A L-carnitine refining system

Abstract

This invention discloses a L-carnitine refining system, belonging to the field of L-carnitine refining. It includes an anode plate, a first cation exchange membrane, at least one repeating unit, a third cation exchange membrane, and a cathode plate arranged sequentially from left to right. The repeating unit includes a first anion exchange membrane, a second anion exchange membrane, and a second cation exchange membrane arranged sequentially from left to right. A first electrode chamber is formed between the anode plate and the first cation exchange membrane; a first recovery chamber is formed between the first cation exchange membrane and the first anion exchange membrane; a feed chamber is formed between the first anion exchange membrane and the second anion exchange membrane; a replenishment chamber is formed between the second anion exchange membrane and the second cation exchange membrane; a second recovery chamber is formed between the second cation exchange membrane and the third cation exchange membrane; and a second electrode chamber is formed between the third cation exchange membrane and the cathode plate. This invention replaces the bipolar membrane with a conventional anion / cation exchange membrane combination, reducing the loss of active ingredients to improve yield, and has low energy consumption.

Description

Technical Field

[0001] This utility model belongs to the field of L-carnitine refining, and particularly relates to an L-carnitine refining system. Background Technology

[0002] L-Carnitine is an important amino acid derivative widely found in organisms, playing an indispensable role in the β-oxidation of fatty acids and energy metabolism in the human body. Due to its widespread applications in nutritional supplements, pharmaceuticals (such as improving myocardial function and treating carnitine deficiency), sports nutrition, and feed additives, the market demand for high-purity, high-quality L-carnitine continues to grow. The industrial production of L-carnitine mainly relies on chemical synthesis or bio-fermentation methods. It typically exists in the form of an organic salt and requires appropriate treatment to remove acid radicals, thereby obtaining free L-carnitine.

[0003] The refining of L-carnitine is often achieved through adsorption using anion exchange resins. However, the resin regeneration process generates a large amount of regeneration wastewater, causing environmental pollution and increasing overall costs. Therefore, electrochemical methods can be used for refining. L-carnitine can also be refined using bipolar membrane electrodialysis. However, due to the characteristics of bipolar membranes—specifically, their limited retention rate of L-carnitine cations—some active ingredients enter the recovery solution, resulting in a reduced yield. Furthermore, bipolar membrane electrodialysis requires a high DC voltage for water dissociation, leading to high energy consumption per unit of L-carnitine. Therefore, bipolar membrane electrodialysis suffers from high loss rates and high energy consumption. Utility Model Content

[0004] The purpose of this invention is to provide a L-carnitine refining system to overcome at least one of the above-mentioned defects in the prior art.

[0005] To achieve this objective, the present invention adopts the following technical solution:

[0006] This utility model provides a L-carnitine refining system, comprising an anode plate, a first cation exchange membrane, at least one repeating unit, a third cation exchange membrane, and a cathode plate arranged sequentially from left to right. The repeating unit includes a first anion exchange membrane, a second anion exchange membrane, and a second cation exchange membrane arranged sequentially from left to right. A first electrode liquid chamber is formed between the anode plate and the first cation exchange membrane, a first recovery chamber is formed between the first cation exchange membrane and the first anion exchange membrane, a raw liquid chamber is formed between the first anion exchange membrane and the second anion exchange membrane, a replenishment chamber is formed between the second anion exchange membrane and the second cation exchange membrane, a second recovery chamber is formed between the second cation exchange membrane and the third cation exchange membrane, and a second electrode liquid chamber is formed between the third cation exchange membrane and the cathode plate.

[0007] Preferably, the system further includes a raw liquid tank, an electrode liquid tank, a recovery liquid tank, and a replenishment liquid tank. The outlet of the raw liquid tank is connected to the inlet of the raw liquid chamber, and the outlet of the raw liquid chamber is connected to the inlet of the raw liquid tank. The outlet of the electrode liquid tank is connected to the inlets of the first electrode liquid chamber and the second electrode liquid chamber, respectively. The outlets of the first electrode liquid chamber and the second electrode liquid chamber are both connected to the inlet of the electrode liquid tank. The outlet of the recovery liquid tank is connected to the inlets of the first recovery chamber and the second recovery chamber, respectively. The outlets of the first recovery chamber and the second recovery chamber are both connected to the inlet of the recovery liquid tank. The outlet of the replenishment liquid tank is connected to the inlet of the replenishment chamber, and the outlet of the replenishment chamber is connected to the inlet of the replenishment liquid tank.

[0008] Preferably, the operating voltage of the repetitive unit is 0.5-2.0V, and the operating current density is 30-500A / m. 2 .

[0009] Preferably, the number of repeating units is 1-200.

[0010] Preferably, both the anode plate and the cathode plate are titanium-coated ruthenium-iridium electrodes, titanium electrodes, or platinum electrodes.

[0011] Preferably, the system further includes a first water pump, a second water pump, a third water pump, and a fourth water pump. The first water pump is installed between the outlet of the raw liquid tank and the inlet of the raw liquid chamber. The second water pump is installed between the outlet of the polar liquid tank and the inlets of the first and second polar liquid chambers, and is located near the outlet of the polar liquid tank. The third water pump is installed between the outlet of the recovered liquid tank and the inlets of the first and second recovered chambers, and is located near the outlet of the recovered liquid tank. The fourth water pump is installed between the outlet of the replenishment liquid tank and the inlet of the replenishment chamber.

[0012] Preferably, it also includes a DC power supply, the positive output terminal of which is electrically connected to the anode plate, and the negative output terminal of which is electrically connected to the cathode plate.

[0013] Preferably, it also includes clamping plates, with clamping plates provided on the left side of the anode plate and the right side of the cathode plate.

[0014] Preferably, the clamping plate is made of PVC, PP, PTFE or PMMA.

[0015] The beneficial effects of this utility model are as follows:

[0016] 1. Replace the bipolar membrane with a conventional anion / cation exchange membrane combination, using the first and second anion exchange membranes to retain L-CN. + It reduces the loss of active ingredients to improve yield, eliminates the need for the high-voltage process of bipolar membrane water dissociation, and has low operating parameters. At the same time, it leverages the advantages of conventional membranes with strong tolerance and simple polar liquid circulation to solve the pain points of low yield and high energy consumption in bipolar membrane electrodialysis, thus achieving efficient and stable purification of L-carnitine.

[0017] 2. The water tank circulation system solves the problem of insufficient purity in a single treatment by means of closed-loop flow and directional separation, and realizes resource recovery and system stability, perfectly making up for the shortcomings of low yield and high energy consumption of traditional bipolar membrane electrodialysis.

[0018] 3. The processing scale and refining level can be flexibly adjusted according to actual production needs, which can meet the needs of small-batch high-precision refining as well as adapt to large-scale production. Attached Figure Description

[0019] Figure 1 This is a schematic diagram illustrating the working principle of this utility model.

[0020] Figure 2 This is a schematic diagram of the system structure of this utility model.

[0021] The labels in the attached diagram are as follows: 1-Anode plate, 2-First cation exchange membrane, 3-Repetition unit, 4-Third cation exchange membrane, 5-Cathode plate, 31-First anion exchange membrane, 32-Second anion exchange membrane, 33-Second cation exchange membrane, 6-First electrode liquid chamber, 7-First recovery chamber, 8-Source solution chamber, 9-Replenishment chamber, 10-Second recovery chamber, 11-Second electrode liquid chamber, 12-Source solution tank, 13-Electrode solution tank, 14-Recovery solution tank, 15-Replenishment solution tank, 16-First water pump, 17-Second water pump, 18-Third water pump, 19-Fourth water pump, 20-DC power supply, 21-Clamping plate. Detailed Implementation

[0022] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments.

[0023] Contents not described in detail in this specification are existing technologies known to those skilled in the art. In the description of this utility model, it should be understood that terms such as "center," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are used only for the convenience of describing this utility model and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting this utility model. Furthermore, terms such as "first," "second," and "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0024] like Figures 1 to 2As shown, the L-carnitine refining system provided in this embodiment includes an anode plate 1, a first cation exchange membrane 2, at least one repeating unit 3, a third cation exchange membrane 4, and a cathode plate 5 arranged sequentially from left to right. The repeating unit 3 includes a first anion exchange membrane 31, a second anion exchange membrane 32, and a second cation exchange membrane 33 arranged sequentially from left to right. A first electrode liquid chamber 6 is formed between the anode plate 1 and the first cation exchange membrane 2. A first recovery chamber 7 is formed between the first cation exchange membrane and the first anion exchange membrane. A raw liquid chamber 8 is formed between the first anion exchange membrane and the second anion exchange membrane. A replenishment chamber 9 is formed between the second anion exchange membrane and the second cation exchange membrane. A second recovery chamber 10 is formed between the second cation exchange membrane and the third cation exchange membrane. A second electrode liquid chamber 11 is formed between the third cation exchange membrane and the cathode plate 5.

[0025] In this embodiment, L-carnitine hydrochloride is used as the stock solution and sodium hydroxide is used as the replenishing solution.

[0026] A direct current electric field is applied between the anode plate 1 and the cathode plate 5. L-carnitine hydrochloride dissolves and ionizes in the original solution chamber 8, producing L-carnitine cations (L-CN). + Sodium hydroxide in the replenishment solution dissolves and ionizes in replenishment chamber 9, producing sodium ions (Na⁺) and chloride ions (Cl⁻). + ) and hydroxide ions (OH-). Under the drive of an electric field, cations (such as L-CN) and hydroxide ions (OH-) react to form hydroxide ions. + Na + Cations move towards the cathode (right side), while anions (such as Cl-, OH-) move towards the anode (left side). The first anion exchange membrane 31 and the second anion exchange membrane 32 only allow anions to pass through. Cl- in the feed chamber 8 passes through the first anion exchange membrane 31 into the first recovery chamber 7, and OH- in the replenishment chamber 9 passes through the second anion exchange membrane 32 into the feed chamber 8, where it combines with L-CN. The first cation exchange membrane 2, the second cation exchange membrane 33, and the third cation exchange membrane 4 only allow cations to pass through. L-CN in the feed chamber 8... + Na in supply room 9 + It moves towards the cathode, but since both sides of the original liquid chamber 8 are anion exchange membranes, L-CN + The Na was retained in the original solution chamber 8. Meanwhile, the Na in the replenishment chamber 9... + The Na+ passes through the second cation exchange membrane 33 into the second recovery chamber 10 and is continuously washed away by the recovery liquid. Therefore, it does not have time to pass through the third cation exchange membrane into the second electrode chamber 11. + Confined in the second recovery chamber 10, it becomes part of the recovery liquid. The flow of the electrode liquid in the first electrode liquid chamber 6 and the second electrode liquid chamber 11 is used to conduct current, cool the electrodes, remove electrode reaction products, and maintain system stability.

[0027] This invention abandons bipolar membranes and uses a conventional anion / cation exchange membrane combination, using the first anion exchange membrane 31 and the second anion exchange membrane 32 to retain L-CN. + This design avoids the entry of L-carnitine cations into the recovery solution due to insufficient retention of the bipolar membrane, significantly reducing the loss of active ingredients and improving yield. It eliminates the need for the high-voltage process of bipolar membrane water dissociation, relying solely on the selective migration of ions through conventional anion / cation exchange membranes. The electric field is primarily used to drive the directional movement of ions, significantly reducing unit energy consumption. Specifically, the operating voltage of repeating unit 3 is only 0.5-2.0V, and the operating current density is only 30-500A / m³. 2 The simple circulation of the electrode solution reduces additional energy consumption, resulting in better overall system energy efficiency. Conventional ion exchange membranes (non-bipolar membranes) are more robust, and electrode reaction products are discharged through the electrode solution, reducing membrane fouling and performance degradation, ensuring long-term stable system operation. This system replaces bipolar membranes with conventional anion / cation exchange membranes, utilizing ion selective migration and electric field drive to precisely address the yield and energy consumption pain points of bipolar membrane electrodialysis, while simultaneously considering purification efficiency, purity, and system stability, achieving highly efficient purification of L-carnitine.

[0028] It also includes a raw liquid tank 12, an electrode liquid tank 13, a recovery liquid tank 14, a replenishment liquid tank 15, a first water pump 16, a second water pump 17, a third water pump 18, a fourth water pump 19, a clamping plate 21, and a DC power supply 20.

[0029] The outlet of the raw liquid tank 12 is connected to the inlet of the raw liquid chamber 8, and the outlet of the raw liquid chamber 8 is connected to the inlet of the raw liquid tank 12. The outlet of the polar liquid tank 13 is connected to the inlet of the first polar liquid chamber 6 and the second polar liquid chamber 11, respectively. The outlets of the first polar liquid chamber 6 and the second polar liquid chamber 11 are both connected to the inlet of the polar liquid tank 13. The outlet of the recovery liquid tank 14 is connected to the inlet of the first recovery chamber 7 and the second recovery chamber 10, respectively. The outlets of the first recovery chamber 7 and the second recovery chamber 10 are both connected to the inlet of the recovery liquid tank 14. The outlet of the replenishment liquid tank 15 is connected to the inlet of the replenishment chamber 9, and the outlet of the replenishment chamber 9 is connected to the inlet of the replenishment liquid tank 15. A first water pump 16 is installed between the outlet of the raw liquid tank 12 and the inlet of the raw liquid chamber 8. A second water pump 17 is installed between the outlet of the electrode liquid tank 13 and the inlets of the first electrode liquid chamber 6 and the second electrode liquid chamber 11, with the second water pump 17 positioned near the outlet of the electrode liquid tank 13. A third water pump 18 is installed between the outlet of the recovery liquid tank 14 and the inlets of the first recovery chamber 7 and the second recovery chamber 10, with the third water pump 18 positioned near the outlet of the recovery liquid tank 14. A fourth water pump 19 is installed between the outlet of the replenishment liquid tank 15 and the inlet of the replenishment chamber 9. The positive output terminal of the DC power supply 20 is electrically connected to the anode plate 1, and the negative output terminal of the DC power supply 20 is electrically connected to the cathode plate 5. Clamping plates 21 are installed on the left side of the anode plate 1 and the right side of the cathode plate 5.

[0030] L-carnitine hydrochloride stock solution is pumped from stock solution tank 12 into stock solution chamber 8 via the first water pump 16. The refined stock solution (rich in L-carnitine) flows back to stock solution tank 12 from the outlet of stock solution chamber 8, forming a cycle. As the cycle continues, the Cl- in the stock solution continuously decreases, and the purity of L-carnitine gradually increases.

[0031] Electrode solutions are pumped from the electrode solution tank 13 into the first electrode solution chamber 6 and the second electrode solution chamber 11 via the second water pump 17. The circulating electrode solutions carry away the gases and ions generated in the reaction, maintain the pH stability of the first electrode solution chamber 6 and the second electrode solution chamber 11, prevent electrode corrosion, and enhance the efficiency of the electric field through ion conduction.

[0032] The recovered liquid is pumped from the recovered liquid tank 14 into the first recovery chamber 7 and the second recovery chamber 10 via the third water pump 18. The enriched recovered liquid is then returned to the recovered liquid tank 14 to achieve Na… + Centralized recovery of Cl-.

[0033] Sodium hydroxide replenishment solution is pumped from replenishment solution tank 15 into replenishment chamber 9 via fourth water pump 19. Replenishment solution circulation ensures a continuous supply of OH-, maintaining the purified environment of original solution chamber 8, while preventing ion depletion in replenishment chamber 9.

[0034] The water tank circulation system solves the problem of insufficient purity in a single treatment by using closed-loop flow and directional separation, and also achieves resource recovery and system stability, perfectly making up for the shortcomings of low yield and high energy consumption of traditional bipolar membrane electrodialysis.

[0035] Among them, repeating unit 3 has 1-200 units. The processing scale and purification level can be flexibly adjusted according to actual production needs, which can meet the needs of small-batch high-precision purification as well as adapt to large-scale production, improve the system's adaptability to different yield and purity requirements, and enhance the ion separation effect through multi-unit collaboration, further ensuring the purification efficiency and purity of L-carnitine.

[0036] Both the anode plate 1 and the cathode plate 5 are titanium-coated ruthenium-iridium electrodes, titanium electrodes, or platinum electrodes. These electrodes have excellent conductivity, which can stably transmit the electric field and ensure the efficiency of ion directional migration, avoiding the impact of poor conductivity on the purification effect; at the same time, they have high chemical stability and strong corrosion resistance, making them suitable for long-term continuous operation.

[0037] The clamping plate 21 is made of PVC, PP, PTFE, or PMMA. These materials have strong chemical stability and excellent corrosion resistance, and are not prone to aging or damage with long-term use, thus extending the service life of the clamping plate 21. They are lightweight and have suitable mechanical strength, facilitating system assembly and disassembly while providing stable clamping to ensure the stability of the membrane stack structure during electrodialysis and prevent leakage due to insufficient clamping force.

[0038] The above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A L-carnitine refining system, characterized in that: It includes, from left to right, an anode plate, a first cation exchange membrane, at least one repeating unit, a third cation exchange membrane, and a cathode plate; The repeating unit includes a first anion exchange membrane, a second anion exchange membrane, and a second cation exchange membrane arranged sequentially from left to right; A first electrode chamber is formed between the anode plate and the first cation exchange membrane; A first recovery chamber is formed between the first cation exchange membrane and the first anion exchange membrane; A raw liquid chamber is formed between the first anion exchange membrane and the second anion exchange membrane; A recharge chamber is formed between the second anion exchange membrane and the second cation exchange membrane; A second recovery chamber is formed between the second cation exchange membrane and the third cation exchange membrane; A second electrode liquid chamber is formed between the third cation exchange membrane and the cathode plate.

2. The L-carnitine refining system according to claim 1, characterized in that: It also includes a raw liquid tank, an electrode liquid tank, a recovery liquid tank, and a replenishment liquid tank; The outlet of the raw liquid tank is connected to the inlet of the raw liquid chamber, and the outlet of the raw liquid chamber is connected to the inlet of the raw liquid tank. The outlet of the polar liquid tank is connected to the inlet of the first polar liquid chamber and the second polar liquid chamber respectively, and the outlets of the first polar liquid chamber and the second polar liquid chamber are both connected to the inlet of the polar liquid tank. The outlet of the recovered liquid tank is connected to the inlet of the first recovery chamber and the second recovery chamber respectively, and the outlet of the first recovery chamber and the second recovery chamber are both connected to the inlet of the recovered liquid tank. The outlet of the replenishment fluid tank is connected to the inlet of the replenishment chamber, and the outlet of the replenishment chamber is connected to the inlet of the replenishment fluid tank.

3. The L-carnitine refining system according to claim 2, characterized in that: The operating voltage of the repetitive unit is 0.5-2.0V, and the operating current density is 30-500A / m. 2 .

4. The L-carnitine refining system according to claim 1, characterized in that: The number of repeating units is 1-200.

5. The L-carnitine refining system according to claim 1, characterized in that: Both the anode plate and the cathode plate are titanium-coated ruthenium-iridium electrodes, titanium electrodes, or platinum electrodes.

6. The L-carnitine refining system according to claim 2, characterized in that: It also includes a first water pump, a second water pump, a third water pump, and a fourth water pump; A first water pump is installed between the outlet of the raw liquid tank and the inlet of the raw liquid chamber. A second water pump is provided between the outlet of the polar liquid tank and the inlet of the first polar liquid chamber and the second polar liquid chamber, and the second water pump is located near the outlet of the polar liquid tank. A third water pump is provided between the outlet of the recycled liquid tank and the inlet of the first and second recycling chambers, and the third water pump is located near the outlet of the recycled liquid tank. A fourth water pump is installed between the outlet of the replenishment fluid tank and the inlet of the replenishment chamber.

7. The L-carnitine refining system according to claim 1, characterized in that: It also includes a DC power supply; The positive output terminal of the DC power supply is electrically connected to the anode plate; The negative output terminal of the DC power supply is electrically connected to the cathode plate.

8. The L-carnitine refining system according to claim 1, characterized in that: It also includes clamping plates; Clamping plates are provided on the left side of the anode plate and the right side of the cathode plate.

9. The L-carnitine refining system according to claim 8, characterized in that: The clamping plate is made of PVC, PP, PTFE or PMMA.

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