Polyimide mother liquor recycling machine

Abstract

The utility model provides a polyimide mother liquor recycling machine, and belongs to the technical field of polyimide. According to the technical scheme, the device comprises a bottom plate, and a filter tank, a distillation retort, a solvent storage tank, a solute precipitation separation box and a solvent collection box are sequentially arranged on the bottom plate through a plurality of supporting columns; the filter tank is communicated to the distillation retort through a pipeline I, the distillation retort is communicated with the solvent storage tank through a pipeline II arranged at the top, the solvent storage tank is communicated to the solvent collection box through a pipeline III, and the distillation retort is communicated to the solute precipitation separation box through a pipeline IV. The polyimide mother liquor recycling device has the advantages that the polyimide mother liquor recycling device is simple in structure and convenient to operate, a plurality of parts used for recycling polyimide mother liquor are integrated on the bottom plate, the labor amount of workers is reduced, and meanwhile the working efficiency is improved.

Description

Technical Field

[0001] This utility model relates to the field of polyimide technology, and more particularly to a polyimide mother liquor recovery machine. Background Technology

[0002] The recovery of polyimide mother liquor generally involves pretreatment, solute recovery, and solvent recovery. Pretreatment includes filtration and separation of solvent and solute. Filtration removes solid impurities from the mother liquor, such as unreacted raw material particles and gel particles generated during polymerization. Then, the solute and solvent are separated by vacuum distillation (if the solvent in the mother liquor has a low boiling point, distillation can be carried out under appropriate temperature and vacuum conditions. For example, for polyimide mother liquor using N-methylpyrrolidone (NMP) as a solvent, NMP has a boiling point of around 202°C; vacuum conditions can lower its boiling point, making it easier to distill out, thus achieving preliminary separation from the polyimide solute). Solute recovery generally uses precipitation, where a precipitant is added to the pretreated mother liquor to precipitate the polyimide. The solvent can be purified by multiple distillations.

[0003] Currently, there is no complete device for polyimide mother liquor recovery that can realize the above-mentioned main steps. Usually, the main components are distributed in different spaces and far apart, which increases the labor intensity of workers. To address this, this application provides a polyimide mother liquor recovery machine that integrates the main recovery steps into one device, thereby improving work efficiency and reducing labor intensity. Utility Model Content

[0004] The purpose of this invention is to provide a polyimide mother liquor recovery machine that is easy to operate and reduces the labor intensity of workers.

[0005] This utility model is achieved through the following measures:

[0006] A polyimide mother liquor recovery machine is characterized by comprising a base plate, on which a filter tank, a distillation tank, a solvent storage tank, a solute precipitation separation tank and a solvent collection tank are sequentially arranged by a plurality of support columns;

[0007] The filter tank is connected to the distillation tank via pipe one. The distillation tank and the solvent storage tank are connected via pipe two located at the top. The solvent storage tank is connected to the solvent collection tank via pipe three. The distillation tank is connected to the solute precipitation separation tank via pipe four. The polyimide mother liquor is first filtered in the filter tank, and then flows into the distillation tank via pipe one. It is heated and distilled in the distillation tank. In this embodiment, the solvent of the polyimide mother liquor is N-methylpyrrolidone (NMP). The boiling point of NMP is about 202°C. Under reduced pressure, its boiling point can be lowered, making it easier to distill out. The gaseous solvent enters the solvent storage tank through pipe two, and then enters the solvent collection tank through pipe three. The solute, i.e., the polyimide liquid, enters the solute precipitation separation tank through pipe four. Then, a precipitant is added to the precipitation separation tank to precipitate the polyimide. The choice of precipitant depends on the chemical structure and properties of polyimide. Specifically, alcohols with low polarity, such as methanol, can be added as precipitants. When methanol is added, the solubility of polyimide decreases, causing it to precipitate in solid form. The precipitate is then collected by filtration to obtain the recovered polyimide. The solvent in the solvent collection tank can be further processed.

[0008] The specific features of this utility model also include:

[0009] The height of the filter tank is higher than the height of the distillation tank and the solvent storage tank, and the height of the distillation tank and the solvent storage tank is higher than the height of the solute precipitation separation tank and the solvent collection tank, respectively. This arrangement facilitates the flow of liquid.

[0010] The distillation vessel includes a vessel body and a heating resistance wire disposed on the inner wall of the vessel body. The heating resistance wire is coiled in a spring shape on the inner wall of the vessel body, and a plug for connecting to a power source is provided on the vessel body.

[0011] The filtration tank is divided into a mother liquor chamber and an impurity collection chamber by an internal partition. A pipeline is installed in the mother liquor chamber and connects to the distillation tank. Sliding grooves are provided on both sides of the mother liquor chamber, close to the partition. Cooperating sliders are slidably installed in the sliding grooves on both sides. A filter plate is installed between the sliders on both sides and slides to cooperate with the inside of the mother liquor chamber. The filter plate is used to filter solid impurities in the mother liquor. A limiting plate is provided on the inner wall in the middle of the mother liquor chamber to support the filter plate.

[0012] On the inner walls of both sides of the filter tank above the partition, there are circular grooves that cooperate with the slider. The circular grooves are connected to the corresponding sliding grooves. The slider is manually or by hooking a wire into the filter hole of the filter plate, and then the filter plate is slid up. Then the slider slides into the circular groove, and then the filter plate is rotated to enter the impurity collection chamber. In this way, the solid impurities remaining on the filter plate will be collected into the impurity collection chamber.

[0013] The solute precipitation separation tank is equipped with a matching receiving box, which is located in the middle of the solute precipitation separation tank. The receiving box has a groove in the middle of the bottom surface of the receiving box, and several leakage holes are provided on the bottom surface of the groove. Several sets of filter grooves leading to the bottom surface of the groove are vertically arranged on the inner wall of the groove.

[0014] A matching sealing plate is slidably disposed within the groove. Several sets of springs are disposed between the sealing plate and the bottom surface of the groove. One end of the spring is fixed to the sealing plate, and the other end of the spring is fixed to the bottom surface of the groove. In the initial state, under the action of the spring, the upper surface of the sealing plate is flush with the bottom surface of the receiving box, sealing the filter tank. When the sealing plate is pressed down with a rod, the filter tank is exposed, and the liquid will enter the bottom surface of the groove from the filter tank, and then enter the lower part of the solute precipitation separation tank through the leakage hole.

[0015] The bottom surface of the receiving box is lined with an industrial filter cloth for filtering solid polyimide. Specifically, industrial filter cloths are commonly used when processing materials containing large quantities of polyimide crystals. Filter cloths are made from various materials, such as polyester fiber and polypropylene fiber. The pore size of these filter cloths can be customized as needed, making them very effective for filtering polyimide crystals. For example, for millimeter-sized polyimide crystals, filter cloths with larger pores (several millimeters) can be selected to increase the filtration speed; while for micron-sized crystals, filter cloths with pores at the micron level are selected.

[0016] During use, a precipitant is added to the solute precipitation separation tank to precipitate the polyimide. Then, by pressing down the sealing plate, the liquid flows into the bottom of the solute precipitation separation tank, thereby retaining the polyimide on the industrial filter cloth for collection. The liquid at the bottom of the solute precipitation separation tank can be further collected and processed. Specifically, it can be collected into other collection tanks through pipeline five installed on the solute precipitation separation tank.

[0017] The receiving box is provided with vertical plates on both sides, and a handle is provided at the upper end of the vertical plate to rest on the upper end of the side wall of the solute precipitation separation tank. After precipitation is completed, the receiving box is taken out from the solute precipitation separation tank by the handle to collect the fixed polyimide.

[0018] Ball valves are installed on each of the following pipelines for on / off control: pipeline 1, pipeline 2, pipeline 3, and pipeline 4.

[0019] Several sets of casters are provided on the lower side of the base plate.

[0020] Working principle: The polyimide mother liquor is first filtered in the filtration tank, and then flows through the first pipeline into the distillation tank, where it is heated and distilled. In this embodiment, the solvent for the polyimide mother liquor is N-methylpyrrolidone (NMP). The boiling point of NMP is around 202°C. Under reduced pressure, its boiling point can be lowered, making it easier to distill out. The gaseous solvent enters the solvent storage tank through the second pipeline, and then enters the solvent collection tank through the third pipeline. The solute, i.e., the polyimide liquid, enters the solute precipitation separation tank through the fourth pipeline. Then, a precipitant is added to the precipitation separation tank to precipitate the polyimide. The choice of precipitant depends on the chemical structure and properties of polyimide. Specifically, alcohols with low polarity, such as methanol, can be added as precipitants. When methanol is added, the solubility of polyimide decreases, causing it to precipitate in solid form. The solid polyimide remains on the industrial filter cloth. Then, the sealing plate is pressed by the corresponding rod, exposing the filter tank. Liquid enters the bottom of the groove from the filter tank and then flows through the leakage hole into the lower part of the solute precipitation separation tank. Finally, the receiving box is removed from the solute precipitation separation tank by the handle to collect the solid polyimide.

[0021] The beneficial effects of this utility model are as follows: This solution has a simple structure and is easy to operate. It integrates multiple components used for polyimide mother liquor recycling onto the base plate, which reduces the workload of workers and improves work efficiency. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall structure of an embodiment of the present utility model.

[0023] Figure 2 for Figure 1 A magnified view of A in the middle.

[0024] Figure 3 This is an exploded view of the relevant components of the receiving box in an embodiment of this utility model.

[0025] The attached diagram is labeled as follows: 1. Base plate; 2. Filter tank; 3. Filter plate; 4. Pipeline 1; 5. Baffle plate; 6. Impurity collection chamber; 7. Pipeline 2; 8. Distillation tank; 9. Solvent storage tank; 10. Pipeline 4; 11. Pipeline 3; 12. Solvent collection box; 13. Solute precipitation separation box; 14. Receiver box; 15. Slide groove; 16. Circular groove; 17. Handle; 18. Vertical plate; 19. Sealing plate; 20. Groove; 21. Filter tank; 22. Spring. Detailed Implementation

[0026] It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0027] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this utility model and simplifying the description, and 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 a limitation of this utility model. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0028] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0029] To clearly illustrate the technical features of this solution, the following detailed implementation method will be used to explain the solution.

[0030] See Figures 1-3 A polyimide mother liquor recovery machine includes a base plate 1, on which a filter tank 2, a distillation tank 8, a solvent storage tank 9, a solute precipitation separation box 13 and a solvent collection box 12 are arranged sequentially by several support columns.

[0031] The filter tank 2 is connected to the distillation tank 8 via pipe 4. The distillation tank 8 and the solvent storage tank 9 are connected via pipe 7 located at the top. The solvent storage tank 9 is connected to the solvent collection tank 12 via pipe 11. The distillation tank 8 is connected to the solute precipitation separation tank 13 via pipe 10. The polyimide mother liquor is first filtered in the filter tank 2, and then flows into the distillation tank 8 via pipe 4. It is heated and distilled in the distillation tank 8. In this embodiment, the solvent of the polyimide mother liquor is N-methylpyrrolidone (NMP). The boiling point of NMP is about 202°C. Under reduced pressure, its boiling point can be lowered, making it easier to distill out. The gaseous solvent enters the solvent storage tank 9 through pipe 7, and then enters the solvent collection tank 12 through pipe 11. The solute, i.e., the polyimide liquid, enters the solute precipitation separation tank 13 through pipe 10. Then, a precipitant is added to the precipitation separation tank to precipitate the polyimide. The choice of precipitant depends on the chemical structure and properties of polyimide. Specifically, alcohols with low polarity, such as methanol, can be added as precipitants. When methanol is added, the solubility of polyimide decreases, causing it to precipitate in solid form. The precipitate is then collected by filtration to obtain the recovered polyimide. The solvent in the solvent collection tank 12 can be further processed.

[0032] The height of the filter tank 2 is higher than the height of the distillation tank 8 and the solvent storage tank 9. The height of the distillation tank 8 and the solvent storage tank 9 is higher than the height of the solute precipitation separation tank 13 and the solvent collection tank 12, respectively. This arrangement facilitates the flow of liquid.

[0033] The distillation tank 8 includes a tank body and a heating resistance wire disposed on the inner wall of the tank body. The heating resistance wire is coiled on the inner wall of the tank body in the shape of a spring 22. The tank body is provided with a plug for connecting to a power source.

[0034] The filter tank 2 is divided into a mother liquor chamber and an impurity collection chamber 6 by an internal partition 5. A pipeline 4 is installed in the mother liquor chamber and connects to the distillation tank 8. Slide grooves 15 are provided on both sides of the mother liquor chamber. The slide grooves 15 are close to the partition 5. A matching slider is slidably installed in both slide grooves 15. A filter plate 3 is installed between the two sliders and slides in the mother liquor chamber. The filter plate 3 is used to filter solid impurities in the mother liquor. A limiting plate is provided on the inner wall in the middle of the mother liquor chamber to support the filter plate 3.

[0035] The inner walls of both sides of the filter pool 2 above the partition 5 are provided with circular grooves 16 that cooperate with the slider. The circular grooves 16 are connected to the corresponding side sliding grooves 15. The filter plate 3 is manually or by hooking a wire into the filter hole, and then the filter plate 3 is slid up. Then the slider is slid into the circular groove 16. Then the filter plate 3 is rotated so that it enters the impurity collection chamber 6. In this way, the solid impurities left on the filter plate 3 will be collected into the impurity collection chamber 6.

[0036] A matching receiving box 14 is movably installed inside the solute precipitation separation tank 13. The receiving box 14 is located in the middle of the solute precipitation separation tank 13. A groove 20 is provided in the middle of the bottom surface of the receiving box 14. Several leakage holes are provided on the bottom surface of the groove 20. Several sets of filter grooves 21 leading to the bottom surface of the groove 20 are vertically arranged on the inner wall of the groove 20.

[0037] A matching sealing plate 19 is slidably disposed within the groove 20. Several sets of springs 22 are disposed between the sealing plate 19 and the bottom surface of the groove 20. One end of the spring 22 is fixed to the sealing plate 19, and the other end of the spring 22 is fixed to the bottom surface of the groove 20. In the initial state, under the action of the spring 22, the upper surface of the sealing plate 19 is flush with the bottom surface of the receiving box 14, sealing the filter tank 21. When the sealing plate 19 is pressed down with a rod, the filter tank 21 is exposed, and the liquid will enter the bottom surface of the groove 20 from the filter tank 21, and then enter the lower part of the solute precipitation separation tank 13 through the leakage hole.

[0038] The bottom surface of the receiving box 14 is lined with an industrial filter cloth for filtering solid polyimide. Specifically, industrial filter cloths are commonly used for filtration when processing materials containing large quantities of polyimide crystals. Filter cloths are made from various materials, such as polyester fiber and polypropylene fiber. The pore size of these filter cloths can be customized as needed, making them very effective for filtering polyimide crystals. For example, for millimeter-sized polyimide crystals, filter cloths with larger pores (several millimeters) can be selected to increase the filtration speed; while for micron-sized crystals, filter cloths with pores at the micron level are selected.

[0039] During use, a precipitant is added to the solute precipitation separation tank 13 to precipitate the polyimide. Then, the liquid flows to the bottom of the solute precipitation separation tank 13 by pressing down the sealing plate 19, so that the polyimide can be left on the industrial filter cloth for collection. The liquid at the bottom of the solute precipitation separation tank 13 can be further collected and treated. Specifically, it can be collected into other collection tanks through the pipeline 5 set on the solute precipitation separation tank 13.

[0040] The receiving box 14 is provided with vertical plates 18 on both sides. The upper end of the vertical plate 18 is provided with a handle 17, which rests against the upper end of the side wall of the solute precipitation separation tank 13. After precipitation is completed, the receiving box 14 is taken out from the solute precipitation separation tank 13 through the handle 17 to collect the fixed polyimide.

[0041] Ball valves are installed on pipes 1-4, 2-7, 3-11, and 4-10 for on / off control.

[0042] Several sets of casters are provided on the lower side of the base plate 1.

[0043] Working principle: The polyimide mother liquor is first filtered in filter tank 2, and then flows into distillation tank 8 through pipeline 4. It is heated and distilled in distillation tank 8. In this embodiment, the solvent of polyimide mother liquor is N-methylpyrrolidone (NMP). The boiling point of NMP is about 202℃. Under reduced pressure, its boiling point can be lowered, making it easier to distill out. The gaseous solvent enters solvent storage tank 9 through pipeline 7, and then enters solvent collection tank 12 through pipeline 11. The solute, i.e., polyimide liquid, enters solute precipitation separation tank 13 through pipeline 10. Then, a precipitant is added to the precipitation separation tank to precipitate the polyimide. The choice of precipitant depends on the chemical structure and properties of polyimide. Specifically, alcohols with low polarity, such as methanol, can be added as precipitants. When methanol is added, the solubility of polyimide decreases, causing it to precipitate in solid form. The solid polyimide remains on the industrial filter cloth. Then, the sealing plate 19 is pressed by the corresponding rod, and the filter tank 21 is exposed. The liquid enters the bottom of the groove from the filter tank 21 and then enters the lower part of the solute precipitation separation tank 13 through the leakage hole. Finally, the receiving box 14 is removed from the solute precipitation separation tank 13 by the handle 17 to collect the solid polyimide.

[0044] The technical features of this utility model not described can be implemented by or by using existing technology, and will not be repeated here. Of course, the above description is not a limitation of this utility model, and this utility model is not limited to the examples above. Any changes, modifications, additions or substitutions made by those skilled in the art within the scope of this utility model should also be within the protection scope of this utility model.

Claims

1. A polyimide mother liquor recovery machine, characterized in that, Includes a base plate (1), on which a filter tank (2), a distillation tank (8), a solvent storage tank (9), a solute precipitation separation tank (13) and a solvent collection tank (12) are arranged in sequence by several support columns; The filter tank (2) is connected to the distillation tank (8) through pipe one (4). The distillation tank (8) and the solvent storage tank (9) are connected through pipe two (7) set at the top. The solvent storage tank (9) is connected to the solvent collection tank (12) through pipe three (11). The distillation tank (8) is connected to the solute precipitation separation tank (13) through pipe four (10).

2. The polyimide mother liquor recovery machine according to claim 1, characterized in that, The height of the filter tank (2) is higher than the height of the distillation tank (8) and the solvent storage tank (9), and the height of the distillation tank (8) and the solvent storage tank (9) is higher than the height of the solute precipitation separation tank (13) and the solvent collection tank (12), respectively.

3. The polyimide mother liquor recovery machine according to claim 1, characterized in that, The distillation vessel (8) includes a vessel body and a heating resistance wire disposed on the inner wall of the vessel body.

4. The polyimide mother liquor recovery machine according to claim 1, characterized in that, The filter tank (2) is divided into a mother liquor chamber and an impurity collection chamber (6) by an internal partition (5). The mother liquor chamber is provided with a pipeline (4) that connects to the distillation tank (8). Slide grooves (15) are provided on both sides of the mother liquor chamber. The slide grooves (15) are close to the partition (5). Sliding sliders are slidably provided in both sides of the slide grooves (15). A filter plate (3) that slides and cooperates with the inside of the mother liquor chamber is provided between the two sliding sliders.

5. The polyimide mother liquor recovery machine according to claim 4, characterized in that, The filter pool (2) above the partition (5) is provided with circular grooves (16) on both sides of the inner wall that cooperate with the slider. The circular grooves (16) are connected to the corresponding side slide grooves (15).

6. The polyimide mother liquor recovery machine according to claim 1, characterized in that, The solute precipitation separation tank (13) is movably provided with a matching receiving box (14). The receiving box (14) is located in the middle of the solute precipitation separation tank (13). A groove (20) is provided in the middle of the bottom surface of the receiving box (14). Several leakage holes are provided on the bottom surface of the groove (20). Several sets of filter grooves (21) leading to the bottom surface of the groove (20) are vertically provided on the inner wall of the groove (20). A matching sealing plate (19) is slidably disposed in the groove (20). A plurality of springs (22) are disposed between the sealing plate (19) and the bottom surface of the groove (20). One end of the spring (22) is fixed on the sealing plate (19), and the other end of the spring (22) is fixed on the bottom surface of the groove (20).

7. The polyimide mother liquor recovery machine according to claim 6, characterized in that, The bottom surface of the receiving box (14) is covered with an industrial filter cloth for filtering polyimide in solid form.

8. The polyimide mother liquor recovery machine according to claim 7, characterized in that, The receiving box (14) is provided with vertical plates (18) on both sides, and the upper end of the vertical plate (18) is provided with a handle (17) which rests against the upper end of the side wall of the solute precipitation separation box (13).

9. The polyimide mother liquor recovery machine according to claim 1, characterized in that, Ball valves are installed on each of the following pipelines: pipeline 1 (4), pipeline 2 (7), pipeline 3 (11), and pipeline 4 (10).

10. The polyimide mother liquor recovery machine according to any one of claims 1 to 9, characterized in that, Several sets of casters are provided on the lower side of the base plate (1).

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