Phosphorus pentachloride synthesis reactor, continuous synthesis system and method

Abstract

The invention discloses a phosphorus pentachloride synthesis reactor and a continuous synthesis system and method.The phosphorus pentachloride synthesis reactor comprises a reactor body, a nozzle arranged at the top of the reactor body and at least one nozzle set arranged on the side portion of the reactor body, and each nozzle set comprises at least two nozzles; the distance between the top of the reactor body and the adjacent nozzle group is 3-5 times of the inner diameter of the reactor body; the multiple nozzles are arranged on the reactor body in a layered mode, the distribution uniformity of materials in the space of the reactor body is improved, then the heat exchange effect of the materials and heat exchange media is improved, a high-temperature area in the reactor body is reduced or eliminated, and in some embodiments of the invention, the temperature in the reactor can be controlled within 50-70 DEG C.

Description

Technical Field

[0001] The invention relates to a phosphorus pentachloride synthesis reactor, a continuous synthesis system and a method. Background Art

[0002] Phosphorus pentachloride (PCl5) is an important non-polar compound. It is widely used in chlorinating agents, catalysts, dehydrating agents, etc. in organic synthesis. It can be used as a raw material to prepare chemicals such as chlorophosphonitrile, phosphorus oxychloride, lithium hexafluorophosphate, and to produce chemical fibers. It can also be used as a pharmaceutical intermediate and dye intermediate. At present, with the rise of the new energy battery industry, phosphorus pentachloride is widely used in the production of lithium hexafluorophosphate, etc., a lithium battery electrolyte.

[0003] The synthesis methods of phosphorus pentachloride all use phosphorus trichloride and chlorine as raw materials for reaction, and generally adopt the gas-liquid reaction method of chlorine and liquid phosphorus trichloride. The traditional production process mainly adopts intermittent kettle reaction, as disclosed in patent document CN107117591A, chlorine is introduced into the reactor to carry out chlorination reaction with phosphorus trichloride liquid, and chlorine needs to be introduced until the solution is transformed into a completely dry crystalline product through a paste state, and the finished phosphorus pentachloride is obtained. However, the phosphorus pentachloride product is solid, and as the conversion rate of phosphorus trichloride increases, it becomes increasingly difficult to stir the system, and even difficult to stir. In order to make phosphorus trichloride react as completely as possible, it is generally adopted to introduce excessive chlorine chlorination, and then introduce dry carbon dioxide gas to discharge the residual chlorine after the reaction is completed. However, even so, the content of residual phosphorus trichloride in the product is still high, generally at 0.05% or even more than 0.1%, and the chlorine is not completely discharged, resulting in uneven product particles, strong hygroscopicity, poor fluidity, etc.; in addition, there are problems such as large tail gas emissions and harsh operating environment.

[0004] In recent years, some continuous phosphorus pentachloride production processes have been developed, such as patent document CN116920764A, which is characterized in that phosphorus trichloride is atomized into droplets and then reacts chemically with gaseous chlorine to generate phosphorus pentachloride particles. In order to control the reaction temperature, a large amount of CO2 or N2 is required as a diluent and circulating gas for cooling, resulting in a large reactor volume and difficult system temperature control. Summary of the invention

[0005] The technical problem to be solved by the present invention is to overcome the problems of difficult system temperature control and low product purity in the existing phosphorus pentachloride production, and to provide a phosphorus pentachloride synthesis reactor, a continuous synthesis system and a method. The phosphorus trichloride liquid of the present invention is atomized and regulated and then added in stages, so that the temperature in the reactor is uniformly controlled and the temperature is within the range of 50 to 70 DEG C, and the high temperature zone in the reactor is eliminated, so that the obtained phosphorus pentachloride particles have large diameter and high purity.

[0006] The present invention solves the above technical problems through the following technical solutions:

[0007] The present invention also provides a phosphorus pentachloride synthesis reactor, which comprises a reactor body, a nozzle arranged at the top of the reactor body and at least one nozzle group at the side of the reactor body, each of the nozzle groups comprises at least two nozzles; the distance between the top of the reactor body and the nozzle groups adjacent thereto is 3 to 5 times the inner diameter of the reactor body;

[0008] When the number of the nozzle groups is greater than or equal to 2, the multiple nozzle groups are arranged in sequence from top to bottom along the axis of the reactor; the spacing between adjacent nozzle groups along the axial direction of the reactor body is 2 to 5 times the inner diameter of the reactor body.

[0009] In the present invention, when the nozzle spacing is too small, less than 2 times the inner diameter of the reactor body, the reaction zones corresponding to the two nozzles overlap, the temperature rises significantly, and is not conducive to the formation of solid PCl5; when the nozzle spacing is too large, greater than 5 times the inner diameter of the reactor body, the interval between the reaction zones corresponding to the two nozzles further increases, the cooling effect is not obvious, and the investment increases.

[0010] The present invention improves the uniformity of material distribution in the space of the reactor body by arranging multiple nozzles in layers on the reactor, thereby improving the heat exchange effect between the material and the heat exchange medium (such as cooled circulating gas) and reducing or eliminating the high temperature area in the reactor body.

[0011] In the present invention, the number of nozzles in each nozzle group is preferably an even number, and the nozzles in each nozzle group are symmetrically arranged with the axis of the reactor body as the center. The nozzles in each nozzle group are arranged in pairs, which can further improve the uniformity of material distribution in the space of the reactor body, so that the heat exchange effect in the reactor is better and the occurrence of local high temperature is reduced; the number of nozzles is, for example, 3, 5 or 7.

[0012] In a preferred embodiment of the present invention, the total number of the nozzles is 3, one of which is arranged at the top of the reactor body, and the other two nozzles are horizontally arranged around the side of the reactor body and symmetrically centered on the axis of the reactor body.

[0013] In a preferred embodiment of the present invention, there are 7 nozzles, one of which is arranged at the top of the reactor body, and the remaining six nozzles are grouped in pairs to form three nozzle groups, and the three nozzle groups are arranged in sequence from top to bottom along the axial direction of the reactor body, and the two nozzles of each nozzle group are horizontally arranged around the side of the reactor body symmetrically with the axis of the reactor body as the center, and the projections of the nozzles in the three nozzle groups on the cross section of the reactor body are evenly distributed along the circumference of the reactor body.

[0014] In the present invention, the projections of the nozzles in two adjacent nozzle groups on the cross section of the reactor body are equally spaced along the circumference of the reactor body, and the cross section of the reactor body refers to a surface perpendicular to the axis of the reactor body, thereby further improving the uniformity of the distribution of materials in the space of the reactor body.

[0015] In the present invention, the distance between the nozzle disposed on the top of the reactor body and the nozzle group adjacent thereto may be 2 to 5 times the inner diameter of the reactor body.

[0016] In the present invention, the spacing between adjacent nozzle groups along the axial direction of the reactor body may be 2 to 5 times the inner diameter of the reactor body.

[0017] In the present invention, the end of the nozzle outlet is flush with the inner wall surface of the reactor body, which can make the radial reaction area in the reactor body as large as possible and make the high temperature area close to the wall surface, which is conducive to wall heat exchange.

[0018] In the present invention, the nozzle is a conventional gas-liquid dual-channel nozzle in the art, and can be a pressure atomizing nozzle or an airflow atomizing nozzle.

[0019] In the present invention, the outlet axis of the nozzle is perpendicular to the axis of the reactor body or inclined downward.

[0020] In the present invention, the reactor body is a conventional tank in the art that can withstand a certain pressure and a certain temperature. The pressure range is generally not greater than 2 MPaG, and the temperature range is generally not greater than 300°C.

[0021] In the present invention, the reactor body may also be provided with a chlorine source inlet, a discharge port and a circulating gas outlet, wherein the chlorine source inlet is located at the upper part of the reactor body, and the discharge port and the circulating gas outlet are both located at the lower part of the reactor body.

[0022] The number of the chlorine source inlets preferably corresponds to the number of the nozzle groups, and one chlorine source inlet is correspondingly arranged above each nozzle group.

[0023] In the present invention, the material reaction process in the reactor is as follows: phosphorus trichloride liquid is divided into multiple streams, which are respectively added to the reactor body through the nozzles, and chemically react with Cl2 in the circulating gas to generate phosphorus pentachloride particles.

[0024] The present invention also provides a phosphorus pentachloride continuous synthesis system, which includes the above-mentioned reactor and a first blower;

[0025] The reactor body is provided with a chlorine source inlet, a material outlet, a circulating gas outlet and a circulating gas inlet;

[0026] The first fan is connected between the circulating air outlet and the circulating air inlet.

[0027] In the present invention, the nozzle may be a pressure atomizing nozzle or an air flow atomizing nozzle, preferably an air flow atomizing nozzle.

[0028] Wherein, when the nozzle is an airflow atomizing nozzle, the gas channel of the nozzle is preferably connected to the circulating gas outlet, and the circulating gas is used as the atomizing gas.

[0029] A second fan and a second cooling device are preferably connected between the gas channel of the nozzle and the circulating gas outlet. The second fan and the second cooling device are arranged in sequence along the flow direction of the circulating gas. The second fan is used to compress the circulating gas into high-pressure gas, and the second cooling device is used to cool the circulating gas.

[0030] The second cooling device may be a conventional heat exchanger in the art.

[0031] The temperature of the heat exchange medium of the second cooling device can be room temperature, and is used to cool the circulating gas to room temperature.

[0032] Wherein, when the nozzle is a pressure atomizing nozzle, a first feed pump is connected to the liquid inlet of the nozzle, and the phosphorus trichloride liquid is pressurized by the first feed pump to achieve pressurized atomization of phosphorus trichloride in the nozzle.

[0033] In the present invention, the chlorine source inlet is preferably located in the area where the nozzles are arranged. More preferably, the number of the chlorine source inlets corresponds to the number of the nozzle groups, and the chlorine source inlet is correspondingly arranged above each nozzle group.

[0034] In the present invention, the chlorine source inlet is preferably connected to a chlorine source pipeline, and the end of the chlorine source pipeline extends deep into the inner center of the reactor body. The end of the chlorine source pipeline is preferably connected to a chlorine source nozzle. By arranging the chlorine source pipeline and the chlorine source nozzle, the chlorine source is sprayed more evenly inside the reactor body.

[0035] In the present invention, the chlorine source is preferably liquid chlorine. Compared with traditional chlorine gas, liquid chlorine absorbs heat and evaporates to produce chlorine gas after entering the reactor, which can provide chlorine gas and cool the reactor at the same time.

[0036] In the present invention, the circulating gas inlet is preferably close to the nozzle, and more preferably, a circulating gas inlet is provided on the reactor body near each nozzle group, so that the cooled circulating gas can more effectively cool the reaction zone near the nozzle.

[0037] In the present invention, the circulating gas outlet is preferably arranged at the lower side of the reactor body.

[0038] In the present invention, the discharge port is preferably arranged at the bottom of the reactor body.

[0039] In the present invention, the wall surface of the reactor body is preferably configured as a water-cooled wall for heat transfer.

[0040] In the present invention, the phosphorus pentachloride continuous synthesis system may further include a first cooling device, which is connected between the first fan and the circulating gas inlet, and is used to cool the circulating gas.

[0041] The first cooling device preferably includes a primary cooling device and a secondary cooling device connected in sequence along the flow direction of the circulating gas, the temperature of the heat exchange medium of the primary cooling device is room temperature, and the temperature of the heat exchange medium of the secondary cooling device is 10-30° C. By setting up two-stage cooling, the circulating gas with a lower temperature enters the reactor to cool the inside of the reactor.

[0042] The primary cooling device and the secondary cooling device may both be conventional heat exchangers in the art.

[0043] In the present invention, the phosphorus pentachloride continuous synthesis system may further include a gas separation and purification device, which is disposed between the circulating gas outlet and the first blower and is used to purify the circulating gas.

[0044] Wherein, the gas separation and purification device comprises a cyclone dust collector and a bag dust collector which are connected in sequence along the flow direction of the circulating gas, the cyclone dust collector is connected to the circulating gas outlet, and the bag dust collector is connected to the first fan.

[0045] When a second fan and a second cooling device are provided, the second fan and the second cooling device are arranged sequentially along the flow direction of the circulating gas, the bag dust collector is also connected to the second fan, the second fan is used to compress the circulating gas into high-pressure gas, and the second cooling device is used to cool the circulating gas.

[0046] In the present invention, the phosphorus pentachloride continuous synthesis system may further include a material discharge flow-aiding device, which is arranged at the material discharge port, and is provided with a fluidizing gas inlet, which is connected to the circulating gas outlet. The circulating gas is used to fluidize the phosphorus pentachloride particles to improve the intermittent or continuous stable discharge of the particles.

[0047] Preferably, when a second fan and a second cooling device are provided, the second fan and the second cooling device are sequentially arranged along the flow direction of the circulating gas, the second fan is connected to the circulating gas outlet, the second fan is used to compress the circulating gas into high-pressure gas, the second cooling device is used to cool the circulating gas, the fluidizing gas inlet is connected to the outlet of the second cooling device, and the cooled circulating gas can also enter the fluidizing gas inlet as fluidizing gas.

[0048] Therein, the fluidizing gas inlets are preferably an even number, and the multiple fluidizing gas inlets are symmetrically arranged.

[0049] Wherein, the material discharge flow-aiding device is preferably a fluidizer.

[0050] Wherein, the circulating gas outlet is preferably located on the side of the reactor body above the material discharge flow-aiding device.

[0051] In the present invention, the phosphorus pentachloride continuous synthesis system may further include a product tank, and the product tank preferably includes a first product tank and a second product tank, wherein the first product tank is connected to the discharge port, and the second product tank is connected to the outlet of the first product tank. By providing the first product tank, the pressure of the gas flow coming out of the reactor body is calibrated, thereby reducing the influence of the circulating gas on the product collection.

[0052] Wherein, when the material discharge port is also provided with the aforementioned material discharge flow-aiding device, the first product tank is connected to the outlet of the material discharge flow-aiding device.

[0053] Preferably, a filter is also provided on the first product tank, the discharge port of the filter is connected to the first product tank, and the air outlet of the filter is connected between the circulating air outlet and the circulating air inlet, so as to remove dust from the material in the first product tank.

[0054] When the aforementioned gas separation and purification device is also provided, the gas outlet of the filter is connected to the inlet of the gas separation and purification device.

[0055] Wherein, the bottom of the first product tank is preferably also provided with the aforementioned material discharge flow-aiding device, and the fluidizing gas inlet of the material discharge flow-aiding device is connected with the circulating gas outlet to perform fluidization treatment on the material in the first product tank.

[0056] Preferably, a second fan and a second cooling device are connected between the fluidizing gas inlet and the circulating gas outlet, and the second fan and the second cooling device are arranged in sequence along the flow direction of the circulating gas. The second fan is connected to the circulating gas outlet, and the second fan is used to compress the circulating gas into high-pressure gas. The fluidizing gas inlet is connected to the outlet of the second cooling device for cooling the circulating gas.

[0057] In the present invention, the phosphorus pentachloride continuous synthesis system may further include a phosphorus trichloride storage tank and a chlorine source storage tank, wherein the phosphorus trichloride storage tank is connected to the liquid channel of the nozzle, and the chlorine source storage tank is connected to the chlorine source inlet.

[0058] In the present invention, the circulating gas is formed as is conventional in the art, generally by introducing chlorine and carbon dioxide into the reactor body to form a mixed gas, and forming a closed circulation loop under the first blower, while liquid chlorine is introduced into the circulating gas after vaporization to generate chlorine.

[0059] The present invention also provides a method for continuously synthesizing phosphorus pentachloride, which adopts the phosphorus pentachloride continuous synthesis system described above for synthesis, and comprises the following steps: passing phosphorus trichloride liquid into the reactor body through the nozzle, the circulating gas is a mixed gas of chlorine and carbon dioxide, and passing a chlorine source into the reactor body through the chlorine source inlet for reaction.

[0060] In the present invention, the volume concentration of the chlorine gas in the circulating gas is preferably 10-30%, for example 20%.

[0061] In the present invention, when the nozzle is an airflow atomizing nozzle, the speed of the circulating gas at the outlet of the nozzle is preferably 20 to 100 m / s, for example, 60 m / s. The speed of the phosphorus trichloride liquid at the outlet of the nozzle is preferably 0.2 to 2 m / s, for example, 1 m / s. More preferably, the speed of the circulating gas at the outlet of the nozzle gradually increases from top to bottom along the axial direction of the reactor body. For example, when a nozzle group is provided, the speed of the circulating gas at the outlet of the nozzle at the top of the reactor body is 60 m / s, and the speed of the circulating gas at the outlet of each nozzle in the nozzle group is 70 m / s.

[0062] When the nozzle is a pressure atomizing nozzle, the pressure drop of the nozzle is preferably 0.1-0.5 MPaG. The velocity of the phosphorus trichloride liquid at the outlet of the nozzle is preferably 2-10 m / s, for example 4 m / s.

[0063] More preferably, the pressure drop of the nozzle gradually increases from top to bottom along the axial direction of the reactor body. For example, when three nozzle groups are provided, the pressure drop of the nozzle at the top of the reactor body is 0.1 MPaG, the pressure drop of each nozzle in the first nozzle group is 0.3 MPaG, the pressure drop of each nozzle in the second nozzle group is 0.4 MPaG, and the pressure drop of each nozzle in the third nozzle group is 0.5 MPaG.

[0064] In the present invention, the flow rate of the circulating gas is determined according to the actual reaction scale. The greater the load, the greater the circulating gas volume. Under a certain load, the greater the circulating gas flow rate, the better the cooling effect. However, when the circulating gas volume is too large, the residence time is short and the reaction conversion rate is low. The circulating gas flow rate is preferably 9000-18000Nm 3 / h.

[0065] In the present invention, the mass flow rate of the phosphorus trichloride is preferably 1.37 to 54.8 tons / h.

[0066] In the present invention, the flow rate of the chlorine source is determined according to the flow rate of phosphorus trichloride, wherein the molar ratio K of chlorine to phosphorus trichloride is preferably 1.0 to 1.05.

[0067] In the present invention, the reaction temperature is preferably 20-60°C, more preferably 30-40°C.

[0068] In the present invention, preferably, the atomized particle size of the phosphorus trichloride decreases from top to bottom along the reactor body.

[0069] The atomized particle size distribution of the phosphorus trichloride can be a two-level distribution, a three-level distribution or a four-level distribution;

[0070] In the two-stage distribution, the primary atomized particle size is preferably 0.1-0.5 mm, the secondary atomized particle size is preferably 0.1-0.15 mm, and the primary atomized particle size is more preferably 0.1-0.2 mm;

[0071] In the three-level distribution, the first-level atomized particle size is preferably 0.2-1 mm, more preferably 0.2-0.4 mm, the second-level atomized particle size is preferably 0.1-0.5 mm, more preferably 0.1-0.2 mm, and the third-level atomized particle size is preferably 0.1-0.15 mm.

[0072] In the four-level distribution, the first-level atomization particle size is preferably 0.3-2mm, more preferably 0.4-0.6mm, the second-level atomization particle size is preferably 0.2-1mm, more preferably 0.2-0.4mm, the third-level atomization particle size is preferably 0.1-0.5mm, more preferably 0.1-0.2mm, and the fourth-level atomization particle size is preferably 0.1-0.15mm.

[0073] The atomized particle size distribution of the phosphorus trichloride is preferably the four-level distribution, so that the large-size phosphorus trichloride particles are located at the top and gradually react during the falling process, and the small-size phosphorus trichloride particles are located at the bottom, which can prolong the entire reaction process and increase the reaction load.

[0074] The atomized particle size distribution of the phosphorus trichloride may also be more than four levels of distribution. When more than four levels of distribution are used, the atomized particle size of phosphorus trichloride after the fourth level is generally 0.1 to 0.15 mm. However, from the perspective of atomization cost, a four-level distribution is preferred.

[0075] The positive and progressive effects of the present invention are:

[0076] (1) The present invention improves the uniformity of material distribution in the space of the reactor body by disposing a plurality of nozzles in layers on the reactor body, thereby improving the heat exchange effect between the material and the heat exchange medium (such as the cooled circulating gas), and reducing or eliminating the high temperature area in the reactor body. In some embodiments of the present invention, the temperature in the reactor can be controlled within the range of 50 to 70°C.

[0077] (2) The continuous synthesis system of the present invention uses the cooled circulating gas to further cool the materials in the reactor to reduce the local high temperature in the reactor; further, liquid chlorine is used as the chlorine source. Compared with traditional chlorine gas, liquid chlorine absorbs heat and evaporates to produce chlorine gas after entering the reactor, which can provide chlorine gas and cool the reactor at the same time.

[0078] (3) The phosphorus pentachloride particles synthesized by the continuous synthesis system of the present invention have large diameter and high purity. BRIEF DESCRIPTION OF THE DRAWINGS

[0079] Figure 1 Schematic diagram of the structure of the phosphorus pentachloride continuous synthesis system of Example 1.

[0080] Figure 2 Schematic diagram of the structure of the phosphorus pentachloride continuous synthesis system of Example 2.

[0081] Figure 3 Schematic diagram of the nozzle structure.

[0082] Description of Reference Numerals

[0083] Reactor 1

[0084] Reactor body 101

[0085] Nozzle 102

[0086] Chlorine source inlet 103

[0087] Discharge port 104

[0088] Recycle gas outlet 105

[0089] Circulating gas inlet 106

[0090] Gas separation and purification device 2

[0091] Cyclone dust collector 201

[0092] Bag dust collector 202

[0093] First fan 3

[0094] The first cooling device 4

[0095] Primary cooling device 401

[0096] Secondary cooling device 402

[0097] Second fan 5

[0098] Second cooling device 6

[0099] Material discharge flow aid device 7

[0100] Fluidizing gas inlet 701

[0101] Phosphorus trichloride storage tank 8

[0102] Chlorine source storage tank 9

[0103] First product tank 10

[0104] Second product tank 11

[0105] Filter 12

[0106] First feed pump 13

[0107] Second feed pump 14 DETAILED DESCRIPTION

[0108] The present invention is further described below by way of examples, but the present invention is not limited to the scope of the examples.

[0109] Example 1

[0110] This embodiment discloses a continuous synthesis system of phosphorus pentachloride. Figure 1 As shown, it includes a reactor 1, a gas separation and purification device 2, a first fan 3, a first cooling device 4, a second fan 5, a second cooling device 6, a material discharge flow aid 7, a phosphorus trichloride storage tank 8, a chlorine source storage tank 9, a first product tank 10, a second product tank 11, a filter 12, a first feed pump 13 and a second feed pump 14.

[0111] The reactor 1 includes a reactor body 101, a nozzle 102 arranged on the top of the reactor body 101, and a nozzle group arranged on the side of the reactor body 101, wherein the nozzle group consists of two nozzles 102 symmetrically arranged around the axis of the reactor body 101, and the spacing between the top nozzle 102 and the nozzle group along the axis direction of the reactor body 101 is 3 times the inner diameter of the reactor body 101, and the nozzle is an airflow atomizing nozzle.

[0112] The reactor body 101 is provided with a chlorine source inlet 103, a discharge port 104, a circulating gas outlet 105 and a circulating gas inlet 106, wherein the chlorine source inlet 103 is arranged above the nozzle group, the chlorine source inlet 103 is connected to a chlorine source pipeline, the end of the chlorine source pipeline extends deep into the inner center of the reactor body 101, and the end of the chlorine source pipeline is connected to a chlorine source nozzle. The discharge port 104 is located at the bottom of the reactor body 101, the circulating gas outlet 105 is located at the lower side of the reactor body 101, and the circulating gas inlet 106 is arranged on the reactor body 101 near the nozzle group. The wall surface of the reactor body 101 adopts a water-cooled wall for heat exchange.

[0113] The gas separation and purification device 2 includes a cyclone dust collector 201 and a bag dust collector 202 connected in sequence along the circulating gas flow direction, the circulating gas outlet 105 is connected to the cyclone dust collector 201, and the first fan 3 and the second fan 5 are connected in parallel to the bag dust collector 202.

[0114] The first cooling device 4 includes a primary cooling device 401 and a secondary cooling device 402 connected in sequence along the flow direction of the circulating gas. The heat exchange medium temperature of the primary cooling device 401 is normal temperature water, and the heat exchange medium of the secondary cooling device 402 is an ice-water mixture with a temperature of about 10°C, which is used to cool the circulating gas to normal temperature. The primary cooling device 401 is connected to the outlet of the first fan 3, which is a circulating fan, and the outlet of the secondary cooling device 402 is connected to the inlet of the circulating gas.

[0115] The inlet of the second cooling device 6 is connected to the outlet of the second fan 5, and the outlet of the second cooling device 6 is connected to the gas passages of all the nozzles 102. The second fan 5 is a high-pressure fan for compressing the circulating gas into atomizing gas.

[0116] The primary cooling device 401, the secondary cooling device 402 and the second cooling device 6 are all heat exchangers.

[0117] The material discharge flow aid device 7 is arranged at the discharge port 104 to fluidize the phosphorus pentachloride particles. The material discharge flow aid device 7 is a fluidizer. Two fluidizing gas inlets 701 are symmetrically arranged at the bottom of the material discharge flow aid device 7. The two fluidizing gas inlets 701 are connected in parallel to the outlet of the second cooling device 6. The circulating gas outlet 105 is located on the side of the reactor body 101 above the material discharge flow aid device 7.

[0118] The phosphorus trichloride storage tank 8 is connected to the liquid channels of all nozzles 102, the first feed pump 13 is arranged between the phosphorus trichloride storage tank 8 and the nozzles 102, the chlorine source storage tank 9 is connected to the chlorine source inlet 103, the chlorine source is liquid chlorine, and the second feed pump 14 is arranged between the chlorine source storage tank 9 and the chlorine source inlet 103.

[0119] The first product tank 10 is connected to the outlet of the material discharge flow aid device 7, and the second product tank 11 is connected to the outlet of the first product tank 10. The high-pressure gas flow coming out of the reactor body 101 is pressure-calibrated through the first product tank 10.

[0120] A material discharge flow aid 7 is also provided at the bottom of the first product tank 10 , the second product tank 11 is connected to the bottom of the material discharge flow aid 7 , and the two fluidizing gas inlets at the bottom of the material discharge flow aid 7 are also connected in parallel to the outlet of the second cooling device 6 .

[0121] The filter 12 is disposed on the first product tank 10 , the discharge port of the filter 12 is connected to the first product tank 10 , and the air outlet of the filter 12 is connected to the outlet of the bag filter 202 for dust removal of the material in the first product tank 10 .

[0122] In this embodiment, a mixture of carbon dioxide and chlorine is first introduced into the reactor body 101, and circulating gas is formed under the action of the first fan 3. The chlorine source and phosphorus trichloride liquid enter the reactor body 101, and the phosphorus trichloride liquid particles react with the chlorine to generate phosphorus pentachloride. The circulating gas flows out from the circulating gas outlet 105, and is divided into two paths after passing through the gas separation and purification device 2. One path is cooled by the first fan 3 and the first cooling device 4, and then enters the reactor body 101 through the circulating gas inlet 106 to cool the interior of the reactor body 101. The other path is compressed into high-pressure gas by the second fan 5, and after cooling by the second cooling device 6, enters the nozzle 102 and the material discharge flow aid 7, and circulates according to the above process.

[0123] The production scale of phosphorus pentachloride in the continuous synthesis system of this embodiment is 500 tons per day.

[0124] The above continuous synthesis system is used to synthesize phosphorus pentachloride, and the synthesis method includes:

[0125] Using the circulating gas as the atomizing gas of the nozzle, the phosphorus trichloride liquid is introduced into the reactor body 101 through the nozzle 102, and the liquid chlorine is introduced into the reactor body 101 through the chlorine source inlet 103 to carry out the reaction;

[0126] The nozzle is an air flow atomizing nozzle, such as Figure 3 As shown in the figure, the contraction angle a of the nozzle channel is 60°, and the airflow nozzle structure is as described in the literature "Cao Xiankui, Xu Jianliang. Initial atomization process of coaxial double-channel airflow atomizing nozzle [J]. Journal of Chemical Industry, 2006, 57(11): 2592". Figure 1 The structure recorded.

[0127] In the top nozzle, the circulating gas velocity at the nozzle outlet is 60m / s, and the phosphorus trichloride liquid velocity at the nozzle outlet is 1m / s. In the two side nozzles, the circulating gas velocity at the nozzle outlet is 70m / s, and the phosphorus trichloride liquid velocity at the nozzle outlet is 1m / s.

[0128] The mass flow rate of phosphorus trichloride is 13.7 tons / h, the mass flow rate of liquid chlorine is 7.21 tons / h, the molar ratio of Cl2 to PCl3 is K=1.02, the circulating gas is a mixture of chlorine and carbon dioxide, the volume concentration of chlorine in the circulating gas is 20%, and the flow rate of the circulating gas is 9000Nm 3 / h, the internal pressure of the reactor body was 20 kPaG, and the reaction temperature was set at 40°C.

[0129] The particle size of phosphorus trichloride was measured by a laser particle size analyzer. The particle size of phosphorus trichloride in this embodiment was distributed in two levels: the primary atomized particle size was 0.1-0.2 mm, and the secondary atomized particle size was 0.1-0.15 mm.

[0130] The maximum temperature in the furnace of this embodiment is 50° C., the average particle size SMD of phosphorus pentachloride is 50 um, and the purity of phosphorus pentachloride is 99.99%.

[0131] Comparative Example 1

[0132] This comparative example adopts the synthesis system described in Example 1 of patent CN116920764A for synthesis, the number of nozzles is 1, the circulating gas is the same as that in Example 1, and the flow rate of the circulating gas is 18000Nm 3 / h, the reactor pressure is 0.1MPa, the phosphorus trichloride flow rate is 13.7 tons / h, and the reactor pressure is 0.1MPaG.

[0133] The nozzle of this comparative example is the same as that of Example 1, the velocity of the circulating gas at the nozzle outlet is 70 m / s, and the velocity of the phosphorus trichloride liquid at the nozzle outlet is 1 m / s.

[0134] The production scale, reactor inner diameter and synthesis setting temperature are the same as those in Example 1.

[0135] The particle size of the phosphorus trichloride in this comparative example is 0.1 to 0.15 mm.

[0136] The maximum temperature in the furnace of this comparative example is 90° C., the average particle size SMD of phosphorus pentachloride is 15 μm, and the purity of phosphorus pentachloride is 99.80%.

[0137] Example 2

[0138] The structure of the phosphorus pentachloride continuous synthesis system in this embodiment is as follows Figure 2 As shown, it is basically the same as the phosphorus pentachloride continuous synthesis system of Example 1, except that:

[0139] The number of nozzles 102 in this embodiment is 7. Figure 1 As shown, one of the nozzles 102 is arranged at the top of the reactor body 101, and the remaining six nozzles 102 are grouped in pairs to form three nozzle groups. The three nozzle groups are arranged in sequence from top to bottom along the axial direction of the reactor body 101, and the two nozzles of each nozzle group are symmetrically arranged with the axis of the reactor body 101 as the center. The projections of all the nozzles 102 in the three nozzle groups on the cross section of the reactor body 101 are distributed at equal intervals along the circumference of the reactor body 101; a liquid chlorine inlet 103 is arranged above each nozzle group.

[0140] The outlet of the second cooling device 6 is not connected to the nozzle 102 , and pressure atomization of the nozzle 102 is formed by the pressure and flow control of the first feed pump 13 .

[0141] The diameter of the reactor body is 1.2 times that of Example 1, and the height-to-diameter ratio of the reactor body is the same as that of Example 1.

[0142] The nozzle 102 is a pressure atomizing nozzle, and the pressure nozzle structure is the nozzle structure described in Example 1 in CN1164442A.

[0143] From the top of the reactor body downward, the pressure drop of the top nozzle is 0.1 MPaG, the pressure drop of each nozzle in the first nozzle group is 0.3 MPaG, the pressure drop of each nozzle in the second nozzle group is 0.4 MPaG, and the pressure drop of each nozzle in the third nozzle group is 0.5 MPaG. The phosphorus trichloride flow rate at the outlet of each nozzle is the same, which is 4 m / s.

[0144] The production scale is 1000 tons per day, the internal pressure of the reactor body 101 is 20kpa, and the circulating gas volume is 18000Nm 3 / h, and the phosphorus trichloride flow rate is 27.4 tons / h.

[0145] The remaining structures, steps and parameters are the same as those in Example 1.

[0146] The particle size of phosphorus trichloride was measured by a laser particle size analyzer. The physicochemical particle size of phosphorus trichloride in the reactor was distributed in four levels: the first-level atomization particle size was 0.4-0.6 mm, the second-level atomization particle size was 0.2-0.4 mm, the third-level atomization particle size was 0.1-0.2 mm, and the fourth-level atomization particle size was 0.1-0.15 mm.

[0147] The maximum temperature in the furnace of this embodiment is 60° C., the average particle size SMD of phosphorus pentachloride is 40 um, and the purity of phosphorus pentachloride is 99.99%.

[0148] Comparative Example 2

[0149] This comparative example adopts the synthesis system described in Example 1 of patent CN116920764A for synthesis, the number of nozzles is 1, the circulating gas is the same as that in Example 1, and the flow rate of the circulating gas is 36000Nm 3 / h, the inner diameter of the reactor is twice that of Example 2, the reactor pressure is 0.1 MPaG, and the phosphorus trichloride flow rate is 27.4 tons / h.

[0150] The nozzle of this comparative example is the same as that of Example 2, the pressure drop of the nozzle is 0.5 MPaG, and the velocity of the phosphorus trichloride liquid at the nozzle outlet is 4 m / s.

[0151] The production scale, reactor inner diameter and synthesis setting temperature are the same as those in Example 2.

[0152] The particle size of phosphorus trichloride was measured by a laser particle size analyzer, and the atomized particle size was 0.1 to 0.15 mm.

[0153] The maximum temperature in the furnace of this comparative example is 120° C., the average particle size SMD of phosphorus pentachloride is 10 um, and the purity of phosphorus pentachloride is 99.80%.

[0154] Example 3

[0155] The difference between this embodiment and the first embodiment is that the nozzle 102 of this embodiment is a pressure atomizing nozzle, and the structure of the pressure nozzle is the same as that of the second embodiment.

[0156] The outlet of the second cooling device 6 is not connected to the nozzle 102 , and pressure atomization of the nozzle 102 is formed by the pressure and flow control of the first feed pump 13 .

[0157] From the top of the reactor body downward, the pressure drop of the top nozzle is 0.4 MPaG, and the pressure drop of the two nozzles in the nozzle group is 0.5 MPaG. The phosphorus trichloride flow rate at the outlet of each nozzle is equal, both 4 m / s.

[0158] The remaining structures, steps and parameters are the same as those in Example 1.

[0159] The atomized particle size of phosphorus trichloride in this embodiment is the same as that in embodiment 1.

[0160] The maximum temperature in the furnace of this embodiment is 50° C., the average particle size SMD of phosphorus pentachloride is 50 um, and the purity of phosphorus pentachloride is 99.99%.

[0161] Example 4

[0162] The difference between this embodiment and embodiment 2 is that the nozzle 102 of this embodiment is an airflow atomizing nozzle, and the structure of the airflow atomizing nozzle is the same as that of embodiment 1. The outlet of the second cooling device 6 is connected to the gas channels of all the nozzles 102 .

[0163] From the top of the reactor body downward, in the top nozzle, the speed of the circulating gas at the nozzle outlet is 40m / s; in the first nozzle group, the speed of the circulating gas at the outlet of each nozzle is 50m / s; in the second nozzle group, the speed of the circulating gas at the outlet of each nozzle is 60m / s; in the third nozzle group, the speed of the circulating gas at the outlet of each nozzle is 70m / s; the speed of the phosphorus trichloride liquid at the nozzle outlet is 1m / s.

[0164] The remaining structures, steps and parameters are the same as those in Example 2.

[0165] The particle size of phosphorus trichloride was measured by a laser particle size analyzer. The physicochemical particle size of phosphorus trichloride in the reactor was distributed in four levels: the first-level atomization particle size was 0.4-0.6 mm, the second-level atomization particle size was 0.2-0.4 mm, the third-level atomization particle size was 0.1-0.2 mm, and the fourth-level atomization particle size was 0.1-0.15 mm.

[0166] The maximum temperature in the furnace of this embodiment is 60° C., the average particle size SMD of phosphorus pentachloride is 40 um, and the purity of phosphorus pentachloride is 99.99%.

[0167] Comparative Example 3

[0168] The difference between this comparative example and Example 1 is that the nozzle spacing of this comparative example is 1.5 times the inner diameter of the reactor body, and the remaining structures, steps and parameters are the same as those of Example 1.

[0169] The particle size of phosphorus trichloride was measured by a laser particle size analyzer. The particle size of phosphorus trichloride was distributed in two levels: the first-level atomization particle size was 0.1-0.2 mm, and the second-level atomization particle size was 0.1-0.15 mm.

[0170] The maximum temperature in the furnace of this embodiment is 80° C., the diameter of phosphorus pentachloride is 20 um, and the purity of phosphorus pentachloride is 99.99%.

[0171] Comparative Example 4

[0172] The difference between this comparative example and Example 1 is that the nozzle spacing of this comparative example is 6 times the inner diameter of the reactor body, and the remaining structures, steps and parameters are the same as those of Example 1.

[0173] The particle size of phosphorus trichloride was measured by a laser particle size analyzer. The particle size of phosphorus trichloride was distributed in two levels: the first-level atomization particle size was 0.1-0.2 mm, and the second-level atomization particle size was 0.1-0.15 mm.

[0174] The maximum temperature in the furnace of this embodiment is 40° C., the diameter of phosphorus pentachloride is 50 μm, and the purity of phosphorus pentachloride is 99.99%, but the investment is increased by 3 times.

Claims

1. A phosphorus pentachloride synthesis reactor, characterized in that: It comprises a reactor body, a nozzle arranged at the top of the reactor body and at least one nozzle group arranged horizontally around the side of the reactor body, each of the nozzle groups comprises at least two nozzles; the distance between the top of the reactor body and the nozzle groups adjacent thereto is 2 to 5 times the inner diameter of the reactor body; When the number of the nozzle groups is greater than or equal to 2, the multiple nozzle groups are arranged in sequence from top to bottom along the axis of the reactor; the spacing between adjacent nozzle groups along the axial direction of the reactor body is 2 to 5 times the inner diameter of the reactor body.

2. The phosphorus pentachloride synthesis reactor according to claim 1, characterized in that: The number of nozzles in each nozzle group is an even number, and the nozzles in each nozzle group are symmetrically arranged with the axis of the reactor body as the center; the total number of the nozzles is, for example, 3, 5 or 7; and / or, projections of the nozzles in two adjacent nozzle groups on the cross section of the reactor body are distributed at equal intervals along the circumference of the reactor body, and the cross section of the reactor body refers to a surface perpendicular to the axis of the reactor body; and / or, the end of the outlet of the nozzle is flush with the inner wall surface of the reactor body; And / or, the nozzle is a pressure atomizing nozzle or an air flow atomizing nozzle; And / or, the axis of the outlet of the nozzle is perpendicular to the axis of the reactor body or inclined downward; And / or, the reactor body is further provided with a chlorine source inlet, a discharge port, a circulating gas outlet and a circulating gas inlet, the chlorine source inlet is located at the upper part of the reactor body, and the discharge port and the circulating gas outlet are both located at the lower part of the reactor body; the number of the chlorine source inlets preferably corresponds to the number of the nozzle groups, and a chlorine source inlet is correspondingly provided above each of the nozzle groups.

3. The phosphorus pentachloride synthesis reactor according to claim 2, characterized in that: There are three nozzles in total, one of which is arranged at the top of the reactor body, and the other two nozzles are arranged horizontally around the side of the reactor body and symmetrically around the axis of the reactor body; Or, there are 7 nozzles, one of which is arranged at the top of the reactor body, and the remaining six nozzles are grouped in pairs to form three nozzle groups, and the three nozzle groups are arranged in sequence from top to bottom along the axial direction of the reactor body, and the two nozzles in each nozzle group are horizontally arranged around the side of the reactor body symmetrically with the axis of the reactor body as the center, and the projections of the nozzles in the three nozzle groups on the cross section of the reactor body are evenly distributed along the circumference of the reactor body.

4. A phosphorus pentachloride continuous synthesis system, characterized in that: It comprises the phosphorus pentachloride synthesis reactor according to any one of claims 1 to 3 and a first blower; The reactor body is provided with a chlorine source inlet, a material outlet, a circulating gas outlet and a circulating gas inlet; The first fan is connected between the circulating air outlet and the circulating air inlet.

5. The phosphorus pentachloride continuous synthesis system according to claim 4, characterized in that: When the nozzle is an airflow atomizing nozzle, the gas channel of the nozzle is connected to the circulating gas outlet; Preferably, a second fan and a second cooling device are connected between the gas passage of the nozzle and the circulating gas outlet, and the second fan and the second cooling device are sequentially arranged along the flow direction of the circulating gas, the second fan is used to compress the circulating gas into high-pressure gas, and the second cooling device is used to cool the circulating gas; The second cooling device is preferably a heat exchanger; When the nozzle is a pressure atomizing nozzle, a first feed pump is connected to the liquid inlet of the nozzle, and the phosphorus trichloride liquid is pressurized by the first feed pump.

6. The phosphorus pentachloride continuous synthesis system according to claim 4, characterized in that: The chlorine source inlet is connected to a chlorine source pipeline, and the end of the chlorine source pipeline extends deep into the inner center of the reactor body; preferably, the end of the chlorine source pipeline is connected to a chlorine source nozzle; And / or, the chlorine source is liquid chlorine; and / or, a circulating gas inlet is disposed on the reactor body near each of the nozzle groups; And / or, the circulating gas outlet is arranged at the lower side of the reactor body; And / or, the discharge port is arranged at the bottom of the reactor body; And / or, the wall surface of the reactor body is configured as a water-cooled wall.

7. The phosphorus pentachloride continuous synthesis system according to claim 4, characterized in that: The phosphorus pentachloride continuous synthesis system further comprises a first cooling device, the first cooling device is connected between the first fan and the circulating gas inlet, and the first cooling device is used to cool the circulating gas; The first cooling device preferably comprises a primary cooling device and a secondary cooling device connected in sequence along the flow direction of the circulating gas, the temperature of the heat exchange medium of the primary cooling device is room temperature, and the temperature of the heat exchange medium of the secondary cooling device is 10-30°C; the primary cooling device and the secondary cooling device are preferably both heat exchangers; And / or, the phosphorus pentachloride continuous synthesis system further comprises a gas separation and purification device, which is arranged between the circulating gas outlet and the first blower and is used to purify the circulating gas; Preferably, the gas separation and purification device comprises a cyclone dust collector and a bag dust collector connected in sequence along the flow direction of the circulating gas, the cyclone dust collector is connected to the circulating gas outlet, and the bag dust collector is connected to the first fan; Preferably, when a second fan and a second cooling device are provided, the second fan and the second cooling device are sequentially arranged along the flow direction of the circulating gas, the second fan is connected to the bag filter, the second fan is used to compress the circulating gas into high-pressure gas, and the second cooling device is used to cool the circulating gas; And / or, the phosphorus pentachloride continuous synthesis system further comprises a material discharge flow-aiding device, the material discharge flow-aiding device is arranged at the material discharge port, a fluidizing gas inlet is arranged on the material discharge flow-aiding device, and the fluidizing gas inlet is connected to the circulating gas outlet; Preferably, when the phosphorus pentachloride continuous synthesis system further includes a second fan and a second cooling device, the second fan and the second cooling device are sequentially arranged along the flow direction of the circulating gas, the second fan is connected to the circulating gas outlet, the second fan is used to compress the circulating gas into high-pressure gas, the second cooling device is used to cool the circulating gas, and the fluidizing gas inlet is connected to the outlet of the second cooling device, so that the cooled circulating gas enters the fluidizing gas inlet; The fluidizing gas inlets are preferably an even number, and the plurality of fluidizing gas inlets are symmetrically arranged; The material discharge flow-aiding device is preferably a fluidizer; The circulating gas outlet is preferably located at the side of the reactor body above the material discharge flow aid device.

8. The phosphorus pentachloride continuous synthesis system according to claim 4, characterized in that: The phosphorus pentachloride continuous synthesis system further includes a product tank, the product tank includes a first product tank and a second product tank, the first product tank is connected to the discharge port, and the second product tank is connected to the outlet of the first product tank; Preferably, when the material discharge port is further provided with a material discharge flow-aiding device, the first product tank is connected to the outlet of the material discharge flow-aiding device, and the material discharge flow-aiding device is further provided with a fluidizing gas inlet, and the fluidizing gas inlet is connected to the circulating gas outlet; Preferably, a filter is further provided on the first product tank, the discharge port of the filter is connected to the first product tank, and the gas outlet of the filter is connected between the circulating gas outlet and the circulating gas inlet; Preferably, a material discharge flow-aiding device is further provided at the bottom of the first product tank, and a fluidizing gas inlet is provided on the material discharge flow-aiding device, and the fluidizing gas inlet is connected to the circulating gas outlet; And / or, the phosphorus pentachloride continuous synthesis system further comprises a phosphorus trichloride storage tank and a chlorine source storage tank, the phosphorus trichloride storage tank is connected to the liquid channel of the nozzle, and the chlorine source storage tank is connected to the chlorine source inlet.

9. A method for continuous synthesis of phosphorus pentachloride, characterized in that: The phosphorus pentachloride continuous synthesis system according to any one of claims 4 to 8 is used for synthesis, and the method comprises the following steps: introducing phosphorus trichloride liquid into the reactor body through the nozzle, the circulating gas is a mixed gas of chlorine and carbon dioxide, and introducing a chlorine source into the reactor body through the chlorine source inlet for reaction.

10. The method for continuous synthesis of phosphorus pentachloride according to claim 9, characterized in that: When the nozzle is an air flow atomizing nozzle, the speed of the circulating gas at the outlet of the nozzle is 20-100 m / s, for example, 60 m / s, and the speed of the phosphorus trichloride liquid at the outlet of the nozzle is 0.2-2 m / s, for example, 1 m / s; preferably, the speed of the circulating gas at the outlet of the nozzle gradually increases from top to bottom along the axial direction of the reactor body, for example, when one nozzle group is provided, the speed of the circulating gas at the outlet of the nozzle at the top of the reactor body is 60 m / s, and the speed of the circulating gas at the outlet of each nozzle in the nozzle group is 70 m / s; When the nozzle is a pressure atomizing nozzle, the pressure drop of the nozzle is 0.1-0.5 MPaG, and the speed of the phosphorus trichloride liquid at the outlet of the nozzle is 2-10 m / s, for example, 4 m / s; preferably, the pressure drop of the nozzle gradually increases from top to bottom along the axial direction of the reactor body. For example, when three nozzle groups are provided, the pressure drop of the nozzle at the top of the reactor body is 0.1 MPaG, the pressure drop of each nozzle in the first nozzle group is 0.3 MPaG, the pressure drop of each nozzle in the second nozzle group is 0.4 MPaG, and the pressure drop of each nozzle in the third nozzle group is 0.5 MPaG; And / or, the flow rate of the circulating gas is 9000~18000Nm 3 / h; And / or, the mass flow rate of the phosphorus trichloride is 1.37 to 54.8 tons / h; and / or, the molar ratio K of the chlorine gas to the phosphorus trichloride is 1.0 to 1.05; And / or, the reaction temperature is 20-60°C, preferably 30-40°C; And / or, the atomized particle size of the phosphorus trichloride decreases from top to bottom along the reactor body, for example, the atomized particle size distribution of the phosphorus trichloride may be a two-stage distribution, a three-stage distribution or a four-stage distribution; In the two-stage distribution, the primary atomization particle size is preferably 0.1 to 0.5 mm, more preferably 0.1 to 0.2 mm, and the secondary atomization particle size is preferably 0.1 to 0.15 mm; In the three-level distribution, the first-level atomization particle size is preferably 0.2-1 mm, more preferably 0.2-0.4 mm, the second-level atomization particle size is preferably 0.1-0.5 mm, more preferably 0.1-0.2 mm, and the third-level atomization particle size is preferably 0.1-0.15 mm; In the four-level distribution, the first-level atomization particle size is preferably 0.3-2mm, more preferably 0.4-0.6mm, the second-level atomization particle size is preferably 0.2-1mm, more preferably 0.2-0.4mm, the third-level atomization particle size is preferably 0.1-0.5mm, more preferably 0.1-0.2mm, and the fourth-level atomization particle size is preferably 0.1-0.15mm.

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