipeline system to the reaction liquid in the heat exchange tube 3001 is G, wherein 5:1≤G≤20:1.

[0062] In this embodiment, by limiting the ratio parameter of tetrahydrolinalool and dehydrolinalool introduced into the feed end 2 and the mass ratio parameter of the product introduced into the second cavity 3003 through the return pipeline system and the reaction liquid in the heat exchange tube 3001, the product quality and the conversion rate can be further improved.

[0063] In one embodiment, the temperature of the heat exchange tube 3001 located in the first cavity 3002 is H, wherein 30°C≤H≤70°C, the temperature of the heat exchange tube 3001 located in the second cavity 3003 is I, wherein 50°C≤I≤110°C, and the temperature of the second reaction zone 4 is J, wherein 90°C≤J≤150°C.

[0064] In this embodiment, by limiting the temperature parameters of the heat exchange tube 3001 in the first cavity 3002, the temperature parameters of the heat exchange tube 3001 located in the second cavity 3003 and the temperature parameters of the second reaction zone 4, the product quality and the conversion rate can be further improved.

[0065] In one embodiment, the feed flow rate of dehydrolinalool is K, wherein 400 kg / h≤K≤10000 kg / h, and the feed flow rate of hydrogen is L, wherein K≤L≤3K.

[0066] In this embodiment, by limiting the feed flow rate parameters of dehydrolinalool and the feed flow rate parameters of hydrogen, the product quality can be further improved and the conversion rate can be increased.

[0067] The present application provides Examples 1-10 and Comparative Examples 1-4, and the main raw material information sources are all common commercial raw materials unless otherwise specified. The catalyst used is one or more of the above-mentioned catalysts, and the dehydrolinalool used is commercially available dehydrolinalool with a purity of more than 99.6%. The product selectivity and conversion rate involved are analyzed by gas chromatography, and the gas chromatography conditions are: the gas chromatograph is Agilent 7820A, the capillary column (DB-5, 30m×0.25mm×0.25μm), the second-order program temperature rise, the initial temperature is 100℃, and after maintaining for 2 minutes, it is increased to 130℃ at a rate of 5℃ / min; then it is increased to 280℃ at a rate of 15℃ / min and maintained for 22min. The carrier gas is high-purity N2, with a split ratio of 20:1. The injection temperature is 290℃, the detector is FID, the detector temperature is 300℃, and the injection volume is 0.2μL. The inner cavity of the heat exchange tube 3001 located in the first cavity 3002 is set as an isothermal heat transfer zone, and the inner cavity of the heat exchange tube 3001 located in the second cavity 3003 is set as a product heat transfer zone.

[0068] Embodiment 1, referring to Table 1, the length of the heat exchange tube 3001 is 2000mm, the diameter of the heat exchange tube 3001 is 19mm, the arrangement of the heat exchange tube 3001 is an equilateral triangle arrangement, the number of the heat exchange tube 3001 is 400, the shell diameter of the first reaction zone 3 is 800mm, and a baffle is arranged on the outside of the heat exchange tube 3001 to meet the heat exchange requirements of the outer heat transfer medium. The length ratio of the first cavity 3002 and the second cavity 3003 is 2:1. The first cavity 3002 and the second cavity 3003 are separated by a partition assembly 7. The mixer 6 adopts an SK type mixing device to meet the mixing requirements of the product and the reaction liquid. The diameter of the second reaction zone 4 is 800mm, and the length of the second reaction zone 4 is 4000mm, wherein the second reaction zone 4 is configured as an adiabatic fixed bed.

[0069] Referring to Table 2, the raw material used in this embodiment is purchased or produced from outside with a purity of more than 99.6wt% dehydrolinalool. A hydrogen distributor connected to the air inlet 2002 is provided in the housing 1. The hydrogen park is provided by a pipeline network with a purity of more than 99.99wt%. The feed rate of dehydrolinalool is 3000kg / h. The ratio of dehydrolinalool introduced into the feed end 2 to the product is 1:0. The hydrogen feed flow rate is 140kg / h. The product and the product introduced into the second cavity 3003 through the return pipe system are The mass ratio of the reaction liquid in the heat exchange tube 3001 is 10:1, the temperature of the isothermal heat transfer zone is 50°C, the inlet control pressure of the first reaction zone 3 is 2.0MPaG, the heat transfer medium in the first cavity 3002 uses 32-42°C water for heat transfer, the product flow rate in the second cavity 3003 is 30000kg / h, the temperature of the product heat transfer zone is 50°C at the starting end and 100°C at the outlet end, the temperature entering the second reaction zone 4 is 100°C, and the outlet temperature of the second reaction zone 4 is 120°C.

[0070] Referring to Table 3, the experimental results show that: the conversion rate of the reaction is above 100%, the selectivity is above 99.8%, the pressure drop of the preparation equipment is 10 kPa, the product meets the purity index, the product aroma is identified by professional perfumers, and the identification results are objectively concluded based on statistical principles. The evaluation results are pure (score: 39.1-40.0 points), relatively pure (score: 36.0-39.0 points), acceptable (score: 32.0-35.9 points), fair (score: 28.0-31.9 points), qualified (score: 24.0-27.9 points), and unqualified (lower than 24.0). The result of the product fragrance evaluation is pure. Because dehydrolinalool contains more unsaturated double bonds, dehydrolinalool first undergoes hydrogenation reaction with hydrogen at a lower temperature to generate relatively stable dihydrolinalool or linalool. The reaction rate in this area is fast and the heat release is large. Circulating water is used to remove the heat generated by the reaction in time to control the temperature of the reaction system to be uniform, ensuring that dehydrolinalool will not undergo cyclization side reactions. The second cavity 3003 uses the product after the reaction to transfer heat from the material in the heat exchange tube 3001 to promote further reaction and control it within a reasonable temperature range; the product is mixed with the reaction liquid and enters the second reaction zone 4. Can the temperature entering the second reaction zone 4 be uniform? Because the product structure is stable, it plays a role of solvent dilution, so that it can avoid local excessive temperature in the second reaction zone 4, further control the generation of impurities, and at the same time, as the reaction temperature increases, the reaction rate is increased, solving the tailing problem of the reaction. The results show that the reaction effect is good.

[0071] Example 2, the tetrahydrolinalool preparation device used in Example 1 is used, except that: referring to Table 1, the length of the heat exchange tube 3001 is 6000 mm, the length ratio of the first cavity 3002 to the second cavity 3003 is 3:1, and the length of the second reaction zone 4 is 2000 mm.

[0072] Referring to Table 2, the temperature of the isothermal heat transfer zone is 70°C, the temperature of the product heat transfer zone is controlled at 70-90°C, and the temperature of the second reaction zone 4 is controlled at 90-100°C.

[0073] Other feed conditions and reaction conditions are consistent with those in Example 1.

[0074] Referring to Table 3, the experimental results show that: the conversion rate of the reaction is above 99.9%, the selectivity is above 99.7%, the pressure drop of the preparation device is 12kPa, the product meets the purity index, and the perfume appraiser generally uses the "three-point comparison method" to evaluate the fragrance. After identification by professional perfume appraisers, the result of the product evaluation is pure. Compared with Example 1, the preparation device increases the length of the heat exchange tube 3001, appropriately increases the temperature in the isothermal heat transfer zone, and shortens the length of the second reaction zone 4. The reaction result is good, indicating that the reaction process can also be completed when the initial reaction temperature is increased. The pressure drop increases slightly, mainly because the pressure drop of the first reaction zone 3 is slightly larger after the length of the heat exchange tube 3001 is increased, but it is within a controllable range.

[0075] Example 3, the tetrahydrolinalool preparation device used in Example 1 is used, except that: referring to Table 1, the shell diameter is 1000 mm, the number of heat exchange tubes 3001 is 800, and the diameter of the second reaction zone 4 is 2000 mm.

[0076] Referring to Table 2, the feed flow rate of dehydrolinalool is 6000 kg / h, and the feed flow rate of hydrogen is 280 kg / h.

[0077] Other conditions are consistent with those in Example 1.

[0078] Referring to Table 3, the experimental results show that: the conversion rate of the reaction is above 100%, the selectivity is above 99.7%, the pressure drop of the preparation device is 9kPa, the product meets the purity index, and the product is evaluated as pure by a professional perfumer. The diameter of the tetrahydrolinalool preparation device is increased, the number of available heat exchange tubes 3001 is increased, and the corresponding processing capacity of dehydrolinalool is increased. After the tetrahydrolinalool preparation device is enlarged, its heat transfer effect and reaction effect have not changed significantly. The tetrahydrolinalool preparation device is easy to enlarge and has great advantages in increasing production capacity.

[0079] Example 4 uses the tetrahydrolinalool preparation device used in Example 1, except that: referring to Table 2, the ratio of product to reaction liquid is 20:1, the temperature of the product heat transfer zone is controlled at 50-80° C., and the temperature of the second reaction zone 4 is controlled at 80-90° C. Other conditions are the same as those in Example 1.

[0080] Referring to Table 3, the experimental results show that: the conversion rate of the reaction is above 100%, the selectivity is above 99.8%, the pressure drop of the tetrahydrolinalool preparation device is 13kPa, the product meets the purity index, and the product fragrance evaluation result is pure after identification by professional perfumers. Compared with Example 1, the product ratio used in the product heat transfer zone of this reaction is larger, and after entering the second reaction zone 4, the adiabatic temperature rise is smaller. The results show that the product produced by the tetrahydrolinalool preparation device has higher purity, indicating that increasing the ratio of product to reaction liquid can better inhibit the occurrence of side reactions and produce better quality and higher purity products.

[0081] Example 5, the tetrahydrolinalool preparation device used in Example 1 is used, except that: referring to Table 1, the shell side diameter is 1200 mm, the diameter of the heat exchange tube 3001 is 50 mm, and the diameter of the second reaction zone 4 is 2000 mm.

[0082] Referring to Table 2, the product feed flow rate is 6000 kg / h and the hydrogen feed flow rate is 280 kg / h.

[0083] Other conditions are consistent with those in Example 1.

[0084] Referring to Table 3, the experimental results show that: the conversion rate of the reaction is above 99.9%, the selectivity is above 99.7%, the pressure drop of the tetrahydrolinalool preparation device is 9kPa, the product meets the purity index, and the product fragrance evaluation result is pure after identification by professional perfumers. The tetrahydrolinalool preparation device increases the diameter of the heat exchange tube 3001 in the isothermal heat transfer zone and the product heat transfer zone. The results show that the reaction effect is still good after increasing the diameter of the heat exchange tube 3001, and there is no obvious effect on the temperature control of the product heat transfer zone and the isothermal heat transfer zone. Compared with Example 1, the tetrahydrolinalool preparation device also increases the feed amount of dehydrolinalool and increases the reaction efficiency.

[0085] Example 6, the tetrahydrolinalool preparation device used in Example 3 is used, except that: referring to Table 1, the shell diameter is 1200 mm, the number of heat exchange tubes 3001 is 1000, the diameter of the second reaction zone 4 is 3000 mm, the heat exchange tubes 3001 are arranged in a corner triangle, and other conditions are consistent with Example 3.

[0086] Referring to Table 3, the experimental results show that: the conversion rate of the reaction is above 99.9%, the selectivity is above 99.6%, the pressure drop of the tetrahydrolinalool preparation device is 7 kPa, the product meets the purity index, and the product is evaluated by a professional perfumer as pure.

[0087] Example 7, the tetrahydrolinalool preparation device used in Example 1 is used, except that: referring to Table 2, the control temperature of the isothermal heat transfer zone is 70°C, the control temperature of the product heat transfer zone is 70-120°C, the control temperature of the second reaction zone 4 is 120-140°C, and the other conditions are consistent with Example 3.

[0088] Referring to Table 2, the experimental results show that: the conversion rate of the reaction is above 100%, the selectivity is above 99.3%, the pressure drop of the tetrahydrolinalool preparation device is 9kPa, the product meets the purity index, and the product is judged by a professional perfumer to be relatively pure. Compared with Example 3, the tetrahydrolinalool preparation device increases the temperature of the product heat transfer zone, the temperature of the corresponding product heat transfer zone and the second reaction zone 4 is also increased, and the outlet temperature of the second reaction zone 4 is increased from 120°C to 160°C. The selectivity is slightly reduced, and the corresponding fragrance evaluation result is reduced from pure to relatively pure, but the product quality is still within the control range, indicating that the impurity generation increases accordingly after the temperature is increased.

[0089] Example 8 uses the tetrahydrolinalool preparation device used in Example 1, except that: referring to Table 1, the ratio of the length of the heat exchange tube 3001 in the isothermal heat transfer zone to the length of the heat exchange tube 3001 in the product heat transfer zone is 3:1, and other conditions are consistent with Example 1.

[0090] Referring to Table 3, the experimental results show that: the conversion rate of the reaction is above 99.9%, the selectivity is above 99.8%, the pressure drop of the tetrahydrolinalool preparation device is 10kPa, the product meets the purity index, and the product is pure after being identified by a professional perfumer. Compared with Example 1, the length of the isothermal tubular reaction zone is increased, and the product quality is not affected.

[0091] Example 9, the tetrahydrolinalool preparation device used in Example 1 is used, except that: referring to Table 2, 2 times the product is used for dilution, the ratio of the product in the product heat transfer zone to the reaction liquid is 8:1, and other conditions are consistent with Example 1.

[0092] Referring to Table 3, the experimental results show that: the conversion rate of the reaction is above 100%, the selectivity is above 99.8%, the pressure drop of the tetrahydrolinalool preparation device is 9kPa, the product meets the purity index, and the product is pure after being identified by a professional perfumer. The product is added as a solvent to dilute the reaction liquid when entering the isothermal tubular reaction zone. When the conversion rate is 100%, the selectivity is also maintained at a high level. The reaction results show that adding the product to the reaction liquid is beneficial to inhibiting the occurrence of side reactions in each reaction zone and improving product quality.

[0093] Example 10, the tetrahydrolinalool preparation device used in Example 1 is used, except that: referring to Table 2, the ratio of the product to the reaction liquid is 5:1, the control temperature of the product heat transfer zone is 50-80°C, the control temperature of the second reaction zone 4 is 80-120°C, and the other conditions are consistent with Example 1.

[0094] Referring to Table 3, the experimental results show that: the conversion rate of the reaction is above 100%, the selectivity is above 99.4%, the pressure drop of the tetrahydrolinalool preparation device is 9kPa, the product meets the purity index, and the product fragrance evaluation result is relatively pure after identification by professional perfumers. Compared with Example 1, in the product heat transfer zone, the ratio of product to reaction liquid is reduced, resulting in a slight decrease in product purity, but the product quality is still within a controllable range. This result further illustrates that the product, as a diluent solvent, is conducive to reducing side reactions and improving product purity.

[0095] Comparative Example 1 (S1*) uses the tetrahydrolinalool preparation device used in Example 1, except that: the product is not used for dilution and heat transfer, the control temperature of the isothermal reaction zone and the product heat transfer zone is the same as in Example 1, the temperature of the second reaction zone 4 is 100-150°C, and the other conditions are consistent with Example 1.

[0096] The experimental results show that: the conversion rate of the reaction is above 100%, the selectivity is below 92.4%, the pressure drop of the tetrahydrolinalool preparation device is 5kPa, the product meets the purity but cannot meet the index requirements, and the product fragrance evaluation result is unqualified after identification by professional perfumers. The main reason is that the product is not diluted, the temperature rise of the reaction liquid in the second reaction zone 4 is high, and there are hot spots in the second reaction zone 4, resulting in the generation of some impurities, which will seriously affect the fragrance index.

[0097] Comparative Example 2 (S2*) uses the tetrahydrolinalool preparation device used in Example 1, except that the second reaction zone 4 is not used, and other conditions are consistent with Example 1.

[0098] The experimental results show that the conversion rate of the reaction is below 98%, the selectivity is below 81%, the pressure drop of the tetrahydrolinalool preparation device is 6kPa, the product meets the purity but cannot meet the index requirements, and the product fragrance evaluation result is unqualified after identification by professional perfumers. The main reasons are that there is no second reaction zone 4, the conversion of dehydrolinalool is incomplete, and there are intermediate impurities such as linalool and dihydrolinalool, which affect the product purity and product fragrance index.

[0099] Comparative Example 3 (S3*) uses the tetrahydrolinalool preparation device used in Example 1, except that: no product heat transfer zone is used, and other conditions are consistent with Example 1.

[0100] The experimental results show that the conversion rate of the reaction is above 95%, the selectivity is below 98%, the pressure drop of the tetrahydrolinalool preparation device is 8kPa, the product meets the purity but cannot meet the index requirements, and the product fragrance evaluation result is unqualified after identification by professional perfumers. The main reason is that there is no product heat transfer zone for slow heating. The reaction liquid is directly mixed with the product and enters the second bed reaction zone. In the initial stage of the second reaction zone 4, the reaction is more intense, the temperature rise is higher, and some impurities in the product affect the purity and aroma of the product.

[0101] Comparative Example 4 (S4*) uses the tetrahydrolinalool preparation device used in Example 1, except that the mixer 6 is not used, and other conditions are consistent with Example 1.

[0102] The experimental results show that: the conversion rate of the reaction is 100%, the selectivity is below 98%, the pressure drop of the tetrahydrolinalool preparation device is 8kPa, the product meets the purity but cannot meet the index requirements, and the product fragrance evaluation result is unqualified after identification by professional perfumers. The main reason is that the product and the reaction liquid are not fully mixed, and the reaction liquid has a problem of excessive local concentration during the reaction process, resulting in local hot spots or local high temperatures in the second reaction zone 4, and the reaction impurities are high, which affects the purity and fragrance of the product.

[0103]

[0104] Table 1

[0105]

[0106] Table 2

[0107]

[0108] Table 3

[0109] Although the embodiments of the present application are described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present application, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A tetrahydrolinalool preparation device, characterized in that, include: The shell (1) is provided with a feed end (2), a first reaction zone (3), a second reaction zone (4) and a discharge end (5) in sequence along a first direction (X), wherein the feed end (2) is suitable for introducing raw materials and hydrogen into the first reaction zone (3), and the discharge end (5) is suitable for discharging products; The first reaction zone (3) comprises a heat exchange tube (3001), a catalyst is arranged in the heat exchange tube (3001), two ends of the heat exchange tube (3001) are respectively connected to the feed end (2) and the second reaction zone (4), the first reaction zone (3) is provided with a baffle assembly (7), the baffle assembly (7) separates the first reaction zone (3) into a first cavity (3002) and a second cavity (3003) distributed along the first direction (X), and the second cavity (3003) is connected to the second reaction zone (4); The second reaction zone (4) is connected to the discharge end (5), and the discharge end (5) is connected to the second cavity (3003) through a return pipeline system.

2. The tetrahydrolinalool preparation device according to claim 1, characterized in that The discharge end (5) comprises: The liquid outlet (5001) and the gas outlet (5002) are both connected to the inner cavity of the shell (1), and the liquid outlet (5001) and the gas outlet (5002) are arranged in sequence along the first direction (X), the gas outlet (5002) is suitable for discharging hydrogen, and the liquid outlet (5001) is suitable for discharging products, the first end of the return pipeline system is connected to the liquid outlet (5001), and the second end of the return pipeline system is connected to the second cavity (3003).

3. The tetrahydrolinalool preparation device according to claim 1, characterized in that, The feed end (2) comprises: a feed port (2001) and an air inlet (2002), wherein the feed port (2001) is in communication with the inner cavity of the shell (1), and the feed port (2001) is suitable for introducing raw materials into the inner cavity of the heat exchange tube (3001); and the air inlet (2002) is in communication with the inner cavity of the shell (1), and the air inlet (2002) is suitable for introducing hydrogen into the inner cavity of the heat exchange tube (3001); A gas distributor (2003) is arranged in the shell (1) and is connected to the gas inlet (2002).

4. The tetrahydrolinalool preparation device according to claim 1, wherein Also includes: The mixer (6) is arranged between the heat exchange tube (3001) and the second reaction zone (4), the first end of the mixer (6) is connected to the inner cavity of the heat exchange tube (3001) and the second cavity (3003), the second end of the mixer (6) is connected to the second reaction zone (4), and the second reaction zone (4) is connected to the discharge end (5).

5. The tetrahydrolinalool preparation device according to claim 1, characterized in that, The diameter of the heat exchange tube (3001) is A, wherein 19 mm ≤ A ≤ 80 mm, the length of the heat exchange tube (3001) is B, wherein 2000 mm ≤ B ≤ 6000 mm, and the length ratio of the first cavity (3002) to the second cavity (3003) is C, wherein 2:1 ≤ C ≤ 3:

1.

6. The preparation device according to claim 1, characterized in that: The diameter of the second reaction zone (4) is D, wherein 500 mm ≤ D ≤ 4000 mm, and the length of the second reaction zone (4) is E, wherein 2000 mm ≤ E ≤ 4000 mm.

7. A method for preparing tetrahydrolinalool, comprising preparing tetrahydrolinalool using the tetrahydrolinalool preparation device according to any one of claims 1 to 6, characterized in that: include: Hydrogen and raw materials are introduced into the heat exchange tube (3001) through the feed end (2), and catalytically react with the catalyst in the heat exchange tube (3001) to form a reaction liquid; A cooling medium is introduced into the first cavity (3002) to exchange heat with the heat exchange tube (3001) located in the first cavity (3002); a product is introduced into the second cavity (3003) through the return pipe system to exchange heat with the heat exchange tube (3001) located in the second cavity (3003); The reaction liquid in the heat exchange tube (3001) and the product introduced into the second cavity (3003) through the return pipeline system enter the second reaction zone (4) together for adiabatic reaction to obtain the product; The product produced in the second reaction zone (4) enters the return pipeline system and is passed into the second cavity (3003) for circulation.

8. The method for preparing tetrahydrolinalool according to claim 7, wherein The obtained product is tetrahydrolinalool, the raw material is dehydrolinalool, and tetrahydrolinalool is also introduced into the feed end (2), the ratio of the introduced tetrahydrolinalool to the introduced dehydrolinalool is F, wherein 0:1≤F≤2:1, and the mass ratio of the product introduced into the second cavity (3003) through the return pipeline system to the reaction liquid in the heat exchange tube (3001) is G, wherein 5:1≤G≤20:

1.

9. The method for preparing tetrahydrolinalool according to claim 7, wherein The temperature of the heat exchange tube (3001) located in the first cavity (3002) is H, wherein 30°C≤H≤70°C, the temperature of the heat exchange tube (3001) located in the second cavity (3003) is I, wherein 50°C≤I≤110°C, and the temperature of the second reaction zone (4) is J, wherein 90°C≤J≤150°C.

10. The method for preparing tetrahydrolinalool according to claim 8, wherein The feed flow rate of dehydrolinalool is K, wherein 400 kg / h≤K≤10000 kg / h, and the feed flow rate of hydrogen is L, wherein K≤L≤3K.

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