An integrated extraction, crystallization, and filtration apparatus and method

Abstract

This invention discloses a three-in-one operation device and method for extraction, crystallization, and filtration, including a reaction vessel. The reaction vessel is equipped with an upper end cap plate, on which a feed pipe and a feed valve are located. A discharge pipe and a discharge valve are located at the bottom. A porous filter plate is located in the middle of the reaction vessel, dividing the inner cavity of the reaction vessel into upper and lower parts. An upper heat exchange jacket is located outside the upper cavity, and a lower heat exchange jacket is located outside the lower cavity. The pore size of the porous filter plate is smaller than the minimum particle size of the crystallized particles. This invention achieves the goal of performing extraction, crystallization, and filtration in the same reaction vessel, which can greatly save equipment investment and space requirements, and also reduce losses and pollution caused by material transfer in traditional processes.

Description

Technical Field

[0001] This invention relates to the field of separation and purification technology, specifically to a three-in-one operation device and method for extraction, crystallization, and filtration. Background Technology

[0002] Extraction, crystallization, and filtration are common separation and purification methods in chemical separation operations, and these three technologies often need to be performed in sequence to complete the purification of substances. The traditional method involves placing the material in an extraction vessel for extraction and separation, then transferring the phase to be crystallized to a crystallizer for crystallization, and finally transferring the crystallized material to a filtration device for filtration to obtain a high-purity crystalline product. This entire process involves multiple pieces of equipment and transfer operations, resulting in large equipment footprints, cumbersome operation, susceptibility to system contamination, and potential blockage of valves and pipelines due to crystallization.

[0003] Currently, people have recognized the shortcomings of separate operations and have proposed corresponding solutions. For example, Chinese patent CN212594118U discloses a multi-functional tank that can perform extraction, separation, concentration, crystallization, and filtration. It includes a multi-functional tank, a jacket, a bottom valve, a glass tube, a filter, a storage tank, a sight glass, an eyepiece, an inlet pipe, a heat exchanger, a recovery tank, and a dripping device. This patent integrates multiple operating processes such as extraction, separation, concentration, crystallization, and filtration into a single multi-functional tank. However, the filtration operation still needs to be transferred to the filter, and the problem of the series of operations of extraction, crystallization, and filtration is not effectively solved. Summary of the Invention

[0004] The purpose of this invention is to provide a device and method for extraction, crystallization and filtration that can be performed sequentially in the same device, thereby efficiently separating and purifying chemical products.

[0005] The technical solution adopted in this invention is:

[0006] An extraction, crystallization, and filtration integrated operation device includes a reaction vessel. The reaction vessel is equipped with an upper head cover plate, a feed pipe and a feed valve on the upper head cover plate, and a discharge pipe and a discharge valve at the bottom. A porous filter plate is provided in the middle part of the reaction vessel, which divides the inner cavity of the reaction vessel into upper and lower parts. An upper heat exchange jacket is provided on the outside of the upper cavity, and a lower heat exchange jacket is provided on the outside of the lower cavity. The pore size of the porous filter plate is smaller than the minimum particle size of the crystallized particles.

[0007] Furthermore, the temperature inside the upper heat exchange jacket is controlled by temperature control system A, and the temperature inside the lower heat exchange jacket is controlled by temperature control system B.

[0008] Furthermore, the reactor is equipped with an interface meter for measuring the interface between two phases.

[0009] A method for combining extraction, crystallization, and filtration, using any of the aforementioned combined extraction, crystallization, and filtration equipment, specifically includes the following steps:

[0010] 1) Close the bottom discharge valve and open the feed valve. The material containing the extraction solvent enters the reactor through the feed pipe and is allowed to settle and separate into layers.

[0011] 2) After the stratification is completed, the material in the upper cavity is crystallized;

[0012] 3) After crystallization, open the bottom discharge valve. The liquid solvent and other uncrystallized components flow out of the reactor, while the solid crystal particles in the upper chamber are retained on the porous filter plate.

[0013] 4) After filtration, open the upper end cap to remove the solid crystal particles, or heat the solid crystal particles to melt them and then discharge them from the bottom discharge valve.

[0014] Furthermore, step 4) also includes a step of further perspiration or solvent washing of the solid crystal particles after filtration.

[0015] Furthermore, in step 1), the two-phase interface is controlled to be located above the porous filter plate by adding or removing part of the solvent.

[0016] Furthermore, in step 2), the crystallization operation can be carried out by cooling, heating to evaporate the solvent, or adding seed crystals.

[0017] Furthermore, in step 3), the filtration operation is performed under positive or negative pressure.

[0018] The beneficial effects of this invention are as follows: This invention achieves the goal of carrying out extraction, crystallization, and filtration in the same reaction vessel, which can greatly save equipment investment and space requirements, and also reduce losses and pollution caused by material transfer in traditional processes. At the same time, by controlling the two-phase interface on the porous filter plate, crystallization is prevented from occurring within the porous filter plate, greatly improving the performance and lifespan of the porous filter plate and reducing usage and maintenance costs. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of an extraction, crystallization, and filtration integrated operation device according to the present invention.

[0020] Figure 2 This is a schematic diagram of the temperature control system of the heat exchange jacket of the present invention. Detailed Implementation

[0021] The present invention will be further illustrated below with specific examples to facilitate understanding of the invention, but this does not limit the invention.

[0022] Example 1

[0023] See Figure 1 This embodiment provides a three-in-one extraction, crystallization, and filtration device, including a reaction vessel 10. The reaction vessel is equipped with an upper end cap 11, on which a feed pipe 12 and a feed valve 13 are provided. A discharge pipe 14 and a discharge valve 15 are provided at the bottom. A porous filter plate 16 is provided in the middle of the reaction vessel 10, dividing the inner cavity of the reaction vessel into upper and lower parts. An upper heat exchange jacket 17 is provided outside the upper cavity, and a lower heat exchange jacket 18 is provided outside the lower cavity. The pore size of the porous filter plate 16 is smaller than the minimum particle size of the crystallized particles. An interface gauge 19 is provided on the upper end cap 11 for measuring the interface between the two phases. The upper heat exchange jacket 17 is controlled by a temperature control system A, and the lower heat exchange jacket 18 is controlled by a temperature control system B.

[0024] In practice, the reactor 10 can be mounted on the operating platform using a support. The pore size of the porous filter plate 16 can be selected according to the grain size of the crystalline material. The porous filter plate 16 is freely supported within the reactor 10 by its own weight. The porous filter plate 16 can be removed from the reactor by opening the upper head cover 11. The feed pipe 12 can be used for feeding or for connecting to the pressurization system during filtration. The discharge pipe 14 can be used for discharging or for connecting to the vacuum system during filtration. The pressurization system can be a pressurizing fan, and the vacuum system can be a vacuum pump. Both the pressurization system and the vacuum system are existing technologies. The upper heat exchange jacket 17 and the lower heat exchange jacket 18 are not connected. Both the upper heat exchange jacket 17 and the lower heat exchange jacket 18 are equipped with heat exchange medium inlet pipes and heat exchange medium outlet pipes. The heat exchange medium inlet pipe and heat exchange medium outlet pipe of the upper heat exchange jacket 17 are connected to the temperature control system A. The temperature control system A controls the heating and cooling of the heat exchange medium in the upper heat exchange jacket 17. The heat exchange medium inlet pipe and heat exchange medium outlet pipe of the lower heat exchange jacket 18 are connected to the temperature control system B, and the temperature control system B controls the heating and cooling of the heat exchange medium in the lower heat exchange jacket 18.

[0025] Temperature control system A and temperature control system B are existing technologies. A detailed explanation will be provided using temperature control system B as an example. (See attached document.) Figure 2The temperature control system B includes a jacketed water inlet pipe connected to the heat exchange medium inlet pipe, a jacketed water outlet pipe connected to the heat exchange medium outlet pipe, a water pump 22, and a heat exchanger 21. The jacketed water inlet pipe is connected to an external tap water pipe via a tee pipe and a valve, and the other end is connected to the inlet pipe of the heat exchanger 21. The inlet pipe of the heat exchanger 21 is connected to the outlet pipe of the water pump 22. The jacketed water outlet pipe is connected to a drain outlet via a tee pipe and a valve, and the other end is connected to the inlet pipe of the water pump 22. The heat exchange medium of the heat exchanger 21 is steam or cooling water.

[0026] Example 2

[0027] This embodiment provides a method for performing a three-in-one operation of extraction, crystallization, and filtration using the equipment described in Embodiment 1, including the following steps:

[0028] 1) Set the temperature of the upper and lower chambers of reactor 10 to be above the crystallization temperature;

[0029] 2) Close the bottom discharge valve 15 and open the feed valve 13. Input the pre-mixed material A containing the substance P to be extracted, crystallized and purified into the reactor 10 through the feed pipe 12. Let it stand and separate into an upper layer B and a lower layer C. Use the interface meter 19 to determine that the interface between phases B and C is above the porous filter plate 16. If the interface is lower than the porous filter plate 16, an appropriate amount of solvent can be added through the feed pipe 12. If the interface is significantly higher than the porous filter plate 16, the interface can be appropriately lowered through the discharge valve 15.

[0030] 3) After the sedimentation and layering are completed, the temperature of the upper layer B is lowered to below the melting point of the substance P to be extracted, crystallized and purified, and crystallization is carried out; the temperature of the lower layer C is kept above the melting point of the substance P to be extracted, crystallized and purified, to prevent some substance P from crystallizing and precipitating out in the lower layer C during the filtration operation.

[0031] 4) After crystallization is complete, open the bottom discharge valve 15 to release the liquid solvent in the lower layer C and the uncrystallized liquid in the upper layer B. The upper layer B can be heated appropriately to induce crystal sweating, or cleaned with solvent. Filtration can be performed under positive or negative pressure to accelerate the filtration process.

[0032] 5) After the filtration operation is completed, the upper cover plate 11 can be opened to directly remove the crystal from the upper layer B, or the temperature of the upper layer B can be increased so that the crystal melts and is released from the bottom.

[0033] Example 3

[0034] Using the method described in Example 2, taking the extraction and crystallization of dioxane as an example, the technical effects of the present invention are further illustrated.

[0035] 4 kg of p-dioxanone (97% purity) and 1 kg of chloroform were thoroughly mixed at 40°C. The mixture was poured into reactor 10, and the temperature inside reactor 10 was maintained at 40°C. The material was allowed to settle and separate into layers in the reactor. After separation, the interface between the two phases was approximately 5 cm above the porous filter plate 16. After separation, the holding temperature of the upper layer B was lowered, controlling the cooling rate at 0.2°C / min, until the temperature reached 24°C, at which point crystallization began, and this temperature was maintained for 4 hours. After crystallization, the bottom discharge valve 15 was opened, and the discharge rate was controlled to first discharge chloroform, followed by the uncrystallized, low-concentration p-dioxanone. The temperature of the upper layer B was increased by 1°C to allow the crystals to sweat. After sweating, the upper end cover 11 was opened, and approximately 2 kg of p-dioxanone crystals (99.5% purity) were directly removed from the top. By combining extraction and crystallization using a three-in-one extraction, crystallization, and filtration device, a high-purity p-dioxanone product was readily obtained.

[0036] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications are also within the protection scope of the present invention.

Claims

1. A method for combining extraction, crystallization, and filtration, characterized in that, Use the following operating equipment. The operating equipment includes a reactor, which is equipped with an upper head cover plate, a feed pipe and a feed valve on the upper head cover plate, a discharge pipe and a discharge valve at the bottom, and a porous filter plate in the middle of the reactor. The porous filter plate divides the reactor cavity into upper and lower parts. An upper heat exchange jacket is provided on the outside of the upper cavity, and a lower heat exchange jacket is provided on the outside of the lower cavity. The pore size of the porous filter plate is smaller than the minimum particle size of the crystallized particles. The operation method includes the following steps: 1) Close the bottom discharge valve and open the feed valve. The material containing the extraction solvent enters the reactor through the feed pipe and is allowed to settle and separate into layers. 2) After the stratification is completed, the material in the upper cavity is crystallized; 3) After crystallization, open the bottom discharge valve. The liquid solvent and other uncrystallized components flow out of the reactor, while the solid crystal particles in the upper chamber are retained on the porous filter plate. 4) After filtration, open the upper end cap to remove the solid crystal particles, or heat the solid crystal particles to melt them and then discharge them from the bottom discharge valve. In step 1), the two-phase interface is controlled to be located above the porous filter plate by adding or removing part of the solvent.

2. The extraction, crystallization, and filtration combined operation method according to claim 1, characterized in that, Step 4) also includes a step of further perspiration or solvent washing of the solid crystal particles after filtration.

3. The extraction, crystallization, and filtration combined operation method according to claim 1, characterized in that, In step 2), the crystallization operation can be carried out by cooling, heating to evaporate the solvent, or adding seed crystals.

4. The extraction, crystallization, and filtration combined operation method according to claim 1, characterized in that, In step 3), the filtration operation is performed under positive or negative pressure.

5. The extraction, crystallization, and filtration combined operation method according to claim 1, characterized in that, The temperature inside the upper heat exchange jacket is controlled by temperature control system A, and the temperature inside the lower heat exchange jacket is controlled by temperature control system B.

6. The method for combining extraction, crystallization, and filtration according to claim 1, characterized in that, An interface meter is installed on the reactor to measure the interface between two phases.

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