Device for efficiently preparing monochlorodifluoromethane by using fluorination reactor
By introducing a built-in pipeline mixer and a jacket structure into the fluorination reactor, heat and mass transfer are enhanced, the problems of poor heat transfer and catalyst entrainment are solved, and efficient and stable difluorochloromethane preparation and long-term operation are achieved.
Patent Information
- Application Number
- CN202422445160.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-10
- Publication Date
- 2025-09-26
- Estimated Expiration
- 2034-10-10
AI Technical Summary
Existing industrial fluorination reactors have problems such as poor heat transfer, easy catalyst entrainment, reactor corrosion, and pipeline blockage, resulting in low reaction efficiency and system instability.
A fluorination reactor is used, including a reactor body and a reaction reflux tower, with a built-in pipeline mixer and a jacket structure, to enhance heat and mass transfer effects, and high-purity difluorochloromethane is obtained through a post-processing process.
Efficient and stable preparation of difluorochloromethane was achieved, the problems of poor heat transfer and catalyst entrainment were solved, and the reaction rate and the long-term operation capability of the system were improved.
Smart Images
Figure CN223381573U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a device for preparing chlorodifluoromethane, in particular to a device for efficiently preparing chlorodifluoromethane by utilizing a fluorination reactor. Background Art
[0002] Chlorodifluoromethane (R22) is a colorless liquefied gas that is extremely destructive to the atmospheric ozone layer and is commonly used as a refrigerant and a raw material for tetrafluoroethylene. Currently, industrial fluorination reactions are primarily divided into two methods: gas-phase fluorination and liquid-phase fluorination. Gas-phase fluorination is primarily carried out in fixed-bed reactors, using metal oxides such as aluminum and cadmium as catalysts. Liquid-phase fluorination is primarily carried out in kettle reactors, using antimony pentachloride as the catalyst. Kettle reactors are classified into two types: stirred and unstirred. While stirred kettle reactors can reduce investment and energy consumption, increase conversion rates, lower temperatures and pressures, and produce fewer impurities, stirred anhydrous hydrogen fluoride can also rub against and scour the reactor walls, leading to significant corrosion. This can easily lead to reactor perforation, material leakage, and environmental pollution. Unstirred kettle reactors also suffer from poor heat transfer. In addition, in liquid-phase reactions, catalysts and anhydrous hydrogen fluoride are easily carried out of the reactor by reaction products, which reduces reaction activity and increases material consumption. At the same time, the entrained acidic substances enter subsequent processes, causing corrosion and leakage. The entrained catalysts are easily accumulated in the pipeline, causing pipeline blockage. Utility Model Content
[0003] The utility model provides a device for efficiently preparing difluorochloromethane by utilizing a fluorination reactor, which can not only obtain high-purity difluorochloromethane but also enhance the heat and mass transfer effects during the preparation process, increase the reaction rate, and make the reaction system efficient and stable.
[0004] The utility model adopts the following technical scheme: a device for efficiently preparing difluorochloromethane by utilizing a fluorination reactor, which comprises a fluorination reactor, an HCL distillation tower, a water washing tower, an alkali separator, a difluorochloromethane distillation tower, a difluorochloromethane tower condenser, a trifluoromethane distillation tower and a difluorochloromethane storage tank, wherein the fluorination reactor comprises a reactor body and a reaction reflux tower, a catalyst feed port, a material feed port II and a material feed port III are sequentially arranged on one side of the reactor body from top to bottom, a built-in pipeline mixer is arranged at the bottom of the reactor body, the catalyst feed port, the material feed port II and the material feed port III are all connected with the built-in pipeline mixer, a discharge port I provided at the top of the reactor body is connected with an inlet I of the reaction reflux tower, a built-in condenser is installed in the inner cavity of the reaction reflux tower, the feed port of the built-in condenser corresponds to the inlet of the reaction reflux tower, and the discharge port of the built-in condenser extends out of the reaction reflux tower. The flow tower is connected to the inlet II on the side of the HCL distillation tower. The discharge port II on the top of the HCL distillation tower is connected to the inlet III on the side of the water washing tower through a collector and a cooler in turn. The top of the water washing tower is provided with a water inlet and an acid outlet. The bottom outlet of the water washing tower is connected to the inlet IV on the side of the alkali separator in turn through a mixing pump and an alkali cooler. The top outlet of the alkali separator is connected to a condenser and a decanter in turn. The discharge port III at the bottom of the decanter is connected to the difluoro- The inlet V on the side of the chloromethane distillation tower is connected, the discharge port IV on the top of the difluorochloromethane distillation tower is connected to the inlet VI on the side of the trifluoromethane distillation tower through the difluorochloromethane condenser I, the difluorochloromethane reflux tank and the difluorochloromethane reflux pump in sequence, and the discharge port V at the bottom of the trifluoromethane distillation tower is connected to the difluorochloromethane storage tank through the difluorochloromethane condenser II, the difluorochloromethane intermediate tank and the difluorochloromethane delivery pump in sequence.
[0005] Furthermore, both ends of the pipeline I are connected to the discharge port I on the top of the reactor body and the inlet I of the reaction reflux tower respectively through flanges.
[0006] Furthermore, one side of the reaction reflux tower is provided with a thermometer sleeve port and a pressure detection port in sequence from top to bottom.
[0007] Furthermore, a probe tube I is installed in the catalyst feed port, one end of the probe tube I extends into the catalyst feed port, and the other end of the probe tube I is located in the reactor body and is connected to the built-in pipeline mixer. A probe tube II is installed in the material feed port II, one end of the probe tube II extends into the material feed port II, and the other end of the probe tube II is located in the reactor body and is connected to the built-in pipeline mixer. A probe tube III is installed in the material feed port III, one end of the probe tube III extends into the material feed port III, and the other end of the probe tube III is located in the reactor body and is connected to the built-in pipeline mixer.
[0008] Furthermore, the built-in pipeline mixer is configured as a spiral plate pipeline mixer, a twill plate pipeline mixer, a flow channel pipeline mixer or an enhanced pipeline mixer.
[0009] Furthermore, the reactor body is provided with a jacket on the outside, a deflection baffle is provided inside the jacket, a steam inlet is provided on the side of the upper part of the jacket, and a condensed water outlet is provided on the lower part of the jacket.
[0010] Furthermore, the upper part of the inner cavity of the reaction reflux tower is a combination of a sieve plate and a downcomer, the sieve plate and the downcomer are spaced apart, and the lower part of the inner cavity of the reaction reflux tower is built with fillers.
[0011] Furthermore, the material of the reactor body is carbon steel, 316L stainless steel or Montell alloy, the reaction pressure in the reactor body is 1.5-1.8 MPa, and the reaction temperature is 60-90°C.
[0012] Furthermore, the reaction reflux tower is located on the upper part of the reactor body, and a reflux pipe is provided between the reaction reflux tower and the reactor body.
[0013] After adopting the above technical scheme, the utility model can achieve enhanced mixing, heat transfer and separation effects; and after post-processing steps including condensation, separation, impurity removal and distillation, high-purity difluoromonochloromethane can be obtained. The fluorination reactor adopted by the utility model includes a reactor body and a reaction reflux tower, a catalyst feed port, a material feed port II and a material feed port III of the reactor body, and a built-in pipeline mixer at the bottom of the reactor body. The catalyst feed port, the material feed port II and the material feed port III 44 are all connected to the built-in pipeline mixer. In this way, not only can the heat transfer and separation effects of the fluorination reactor be enhanced through structural modification, but also the built-in pipeline mixer is used to fully mix the reaction raw materials, effectively improving the problem of small material contact area, increasing the contact area between the reactants, enhancing the heat and mass transfer effect, making the reaction more complete, and thus improving the reaction rate. In addition, the reactor structure can efficiently produce difluoromonochloromethane and can also be applied to the reaction preparation of other refrigerants, solving the problems of reduced catalyst catalytic activity, pipeline blockage, corrosion caused by the entrainment of the reactor catalyst and anhydrous hydrogen fluoride, and making the reaction system efficient, stable and long-term operation. The catalyst feed port of the present invention is connected to the built-in pipeline mixer via a probe tube I, the material feed port II is connected to the built-in pipeline mixer via a probe tube II, and the material feed port III is connected to the built-in pipeline mixer via a probe tube III. This allows the probe tubes to detect parameters such as temperature and pressure, thereby improving the effect of the mixing reaction. The reactor body of the present invention is externally jacketed, with a baffle disposed within the jacket. A steam inlet is disposed on the side of the upper jacket, and a condensate outlet is disposed at the lower jacket, thereby improving heat transfer efficiency. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.
[0015] Figure 1 It is a structural diagram of the present utility model. DETAILED DESCRIPTION
[0016] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more precise definition of the protection scope of the present invention.
[0017] exist Figure 1In the present invention, a device for efficiently preparing difluorochloromethane using a fluorination reactor is provided, which includes a fluorination reactor, an HCL distillation tower 2, a water washing tower 3, an alkali separator 4, a difluorochloromethane distillation tower 5, a difluorochloromethane tower condenser 6, a trifluoromethane distillation tower 7 and a difluorochloromethane storage tank 8. The fluorination reactor of this embodiment is equipped with a weighing module. The fluorination reactor includes a reactor body 1 and a reaction reflux tower 9. A catalyst feed port 42, a material feed port II 43 and a material feed port III 44 are sequentially provided on one side of the reactor body 1 from top to bottom. A built-in pipeline mixer 47 is provided at the bottom of the reactor body 1. The catalyst feed port 42, the material feed port II 43 and the material feed port III 44 are all connected to the built-in pipeline mixer 47. The discharge port Ⅰ12 provided at the top of the reactor body 1 is connected to the inlet Ⅰ13 of the reaction reflux tower 9. The inner cavity of the reaction reflux tower 9 is equipped with a built-in condenser 14. The feed port of the built-in condenser 14 corresponds to the inlet of the reaction reflux tower 9. The discharge port of the built-in condenser 14 extends out of the reaction reflux tower 9 and is connected to the inlet Ⅱ15 on the side of the HCL distillation tower 2. The discharge port Ⅱ16 at the top of the HCL distillation tower 2 is connected to the inlet Ⅲ19 on the side of the water washing tower 3 through the collector 17 and the cooler 18. The top of the water washing tower 3 is provided with a water inlet 20 and an acid outlet 21. The bottom outlet 54 of the water washing tower 3 is connected to the inlet Ⅳ24 on the side of the alkali separator 4 through the mixing pump 22 and the alkali cooler 23 in sequence. The top outlet 25 of the alkali separator 4 is connected in sequence with the condenser 17 and the cooler 18. 26 and decanter 27, the discharge port III 28 at the bottom of the decanter 27 is connected to the inlet V 29 on the side of the difluorochloromethane distillation tower 5, the discharge port IV 30 at the top of the difluorochloromethane distillation tower 5 is connected to the inlet VI 34 on the side of the trifluoromethane distillation tower 7 in sequence through the difluorochloromethane condenser I 31, the difluorochloromethane reflux tank 32 and the difluorochloromethane reflux pump 33, the discharge port V 35 at the bottom of the trifluoromethane distillation tower 7 is connected to the difluorochloromethane storage tank 8 in sequence through the difluorochloromethane condenser II 36, the difluorochloromethane intermediate tank 37, the difluorochloromethane delivery pump 38, and the two ends of the pipeline I of this embodiment are connected to the discharge port I 12 at the top of the reactor body 1 and the inlet I 13 of the reaction reflux tower 9 by flanges 39. , the reaction reflux tower 9 of this embodiment is provided with a thermometer sleeve port 40 and a pressure detection port 41 on one side from top to bottom in sequence, and the thermometer sleeve port 40 and the pressure detection port 41 can detect the temperature and pressure of the reaction reflux tower 9. The catalyst feed port 42 of this embodiment is installed with a probe tube I 45, one end of the probe tube I 45 extends into the catalyst feed port 42, and the other end of the probe tube I 45 is located in the reactor body 1 and is connected to the built-in pipeline mixer 47. The material feed port II 43 is installed with a probe tube II 46, one end of the probe tube II 46 extends into the material feed port II 43, and the other end of the probe tube II 46 is located in the reactor body 1 and is connected to the built-in pipeline mixer 47. The material feed port III 44 is installed with a probe tube III 48.One end of the probe tube III 48 extends into the material feed port III 44, and the other end of the probe tube III 48 is located in the reactor body 1 and is connected to the built-in pipeline mixer 47. The built-in pipeline mixer 47 of this embodiment is set as a spiral-plate pipeline mixer, a twill-plate pipeline mixer, a flow channel pipeline mixer or an enhanced pipeline mixer. This embodiment preferably uses a spiral-plate pipeline mixer. The reactor body 1 of this embodiment is provided with a jacket 49 on the outside, a deflection baffle is provided inside the jacket 49, a steam inlet 50 is provided on the upper side of the jacket 49, and a condensate outlet 51 is provided on the lower part of the jacket 49. The upper part of the inner cavity of the reaction reflux tower 9 of this embodiment is a sieve plate 52 and a downcomer 10 combination, the sieve plate 52 and the downcomer 10 are spaced apart, and the lower part of the inner cavity of the reaction reflux tower 9 is equipped with a filler 11. The material of the reactor body 1 of this embodiment is carbon steel, 316L stainless steel or Montell alloy material. The material of the reactor body (1) preferably used in this embodiment is 316L stainless steel. The reaction pressure in the reactor body 1 is 1.5-1.8MPa, and the reaction temperature is 60-90℃. The reaction pressure in the reactor body 1 is preferably 1.8MPa, and the reaction temperature is 80℃. The reaction reflux tower 9 of this embodiment is located at the upper part of the reactor body 1, and a reflux pipe 53 is provided between the reaction reflux tower 9 and the reactor body 1.
[0018] The working process of the utility model is as follows: first, the antimony pentachloride catalyst is introduced into the reactor body 1 through the catalyst feed port 42, and then the raw materials CHCL3 and anhydrous hydrogen fluoride are respectively introduced through the material feed port II 43 and the material feed port III 44, and the feed amount is measured, and the antimony pentachloride catalyst, CHCL3 and anhydrous hydrogen fluoride are subjected to fluorination reaction in the built-in pipeline mixer 47, and are directly gasified under the reaction temperature condition. The reaction temperature is controlled at 70°C, and CHCL3 and anhydrous hydrogen fluoride are fully contacted with the antimony pentachloride catalyst in a bubbling form to react. The reaction pressure is controlled at 1.7 MPa to obtain the reaction product. The reaction products R21, difluorochloromethane, R23, HCL, unreacted AHF, CHCl3, and the entrained catalyst are all fed into the reaction reflux tower 9 at the upper part of the reactor body 1. Based on the separation principle, the materials are separated by the combination of the sieve plate 52 and the downcomer 10, so that the catalyst, most of the CHCl3, AHF, R21 and other heavy components are returned to the reactor body 1 through the reflux pipe 53 to continue the reaction. The light components mainly composed of difluorochloromethane and HCL are cooled and extracted by the built-in condenser 14 of the reaction reflux tower 9, and then enter the HCL distillation tower 2 to continue the separation of difluorochloromethane and HCL. The difluorochloromethane separated after the HCl distillation separation and the capture operation of the collector 17 and the cooling of the cooler 18, the tower pressure of the HCL distillation tower 2 is controlled at 1.55~1.8MPa, the tower bottom temperature is controlled at 20~50℃, the tower pressure of the HCL distillation tower 2 in this embodiment is controlled at 1.8MPa, the tower bottom temperature is controlled at 50℃, the separated difluorochloromethane is extracted by the water washing tower 3, and after phase separation, it is pumped into the alkali separator 4 through the mixing pump 22 to remove acidic substances, wherein the tower pressure of the water washing tower 3 is controlled at 1.4~1.6MPa, the tower pressure of the water washing tower 3 in this embodiment is controlled at 1 .5MPa; After the treatment of removing acidic substances, the difluorochloromethane is separated by the condenser 26 and treated in the decanter 27. The crude difluorochloromethane enters the difluorochloromethane distillation tower 5 for refining, wherein the pressure of the decanter 27 is controlled at 1.4-1.6MPa. In this embodiment, the pressure of the decanter 27 is controlled at 15MPa. The tower pressure of the difluorochloromethane distillation tower 5 is controlled at 1.0-1.5MPa, the tower bottom temperature is controlled at 30-60°C, the tower top reflux liquid temperature is -10-10°C, the reflux ratio is controlled at 1.5:1-4:1, and the tower pressure of the difluorochloromethane distillation tower 5 is controlled at 1.5MPa, the tower bottom temperature is controlled at 50℃, the tower top reflux liquid temperature is 1℃, and the reflux ratio is controlled at 4:1; the difluorochloromethane after distillation flowing out of the top of the difluorochloromethane distillation tower 5 is condensed for the first time in the difluorochloromethane condenser I 31 and flows into the difluorochloromethane reflux tank 32, and is pumped into the trifluoromethane distillation tower 7 by the difluorochloromethane reflux pump 33, and enters the trifluoromethane distillation tower 7 to remove light components, which may be R23 and non-condensable gases. The finished difluorochloromethane flowing out of the bottom of the trifluoromethane distillation tower 7 is After condensation in difluorochloromethane condenser II 36, the product enters difluorochloromethane intermediate tank 37 and is transported to difluorochloromethane storage tank 8 via difluorochloromethane delivery pump 38. The purity of the finished difluorochloromethane obtained in this process reaches over 99.99%. The pressure of trifluoromethane distillation tower 7 is controlled at 1.0-1.5 MPa, the bottom temperature at 30-50°C, and the reflux ratio at 2:1-4:1. In this embodiment, the pressure of trifluoromethane distillation tower 7 is controlled at 1.5 MPa, the bottom temperature at 50°C, and the reflux ratio at 4:1.
[0019] Product process control and finished product testing are obtained by gas chromatography analysis. The analysis results of the finished product R22 are shown in Table 1:
[0020] Table 1 Product quality analysis results:
[0021] Serial number Indicator name Indicator unit High purity grade Raw material grade 1 Appearance and smell Colorless, transparent and odorless Colorless, transparent and odorless 2 purity % ≥ 99.98 ≥ 99.95 3 moisture PPm ≤ 5 ≤ 10 4 Acidity (in HCL) PPm ≤ 1 ≤ 1 5 Evaporation residue PPm ≤ 10 ≤ 15 6 oxygen content PPm ≤ 30 ≤ 50 7 Carbon dioxide content PPm ≤ 10 ≤ 100 8 Non-condensable gases in the gas phase % ≤ 0.3 ≤0.5 9 Chloride (CL) test / / .
[0022] Without limitation to this, any changes or substitutions that are not conceived through creative work should be included in the scope of protection of this utility model. Therefore, the scope of protection of this utility model should be based on the scope of protection defined in the claims.
Claims
1. A device for efficiently preparing difluorochloromethane using a fluorination reactor, characterized in that It comprises a fluorination reactor, an HCL distillation tower (2), a water washing tower (3), an alkali separator (4), a difluorochloromethane distillation tower (5), a difluorochloromethane tower condenser (6), a trifluoromethane distillation tower (7) and a difluorochloromethane storage tank (8). The fluorination reactor comprises a reactor body (1) and a reaction reflux tower (9). A catalyst feed port (42), a material feed port II (43) and a material feed port III (44) are sequentially provided on one side of the reactor body (1) from top to bottom. A built-in pipeline mixer (47) is provided at the bottom of the reactor body (1). The catalyst feed port ( 42), the material feed port II (43) and the material feed port III (44) are all connected to the built-in pipeline mixer (47), the discharge port I (12) provided on the top of the reactor body (1) is connected to the inlet I (13) of the reaction reflux tower (9), the reaction reflux tower (9) is provided with a built-in condenser (14) installed in the inner cavity, the feed port of the built-in condenser (14) corresponds to the inlet of the reaction reflux tower (9), the discharge port of the built-in condenser (14) extends out of the reaction reflux tower (9) and is connected to the inlet II (15) on the side of the HCL distillation tower (2), the top of the HCL distillation tower (2) is connected to the inlet II (15) on the side of the HCL distillation tower (2). The discharge port II (16) is connected to the inlet III (19) on the side of the water washing tower (3) through the collector (17) and the cooler (18). The top of the water washing tower (3) is provided with a water inlet (20) and an acid outlet (21). The bottom outlet (54) of the water washing tower (3) is connected to the inlet IV (24) on the side of the alkali separator (4) through the mixing pump (22) and the alkali cooler (23). The top outlet (25) of the alkali separator (4) is connected to the condenser (26) and the decanter (27) in sequence. The discharge port III (28) at the bottom of the decanter (27) is connected to the difluorochloromethane concentrate. The inlet V (29) on the side of the difluorochloromethane distillation tower (5) is connected, the discharge port IV (30) at the top of the difluorochloromethane distillation tower (5) is connected to the inlet VI (34) on the side of the trifluoromethane distillation tower (7) through the difluorochloromethane condenser I (31), the difluorochloromethane reflux tank (32) and the difluorochloromethane reflux pump (33), and the discharge port V (35) at the bottom of the trifluoromethane distillation tower (7) is connected to the difluorochloromethane storage tank (8) through the difluorochloromethane condenser II (36), the difluorochloromethane intermediate tank (37) and the difluorochloromethane delivery pump (38).
2. The device for efficiently preparing chlorodifluoromethane using a fluorination reactor according to claim 1, characterized in that The two ends of the pipeline I are connected to the discharge port I (12) at the top of the reactor body (1) and the inlet I (13) of the reaction reflux tower (9) respectively through flanges (39).
3. The device for efficiently preparing chlorodifluoromethane using a fluorination reactor according to claim 1, characterized in that One side of the reaction reflux tower (9) is provided with a thermometer sleeve port (40) and a pressure detection port (41) in sequence from top to bottom.
4. The device for efficiently preparing difluorochloromethane using a fluorination reactor according to claim 1, characterized in that The catalyst feed port (42) is provided with a probe tube I (45), one end of which extends into the catalyst feed port (42), and the other end of which is located in the reactor body (1) and communicated with the built-in pipeline mixer (47). The material feed port II (43) is provided with a probe tube II (46), one end of which extends into the material feed port II (43), and the other end of which is located in the reactor body (1) and communicated with the built-in pipeline mixer (47). The material feed port III (44) is provided with a probe tube III (48), one end of which extends into the material feed port III (44), and the other end of which is located in the reactor body (1) and communicated with the built-in pipeline mixer (47).
5. The device for efficiently preparing chlorodifluoromethane using a fluorination reactor according to claim 4, characterized in that The built-in pipeline mixer (47) is configured as a spiral plate pipeline mixer, a twill plate pipeline mixer, a flow channel pipeline mixer or an enhanced pipeline mixer.
6. The device for efficiently preparing chlorodifluoromethane using a fluorination reactor according to claim 1 or 4, characterized in that The reactor body (1) is provided with a jacket (49) on the outside, a deflection baffle is provided inside the jacket (49), a steam inlet (50) is provided on the side of the upper part of the jacket (49), and a condensed water outlet (51) is provided on the lower part of the jacket (49).
7. The device for efficiently preparing chlorodifluoromethane using a fluorination reactor according to claim 1, characterized in that The upper portion of the inner cavity of the reaction reflux tower (9) is a combination of a sieve plate (52) and a downcomer (10), the sieve plate (52) and the downcomer (10) are spaced apart, and a filler (11) is built into the lower portion of the inner cavity of the reaction reflux tower (9).
8. The device for efficiently preparing chlorodifluoromethane using a fluorination reactor according to claim 1, characterized in that The material of the reactor body (1) is carbon steel, 316L stainless steel or Montell alloy. The reaction pressure in the reactor body (1) is 1.5-1.8 MPa, and the reaction temperature is 60-90°C.
9. The device for efficiently preparing chlorodifluoromethane using a fluorination reactor according to claim 1, characterized in that The reaction reflux tower (9) is located at the upper part of the reactor body (1), and a reflux pipe (53) is provided between the reaction reflux tower (9) and the reactor body (1).