Phosphorus pentafluoride and hydrogen chloride separation device
By designing a separation device for phosphorus pentafluoride and hydrogen chloride, and using three-stage condensation and high-pressure distillation technology, the problem of difficult separation of hydrogen fluoride, phosphorus pentafluoride and hydrogen chloride mixture in the existing technology has been solved, and efficient utilization of resources and improved economic benefits have been achieved.
Patent Information
- Application Number
- CN202422164532.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-04
- Publication Date
- 2025-06-10
- Estimated Expiration
- 2034-09-04
AI Technical Summary
The mixture of hydrogen fluoride, phosphorus pentafluoride and hydrogen chloride produced during the preparation of lithium hexafluorophosphate is difficult to effectively separate, resulting in waste of resources and reduced economic benefits.
A separation device for phosphorus pentafluoride and hydrogen chloride was designed, and hydrogen fluoride was separated through a third-stage condenser, and phosphorus pentafluoride and hydrogen chloride were separated through a high-pressure distillation tower, and finally hydrogen chloride was made into hydrochloric acid for sale.
It realizes efficient separation of hydrogen fluoride, phosphorus pentafluoride and hydrogen chloride, improves the economic benefits of the product and saves energy.
Smart Images
Figure CN222956153U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a separation device for phosphorus pentafluoride mixed gas, in particular to a separation device for phosphorus pentafluoride and hydrogen chloride. Background Art
[0002] Lithium hexafluorophosphate is a commonly used electrolyte material in liquid lithium-ion batteries. Most of the existing preparations of lithium hexafluorophosphate are achieved as follows. The first step is: phosphorus pentachloride reacts with anhydrous hydrogen fluoride at -20°C to generate an intermediate product, phosphorus pentafluoride and hydrogen chloride. Phosphorus pentafluoride forms a white solid, lithium hexafluorophosphate, with hydrogen chloride at -20°C. When the temperature rises above -10°C, lithium hexafluorophosphate decomposes into phosphorus pentafluoride and hydrogen fluoride again. The second step is: phosphorus pentafluoride reacts with lithium fluoride dissolved in anhydrous hydrogen fluoride to generate lithium hexafluorophosphate. In order to make the reaction sufficient, hydrogen fluoride is usually introduced in excess, which generates a large amount of mixed tail gas of hydrogen fluoride, phosphorus pentafluoride and hydrogen chloride. These mixed gases are toxic and harmful gases and need to be harmlessly treated before being discharged into the atmospheric environment, which not only wastes resources but also reduces economic benefits. Content of the Utility Model
[0003] The purpose of the utility model is to provide a separation device for phosphorus pentafluoride and hydrogen chloride aiming at the above-mentioned defects existing in the prior art. The hydrogen fluoride gas in the mixed gas is first separated by a condenser, and then the mixed gas of phosphorus pentafluoride and hydrogen chloride is separated by pressure rectification, thereby improving the economic benefits of the product.
[0004] A separation device for phosphorus pentafluoride and hydrogen chloride mentioned in the utility model has the following technical solution: it includes a mixed gas buffer (1), a first condenser (2), a second condenser (3), a third condenser (4), a hydrogen fluoride storage tank (5), a compressor (6), a preheater (7), a high-pressure rectification tower (8), a hydrogen chloride condenser (9), a spray tower (10), a hydrochloric acid storage tank (14), a control valve (15), a pressure reducing valve (16), a phosphorus pentafluoride condenser (17), and a phosphorus pentafluoride storage tank (18). The output end of the mixed gas buffer (1) is sequentially connected to the compressor (6) through the first condenser (2), the second condenser (3), and the third condenser (4). The lower shell-side outlets of the first condenser (2), the second condenser (3), and the third condenser (4) are respectively connected to the hydrogen fluoride storage tank (5) through pipelines. The output end of the compressor (6) is connected to the side line of the high-pressure rectification tower (8) through a pipeline and the preheater (7). The lower end of the high-pressure rectification tower (8) is connected to the phosphorus pentafluoride storage tank (18) through the pressure reducing valve (16) and the phosphorus pentafluoride condenser (17). The upper end of the high-pressure rectification tower (8) is connected to the spray tower (10) through the hydrogen chloride condenser (9). The lower end of the spray tower (10) is connected to the hydrochloric acid storage tank (14) through a pipeline and the control valve (15).
[0005] Preferably, the lower side of the above-mentioned spray tower (10) is connected to a buffer water tank (12) through a pipeline. The lower side of the buffer water tank (12) is connected to a spray head (10.1) inside the spray tower (10) through a pipeline and a circulation pump (13). A gas ejection tray (10.2) is provided in the middle inner cavity of the spray tower (10). The gas inlet end of the gas ejection tray (10.2) is connected to the tube side outlet of the hydrogen chloride condenser (9) through a pipeline.
[0006] Preferably, the top of the above-mentioned spray tower (10) is connected to a tail gas processor (11) through a pipeline.
[0007] Preferably, the lower shell side outlets of the above-mentioned first condenser (2), second condenser (3) and third condenser (4) are respectively connected to a hydrogen fluoride storage tank (5) through pipelines. The upper shell side outlet of the first condenser (2) is connected to the lower shell side inlet of the second condenser (3) through a pipeline. The upper shell side outlet of the second condenser (3) is connected to the lower shell side inlet of the third condenser (4) through a pipeline. The upper shell side outlet of the third condenser (4) is connected to the inlet of a compressor (6) through a pipeline.
[0008] Preferably, a first control valve (2.1) is provided at the lower end of the above-mentioned first condenser (2), a second control valve (3.1) is provided at the lower end of the second condenser (3), and a third control valve (4.1) is provided at the lower end of the third condenser (4).
[0009] Preferably, a reboiler (8.1) is provided at the lower end of the above-mentioned high-pressure rectification tower (8), and a jacket is provided on the outside of the high-pressure rectification tower (8).
[0010] Preferably, multiple groups of spray heads (10.1) are provided in the inner cavity of the above-mentioned spray tower (10).
[0011] The beneficial effects of the present utility model are as follows: The present utility model sends a mixed gas of hydrogen fluoride, phosphorus pentafluoride and hydrogen chloride into the first condenser, the second condenser and the third condenser. After three-stage condensation, hydrogen fluoride is fully removed and stored in the hydrogen fluoride storage tank; the remaining mixed gas of phosphorus pentafluoride and hydrogen chloride is pressurized to 20-30 bar by a compressor, and rectified using the different boiling points after pressurization, so that phosphorus pentafluoride and hydrogen chloride can be separated, and then hydrogen chloride is made into hydrochloric acid for external sale, thereby greatly improving economic benefits and saving energy. Description of the Drawings
[0012] Figure 1 is a schematic structural diagram of Embodiment 1 of the present utility model;
[0013] Figure 2 is a schematic structural diagram of Embodiment 2 of the present utility model;
[0014] In the above figure: gas mixture buffer 1, first condenser 2, second condenser 3, third condenser 4, hydrogen fluoride storage tank 5, compressor 6, preheater 7, high-pressure rectifying column 8, hydrogen chloride condenser 9, spray tower 10, tail gas processor 11, buffer water tank 12, circulation pump 13, hydrochloric acid storage tank 14, control valve 15, pressure reducing valve 16, phosphorus pentafluoride condenser 17, phosphorus pentafluoride storage tank 18, first control valve 2.1, second control valve 3.1, third control valve 4.1, reboiler 8.1, spray head 10.1, gas ejection tray 10.2. Detailed implementation mode
[0015] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.
[0016] Example 1, referring to Figure 1 , a phosphorus pentafluoride and hydrogen chloride separation device mentioned in the present invention, includes a gas mixture buffer 1, a first condenser 2, a second condenser 3, a third condenser 4, a hydrogen fluoride storage tank 5, a compressor 6, a preheater 7, a high-pressure rectifying column 8, a hydrogen chloride condenser 9, a spray tower 10, a hydrochloric acid storage tank 14, a control valve 15, a pressure reducing valve 16, a phosphorus pentafluoride condenser 17, and a phosphorus pentafluoride storage tank 18. The output end of the gas mixture buffer 1 is sequentially connected to the compressor 6 through the first condenser 2, the second condenser 3, and the third condenser 4. The lower shell-side outlets of the first condenser 2, the second condenser 3, and the third condenser 4 are respectively connected to the hydrogen fluoride storage tank 5 through pipelines; the output end of the compressor 6 is connected to the side line of the high-pressure rectifying column 8 through a pipeline and a preheater 7. The lower end of the high-pressure rectifying column 8 is connected to the phosphorus pentafluoride storage tank 18 through a pressure reducing valve 16 and a phosphorus pentafluoride condenser 17; the upper end of the high-pressure rectifying column 8 is connected to the spray tower 10 through a hydrogen chloride condenser 9. The lower end of the spray tower 10 is connected to the hydrochloric acid storage tank 14 through a pipeline and a control valve 15.
[0017] Wherein, the lower side of the above-mentioned spray tower 10 is connected to the buffer water tank 12 through a pipeline. The lower side of the buffer water tank 12 is connected to the spray head 10.1 in the inner cavity of the spray tower 10 through a pipeline and a circulation pump 13. A gas ejection tray 10.2 is arranged in the middle inner cavity of the spray tower 10. The air inlet end of the gas ejection tray 10.2 is connected to the tube-side outlet of the hydrogen chloride condenser 9 through a pipeline.
[0018] In addition, the top of the above-mentioned spray tower 10 is connected to the tail gas processor 11 through a pipeline, and the gas that fails to be treated is treated as tail gas and then discharged into the atmosphere.
[0019] In addition, the lower shell-side outlets of the above-mentioned first condenser 2, second condenser 3, and third condenser 4 are respectively connected to a hydrogen fluoride storage tank 5 through pipelines. The upper shell-side outlet of the first condenser 2 is connected to the lower shell-side inlet of the second condenser 3 through a pipeline, the upper shell-side outlet of the second condenser 3 is connected to the lower shell-side inlet of the third condenser 4 through a pipeline, and the upper shell-side outlet of the third condenser 4 is connected to the inlet of a compressor 6 through a pipeline.
[0020] A first control valve 2.1 is provided at the lower end of the above-mentioned first condenser 2, a second control valve 3.1 is provided at the lower end of the second condenser 3, and a third control valve 4.1 is provided at the lower end of the third condenser 4.
[0021] A reboiler 8.1 is provided at the lower end of the above-mentioned high-pressure rectification column 8 to heat the high-pressure rectification column 8. In addition, a sandwich layer is provided on the outside of the high-pressure rectification column 8, and a liquid can be introduced to control the temperature, so as to meet the rectification requirements of different products.
[0022] A plurality of spray heads 10.1 are provided inside the above-mentioned spray tower 10, which can better realize the contact between hydrogen chloride gas and water, and then produce hydrochloric acid.
[0023] When the present utility model is in use, a mixed gas containing hydrogen fluoride, phosphorus pentafluoride, and hydrogen chloride is sent into the first condenser 2, second condenser 3, and third condenser 4 through a mixed gas buffer 1. After three-stage condensation and controlling the temperature below 18 degrees, hydrogen fluoride can be fully removed and stored in the hydrogen fluoride storage tank 5. The remaining mixed gas of phosphorus pentafluoride and hydrogen chloride is then pressurized to 20-30 bar by a compressor and distilled at 20°C - 45°C, and phosphorus pentafluoride and hydrogen chloride can be separated. Phosphorus pentafluoride enters the phosphorus pentafluoride storage tank 18 from the bottom of the high-pressure rectification column 8 through a pressure reducing valve 16 and a phosphorus pentafluoride condenser 17 in a liquid state; the top of the high-pressure rectification column 8 is condensed by a hydrogen chloride condenser 9 and then sent into the spray tower 10. The water in the buffer water tank 12 is continuously sent into the spray heads 10.1 inside the spray tower 10 through a circulation pump 13, thereby gradually increasing the concentration of hydrochloric acid. Then, the control valve 15 is opened to send the qualified hydrochloric acid into the hydrochloric acid storage tank 14 for external sales, thereby improving its economic benefits.
[0024] Example 2, refer to Figure 2, a phosphorus pentafluoride and hydrogen chloride separation device mentioned in the present utility model, includes a mixed gas buffer 1, a first condenser 2, a hydrogen fluoride storage tank 5, a compressor 6, a preheater 7, a high-pressure rectification tower 8, a hydrogen chloride condenser 9, a spray tower 10, a hydrochloric acid storage tank 14, a control valve 15, a pressure reducing valve 16, a phosphorus pentafluoride condenser 17, and a phosphorus pentafluoride storage tank 18. The output end of the mixed gas buffer 1 is connected to the compressor 6 through the first condenser 2. The lower shell-side outlets of the first condenser 2, the second condenser 3, and the third condenser 4 are respectively connected to the hydrogen fluoride storage tank 5 through pipelines. The output end of the compressor 6 is connected to the side line of the high-pressure rectification tower 8 through a pipeline and the preheater 7. The lower end of the high-pressure rectification tower 8 is connected to the phosphorus pentafluoride storage tank 18 through the pressure reducing valve 16 and the phosphorus pentafluoride condenser 17. The upper end of the high-pressure rectification tower 8 is connected to the spray tower 10 through the hydrogen chloride condenser 9. The lower end of the spray tower 10 is connected to the hydrochloric acid storage tank 14 through a pipeline and the control valve 15.
[0025] The difference from Embodiment 1 is:
[0026] The lower shell-side outlet of the above-mentioned first condenser 2 is respectively connected to the hydrogen fluoride storage tank 5 through pipelines, and the upper shell-side outlet is connected to the inlet of the compressor 6 through a pipeline. In this embodiment, the first condenser 2 is used to cool the temperature below 18 degrees, and the hydrogen fluoride in the mixed gas is basically condensed, and then collected in the hydrogen fluoride storage tank 5.
[0027] The above are only the preferred embodiments of the present utility model. Any person skilled in the art may modify the present utility model by using the technical solutions described above or modify it into an equivalent technical solution. Therefore, any simple modification or equivalent transformation made according to the technical solutions of the present utility model all fall within the scope of protection required by the present utility model.
Claims
1. A device for separating phosphorus pentafluoride and hydrogen chloride, characterized in that: The invention comprises a mixed gas buffer (1), a first condenser (2), a second condenser (3), a third condenser (4), a hydrogen fluoride storage tank (5), a compressor (6), a preheater (7), a high-pressure rectification tower (8), a hydrogen chloride condenser (9), a spray tower (10), a hydrochloric acid storage tank (14), a control valve (15), a pressure reducing valve (16), a phosphorus pentafluoride condenser (17), and a phosphorus pentafluoride storage tank (18), wherein the output end of the mixed gas buffer (1) is connected to the compressor (6) via the first condenser (2), the second condenser (3), and the third condenser (4) in sequence, and the first condenser (8) is connected to the compressor (6). (2), the lower shell outlets of the second condenser (3) and the third condenser (4) are respectively connected to the hydrogen fluoride storage tank (5) through pipelines; the output end of the compressor (6) is connected to the side line of the high-pressure distillation tower (8) through a pipeline and a preheater (7), and the lower end of the high-pressure distillation tower (8) is connected to the phosphorus pentafluoride storage tank (18) through a pressure reducing valve (16) and a phosphorus pentafluoride condenser (17); the upper end of the high-pressure distillation tower (8) is connected to the spray tower (10) through a hydrogen chloride condenser (9), and the lower end of the spray tower (10) is connected to the hydrochloric acid storage tank (14) through a pipeline and a control valve (15).
2. The device for separating phosphorus pentafluoride and hydrogen chloride according to claim 1, characterized in that: The lower side of the spray tower (10) is connected to the buffer water tank (12) via a pipeline, and the lower side of the buffer water tank (12) is connected to the spray head (10.1) in the inner cavity of the spray tower (10) via a pipeline and a circulation pump (13). A gas ejection disk (10.2) is provided in the middle inner cavity of the spray tower (10), and the gas inlet end of the gas ejection disk (10.2) is connected to the pipe outlet of the hydrogen chloride condenser (9) via a pipeline.
3. The device for separating phosphorus pentafluoride and hydrogen chloride according to claim 2, characterized in that: The top of the spray tower (10) is connected to the tail gas processor (11) via a pipeline.
4. The device for separating phosphorus pentafluoride and hydrogen chloride according to claim 2 or 3, characterized in that: The lower shell side outlets of the first condenser (2), the second condenser (3) and the third condenser (4) are respectively connected to the hydrogen fluoride storage tank (5) through pipelines, the upper shell side outlet of the first condenser (2) is connected to the lower shell side inlet of the second condenser (3) through a pipeline, the upper shell side outlet of the second condenser (3) is connected to the lower shell side inlet of the third condenser (4) through a pipeline, and the upper shell side outlet of the third condenser (4) is connected to the inlet of the compressor (6) through a pipeline.
5. The device for separating phosphorus pentafluoride and hydrogen chloride according to claim 4, characterized in that: A first control valve (2.1) is provided at the lower end of the first condenser (2), a second control valve (3.1) is provided at the lower end of the second condenser (3), and a third control valve (4.1) is provided at the lower end of the third condenser (4).
6. The device for separating phosphorus pentafluoride and hydrogen chloride according to claim 5, characterized in that: A reboiler (8.1) is provided at the lower end of the high-pressure distillation tower (8), and an interlayer is provided on the outer side of the high-pressure distillation tower (8).
7. The device for separating phosphorus pentafluoride and hydrogen chloride according to claim 2, characterized in that: The inner cavity of the spray tower (10) is provided with a plurality of groups of spray heads (10.1).