Reaction apparatus and use thereof

Abstract

This invention provides a reaction apparatus and its application. The reaction apparatus includes a feed pump, a reaction coil, a cooling coil, a back pressure valve, and a reaction liquid receiving device connected in sequence. Using the reaction apparatus provided by this invention can reduce the occurrence of side reactions during the reaction process, while avoiding abnormal fluctuations in temperature and concentration, preventing runaway temperatures and overheating, ensuring a safe and controllable reaction process, and enabling continuous production. Furthermore, the reaction apparatus of this invention occupies significantly less space than conventional equipment, improving the utilization rate of production space.

Description

Technical Field

[0001] This invention belongs to the field of chemical engineering technology and relates to a reaction device and its application, specifically a continuous flow reaction device and its application. Background Technology

[0002] Decarboxylation is an important class of reactions in organic chemistry, involving the removal of carboxyl groups from organic compounds in the form of carbon dioxide or carbonate ions. These reactions have wide applications in chemical engineering, biology, medicine, food science, and other fields.

[0003] Traditional decarboxylation processes mainly include thermochemical decarboxylation, photo-electrochemical decarboxylation, and catalytic decarboxylation. Thermochemical decarboxylation does not require a special catalyst and is carried out under heating, alkaline conditions, or a combination of both; however, this method typically requires high temperatures, which may lead to side reactions and product decomposition, limiting its application in heat-sensitive compounds. Photo-electrochemical decarboxylation utilizes specific reagents to generate an active intermediate from a carboxylic acid, followed by photolysis and reductive decarboxylation in the presence of a suitable reducing agent to obtain the corresponding hydrocarbon. While this method offers mild conditions and high yields, it requires specific equipment and conditions, limiting its feasibility for industrial-scale application. Catalytic decarboxylation processes require the use of transition metals such as copper, silver, and palladium, resulting in expensive catalysts and challenges related to catalyst selection and recovery.

[0004] In addition, the equipment used in the above methods is a conventional reactor or other conventional reaction equipment; the following problems exist in the reaction process: (1) irritating gases are generated during the reaction, causing environmental pollution; (2) the temperature of the reaction liquid is high, the ambient temperature is high, the temperature of the discharged liquid is high, and the safety is poor; (3) conventional equipment occupies a large space.

[0005] In summary, traditional decarboxylation reaction processes and equipment have limitations in terms of efficiency, safety, and cost. Therefore, it is necessary to provide an improved decarboxylation reaction apparatus and method to solve the problems in the existing technology and improve the efficiency and safety of the decarboxylation reaction. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the present invention aims to provide a reaction apparatus and its application. The reaction apparatus provided by the present invention can reduce the occurrence of side reactions during the reaction process, while avoiding abnormal fluctuations in temperature and concentration, preventing runaway temperatures and overheating, ensuring a safe and controllable reaction process, and enabling continuous production. Furthermore, the reaction apparatus of the present invention occupies significantly less space than conventional equipment, improving the utilization rate of production space.

[0007] To achieve this objective, the present invention adopts the following technical solution:

[0008] In a first aspect, the present invention provides a reaction apparatus, the reaction apparatus comprising a feed pump, a reaction coil, a cooling coil, a back pressure valve, and a reaction liquid receiving device, which are sequentially connected via a delivery pipeline.

[0009] The reaction apparatus described in this invention is approximately a closed device, which can reduce the reaction of related side reactions during the reaction process, thereby improving the reaction conversion rate and yield. In addition, the reaction apparatus provided by this invention can avoid abnormal fluctuations in temperature and concentration during the reaction process, avoid the occurrence of temperature runaway and overheating, make the reaction process safe and controllable, and enable continuous production. At the same time, the reaction apparatus provided by this invention occupies far less space than traditional conventional equipment, which can improve the utilization rate of production space.

[0010] As a preferred embodiment of the present invention, the feed pump is selected from any one of a plunger pump, a diaphragm pump, or a peristaltic pump, preferably a plunger pump or a diaphragm pump.

[0011] Preferably, the materials of the reaction coil and the cooling coil are independently selected from any one of stainless steel 316L, Monel alloy, Hastelloy alloy or silicon carbide, with Hastelloy alloy being preferred.

[0012] It is worth noting that the materials of the reaction coil and cooling coil described in this invention, especially Hastelloy, have excellent acid and alkali resistance, thereby improving the service life of the reaction device.

[0013] As a preferred embodiment of the present invention, the inner diameter of the conveying pipeline, the reaction coil and the cooling coil are all 0.1 to 20 mm, for example, 0.1 mm, 1 mm, 5 mm, 8 mm, 11 mm, 14 mm, 17 mm or 20 mm, but not limited to the listed values, and other unlisted values ​​within the range are also applicable; preferably 6 mm.

[0014] The reaction device described in this invention is a microchannel reaction device, wherein the inner diameter of the delivery pipeline, reaction coil and cooling coil is 0.1 to 20 mm. If the inner diameter is too large, cavities may easily be generated in the pipeline during the operation of the equipment, which will lead to unstable pressure in the pipeline and risk of pressure loss.

[0015] Secondly, the present invention provides an application of the reaction apparatus as described in the first aspect, wherein a decarboxylation reaction can be performed using the reaction apparatus.

[0016] Preferably, the decarboxylation reaction includes a continuous flow decarboxylation reaction.

[0017] As a preferred embodiment of the present invention, the continuous flow decarboxylation reaction includes the following steps:

[0018] (1) Mix the organic reactants and solvent to obtain a mixed organic solution;

[0019] (2) The mixed organic solvent obtained in step (1) is transported to the reaction coil for the first reaction by a feed pump, and then kept warm and flowed to the cooling coil for the second reaction. After pressure control by the back pressure valve, the product is collected into the reaction liquid receiving device.

[0020] As a preferred embodiment of the present invention, the structural formula of the organic reactant in step (1) is:

[0021]

[0022] Wherein, R1 and R2 are independently selected from C1 to C12 straight-chain or branched alkyl groups, Any one or more non-adjacent -CH2- groups of the C1-C12 straight-chain or branched alkyl groups can be independently substituted by -C=C-, -C≡C-, -O-, -CO-, -CO-O-, or -O-CO-, and the C1-C12 straight-chain or branched alkyl groups... The -H in the formula can be replaced independently by -F or -Cl.

[0023] More specifically, the synthesis process of the continuous flow decarboxylation reaction described in this invention is as follows:

[0024]

[0025] In this invention, the purpose of mixing the solvent before the decarboxylation reaction in the reaction apparatus is to dissolve the raw materials, allowing them to flow and react within the equipment pipelines; and then the decarboxylation reaction can be completed through a simple heating reaction.

[0026] Preferably, the solvent in step (1) is selected from any one or a combination of at least two of toluene, chlorobenzene, xylene, dichlorobenzene, acetonitrile, dioxane, γ-valerolactone, δ-valerolactone, ethyl benzoate, dipropylene glycol dimethyl ether, or decahydronaphthalene. Typical non-limiting combinations include: a combination of toluene or xylene, a combination of chlorobenzene and dichlorobenzene, a combination of γ-valerolactone, δ-valerolactone, and ethyl benzoate, a combination of toluene, chlorobenzene, xylene, and dichlorobenzene, or a combination of dioxane, dipropylene glycol dimethyl ether, and decahydronaphthalene; preferably dioxane.

[0027] It is worth noting that, for the organic reactants described in this invention, the solvent described in this invention has excellent solubility for the raw materials and does not participate in the reaction itself. When mixed with the reactants, it can reduce the viscosity of the mixed organic solution, thereby making the mixed organic solution have excellent fluidity in the reaction device, further improving the reaction efficiency of the decarboxylation reaction and reducing the generation of by-products.

[0028] In addition, the solvent described in this invention will not react with the product, and excess solvent in the decarboxylation reaction can be removed by distillation or other methods.

[0029] Preferably, the volume ratio of the organic reactant to the solvent in step (1) is 1:1 to 20, for example, it can be 1:1, 1:4, 1:8, 1:12, 1:16 or 1:20, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0030] As a preferred technical solution of the present invention, the pumping speed of the feed pump in step (2) is 1 to 1000 mL / min, for example, it can be 1 mL / min, 10 mL / min, 100 mL / min, 200 mL / min, 400 mL / min, 600 mL / min, 800 mL / min or 1000 mL / min, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable; preferably 200 mL / min.

[0031] This invention optimizes the pumping rate of the mixed organic solution in the decarboxylation reaction to control the reaction efficiency and improve the decarboxylation reaction efficiency. If the pumping rate is too slow, it will lead to excessively long reaction time, more side reactions, and even product carbonization, which may also affect the service life of the reaction device. If the pumping rate is too fast, it will lead to incomplete reaction and thus affect the decarboxylation reaction efficiency.

[0032] As a preferred technical solution of the present invention, the temperature of the first reaction in step (2) is 200 to 500°C, for example, it can be 200°C, 250°C, 300°C, 350°C, 400°C, 450°C or 500°C, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable; preferably 255 to 260°C.

[0033] Preferably, the temperature of the second reaction in step (2) is 0 to 100°C, for example, it can be 0°C, 10°C, 20°C, 40°C, 60°C, 80°C or 100°C, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable; preferably 40 to 50°C.

[0034] In this invention, the decarboxylation reaction is effectively carried out through the first reaction. If the reaction temperature is too high, it will lead to an increase in side reactions during the reaction process, or even lead to carbonization of the product. If the reaction temperature is too low, it will lead to a slow reaction rate or no reaction, thereby reducing the reaction efficiency.

[0035] The present invention achieves cooling of the decarboxylation reaction solution obtained from the first reaction through the second reaction; if the reaction temperature is too high, the temperature of the reaction liquid will be high, which may cause safety risks such as burns; if the reaction temperature is too low, the product will precipitate out of the material, resulting in blockage of the pipeline.

[0036] Preferably, the heat preservation flow time in step (2) is 1 to 120 min, for example, it can be 1 min, 10 min, 20 min, 40 min, 60 min, 80 min, 100 min or 120 min, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable; preferably 40 min.

[0037] In this invention,

[0038] The pressure of the pressure control process in step (2) is 0.1 to 10 MPa, for example, it can be 0.1 MPa, 1 MPa, 2 MPa, 4 MPa, 6 MPa, 8 MPa or 10 MPa, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable; preferably 3 to 3.5 MPa.

[0039] The purpose of this invention in controlling the output pressure of the reaction products is to control the reaction pressure, keep the pressure load of the reaction device within a safe range, and reduce safety risks.

[0040] As a preferred embodiment of the present invention, the structural formula of the product described in step (2) is as follows:

[0041]

[0042] Wherein, R1 and R2 are independently selected from C1 to C12 straight-chain or branched alkyl groups, Any one or more non-adjacent -CH2- groups of the C1-C12 straight-chain or branched alkyl groups can be independently substituted by -C=C-, -C≡C-, -O-, -CO-, -CO-O-, or -O-CO-, and the C1-C12 straight-chain or branched alkyl groups... The -H in the formula can be replaced independently by -F or -Cl.

[0043] It is worth noting that the pretreatment of the reaction device is also included before the feeding pump is used to transport the mixed organic solvent in step (2) of the present invention.

[0044] Preferably, the pretreatment specifically includes the following operations: firstly, solvent is pumped into the reaction device through a feed pump, and the back pressure valve is adjusted to control the pressure, and the temperature of the reaction coil and the cooling coil is set; and during the heating process, solvent is pumped in through a feed pump in a circulating manner.

[0045] In addition, in this invention, after the mixing of organic solvents in step (1) is completed, an appropriate amount of solvent is continued to be pumped in through the feed pump to replace the reaction liquid in the reaction coil and the cooling coil.

[0046] As a preferred embodiment of the present invention, the continuous flow decarboxylation reaction performed using the reaction apparatus described in the first aspect of the present invention, as provided in the second aspect of the present invention, includes the following steps:

[0047] (1) Mix the organic reactants and solvent to obtain a mixed organic solution;

[0048] The solvent is selected from any one or a combination of at least two of toluene, chlorobenzene, xylene, dichlorobenzene, acetonitrile, dioxane, γ-valerolactone, δ-valerolactone, ethyl benzoate, dipropylene glycol dimethyl ether, or decahydronaphthalene.

[0049] (2) The mixed organic solvent obtained in step (1) is pumped into the reaction coil at a pumping rate of 1 to 1000 mL / min using a feed pump. After the first reaction is carried out at 200 to 500 °C, the mixture is kept warm and flowed for 1 to 120 min before being transferred to the cooling coil for the second reaction at 0 to 100 °C. Then, the pressure is controlled by a back pressure valve until the pressure is 0.1 to 10 MPa, and the product is collected into the reaction liquid receiving device.

[0050] The numerical range described in this invention includes not only the point values ​​listed above, but also any point values ​​within the numerical ranges not listed above. Due to space limitations and for the sake of brevity, this invention will not exhaustively list all the specific point values ​​included in the range.

[0051] Compared with the prior art, the present invention has the following beneficial effects:

[0052] (1) The reaction apparatus provided by the present invention enables the decarboxylation reaction to be safe and controllable, realizes continuous production, and reduces the pollution of the environment by reaction byproducts during the production process;

[0053] (2) The reaction device provided by the present invention occupies far less space than conventional equipment, thus improving the utilization rate of production space;

[0054] (3) The reaction apparatus provided by the present invention can reduce the post-processing temperature, thereby improving safety. Attached Figure Description

[0055] Figure 1 This is a structural diagram of the reaction apparatus described in this invention;

[0056] Among them, 1 is the feed pump, 2 is the reaction coil, 3 is the cooling coil, 4 is the back pressure valve, and 5 is the reaction liquid receiving device. Detailed Implementation

[0057] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0058] In one specific embodiment, the present invention provides a reaction apparatus, such as... Figure 1 As shown, the reaction apparatus includes a feed pump 1, a reaction coil 2, a cooling coil 3, a back pressure valve 4, and a reaction liquid receiving device 5, which are connected in sequence through a delivery pipeline.

[0059] The feed pump 1 is selected from any one of a plunger pump, a diaphragm pump, or a peristaltic pump; the materials of the reaction coil 2 and the cooling coil 3 are independently selected from any one of stainless steel 316L, Monel alloy, Hastelloy alloy, or silicon carbide; the inner diameter of the conveying pipeline, the reaction coil 2, and the cooling coil 3 is 0.1 to 20 mm.

[0060] In another specific embodiment, the present invention provides a continuous flow decarboxylation reaction using the above-described reaction apparatus, the continuous flow decarboxylation reaction comprising the following steps:

[0061] (1) Mix the organic reactants and solvent to obtain a mixed organic solution;

[0062] The solvent is selected from any one or a combination of at least two of toluene, chlorobenzene, xylene, dichlorobenzene, acetonitrile, dioxane, γ-valerolactone, δ-valerolactone, ethyl benzoate, dipropylene glycol dimethyl ether, or decahydronaphthalene.

[0063] (2) First, the solvent is pumped into the reaction device at a pumping rate of 1 to 1000 mL / min using the feed pump 1, and the back pressure valve 4 is adjusted to control the pressure to 0.1 to 10 MPa. The temperatures of the reaction coil 2 and the cooling coil 3 are set to 200 to 500 °C and 0 to 100 °C, respectively. During the heating process, the solvent is pumped into the reaction device through the feed pump 1 in a circulating manner.

[0064] After the temperature of the reaction coil 2 and the cooling coil 3 reaches the set temperature, the mixed organic solvent obtained in step (1) is continuously pumped to the reaction coil 2 at a pumping rate of 1 to 1000 mL / min using the feed pump 1. After the first reaction is carried out at 200 to 500°C, the mixture is kept warm and flowed for 1 to 120 minutes before being transferred to the cooling coil 3 for the second reaction at 0 to 100°C. Then, the pressure is controlled by the back pressure valve 4 until the pressure is 0.1 to 10 MPa, and the product is collected into the reaction liquid receiving device 5.

[0065] Finally, after the mixed organic solvent pump in step (1) is completed, continue to pump an appropriate amount of solvent through the feed pump 1 to replace the reaction liquid in the reaction coil 2 and the cooling coil 3.

[0066] Example 1

[0067] This embodiment provides a reaction apparatus, such as... Figure 1As shown, the reaction apparatus includes a feed pump 1, a reaction coil 2, a cooling coil 3, a back pressure valve 4, and a reaction liquid receiving device 5, which are connected in sequence through a delivery pipeline.

[0068] The feed pump 1 is a peristaltic pump; the reaction coil 2 and the cooling coil 3 are made of Hastelloy alloys; and the inner diameter of the conveying pipeline, the reaction coil 2 and the cooling coil 3 is 6 mm.

[0069] This embodiment also provides a continuous flow decarboxylation reaction using the above-described reaction apparatus, the continuous flow decarboxylation reaction comprising the following steps:

[0070] (1) Mix 2 kg of organic reactant (decane-1,8,8-tricarboxylic acid) and 10 kg of solvent (dioxane) in a 20 L dissolving tank to obtain a mixed organic solution;

[0071] (2) First, the solvent is pumped into the reaction device at a pumping rate of 200 mL / min using the feed pump 1, and the back pressure valve 4 is adjusted to control the pressure at 3.1 MPa. The temperatures of the reaction coil 2 and the cooling coil 3 are set to 257°C and 50°C, respectively. During the heating process, the solvent is pumped into the reaction device through the feed pump 1 in a circulating manner.

[0072] After the temperature of the reaction coil 2 and the cooling coil 3 reaches the set temperature, the mixed organic solvent obtained in step (1) is continuously pumped to the reaction coil 2 at a pumping speed of 200 mL / min using the feed pump 1. After the first reaction is carried out at 257°C, the mixture is kept warm and flowed for 40 min before being transferred to the cooling coil 3 for the second reaction at 50°C. Then, the pressure is controlled by the back pressure valve 4 until the pressure reaches 3.1 MPa, and the product (2-ethylstigmic acid) is collected into the reaction liquid receiving device 5.

[0073] Finally, after the mixed organic solvent pump in step (1) is completed, continue to pump an appropriate amount of solvent through the feed pump 1 to replace the reaction liquid in the reaction coil 2 and the cooling coil 3.

[0074] The synthesis process of the continuous flow decarboxylation reaction described in this embodiment is as follows:

[0075]

[0076] Example 2

[0077] This embodiment provides a reaction apparatus, such as... Figure 1 As shown, the reaction apparatus includes a feed pump 1, a reaction coil 2, a cooling coil 3, a back pressure valve 4, and a reaction liquid receiving device 5, which are connected in sequence through a delivery pipeline.

[0078] The feed pump 1 is a plunger pump; the reaction coil 2 and the cooling coil 3 are each made of Monel alloy; the inner diameter of the conveying pipeline, the reaction coil 2 and the cooling coil 3 is 1.1 mm.

[0079] This embodiment also provides a continuous flow decarboxylation reaction using the above-described reaction apparatus, the continuous flow decarboxylation reaction comprising the following steps:

[0080] (1) Mix 50g of organic reactant (octane-1,6,6-tricarboxylic acid) and 150g of solvent (γ-valerol) in a 1L beaker and dissolve at room temperature to obtain a mixed organic solution;

[0081] (2) First, the solvent is pumped into the reaction device at a pumping rate of 1.2 mL / min using the feed pump 1, and the back pressure valve 4 is adjusted to control the pressure to 1 MPa. The temperatures of the reaction coil 2 and the cooling coil 3 are set to 255°C and 50°C, respectively. During the heating process, the solvent is pumped into the reaction device through the feed pump 1 in a circulating manner.

[0082] After the temperature of the reaction coil 2 and the cooling coil 3 reaches the set temperature, the mixed organic solvent obtained in step (1) is continuously pumped to the reaction coil 2 at a pumping speed of 1.2 mL / min using the feed pump 1. After the first reaction is carried out at 255°C, the mixture is kept warm and flowed for 50 min before being transferred to the cooling coil 3 for the second reaction at 50°C. Then, the pressure is controlled by the back pressure valve 4 until the pressure is 1 MPa, and the product (2-ethyl octanoic acid) is collected into the reaction liquid receiving device 5.

[0083] Finally, after the mixed organic solvent pump in step (1) is completed, continue to pump an appropriate amount of solvent through the feed pump 1 to replace the reaction liquid in the reaction coil 2 and the cooling coil 3.

[0084] The synthesis process of the continuous flow decarboxylation reaction described in this embodiment is as follows:

[0085]

[0086] Example 3

[0087] This embodiment provides a reaction apparatus, which is the same as that in Embodiment 1.

[0088] This embodiment also provides a continuous flow decarboxylation reaction using the reaction apparatus described in Example 1. The only difference between the continuous flow decarboxylation reaction and that in Example 1 is:

[0089] In this embodiment, the pressure of the pressure control process described in step (2) is adjusted to 10 MPa.

[0090] Example 4

[0091] This embodiment provides a reaction apparatus, which is the same as that in Embodiment 1.

[0092] This embodiment also provides a continuous flow decarboxylation reaction using the reaction apparatus described in Example 1. The only difference between the continuous flow decarboxylation reaction and that in Example 1 is:

[0093] In this embodiment, the pressure of the pressure control process described in step (2) is adjusted to 12 MPa.

[0094] Example 5

[0095] This embodiment provides a reaction apparatus, which is the same as that in Embodiment 1.

[0096] This embodiment also provides a continuous flow decarboxylation reaction using the reaction apparatus described in Example 1. The only difference between the continuous flow decarboxylation reaction and that in Example 1 is:

[0097] In this embodiment, the pumping speed of the mixed organic solvent in step (2) is adjusted to 1000 mL / min.

[0098] Example 6

[0099] This embodiment provides a reaction apparatus, which is the same as that in Embodiment 1.

[0100] This embodiment also provides a continuous flow decarboxylation reaction using the reaction apparatus described in Example 1. The only difference between the continuous flow decarboxylation reaction and that in Example 1 is:

[0101] In this embodiment, the pumping speed of the mixed organic solvent in step (2) is adjusted to 1200 mL / min.

[0102] Example 7

[0103] The embodiment provides a reaction apparatus that is the same as that in Embodiment 1.

[0104] This embodiment also provides a continuous flow decarboxylation reaction using the reaction apparatus described in Example 1. The only difference between the continuous flow decarboxylation reaction and that in Example 1 is:

[0105] In this embodiment, the temperature of the first reaction in step (2) is adjusted to 150°C.

[0106] Example 8

[0107] The embodiment provides a reaction apparatus that is the same as that in Embodiment 1.

[0108] This embodiment also provides a continuous flow decarboxylation reaction using the reaction apparatus described in Example 1. The only difference between the continuous flow decarboxylation reaction and that in Example 1 is:

[0109] In this embodiment, the temperature of the first reaction in step (2) is adjusted to 520°C.

[0110] Example 9

[0111] The embodiment provides a reaction apparatus that is the same as that in Embodiment 1.

[0112] This embodiment also provides a continuous flow decarboxylation reaction using the reaction apparatus described in Example 1. The only difference between the continuous flow decarboxylation reaction and that in Example 1 is:

[0113] In this embodiment, the temperature of the second reaction in step (2) is adjusted to 0°C.

[0114] Example 10

[0115] The embodiment provides a reaction apparatus that is the same as that in Embodiment 1.

[0116] This embodiment also provides a continuous flow decarboxylation reaction using the reaction apparatus described in Example 1. The only difference between the continuous flow decarboxylation reaction and that in Example 1 is:

[0117] In this embodiment, the temperature of the second reaction in step (2) is adjusted to 100°C.

[0118] Example 11

[0119] The embodiment provides a reaction apparatus that is the same as that in Embodiment 1.

[0120] This embodiment also provides a continuous flow decarboxylation reaction using the reaction apparatus described in Example 1. The only difference between the continuous flow decarboxylation reaction and that in Example 1 is:

[0121] In this embodiment, the temperature of the second reaction in step (2) is adjusted to 110°C.

[0122] Example 12

[0123] The embodiment provides a reaction apparatus that is the same as that in Embodiment 1.

[0124] This embodiment also provides a continuous flow decarboxylation reaction using the reaction apparatus described in Example 1. The only difference between the continuous flow decarboxylation reaction and that in Example 1 is:

[0125] This embodiment omits the solvent mixing process described in step (1).

[0126] Example 13

[0127] The embodiment provides a reaction apparatus, which differs from that of Embodiment 1 only in that:

[0128] In this embodiment, the inner diameter of the reaction coil 2 and the cooling coil 3 is adjusted to 20mm.

[0129] This embodiment also provides a continuous flow decarboxylation reaction using the above-described reaction apparatus, which is the same as in Example 1.

[0130] Example 14

[0131] The embodiment provides a reaction apparatus, which differs from that of Embodiment 1 only in that:

[0132] In this embodiment, the inner diameters of the reaction coil 2 and the cooling coil 3 are adjusted to 25mm.

[0133] This embodiment also provides a continuous flow decarboxylation reaction using the above-described reaction apparatus, which is the same as in Example 1.

[0134] Example 15

[0135] This embodiment provides a reaction apparatus, which differs from that of Embodiment 1 only in that:

[0136] In this embodiment, the materials of the reaction coil 2 and the cooling coil 3 are adjusted to carbon manganese steel.

[0137] This embodiment also provides a continuous flow decarboxylation reaction using the above-described reaction apparatus, which is the same as in Example 1.

[0138] Comparative Example 1

[0139] This comparative example provides a reaction apparatus, which differs from that of Example 1 only in that:

[0140] In this comparative example, the reaction coil 2 is modified into a reaction vessel.

[0141] This comparative example also provides a continuous flow decarboxylation reaction using the above-described reaction apparatus, which is the same as in Example 1.

[0142] Comparative Example 2

[0143] This comparative example provides a reaction apparatus, which differs from that of Example 1 only in that:

[0144] This comparative example omits the installation of the cooling coil 3.

[0145] This comparative example also provides a continuous flow decarboxylation reaction using the above-described reaction apparatus, which is the same as in Example 1.

[0146] Comparative Example 3

[0147] This comparative example provides a reaction apparatus, which differs from that of Example 1 only in that:

[0148] The configuration of the reaction coil 2 is omitted in this comparative example.

[0149] This comparative example also provides a continuous flow decarboxylation reaction using the above-described reaction apparatus, which is the same as in Example 1.

[0150] Comparative Example 4

[0151] This comparative example provides a reaction apparatus, which differs from that of Example 1 only in that:

[0152] This comparative example omits the back pressure valve 4.

[0153] This comparative example also provides a continuous flow decarboxylation reaction using the above-described reaction apparatus, which is the same as in Example 1.

[0154] The products obtained from the continuous flow decarboxylation reaction using the reaction apparatus provided in the above embodiments and comparative examples were distilled, weighed, and their yields were calculated. The purity of the products was detected by gas chromatography, and the results are shown in Table 1.

[0155] In addition, the state monitoring of the reaction apparatus provided using the above embodiments and comparative examples is shown in Table 1.

[0156] Table 1

[0157]

[0158]

[0159] According to Table 1,

[0160] (1) Comprehensive analysis of Examples 1 and 2 shows that the reaction device provided by the present invention can improve the yield of decarboxylation reaction and the purity of product; and the reaction process is safe and controllable, realizing continuous production, and reducing the pollution of the environment by reaction byproducts during the production process.

[0161] (2) A comprehensive analysis of Examples 1 and 3-11 shows that the selection of process parameters in the decarboxylation reaction can affect the product yield or purity;

[0162] When the pressure of the pressure control process is too high, it will lead to an increase in the pressure load of the reaction device, a decrease in safety, and a liquid output that is far lower than the set flow rate. When the pressure is too low, it will cause the equipment to spray material.

[0163] When the pumping rate of the mixed organic solvent is too high, the reaction time of the mixed organic solution in the reaction coil will be too short, resulting in incomplete reaction and residual raw materials. When the pumping rate is too low, the product will react excessively, thereby increasing the production of by-products and reducing the purity of the obtained product.

[0164] In addition, when the pumping speed is 1000 mL / min (as in Example 5) and the tube diameter is 6 mm, the reaction time will be shortened, which will lead to a decrease in yield. If the tube diameter of the reaction device is appropriately increased, the yield will be further improved. Therefore, reasonable control of tube diameter and pumping speed is one of the important factors affecting yield.

[0165] When the temperature of the first reaction is too high, it will cause the product to react excessively, resulting in a larger amount of by-products and a decrease in product purity; when the temperature is too low, it will cause the reaction to be slow or not to react at all.

[0166] When the temperature of the second reaction is too high, it will lead to a high liquid temperature, which may cause the material to spray out or cause burns; if the temperature is too low, solids will precipitate out.

[0167] (3) Comprehensive analysis of Examples 1 and 12 shows that the addition of solvent will help the raw materials to flow and react well in the high-temperature continuous flow equipment;

[0168] (4) A comprehensive analysis of Examples 1 and 13-15 shows that the selection of equipment (size or material) in the reaction apparatus affects the reaction efficiency of the decarboxylation reaction;

[0169] When the inner diameter of the reaction coil 2 and the cooling coil 3 is too large, the liquid discharge process will be interrupted and there will be a loss of pressure. Conversely, when the inner diameter of the reaction coil 2 and the cooling coil 3 is too small, the liquid discharge will be small and it will be easy to get clogged.

[0170] When the reaction coil 2 and cooling coil 3 are made of carbon manganese steel, corrosion of the pipes will occur.

[0171] (5) A comprehensive analysis of Example 1 and Comparative Examples 1-4 shows that the connection method or equipment of the reaction apparatus can affect the decarboxylation reaction;

[0172] When reaction coil 2 is adjusted to a reaction vessel, the decarboxylation reaction becomes a discontinuous flow reaction. More specifically, the decarboxylation reaction becomes uneven, with some parts reacting excessively and others not reacting.

[0173] Omitting the reaction coil will cause the reaction liquid outlet temperature to be too high, which will cause the equipment to spray material.

[0174] When the cooling coil is omitted, the mixed organic solution skips the first reaction and proceeds directly to the second reaction. However, the set temperature of the second reaction cannot achieve the decarboxylation reaction, resulting in the raw materials not reacting.

[0175] When the back pressure valve is omitted, the pressure cannot be controlled when the product flows out, which in turn causes the reaction device to be unable to maintain pressure, and the equipment is very likely to spray material.

[0176] In summary, the reaction apparatus provided by this invention can reduce the occurrence of side reactions during the reaction process, avoid abnormal fluctuations in temperature and concentration, prevent runaway and overheating, ensure the safety and controllability of the reaction process, and enable continuous production. In addition, the reaction apparatus described in this invention occupies far less space than conventional equipment, thus improving the utilization rate of production space.

[0177] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A reaction apparatus, characterized in that, The reaction apparatus includes a feed pump, a reaction coil, a cooling coil, a back pressure valve, and a reaction liquid receiving device, which are connected in sequence through a delivery pipeline.

2. The reaction apparatus according to claim 1, characterized in that, The feed pump is selected from any one of a plunger pump, a diaphragm pump, or a peristaltic pump, preferably a plunger pump or a diaphragm pump. Preferably, the materials of the reaction coil and the cooling coil are independently selected from any one of stainless steel 316L, Monel alloy, Hastelloy alloy or silicon carbide, with Hastelloy alloy being preferred.

3. The reaction apparatus according to claim 1 or 2, characterized in that, The inner diameter of the conveying pipeline, reaction coil, and cooling coil is 0.1–20 mm, preferably 6 mm.

4. An application of the reaction apparatus as described in any one of claims 1-3, characterized in that, The decarboxylation reaction is carried out using the aforementioned reaction apparatus; The decarboxylation reaction includes a continuous flow decarboxylation reaction.

5. The application according to claim 4, characterized in that, The continuous flow decarboxylation reaction includes the following steps: (1) Mix the organic reactants and solvent to obtain a mixed organic solution; (2) The mixed organic solvent obtained in step (1) is transported to the reaction coil for the first reaction by a feed pump, and then kept warm and flowed to the cooling coil for the second reaction. After pressure control by the back pressure valve, the product is collected into the reaction liquid receiving device.

6. The application according to claim 5, characterized in that, The structural formula of the organic reactant in step (1) is: Wherein, R1 and R2 are independently selected from C1 to C12 straight-chain or branched alkyl groups, Any one or more non-adjacent -CH2- groups of the C1-C12 straight-chain or branched alkyl groups can be independently substituted by -C=C-, -C≡C-, -O-, -CO-, -CO-O-, or -O-CO-, and the C1-C12 straight-chain or branched alkyl groups... The -H in the formula can be replaced independently by -F or -Cl; Preferably, the solvent in step (1) is selected from any one or a combination of at least two of toluene, chlorobenzene, xylene, dichlorobenzene, acetonitrile, dioxane, γ-valerolactone, δ-valerolactone, ethyl benzoate, dipropylene glycol dimethyl ether or decahydronaphthalene, with dioxane being the most preferred; Preferably, the volume ratio of the organic reactant to the solvent in step (1) is 1:1 to 20.

7. The application according to claim 5 or 6, characterized in that, The pumping speed of the feed pump in step (2) is 1 to 1000 mL / min, preferably 200 mL / min.

8. The application according to any one of claims 5-7, characterized in that, In step (2), the temperature of the first reaction is 200–500°C, preferably 255–260°C; Preferably, the heat preservation flow time in step (2) is 1 to 120 minutes, preferably 40 minutes; Preferably, the temperature of the second reaction in step (2) is 0–100°C, more preferably 40–50°C; The pressure of the pressure control process in step (2) is 0.1 to 10 MPa, preferably 3 to 3.5 MPa.

9. The application according to any one of claims 5-8, characterized in that, The structural formula of the product in step (2) is as follows: Wherein, R1 and R2 are independently selected from C1 to C12 straight-chain or branched alkyl groups, Any one or more non-adjacent -CH2- groups of the C1-C12 straight-chain or branched alkyl groups can be independently substituted by -C=C-, -C≡C-, -O-, -CO-, -CO-O-, or -O-CO-, and the C1-C12 straight-chain or branched alkyl groups... The -H in the formula can be replaced independently by -F or -Cl.

10. The application according to any one of claims 5-9, characterized in that, The continuous flow decarboxylation reaction includes the following steps: (1) Mix the organic reactants and solvent in a volume ratio of 1:1 to 20 to obtain a mixed organic solution; The solvent is selected from any one or a combination of at least two of toluene, chlorobenzene, xylene, dichlorobenzene, acetonitrile, dioxane, γ-valerolactone, δ-valerolactone, ethyl benzoate, dipropylene glycol dimethyl ether, or decahydronaphthalene. (2) The mixed organic solvent obtained in step (1) is pumped into the reaction coil at a pumping rate of 1 to 1000 mL / min using a feed pump. After the first reaction is carried out at 200 to 500 °C, the mixture is kept warm and flowed for 1 to 120 min before being transferred to the cooling coil for the second reaction at 0 to 100 °C. Then, the pressure is controlled by a back pressure valve until the pressure is 0.1 to 10 MPa, and the product is collected into the reaction liquid receiving device.

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