Continuous device for preparing lipoic acid

Abstract

The utility model provides a continuous device for preparing lipoic acid. The continuous device comprises a continuous feeding device, wherein reaction raw materials are stored in the continuous feeding device; a feeding hole of the continuous reaction device is communicated with a discharging hole of the continuous feeding device so as to generate a continuous reaction product; a feed port of the continuous concentration and liquid separation device is communicated with a discharge port of the continuous reaction device so as to perform continuous concentration and liquid separation on the continuous reaction product to obtain a concentrated liquid separation product; a feeding hole of the continuous hydrolysis and dilution device is communicated with a discharging hole of the continuous concentration and liquid separation device so as to carry out continuous hydrolysis and dilution on the concentration and liquid separation product to obtain a hydrolysis and dilution product; a feeding hole of the continuous extraction and crystallization device is communicated with a discharging hole of the continuous hydrolysis and dilution device so as to carry out continuous extraction and crystallization on a hydrolysis and dilution product, and inputting the hydrolysis and dilution product into the continuous post-treatment device for continuous post-treatment to obtain a lipoic acid crude product; the problem of low production efficiency of intermittent production of lipoic acid in the prior art is solved.

Description

Technical Field

[0001] The utility model relates to the technical field of preparing thioctic acid, in particular to a continuous device for preparing thioctic acid. Background Art

[0002] Lipoic acid (CAS#62-46-4, chemical name 1,2-dithiocyclopentyl-3-pentanoic acid, molecular formula C8H14O2S2) can be used as a coenzyme to participate in the acyl transfer in the metabolism of substances in the body, can eliminate free radicals that lead to accelerated aging and disease, and has strong antioxidant capacity. It is currently the only drug that can meet the standard evaluation of antioxidants. It is called a universal antioxidant and belongs to the vitamin class of drugs.

[0003] Lipoic acid is mainly used as a medicine abroad. It enters cells after being absorbed through the intestines. It has the characteristics of both fat solubility and water solubility, and is also widely used as a dietary supplement and cosmetic raw material. In the domestic medical field, it is widely used to prevent and treat diabetes and its related complications. In the field of health care products, it is mainly used to remove free radicals in the body, prevent lipid peroxidation, and protect cells from oxidative damage, so as to achieve the purpose of preventing and assisting in the treatment of diseases.

[0004] Lipoic acid belongs to a class of compounds in the B vitamins. Since the 20th century, people have discovered that lipoic acid is not only an important coenzyme in organisms, but also plays an antioxidant role, which can protect biological tissues and lower blood sugar. In addition, lipoic acid is widely used in organic synthesis reactions as a catalyst or catalyst precursor, and is also used as an additive for rubber antioxidants and rubber processing aids in the materials industry. Structurally, lipoic acid is an eight-carbon fatty acid, in which a five-membered ring is formed by a disulfide bond between C6 and C8. Because the disulfide bond in the molecular structure is unstable, it will cause the disulfide bond in the five-membered ring to break when heated or exposed to light, and it is easy to produce very unstable free radicals. At the same time, the disulfide bond also has the properties of a dynamic covalent bond, so lipoic acid is very easy to interact with other molecules, and react with another molecule of lipoic acid at the position of the disulfide bond to form a polymer of lipoic acid.

[0005] The existing lipoic acid production process is mostly intermittent reaction (that is, the reaction raw materials are put into the reactor at one time for reaction). In the intermittent reaction process, there are disadvantages such as low production efficiency, unstable product quality, and poor safety. Utility Model Content

[0006] The main purpose of the utility model is to provide a continuous device for preparing lipoic acid, so as to solve the problems of low production efficiency in the intermittent production of lipoic acid in the prior art.

[0007] In order to achieve the above object, according to one aspect of the utility model, a continuous device for preparing lipoic acid is provided.

[0008] A continuous feeding device, wherein the reaction raw materials are stored in the continuous feeding device, and the reaction raw materials include sulfide liquid, ethyl 6,8-dichlorooctanoate, sodium sulfite, alkali solution, acid solution and solvent;

[0009] A continuous reaction device, wherein the feed port of the continuous reaction device is connected to the discharge port of the continuous feeding device, so that the reaction raw materials react continuously in the continuous reaction device to generate a continuous reaction product, wherein the continuous reaction product is ethyl lipoate;

[0010] A continuous concentration and liquid separation device, wherein the feed port of the continuous concentration and liquid separation device is connected to the discharge port of the continuous reaction device, so as to continuously concentrate and separate the continuous reaction product to obtain a concentrated liquid separation product;

[0011] A continuous hydrolysis and dilution device, wherein the feed port of the continuous hydrolysis and dilution device is connected to the discharge port of the continuous concentration and liquid separation device to continuously hydrolyze and continuously dilute the concentrated and liquid-separated product to obtain a continuous hydrolysis and dilution product, wherein the continuous hydrolysis and dilution product is a sodium lipoic acid solution;

[0012] A continuous extraction and crystallization device is provided, wherein the feed port of the continuous extraction and crystallization device is connected with the discharge port of the continuous hydrolysis and dilution device to continuously extract and crystallize the hydrolysis and dilution product, and input the product into a continuous post-treatment device for continuous post-treatment to obtain a crude lipoic acid product.

[0013] Further, the continuous feeding device comprises: a sulfide liquid storage tank, in which sulfide liquid is stored, and an outlet of the sulfide liquid storage tank is connected to a first feed port of the continuous reaction device to transport the sulfide liquid to the continuous reaction device;

[0014] A 6,8-dichlorooctanoic acid ethyl ester storage tank, wherein the outlet of the 6,8-dichlorooctanoic acid ethyl ester storage tank is connected to the second feed inlet of the continuous reaction device to transport the 6,8-dichlorooctanoic acid ethyl ester to the continuous reaction device;

[0015] A first solvent storage tank, wherein the outlet of the first solvent storage tank is connected to the third feed inlet of the continuous reaction device so as to transport the first solvent to the continuous reaction device.

[0016] Furthermore, the continuous feeding device also includes:

[0017] A sulfide liquid buffer tank, which is arranged between the sulfide liquid storage tank and the first feed port to continuously transport the sulfide liquid to the continuous reaction device; and / or,

[0018] 6,8-dichlorooctanoic acid ethyl ester buffer tank, the 6,8-dichlorooctanoic acid ethyl ester buffer tank is arranged between the 6,8-dichlorooctanoic acid ethyl ester storage tank and the second feed port, so as to realize continuous delivery of 6,8-dichlorooctanoic acid ethyl ester to the continuous reaction device; and / or,

[0019] The first solvent buffer tank is arranged between the first solvent storage tank and the third feed port to realize continuous delivery of the first solvent to the continuous reaction device.

[0020] Furthermore, the continuous reaction device comprises: a continuous cyclization reaction component, the continuous cyclization reaction component has a first feed inlet, a second feed inlet and a third feed inlet, and the continuous cyclization reaction component has a cyclization reaction site, so that the reaction raw materials undergo a continuous cyclization reaction in the cyclization reaction site;

[0021] a sulfite storage tank, wherein sulfite is stored in the sulfite storage tank;

[0022] a continuous impurity removal reaction component, wherein the inlet of the continuous impurity removal reaction component is connected to the outlet of the continuous cyclization reaction component and the outlet of the sulfite storage tank, respectively, so that the sulfite in the continuous impurity removal reaction component reacts with impurities formed after the continuous cyclization reaction in the continuous cyclization reaction component to obtain a continuous reaction product;

[0023] The sulfite buffer tank is arranged between the sulfite storage tank and the continuous impurity removal reaction component to realize continuous transportation of sulfite to the continuous impurity removal reaction component.

[0024] Furthermore, the continuous concentration and liquid separation device comprises: a continuous liquid separation device, the inlet of which is connected to the continuous impurity removal reaction component, so as to continuously separate the continuous reaction product transported from the continuous impurity removal reaction component to obtain an organic phase and an aqueous phase, and transport the aqueous phase to an aqueous phase storage tank;

[0025] A continuous water washing device, wherein the inlet of the continuous water washing device is connected to the outlet of the continuous liquid separation device, so as to wash the organic phase with water to remove impurities in the organic phase and obtain a water-washed organic phase;

[0026] A continuous concentrating device is connected to the continuous water washing device to continuously concentrate the water-washed organic phase to obtain a concentrated liquid separation product, and the concentrated liquid separation product is a concentrated organic phase.

[0027] Furthermore, the continuous device also includes a continuous mixing component disposed between the continuous concentration and separation device and the continuous hydrolysis and dilution device, and the inlet of the continuous mixing component is connected to the continuous concentration device and the alkali solution storage tank, respectively, so that the alkali solution and the concentrated and separated liquid product are continuously mixed in the continuous mixing component to obtain a continuous mixed product;

[0028] The continuous device also includes an alkali solution buffer tank disposed between the alkali solution storage tank and the continuous mixing component to realize continuous delivery of the alkali solution to the continuous mixing component;

[0029] Among them, the alkali solution is sodium hydroxide solution.

[0030] Further, the continuous hydrolysis and dilution device comprises: a continuous hydrolysis device, the inlet of the continuous hydrolysis device is connected to the outlet of the continuous mixing component to continuously hydrolyze the continuous mixed product to obtain a continuous hydrolysis product;

[0031] A diluent storage tank, wherein the diluent storage tank stores a diluent, and the diluent is water;

[0032] A continuous dilution device, the inlet of which is respectively connected to the outlet of the continuous hydrolyzate and the outlet of the storage tank of the diluent, so as to continuously dilute the continuous hydrolyzate with the diluent to obtain a hydrolyzed diluted product.

[0033] Furthermore, the continuous extraction crystallization device comprises: a second solvent storage tank, in which a second solvent is stored, and the second solvent is any one or more of aliphatic hydrocarbons, aromatic hydrocarbons, alcohols, carboxylic acid esters, amides and heterocyclics;

[0034] A continuous extraction and liquid separation device, the inlet of which is connected to the outlet of the continuous dilution device in the continuous hydrolysis and dilution device and the second solvent storage tank respectively, so as to continuously extract and separate the hydrolysis and dilution products through the second solvent to obtain continuous extraction products, which include a heavy phase and a light phase.

[0035] Furthermore, the continuous extraction crystallization device further comprises: a light phase storage tank, which is connected to the continuous extraction liquid separation device to collect the light phase output from the continuous extraction liquid separation device;

[0036] An acid storage tank, wherein the acid storage tank stores acid, and the acid is hydrochloric acid;

[0037] An acid buffer tank, wherein the inlet end of the acid buffer tank is connected to the outlet end of the acid storage tank;

[0038] The continuous crystallization component has its inlet end connected to the continuous extraction and liquid separation device and the acid buffer tank respectively, so as to continuously crystallize the heavy phase output from the continuous extraction and liquid separation device through hydrochloric acid and obtain a crystallization product.

[0039] Furthermore, the continuous post-processing device comprises: a continuous filtering device, the inlet of which is connected to the continuous crystallization component in the continuous extraction crystallization device, so as to continuously filter the crystallization product obtained by continuous crystallization of the continuous crystallization component to obtain a continuous filtration product, wherein the continuous filtration product comprises a crude lipoic acid product and a waste liquid;

[0040] A finished product storage tank, wherein the inlet of the finished product storage tank is connected to the first outlet of the continuous filtering device to collect the crude lipoic acid delivered from the first outlet;

[0041] The wastewater storage tank has an inlet connected to the second outlet of the continuous filtering device to collect the waste liquid transported from the second outlet.

[0042] By applying the technical solution of the utility model, the continuous feeding device ensures that the reaction raw materials are stably and continuously added to the reaction system, avoiding the instability of adding raw materials in batches during intermittent operation, improving production efficiency and raw material utilization rate, and facilitating precise control of reaction conditions.

[0043] The continuous device realizes the preparation of lipoic acid from ethyl 6,8-dichlorooctanoate. Continuous reaction can shorten the reaction time, improve the reaction rate and yield, avoid the side reactions and product polycondensation caused by local overheating in intermittent reactions, and the large heat exchange area in the reactor is conducive to the rapid transfer of heat and precise temperature control, which improves the selectivity of the reaction and the purity of the product.

[0044] The continuous concentration and separation device continuously concentrates and separates the reaction product ethyl lipoate, effectively removing light components such as solvents and volatile by-products to obtain a concentrated ethyl lipoate solution. This process significantly reduces the amount of solvent used in subsequent treatments, reduces the amount of wastewater generated, and improves the environmental protection and economic efficiency of the entire system.

[0045] The continuous hydrolysis and dilution device continuously hydrolyzes the concentrated ethyl lipoate solution under alkaline conditions to generate inorganic salts of lipoic acid. At the same time, the concentration and viscosity of the system are reduced by continuous dilution to facilitate subsequent treatment. Compared with intermittent reactions, the amount of water used in the continuous hydrolysis process is greatly reduced, which reduces the generation of wastewater and improves the selectivity and safety of the reaction.

[0046] The continuous extraction and crystallization device continuously extracts and crystallizes the hydrolyzed product to obtain crude lipoic acid. Continuous extraction improves the purity of the target product and reduces the amount of organic solvent used; continuous crystallization can accurately control the crystallization conditions, effectively reduce solid polymerization, further improve product purity and yield, and reduce production costs and improve production efficiency through continuous operation.

[0047] Through continuous production, material loss and equipment occupation in intermittent reactions are reduced, production costs are lowered, and the continuous process reduces the use of solvents and water, reduces the amount of wastewater, and improves the environmental friendliness of the production process. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The drawings constituting part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention. In the drawings:

[0049] Figure 1 The flowchart of the continuous device for preparing lipoic acid according to the embodiment of the present application is shown.

[0050] The above drawings include the following reference numerals:

[0051] 101, sulfide liquid storage tank; 102, 6,8-dichlorooctanoic acid ethyl ester storage tank; 103, first solvent storage tank; 104, sulfide liquid buffer tank; 105, 6,8-dichlorooctanoic acid ethyl ester buffer tank; 106, first solvent buffer tank;

[0052] 201. continuous cyclization reaction unit; 202. continuous impurity removal reaction unit; 203. sulfite storage tank;

[0053] 301, continuous liquid separation device; 302, continuous water washing device; 303, continuous concentration device; 304, continuous mixing component; 305, alkali solution storage tank; 306, sulfite buffer tank; 307, alkali solution buffer tank; 308, acid solution buffer tank;

[0054] 401. continuous hydrolysis device; 402. dilution liquid storage tank; 403. continuous dilution device;

[0055] 501, continuous extraction and liquid separation device; 502, second solvent storage tank; 503, light phase storage tank; 504, continuous crystallization component; 505, acid storage tank; 506, continuous filtration device; 507, finished product storage tank; 508, wastewater storage tank. DETAILED DESCRIPTION

[0056] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present utility model will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0057] Lipoic acid (CAS#62-46-4, chemical name 1,2-dithiocyclopentyl-3-pentanoic acid, molecular formula C8H14O2S2) can be used as a coenzyme to participate in the acyl transfer in the metabolism of substances in the body, can eliminate free radicals that lead to accelerated aging and disease, and has strong antioxidant capacity. It is currently the only drug that can meet the standard evaluation of antioxidants. It is called a universal antioxidant and belongs to the vitamin class of drugs.

[0058] Lipoic acid is mainly used as a medicine abroad. It enters cells after being absorbed through the intestines. It has the characteristics of both fat solubility and water solubility, and is also widely used as a dietary supplement and cosmetic raw material. In the domestic medical field, it is widely used to prevent and treat diabetes and its related complications. In the field of health care products, it is mainly used to remove free radicals in the body, prevent lipid peroxidation, and protect cells from oxidative damage, so as to achieve the purpose of preventing and assisting in the treatment of diseases.

[0059] Lipoic acid belongs to a class of compounds in the B vitamins. Since the 20th century, people have discovered that lipoic acid is not only an important coenzyme in organisms, but also plays an antioxidant role, which can protect biological tissues and lower blood sugar. In addition, lipoic acid is widely used in organic synthesis reactions as a catalyst or catalyst precursor, and is also used as an additive for rubber antioxidants and rubber processing aids in the materials industry. Structurally, lipoic acid is an eight-carbon fatty acid, in which a five-membered ring is formed by a disulfide bond between C6 and C8. Because the disulfide bond in the molecular structure is unstable, it will cause the disulfide bond in the five-membered ring to break when heated or exposed to light, and it is easy to produce very unstable free radicals. At the same time, the disulfide bond also has the properties of a dynamic covalent bond, so lipoic acid is very easy to interact with other molecules, and react with another molecule of lipoic acid at the position of the disulfide bond to form a polymer of lipoic acid.

[0060] The existing lipoic acid production process is mostly intermittent reaction (that is, the reaction raw materials are put into the reactor at one time for reaction). In the intermittent reaction process, there are disadvantages such as low production efficiency, unstable product quality, and poor safety.

[0061] The main purpose of the utility model is to provide a continuous device for preparing lipoic acid, so as to solve the problems of low production efficiency in the intermittent production of lipoic acid in the prior art.

[0062] The present application provides a continuous device for preparing thioctic acid, comprising: a continuous feeding device, wherein reaction raw materials are stored in the continuous feeding device, and the reaction raw materials include sulfide liquid, ethyl 6,8-dichlorooctanoate, sodium sulfite, alkali solution, acid solution and solvent;

[0063] A continuous reaction device, wherein the feed port of the continuous reaction device is connected to the discharge port of the continuous feeding device, so that the reaction raw materials react continuously in the continuous reaction device to generate a continuous reaction product, wherein the continuous reaction product is ethyl lipoate;

[0064] A continuous concentration and liquid separation device, wherein the feed port of the continuous concentration and liquid separation device is connected to the discharge port of the continuous reaction device, so as to continuously concentrate and separate the continuous reaction product to obtain a concentrated liquid separation product;

[0065] A continuous hydrolysis and dilution device, wherein the feed port of the continuous hydrolysis and dilution device is connected to the discharge port of the continuous concentration and liquid separation device to continuously hydrolyze and continuously dilute the concentrated and liquid-separated product to obtain a continuous hydrolysis and dilution product, wherein the continuous hydrolysis and dilution product is a sodium thioctic acid solution;

[0066] A continuous extraction and crystallization device is provided, wherein the feed port of the continuous extraction and crystallization device is connected with the discharge port of the continuous hydrolysis and dilution device, so as to continuously extract and crystallize the hydrolysis and dilution products, and input the products into a continuous post-treatment device for continuous post-treatment to obtain a crude lipoic acid product.

[0067] The continuous feeding device ensures that the reaction raw materials are stably and continuously added to the reaction system, avoiding the instability of adding raw materials in batches during intermittent operation, improving production efficiency and raw material utilization, and is conducive to precise control of reaction conditions.

[0068] The continuous device provided in the present application can realize the continuous preparation of lipoic acid using 6,8-dichlorooctanoic acid ethyl ester. The continuous reaction can shorten the reaction time, improve the reaction rate and yield, avoid the side reactions and product polycondensation caused by local overheating in the intermittent reaction, and at the same time, the large heat exchange area in the reactor is conducive to the rapid transfer of heat and precise temperature control, thereby improving the selectivity of the reaction and the purity of the product.

[0069] The continuous concentration and separation device continuously concentrates and separates the reaction product ethyl lipoate, effectively removing light components such as solvents and volatile by-products to obtain a concentrated ethyl lipoate solution. This process significantly reduces the amount of solvent used in subsequent treatments, reduces the amount of wastewater generated, and improves the environmental protection and economic efficiency of the entire system.

[0070] The continuous hydrolysis and dilution device continuously hydrolyzes the concentrated ethyl lipoate solution under alkaline conditions to generate inorganic salts of lipoic acid. At the same time, the concentration and viscosity of the system are reduced by continuous dilution to facilitate subsequent treatment. Compared with intermittent reactions, the amount of water used in the continuous hydrolysis process is greatly reduced, which reduces the generation of wastewater and improves the selectivity and safety of the reaction.

[0071] The continuous extraction and crystallization device continuously extracts and crystallizes the hydrolyzed product to obtain crude lipoic acid. Continuous extraction improves the purity of the target product and reduces the amount of organic solvent used; continuous crystallization can accurately control the crystallization conditions, effectively reduce solid polymerization, further improve product purity and yield, and reduce production costs and improve production efficiency through continuous operation.

[0072] Through continuous production, material loss and equipment occupation in intermittent reactions are reduced, production costs are lowered, and the continuous process reduces the use of solvents and water, reduces the amount of wastewater, and improves the environmental friendliness of the production process.

[0073] Further, the continuous feeding device comprises: a sulfide liquid storage tank 101, in which sulfide liquid is stored, and an outlet of the sulfide liquid storage tank 101 is connected to a first feed port of the continuous reaction device to transport the sulfide liquid to the continuous reaction device;

[0074] 6,8-dichlorooctanoic acid ethyl ester storage tank 102, the outlet of 6,8-dichlorooctanoic acid ethyl ester storage tank 102 is connected to the second feed inlet of the continuous reaction device to transport 6,8-dichlorooctanoic acid ethyl ester to the continuous reaction device;

[0075] The first solvent storage tank 103 has an outlet connected to the third feed port of the continuous reaction device so as to transport the first solvent to the continuous reaction device.

[0076] The reaction raw materials are independently stored and continuously supplied through the sulfide liquid storage tank 101, the 6,8-dichlorooctanoic acid ethyl ester storage tank 102, and the first solvent storage tank 103, respectively, to achieve accurate control and metering of the raw materials. This can ensure the accurate proportion of the raw materials during the reaction, improve the selectivity and yield of the reaction, and the continuous feeding can ensure that the reaction raw materials enter the continuous reaction device at a constant rate, avoiding the fluctuation of the reaction conditions that may be caused by intermittent feeding, ensuring the continuity and stability of the reaction process, and improving the consistency of product quality.

[0077] The continuous feeding method can make more efficient use of raw materials and reduce the waste of raw materials caused by intermittent operation. In continuous operation, the transportation of raw materials and the reaction process can be more closely coordinated, avoiding the excess and idleness of raw materials in intermittent operation.

[0078] The design of the continuous feeding device can adjust the feed rate and ratio in real time according to the specific needs of the reaction, thereby optimizing the reaction conditions such as temperature, pressure and reaction time. This flexibility helps to achieve the best reaction efficiency and product quality.

[0079] Continuous feeding avoids adding a large amount of raw materials to the reactor at one time, reducing safety risks in operation. Especially for flammable, explosive or toxic raw materials, continuous feeding can improve the safety of the entire production system.

[0080] Continuous feeding reduces the need for raw material storage and handling, reduces equipment investment and operating costs. At the same time, it reduces production costs by improving reaction efficiency and reducing by-products.

[0081] Continuous feeding helps to reduce raw material overflow and volatilization, reducing pollution to the environment. At the same time, due to the optimization of reaction conditions, the generation of wastewater and waste gas in the production process is reduced, improving the environmental friendliness of the entire production process.

[0082] Therefore, the continuous feeding device not only provides a stable and precise supply of raw materials for the continuous reaction, but also has an important positive impact on the efficiency and environmental friendliness of the entire lipoic acid continuous production system by optimizing reaction conditions, reducing waste, improving safety and reducing costs.

[0083] Furthermore, the continuous feeding device also includes:

[0084] The sulfide liquid buffer tank 104 is disposed between the sulfide liquid storage tank 101 and the first feed port to continuously transport the sulfide liquid to the continuous reaction device; and / or,

[0085] 6,8-dichlorooctanoic acid ethyl ester buffer tank 105, 6,8-dichlorooctanoic acid ethyl ester buffer tank 105 is arranged between 6,8-dichlorooctanoic acid ethyl ester storage tank 102 and the second feed port, so as to realize continuous delivery of 6,8-dichlorooctanoic acid ethyl ester to the continuous reaction device; and / or,

[0086] The first solvent buffer tank 106 is disposed between the first solvent storage tank 103 and the third feed port to realize continuous delivery of the first solvent to the continuous reaction device.

[0087] The above-mentioned various buffer tanks can adjust and stabilize the pressure of raw materials entering the continuous reaction device. In a continuous reaction system, stable feed pressure is essential to ensure uniform mixing of reactants and control the reaction rate. By providing a stable feed pressure, the buffer tank ensures that the reactants enter the reactor at a predetermined pressure and flow rate, thereby ensuring the consistency of reaction conditions.

[0088] The buffer tank can be used as an intermediate station for flow regulation. By controlling the amount of raw materials in the buffer tank or adjusting the opening of its discharge valve, the flow of raw materials entering the continuous reaction device can be adjusted in real time to cope with changes in reaction rate or adjustments in production demand.

[0089] When the raw material supply is insufficient or the equipment fails, the buffer tank can temporarily store the raw materials to avoid the reactor shutting down due to the interruption of raw material supply, thereby enhancing the emergency handling capability and continuous production capacity of the entire system.

[0090] By setting up a buffer tank between the raw material storage tank and the continuous reaction device, the fluctuation of direct feed can be reduced, and the safety problems that may be caused by sudden changes in feed pressure can be reduced. At the same time, the buffer tank also serves as a safety barrier to prevent the raw materials from directly entering the reactor, reducing the risks in operation.

[0091] Furthermore, the continuous reaction device comprises: a continuous cyclization reaction component 201, the continuous cyclization reaction component 201 has a first feed inlet, a second feed inlet and a third feed inlet, and the continuous cyclization reaction component 201 has a cyclization reaction site, so that the reaction raw materials undergo a continuous cyclization reaction in the cyclization reaction site;

[0092] A sulfite storage tank 203 , wherein sulfite is stored in the sulfite storage tank 203 ;

[0093] A continuous impurity removal reaction component 202, wherein the inlet of the continuous impurity removal reaction component 202 is connected to the outlet of the continuous cyclization reaction component 201 and the outlet of the sulfite storage tank 203, respectively, so that the sulfite in the continuous impurity removal reaction component 202 reacts with impurities formed after the continuous cyclization reaction in the continuous cyclization reaction component to obtain a continuous reaction product;

[0094] The sulfite buffer tank 306 is disposed between the sulfite storage tank 203 and the continuous impurity removal reaction component 202 to realize continuous transportation of sulfite to the continuous impurity removal reaction component 202 .

[0095] The provision of the sulfite buffer tank 306 can ensure that the sulfite stored in the sulfite storage tank 203 can stably enter the continuous impurity removal reaction component 202 .

[0096] The continuous cyclization reaction component 201 is one or more of a continuous plug flow reactor, a continuous overflow reactor, a continuous column reactor, and a continuous microchannel reactor;

[0097] The continuous impurity removal reaction component 202 is one or more of a continuous plug flow reactor, a continuous overflow reactor, a continuous column reactor, and a continuous microchannel reactor;

[0098] The continuous cyclization reaction component 201 provides a continuous cyclization reaction site, so that the reaction raw materials can quickly undergo cyclization reaction under stable conditions to generate continuous cyclization products. Compared with traditional intermittent reactions, continuous operation can significantly increase the reaction rate and shorten the reaction time, thereby improving production efficiency. At the same time, due to the continuous and stable reaction conditions, the occurrence of side reactions can be reduced, and the selectivity and yield of the target product can be improved.

[0099] Through the continuous impurity removal reaction component 202, sulfite is introduced to react with byproducts or impurities that may exist in the continuous cyclization product to achieve effective removal of these byproducts and impurities. Sulfite, as a reducing agent, can reduce oxidative impurities, or form substances that are easier to separate from impurities due to the characteristics of sulfite itself. This continuous impurity removal process improves the purity of the product and reduces the difficulty of subsequent processing steps.

[0100] The use of continuous reaction components enables more precise control of reaction conditions such as temperature, pressure, and reaction time. In particular, in the continuous cyclization reaction component 201, the continuous supply of raw materials and the continuous removal of products avoid the problems of local overheating and excessive residence time, which is beneficial to improving the selectivity of the reaction and reducing energy consumption.

[0101] By closely connecting the continuous cyclization reaction component 201 with the continuous impurity removal reaction component 202, a seamless link from the cyclization reaction to the impurity removal reaction is achieved, the continuity of the production process is ensured, the loss and pollution in the material transfer process are reduced, and the overall production efficiency is improved.

[0102] The precise temperature control and pressure management of the continuous reaction components, as well as the timely treatment of by-products, improve the safety of the production process. At the same time, continuous operation reduces the generation of wastewater and waste gas in intermittent reactions, reduces environmental pollution, and meets the high environmental protection requirements of modern chemical production.

[0103] The continuous reaction device reduces raw material consumption, energy consumption and wastewater treatment costs by improving reaction efficiency and reducing the generation of by-products, thereby effectively controlling production costs.

[0104] Furthermore, the continuous concentration and liquid separation device comprises: a continuous liquid separation device 301, the inlet of which is connected to the continuous impurity removal reaction component 202, so as to continuously separate the continuous reaction product transported from the continuous impurity removal reaction component 202 to obtain an organic phase and an aqueous phase, and transport the aqueous phase to an aqueous phase storage tank;

[0105] A continuous water washing device 302, the inlet of which is connected to the outlet of the continuous liquid separation device 301, for washing the organic phase with water to remove impurities in the organic phase and obtain a washed organic phase;

[0106] The continuous concentrating device 303 is connected to the continuous water washing device 302 to continuously concentrate the water-washed organic phase to obtain a concentrated liquid separation product, and the concentrated liquid separation product is a concentrated organic phase.

[0107] The continuous liquid separation device 301 can quickly and continuously separate the continuous reaction products into organic phase and aqueous phase. This continuous operation mode greatly improves the separation efficiency and reduces the residence time of the material during the liquid separation process, thereby avoiding side reactions or degradation that may occur due to long-term exposure to non-ideal conditions, and improving product purity and yield.

[0108] The organic phase is washed with water by the continuous water washing device 302, which can effectively remove water-soluble impurities therein and obtain a purer washed organic phase. The continuous water washing process can accurately control the water washing conditions and the amount of washing liquid, avoid the problem of excessive or insufficient washing liquid in intermittent operation, reduce resource waste and wastewater generation, and improve the environmental protection and economy of the entire production process.

[0109] The continuous concentration device 303 can continuously concentrate the organic phase after washing to obtain a concentrated organic phase, i.e., a concentrated liquid separation product. The concentration process helps to further remove residual solvent and water, improve the purity and recovery rate of the product, and also facilitate subsequent treatment, such as crystallization or drying. The continuous concentration operation can accurately control the evaporation rate and temperature, avoiding product degradation or loss due to excessive evaporation.

[0110] The continuous design of the continuous concentration and separation device enables the entire separation and purification process to be automated, reducing manual intervention, avoiding human operation errors, and improving the stability and controllability of the production process. At the same time, continuous operation can monitor and adjust working parameters such as temperature, pressure and flow rate in real time, ensuring the precise execution of process conditions.

[0111] The continuous operation mode reduces the amount of material to be processed and the complexity of the operation, and reduces the safety issues that may be caused by improper handling of large volumes of materials during the production process. At the same time, the continuous washing and concentration process significantly reduces the generation of wastewater and waste gas, and improves the environmental friendliness of the production process.

[0112] Furthermore, the continuous device also includes a continuous mixing component 304 disposed between the continuous concentration and separation device and the continuous hydrolysis and dilution device, and the inlet of the continuous mixing component 304 is respectively connected to the continuous concentration device 303 and the alkali solution storage tank 305, so that the alkali solution and the concentrated and separated liquid product are continuously mixed in the continuous mixing component 304 to obtain a continuous mixed product;

[0113] The continuous device also includes an alkali solution buffer tank 307 disposed between the alkali solution storage tank 305 and the continuous mixing component 304 to achieve continuous delivery of the alkali solution to the continuous mixing component 304;

[0114] Among them, the alkali solution is sodium hydroxide solution.

[0115] The setting of the continuous mixing component 304 ensures that the alkaline sodium hydroxide solution and the concentrated liquid separation product can be mixed evenly and continuously, which is crucial for the subsequent hydrolysis reaction. Accurate mixing helps to control the pH value of the reaction system, maintain it under suitable alkaline conditions, promote the hydrolysis of ethyl lipoate, and generate the target product lipoic acid. Continuous mixing can minimize the situation of local over-alkali or over-acid, and improve the selectivity and yield of the reaction.

[0116] In the continuous mixing part 304, the alkali solution and the concentrated liquid separation product can fully contact, which increases the contact area of ​​the reactants and is conducive to the subsequent hydrolysis reaction. Such full contact conditions can shorten the reaction time, improve the reaction efficiency, reduce the generation of by-products, and thus improve the product quality.

[0117] The provision of the alkali solution buffer tank 307 can ensure that the alkali solution in the alkali solution storage tank 305 can be transported to the continuous mixing component 304 at a stable pressure.

[0118] By continuously adding alkali solution, the material conditions before the hydrolysis reaction can be stabilized, avoiding the fluctuation of reaction conditions caused by adding too much alkali solution at one time in intermittent operation. This improvement in stability plays an important role in controlling the reaction rate and product quality.

[0119] The use of the continuous mixing component 304 simplifies the operation process from concentration and separation to hydrolysis reaction, avoids multiple transfers and treatments of materials, reduces possible material losses and contamination during the operation, and improves production efficiency and economic benefits.

[0120] The continuous mixing mode reduces the complexity of alkali solution and concentrated liquid separation product treatment, reduces the chance of operators coming into contact with strong alkaline substances, and improves production safety. At the same time, by accurately controlling the mixing ratio, it reduces the waste of alkali solution, reduces the burden of wastewater treatment, and improves the environmental protection of the entire production process.

[0121] The use of the continuous mixing component 304 helps to reduce the consumption of alkali solution and reduce production costs. At the same time, the precise control in the continuous operation reduces the waste of energy and further controls the overall production cost.

[0122] Further, the continuous hydrolysis and dilution device comprises: a continuous hydrolysis device 401, the inlet of the continuous hydrolysis device 401 is connected to the outlet of the continuous mixing component 304, so as to continuously hydrolyze the continuous mixed product to obtain a continuous hydrolysis product;

[0123] A diluent storage tank 402, wherein the diluent storage tank 402 stores a diluent, wherein the diluent is water;

[0124] The continuous dilution device 403 has an inlet which is connected to the outlet of the continuous hydrolyzate and the outlet of the storage tank of the diluent, respectively, so as to continuously dilute the continuous hydrolyzate with the diluent to obtain a hydrolyzed diluted product.

[0125] The continuous hydrolysis device 401 is one or more of a continuous plug flow reactor, a continuous overflow reactor, a continuous column reactor, and a continuous microchannel reactor.

[0126] The continuous hydrolysis device 401 can perform a rapid hydrolysis reaction on the continuous mixed product to convert ethyl lipoate into lipoic acid. Compared with the traditional intermittent hydrolysis method, the continuous operation can significantly accelerate the reaction process, shorten the hydrolysis time, and thus improve production efficiency. At the same time, the continuous hydrolysis operation can also more accurately control the reaction conditions, such as temperature and pH value, to ensure the efficient conduct of the hydrolysis reaction.

[0127] The concentration of the hydrolyzate can be precisely controlled by using the water from the dilution liquid storage tank 402 for dilution through the continuous dilution device 403, thereby avoiding side reactions caused by too high a concentration or waste of materials caused by too low a concentration. Continuous dilution can also effectively adjust the pH value of the reaction system to ensure smooth subsequent processing.

[0128] After the hydrolysis reaction, the product may have a high viscosity. Continuous dilution can reduce the viscosity of the reaction system, which is convenient for subsequent material transportation and processing. Reducing viscosity is conducive to improving the efficiency of processing equipment and reducing energy consumption.

[0129] Timely dilution can reduce the supersaturation of sodium lipoate in the hydrolyzate, prevent premature precipitation formation, ensure the stability of the product in solution, and facilitate subsequent crystallization or separation operations.

[0130] Continuous hydrolysis and dilution operations can be highly automated, reducing manual intervention and avoiding human operation errors. At the same time, the continuous process flow facilitates real-time monitoring and adjustment of reaction conditions, such as hydrolysis time, dilution flow rate, etc., ensuring the stability and controllability of process conditions.

[0131] Furthermore, the continuous extraction crystallization device comprises: a second solvent storage tank 502, in which a second solvent is stored, and the second solvent is any one or more of aliphatic hydrocarbons, aromatic hydrocarbons, alcohols, carboxylic acid esters, amides and heterocyclics;

[0132] A continuous extraction and liquid separation device 501, the inlet of which is respectively connected to the outlet of the continuous dilution device 403 in the continuous hydrolysis and dilution device and the second solvent storage tank 502, so as to continuously extract and separate the hydrolysis and dilution products through the second solvent to obtain a continuous extraction product, which includes a heavy phase and a light phase.

[0133] The continuous extraction and liquid separation device 501 can effectively separate impurities in the aqueous phase, such as unreacted alkali solution, by-products, etc., by introducing the second solvent to continuously extract the hydrolysis diluted product, thereby greatly improving the purity of the target product lipoic acid. The continuity of the extraction operation helps to maintain stable separation conditions and ensure the high quality of the product.

[0134] Through continuous extraction, the complexity of subsequent processing can be reduced, and the cumbersome operation of using multiple solvents or multiple extractions can be avoided. The continuous light phase and heavy phase separation process directly provides a relatively pure product, simplifies the conversion steps from hydrolyzate to final product, and improves production efficiency.

[0135] Continuous extraction operation can reduce the use of solvents and reduce the cost of solvent recovery and wastewater treatment. At the same time, the continuous process reduces the labor intensity of operators and reduces labor costs. In addition, precise control in continuous operation can reduce energy waste and further reduce production energy consumption.

[0136] Furthermore, the continuous extraction crystallization device further includes: a light phase storage tank 503, which is connected to the continuous extraction liquid separation device 501 to collect the light phase output from the continuous extraction liquid separation device 501;

[0137] Acid storage tank 505, wherein acid is stored in the acid storage tank 505, and the acid is hydrochloric acid;

[0138] An acid buffer tank 308, the inlet end of the acid buffer tank 308 is connected to the outlet end of the acid storage tank 505;

[0139] The continuous crystallization component 504 has its inlet end connected to the continuous extraction and liquid separation device 501 and the acid buffer tank 308 respectively, so as to continuously crystallize the heavy phase output from the continuous extraction and liquid separation device 501 with hydrochloric acid and obtain a crystallization product.

[0140] The light phase storage tank 503 is used to collect the light phase separated by the continuous extraction and liquid separation device 501, which usually contains unreacted solvent or by-products. Through the light phase storage tank, these substances can be recovered and recycled in other stages of the production process, thereby effectively saving raw material costs, reducing energy consumption for processing new solvents, and achieving efficient utilization of resources.

[0141] The continuous crystallization component 504 receives the heavy phase product from the continuous extraction and separation device 501 and the hydrochloric acid solution from the acid buffer tank 308 to perform a continuous crystallization process. Compared with intermittent operation, the continuous operation mode provides more stable and controllable crystallization conditions, avoids the problem of incomplete crystallization or inconsistent product purity caused by temperature and pH fluctuations in intermittent operation, thereby significantly improving the stability and purity of the crude lipoic acid.

[0142] The acid buffer tank 308 is connected to the acid storage tank 505 and is used to buffer the hydrochloric acid solution to ensure the stability of the concentration and flow of the acid in the continuous crystallization component 504. This precise control is crucial for the acid environment during the crystallization process, which can avoid side reactions caused by excessive acidification or insufficient acid, reduce energy consumption during the purification process, and improve the yield of lipoic acid.

[0143] Through the continuous design of the above components, the entire production process has been compacted and automated, reducing equipment idle time and improving equipment utilization and production efficiency. In the continuous operation mode, the equipment does not need to be started and stopped frequently, which reduces production costs and speeds up the conversion from raw materials to finished products.

[0144] The design of the continuous extraction crystallization device optimizes the post-processing process. The product after crystallization can directly enter the continuous post-processing device for further filtration and collection, reducing the steps of material transfer, reducing material loss and pollution risks caused by intermittent operation, and improving the continuity and overall efficiency of the production process.

[0145] Continuous operation reduces the chances of operators directly contacting chemicals and improves production safety. At the same time, the recycling of the light phase and the precise control of the acid reduce the waste and discharge of chemicals, reduce the burden of wastewater treatment, and embody the principles of green chemistry and sustainable production.

[0146] Further, the continuous post-processing device includes: a continuous filtering device 506, the inlet of the continuous filtering device 506 is connected to the continuous crystallization component 504 in the continuous extraction crystallization device, so as to continuously filter the crystallization product obtained by continuous crystallization of the continuous crystallization component 504 to obtain a continuous filtration product, and the continuous filtration product includes crude lipoic acid and waste liquid;

[0147] A finished product storage tank 507, wherein the inlet of the finished product storage tank 507 is connected to the first outlet of the continuous filtering device 506 to collect the crude lipoic acid delivered from the first outlet;

[0148] The wastewater storage tank 508 has an inlet connected to the second outlet of the continuous filtering device 506 to collect the waste liquid transported from the second outlet.

[0149] The continuous crystallization component 504 is one or more of a continuous plug flow reactor, a continuous overflow reactor, a continuous column reactor, and a continuous microchannel reactor.

[0150] The continuous filtering device 506 can filter the crystallization product quickly and continuously to separate the crude thioctic acid product and the waste liquid. Compared with intermittent filtering, the continuous filtering operation can significantly improve the filtering rate and production capacity, while reducing the residence time of the material in the equipment, preventing the thioctic acid from further reacting or degrading under high temperature or light conditions, and improving the purity and yield of the final crude thioctic acid product.

[0151] The use of continuous filtration equipment ensures that the crystallization product can be processed in time, avoiding the problem of material backlog in intermittent operation and reducing material loss or quality degradation caused by untimely processing. The entire post-processing process is smoother, improving equipment utilization and production efficiency.

[0152] The provision of the finished product storage tank 507 and the wastewater storage tank 508 enables accurate classification and collection of the thioctic acid crude product and waste liquid, which not only helps to simplify the post-processing process and reduce the complexity of the operation, but also facilitates further processing or recycling of the thioctic acid crude product and waste liquid, thereby improving the utilization efficiency of resources.

[0153] Compared with intermittent filtration, continuous filtration reduces the number of equipment startups and shutdowns and reduces energy consumption. At the same time, accurate material classification and collection reduces processing costs, especially the cost of waste liquid processing, because waste liquid can be purified or recycled in a targeted manner.

[0154] Continuous filtration reduces the chances of operators coming into contact with chemicals, especially when handling crystallization products, and improves production safety. In addition, timely classification and collection of waste liquids reduces the risk of environmental pollution, embodying the principles of green chemistry.

[0155] The use of continuous extraction equipment can continuously process the hydrolysis dilution product, improve the utilization rate of the equipment, and reduce the idle time of the equipment caused by intermittent operation. The continuous operation mode makes the entire production process more compact and efficient.

[0156] Example 1

[0157]

[0158] The continuous device provided in the embodiment of the present application includes a sulfide liquid storage tank 101, the sulfide liquid storage tank 101 and the 6,8-dichlorooctanoic acid ethyl ester storage tank 102 respectively prepare sufficient sulfide liquid (mainly containing sodium sulfide and sulfur) and 6,8-dichlorooctanoic acid ethyl ester, the first solvent storage tank 103 prepares sufficient solvent (such as toluene), the sulfide liquid buffer tank 104, the 6,8-dichlorooctanoic acid ethyl ester buffer tank 105 and the first solvent buffer tank 106 respectively increase the pressure of the material entering the continuous cyclization reaction component 201 to ensure continuous and stable feeding. The continuous cyclization reaction component 201 receives the feed from the sulfide liquid buffer tank 104, the 6,8-dichlorooctanoic acid ethyl ester buffer tank 105 and the first solvent buffer tank 106 under the set reaction conditions, and a continuous cyclization reaction occurs to generate thioctic acid ethyl ester, the reaction retention time is 10min, the reaction temperature is controlled at 60°C, and the reaction pressure is 0.1MPa. The sulfite storage tank 203 provides sodium sulfite as a by-product scavenger. The continuous impurity removal reaction component 202 receives ethyl thioctic acid and sodium sulfite from the continuous cyclization reaction component 201, performs impurity removal reaction, removes by-products, and generates purified ethyl thioctic acid. The reaction temperature of the continuous impurity removal reaction component 202 is 55°C, the pressure is 0.05MPa, and the reaction time is 5min. The continuous liquid separation device 301 continuously separates the product of the continuous impurity removal reaction component 202 to separate the organic phase (mainly containing ethyl thioctic acid) and the aqueous phase. The continuous water washing device 302 washes the organic phase to remove residual water-soluble impurities. The continuous concentrating device 303 continuously concentrates the organic phase after water washing to obtain a concentrated organic phase; the alkali liquid storage tank 305 prepares an appropriate amount of sodium hydroxide solution, and the continuous mixing component 304 mixes the concentrated organic phase with the sodium hydroxide solution to convert it into a sodium salt solution of thioctic acid. The continuous hydrolysis device 401 continuously hydrolyzes the mixed solution under set conditions to generate sodium salt of thioctic acid. The reaction temperature of the continuous hydrolysis device 401 is 80°C, the pH value is 10-12, and the reaction time is 20 minutes. The diluent storage tank 402 prepares sufficient water. The continuous dilution device 403 continuously dilutes the hydrolyzed product with water, adjusts the solution concentration, and prepares for the subsequent extraction step. The ratio of the dilution flow rate of the continuous dilution device 403 to the flow rate of the hydrolyzed product is 1:2. The second solvent storage tank 502 prepares a sufficient amount of the second solvent (such as hexane). The continuous extraction and liquid separation device 501 receives the hydrolysis dilution product and the second solvent from the continuous dilution device 403, performs continuous extraction and liquid separation, and obtains a heavy phase containing thioctic acid and a light phase containing water. The light phase enters the light phase storage tank 503 for storage, and the heavy phase enters the continuous crystallization component 504 for crystallization to obtain a crystallization product, which is input into the continuous filtration device 506, and the continuous filtration device 506 continuously filters the crystallization product to obtain a crude thioctic acid product and a waste liquid, and the crude thioctic acid product is transported to the finished product storage tank 507 for storage, and the waste liquid is transported to the wastewater storage tank 508 for storage.

[0159] Example 2

[0160] The reaction is different from that in Example 1, the continuous cyclization reaction component 201 is a continuous overflow reactor, and the retention time of the continuous cyclization reaction is increased by 30-40 min compared with that in Example 1. The final obtained crude thioctic acid A has a purity of 98.92% after continuous testing, and a total yield of 89.31%.

[0161] Example 3

[0162] The reaction is different from that in Example 1 in that the continuous impurity removal reaction component 202 is a continuous overflow reactor, and the impurities in the continuous impurity removal reaction component 202 are not completely converted. The final obtained crude lipoic acid A has a purity of 96.1% and a total yield of 88.13%.

[0163] Embodiment 4:

[0164] The reaction is different from that in Example 1, the continuous cyclization reaction component 201 is a microchannel reactor, and the retention time of the continuous cyclization reaction component 201 is reduced by 10-20 min compared with that in Example 1. The final obtained crude thioctic acid product A has a purity of 98.42% after continuous testing, and a total yield of 92.35%.

[0165] Embodiment 5:

[0166] The reaction is different from that in Example 1, the continuous hydrolysis device 401 is a continuous column reactor, the retention time is increased by 2 to 3 times, and the raw material is obviously left over, and finally a crude lipoic acid product A is obtained. The purity of the product after continuous testing is 97.23%, and the total yield is 81.23%.

[0167] Embodiment 6:

[0168] The reaction is different from that in Example 1, the continuous hydrolysis device 401 is a continuous overflow reactor, the retention time is increased by 60 min, and the raw material is obviously left over, and finally a crude lipoic acid product A is obtained. The purity of the product after continuous testing is 97.23%, and the total yield is 83.23%.

[0169] Embodiment 7:

[0170] The reaction is different from Example 1 in that a countercurrent columnar continuous extractor can be added between the outlet of the continuous water washing device 302 and the inlet of the continuous concentrating device 303. The extractor has a filler or a stirring element inside. The organic phase and the aqueous phase enter from both ends of the columnar extractor respectively and pass through the filler area in a countercurrent flow manner, which increases the effective contact time and area of ​​the two phases, improves the extraction selectivity and recovery rate, and adopts a countercurrent extraction method. The amount of purified water used is reduced by 1 time, and the amount of wastewater generated is greatly reduced. The purity of the continuous injection test product is 98.23%, and the total recovery is 91.23%.

[0171] Embodiment 8:

[0172] The reaction is different from that in Example 1, the continuous concentration device 303 increases the concentration temperature by 20° C., and the residual raw material in the continuous hydrolysis device 401 is significantly reduced, and finally a crude lipoic acid product A is obtained, and the purity of the product tested is 98.3%, and the total yield is 91.36%.

[0173] Embodiment 9:

[0174] The reaction is different from that in Example 1, the continuous concentration device 303 increases the concentration temperature by 60° C., and finally a crude lipoic acid product A is obtained. The purity of the product tested is 98.39%, and the total yield is 87.62%.

[0175] Embodiment 10:

[0176] The reaction is different from that in Example 1, the continuous dilution device 403 is changed to a continuous overflow reactor, and finally a crude lipoic acid product A is obtained, and the purity of the product is 98.9%, and the total yield is 91.31%.

[0177] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0178] Unless otherwise specifically stated, the relative arrangement, numerical expressions and numerical values ​​of the parts and steps set forth in these embodiments do not limit the scope of the utility model. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be considered as a part of the specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, and therefore, once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0179] In the description of the present utility model, it needs to be understood that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present utility model and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction, and therefore cannot be understood as limiting the scope of protection of the present utility model; the directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0180] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0181] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the utility model.

[0182] The above description is only the preferred embodiment of the utility model, and is not intended to limit the utility model. For those skilled in the art, the utility model can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A continuous device for preparing thioctic acid, characterized in that, include: A continuous feeding device, wherein the continuous feeding device stores reaction raw materials, and the reaction raw materials include sulfide liquid, ethyl 6,8-dichlorooctanoate, sodium sulfite, alkali solution, acid solution and solvent; A continuous reaction device, wherein the feed port of the continuous reaction device is connected to the discharge port of the continuous feeding device, so that the reaction raw materials react continuously in the continuous reaction device to generate a continuous reaction product, wherein the continuous reaction product is ethyl lipoate; A continuous concentration and liquid separation device, wherein the feed port of the continuous concentration and liquid separation device is connected to the discharge port of the continuous reaction device, so as to continuously concentrate and separate the continuous reaction product to obtain a concentrated liquid separation product; A continuous hydrolysis and dilution device, wherein the feed port of the continuous hydrolysis and dilution device is connected to the discharge port of the continuous concentration and liquid separation device, so as to continuously hydrolyze and continuously dilute the concentrated and liquid-separated product to obtain a continuous hydrolysis and dilution product, wherein the continuous hydrolysis and dilution product is a sodium lipoic acid solution; A continuous extraction and crystallization device, wherein the feed port of the continuous extraction and crystallization device is connected to the discharge port of the continuous hydrolysis and dilution device, so as to continuously extract and crystallize the hydrolysis and dilution products, and input them into a continuous post-treatment device for continuous post-treatment to obtain a crude lipoic acid product.

2. The continuous device for preparing thioctic acid according to claim 1, characterized in that, The continuous feeding device comprises: A sulfide liquid storage tank (101), wherein the sulfide liquid is stored in the sulfide liquid storage tank (101), and an outlet of the sulfide liquid storage tank (101) is connected to a first feed inlet of the continuous reaction device so as to transport the sulfide liquid to the continuous reaction device; A 6,8-dichlorooctanoic acid ethyl ester storage tank (102), wherein the outlet of the 6,8-dichlorooctanoic acid ethyl ester storage tank (102) is connected to the second feed inlet of the continuous reaction device so as to transport the 6,8-dichlorooctanoic acid ethyl ester to the continuous reaction device; A first solvent storage tank (103), wherein the outlet of the first solvent storage tank (103) is connected to the third feed inlet of the continuous reaction device so as to transport the first solvent to the continuous reaction device.

3. The continuous device for preparing thioctic acid according to claim 2, characterized in that, The continuous feeding device also includes: a sulfide liquid buffer tank (104), the sulfide liquid buffer tank (104) being arranged between the sulfide liquid storage tank (101) and the first feed port, so as to realize continuous delivery of the sulfide liquid to the continuous reaction device; and / or, a 6,8-dichlorooctanoic acid ethyl ester buffer tank (105), wherein the 6,8-dichlorooctanoic acid ethyl ester buffer tank (105) is disposed between the 6,8-dichlorooctanoic acid ethyl ester storage tank (102) and the second feed port, so as to realize continuous delivery of the 6,8-dichlorooctanoic acid ethyl ester to the continuous reaction device; and / or, A first solvent buffer tank (106), wherein the first solvent buffer tank (106) is disposed between the first solvent storage tank (103) and the third feed port, so as to realize continuous delivery of the first solvent to the continuous reaction device.

4. The continuous device for preparing thioctic acid according to claim 2, characterized in that, The continuous reaction device comprises: A continuous cyclization reaction component (201), wherein the continuous cyclization reaction component (201) has the first feed port, the second feed port, and the third feed port, and the continuous cyclization reaction component (201) has a cyclization reaction site, so that the reaction raw materials undergo a continuous cyclization reaction in the cyclization reaction site; a sulfite storage tank (203), wherein sulfite is stored in the sulfite storage tank (203); a continuous impurity removal reaction component (202), wherein the inlet of the continuous impurity removal reaction component (202) is respectively connected to the outlet of the continuous cyclization reaction component (201) and the outlet of the sulfite storage tank (203), so that the sulfite in the continuous impurity removal reaction component (202) reacts with impurities formed after the continuous cyclization reaction in the continuous cyclization reaction component (201), thereby obtaining the continuous reaction product; A sulfite buffer tank (306), wherein the sulfite buffer tank (306) is disposed between the sulfite storage tank (203) and the continuous impurity removal reaction component (202) to achieve continuous transport of the sulfite to the continuous impurity removal reaction component (202).

5. The continuous device for preparing thioctic acid according to claim 4, characterized in that, The continuous concentration and liquid separation device comprises: A continuous liquid separation device (301), wherein the inlet of the continuous liquid separation device (301) is connected to the continuous impurity removal reaction component (202), so as to continuously separate the continuous reaction product transported from the continuous impurity removal reaction component (202) to obtain an organic phase and an aqueous phase, and transport the aqueous phase to an aqueous phase storage tank; A continuous water washing device (302), wherein the inlet of the continuous water washing device (302) is connected to the outlet of the continuous liquid separation device (301), so as to wash the organic phase with water to remove impurities in the organic phase and obtain a water-washed organic phase; A continuous concentrating device (303), the continuous concentrating device (303) is connected to the continuous water washing device (302) to continuously concentrate the water-washed organic phase to obtain the concentrated liquid separation product, and the concentrated liquid separation product is the concentrated organic phase.

6. The continuous device for preparing thioctic acid according to claim 5, characterized in that, The continuous device further comprises a continuous mixing component (304) disposed between the continuous concentration and liquid separation device and the continuous hydrolysis and dilution device, wherein the inlet of the continuous mixing component (304) is respectively connected to the continuous concentration device (303) and the alkali solution storage tank (305), so that the alkali solution and the concentrated and liquid separation product are continuously mixed in the continuous mixing component (304) to obtain a continuous mixed product; The continuous device further comprises an alkali solution buffer tank (307) disposed between the alkali solution storage tank (305) and the continuous mixing component (304) so ​​as to realize continuous conveying of the alkali solution to the continuous mixing component (304); Wherein, the alkali solution is sodium hydroxide solution.

7. The continuous device for preparing thioctic acid according to claim 6, characterized in that, The continuous hydrolysis and dilution device comprises: A continuous hydrolysis device (401), wherein the inlet of the continuous hydrolysis device (401) is connected to the outlet of the continuous mixing component (304) to continuously hydrolyze the continuous mixed product to obtain a continuous hydrolysis product; A diluent storage tank (402), wherein the diluent storage tank (402) stores a diluent, wherein the diluent is water; A continuous dilution device (403), wherein the inlet of the continuous dilution device (403) is respectively connected to the outlet of the continuous hydrolyzate and the outlet of the storage tank of the diluent, so as to continuously dilute the continuous hydrolyzate with the diluent to obtain a hydrolyzed diluted product.

8. The continuous device for preparing thioctic acid according to claim 1, characterized in that, The continuous extraction crystallization device comprises: A second solvent storage tank (502), wherein the second solvent storage tank (502) stores a second solvent, wherein the second solvent is any one or more of aliphatic hydrocarbons, aromatic hydrocarbons, alcohols, carboxylic acid esters, amides and heterocyclics; A continuous extraction and liquid separation device (501), wherein the inlet of the continuous extraction and liquid separation device (501) is respectively connected to the outlet of the continuous dilution device (403) in the continuous hydrolysis and dilution device and the second solvent storage tank (502), so as to continuously extract and separate the hydrolysis and dilution products through the second solvent to obtain a continuous extraction product, wherein the continuous extraction product includes a heavy phase and a light phase.

9. The continuous device for preparing thioctic acid according to claim 8, characterized in that, The continuous extraction crystallization device also includes: A light phase storage tank (503), the light phase storage tank (503) being in communication with the continuous extraction and liquid separation device (501) to collect the light phase output from the continuous extraction and liquid separation device (501); An acid liquid storage tank (505), wherein the acid liquid storage tank (505) stores acid liquid, and the acid liquid is hydrochloric acid; An acid liquid buffer tank (308), wherein the inlet end of the acid liquid buffer tank (308) is connected to the outlet end of the acid liquid storage tank (505); A continuous crystallization component (504), wherein the inlet end of the continuous crystallization component (504) is respectively connected to the continuous extraction and liquid separation device (501) and the acid buffer tank (308), so as to continuously crystallize the heavy phase output from the continuous extraction and liquid separation device (501) by the hydrochloric acid and obtain a crystallization product.

10. The continuous device for preparing thioctic acid according to claim 1, characterized in that: The continuous post-processing device comprises: A continuous filtering device (506), wherein the inlet of the continuous filtering device (506) is connected to the continuous crystallization component (504) in the continuous extraction crystallization device, so as to continuously filter the crystallization product obtained by continuous crystallization of the continuous crystallization component (504) to obtain a continuous filtration product, wherein the continuous filtration product includes the crude lipoic acid product and waste liquid; A finished product storage tank (507), wherein the inlet of the finished product storage tank (507) is connected to the first outlet of the continuous filtering device (506) to collect the crude lipoic acid product transported from the first outlet; A wastewater storage tank (508), wherein the inlet of the wastewater storage tank (508) is connected to the second outlet of the continuous filtering device (506) to collect the waste liquid transported from the second outlet.

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