Production apparatus for phenylchlorosilane, production apparatus control method, and production method

Abstract

The application provides a production device, a production device control method and a preparation method of a phenyl chlorosilane. The production device comprises a reactor, a catalyst circulation device and a catalyst. The reactor is used for accommodating a reaction raw material and is provided with an outlet and an inlet. The catalyst circulation device is in communication with the outlet and the inlet respectively and is used for driving at least part of the catalyst to circulate in and out of the reactor. The reaction raw material comprises a chlorosilane and a benzene compound, and the catalyst comprises boron trifluoride or boron trichloride. The application can realize the recycling of the catalyst in the production process of the phenyl chlorosilane, separate the catalyst from hydrogen generated in the reaction, improve the reaction efficiency of the catalyst, and thus reduce the production cost of the phenyl chlorosilane.

Description

Technical Field

[0001] This invention relates to the technical field of chemical processes, specifically to a production equipment containing phenylchlorosilane, a production equipment control method, and a preparation method. Background Technology

[0002] Phenylchlorosilanes are special organosilicon monomers used to manufacture special organosilicon polymers that meet specific properties such as high temperature resistance, radiation resistance, and high light transmittance. Diphenyldichlorosilane is also a key raw material for manufacturing catalysts for olefin-directed polymerization.

[0003] Currently, there are two main methods for producing phenylchlorosilanes in China: the high-temperature gas-phase condensation method and the direct method. Phenylchlorosilanes mainly include methylphenyldichlorosilane, phenyltrichlorosilane, diphenyldichlorosilane, methylchlorophenyldichlorosilane, ethylphenyldichlorosilane, and so on.

[0004] Boron trifluoride and boron trichloride can be used as catalysts in the production of phenylchlorosilanes. Although boron trifluoride and boron trichloride catalysis can effectively reduce the reaction temperature, their low boiling points and the generation of difficult-to-condense hydrogen gas make the catalyst easily carried away, severely reducing the catalytic reaction efficiency and affecting the use of this process in the production of phenylchlorosilanes.

[0005] Therefore, in the production process of phenylchlorosilanes, how to prevent the boron trifluoride and boron trichloride catalysts from being carried away by hydrogen, which is difficult to condense, has become one of the technical problems that urgently need to be solved by those skilled in the art. Summary of the Invention

[0006] The technical problem to be solved by this invention is: how to prevent the boron trifluoride and boron trichloride catalysts from being carried away by hydrogen, which is difficult to condense, in the production process of phenylchlorosilane.

[0007] To address the above problems, the present invention provides a production apparatus for preparing phenylchlorosilanes. The production apparatus includes: a reactor for containing reaction raw materials and having an outlet and an inlet; and a catalyst circulation device connected to the outlet and inlet, respectively, for driving at least a portion of the catalyst to circulate in and out of the reactor. The reaction raw materials include chlorosilanes and benzene compounds, and the catalyst includes boron trifluoride or boron trichloride.

[0008] In any of the above technical solutions, the production equipment further includes: a porous gas distribution pipe, which is located inside the reactor and at the bottom of the reactor. The porous gas distribution pipe is used to drive the catalyst flow by bubbling. The outlet is located at the top of the reactor, the inlet is located on the side wall of the reactor, and at least part of the catalyst circulation device extends to the porous gas distribution pipe via the inlet.

[0009] In any of the above technical solutions, the production equipment further includes: an auger, which is located in the reactor and is used to promote the swirling mixing of the reaction raw materials by rotation.

[0010] In any of the above technical solutions, the reactor includes: a feeding valve located at the top of the reactor and used to feed the reactants into the reactor; and / or a discharge valve located at the bottom of the reactor and used to discharge the reaction products obtained from the reaction of the reactants from the reactor.

[0011] In any of the above technical solutions, the catalyst circulation device includes: a benzene removal and condensation device, which is located at the top of the reactor and connected to the reactor; a first cooling device, which is located at the top of the benzene removal and condensation device and connected to the benzene removal and condensation device; and a three-way pipe fitting, which includes a first pipe, a second pipe, and a third pipe; wherein the first pipe is connected to the top of the first cooling device and is used to collect the catalyst from the reactor; the second pipe is connected to the first pipe and is used to add the catalyst; and the third pipe is connected to the first pipe and is used to send the catalyst into the reactor and separate the catalyst from the hydrogen produced by the reaction.

[0012] In any of the above technical solutions, the first pipeline gradually slopes upward from the end closest to the first cooling device to the end furthest from the first cooling device; the second pipeline is opened vertically upward; the third pipeline is opened vertically downward; a first shut-off valve is provided between the first cooling device and the first pipeline; a cryogenic condensation device is connected to the top of the second pipeline, the top of the cryogenic condensation device is connected to the second cooling device, a pressure relief valve and a high-pressure gas cylinder for supplying catalyst are respectively connected to the top of the second cooling device, a second shut-off valve is provided between the pressure relief valve and the second cooling device, a third shut-off valve is provided between the high-pressure gas cylinder and the second cooling device; a fourth shut-off valve is provided between the third pipeline and the reactor; a metering tube is sleeved on the third pipeline; a third cooling device is sleeved on the third pipeline; the third pipeline is a U-shaped pipe for forming a liquid level difference.

[0013] To address the above problems, this invention provides a control method for production equipment used to prepare phenylchlorosilanes. The control method controls the production equipment as described in any of the above technical solutions. The control method includes: controlling the opening of the reactor's feed valve to feed the reaction raw materials into the reactor; controlling the opening of the third shut-off valve and controlling the closing of the first shut-off valve, the second shut-off valve, the fourth shut-off valve, and the cryogenic condensation device, so that a high-pressure gas cylinder charges a gaseous catalyst into a closed three-way pipe, and the catalyst is liquefied in a limited quantity in a metering tube to meter the catalyst; and sequentially controlling the opening of the cryogenic condensation device, the first shut-off valve, the fourth shut-off valve, and the second shut-off valve, and controlling the reactor temperature to the reaction temperature.

[0014] In any of the above technical solutions, the control method further includes: collecting the hydrogen emission from the pressure relief valve and controlling the reaction temperature and / or reaction time of the reactor based on the hydrogen emission; and / or opening the porous gas distribution pipe in the reactor so that the porous gas distribution pipe drives the catalyst flow through bubbling.

[0015] To address the above problems, the present invention provides a method for preparing phenylchlorosilanes. The preparation method uses the production equipment described in any of the above technical solutions. The preparation method includes: feeding the reaction raw materials into a reactor and supplying a catalyst into the reactor; wherein the reaction pressure in the reactor is 10 MPa, the reaction temperature is 200 °C, the reaction time is 8 h, and the amount of catalyst added is 1% to 5% of the reaction raw materials.

[0016] To address the above problems, the present invention provides a phenylchlorosilane, which is obtained by the method described in any of the above technical solutions.

[0017] The production equipment of this invention includes a reactor and a catalyst circulation device. The reactor is used to contain the reaction raw materials and has an outlet and an inlet. The catalyst circulation device is connected to the outlet and inlet respectively and is used to drive at least a portion of the catalyst to circulate in and out of the reactor. This allows for the recycling of the catalyst. The reaction raw materials include chlorosilanes and benzene compounds, and the catalyst includes boron trifluoride or boron trichloride. In the production process of phenylchlorosilanes, the boron trifluoride and boron trichloride catalysts are carried away by hydrogen gas, which is difficult to condense. Therefore, this invention connects the outlet and inlet of the reactor to the catalyst circulation device, which continuously separates the catalyst discharged from the reactor from the hydrogen gas and returns the catalyst to the reactor. Thus, this invention enables the recycling of the catalyst in the production process of phenylchlorosilanes, improves the reaction efficiency of the catalyst, and thereby reduces the production cost of phenylchlorosilanes. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of a production equipment for preparing phenylchlorosilanes according to an embodiment of the present invention;

[0019] Figure 2 This is a schematic diagram of the preparation process of phenylchlorosilanes according to an embodiment of the present invention.

[0020] Explanation of reference numerals in the attached figures

[0021] Reactor-100; Outlet-100a; Inlet-100b; Catalyst circulation device-200; Porous gas distribution pipe-300; Feed valve-101; Discharge valve-102; Benzene removal and condensation device-201; First cooling device-202; T-fitting-203; First pipeline-203a; Second pipeline-203b; Third pipeline-203c; First shut-off valve-204; Cryogenic condensation device-205; Second cooling device-206; Pressure relief valve-207; High-pressure gas cylinder-208; Second shut-off valve-209; Third shut-off valve-210; Fourth shut-off valve-211; Metering pipe-212; Third cooling device-213. Detailed Implementation

[0022] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described in detail below with reference to specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0023] Numerous specific details are set forth in the following description to provide a thorough understanding of the invention. However, the invention may be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below. Without conflict, the following technical features of the embodiments of the invention can be combined with each other.

[0024] like Figure 1 As shown, an embodiment of the present invention provides a production apparatus for preparing phenylchlorosilanes. The production apparatus includes: a reactor 100 for containing reaction raw materials and having an outlet 100a and an inlet 100b; and a catalyst circulation device 200 connected to the outlet 100a and the inlet 100b, respectively, for driving at least a portion of the catalyst to circulate in and out of the reactor 100; wherein the reaction raw materials include chlorosilanes and benzene compounds, and the catalyst includes boron trifluoride or boron trichloride.

[0025] In the above embodiments, the reactor 100 is a high-pressure reactor for small-scale testing, a heat-heated coil reactor for batch preparation of phenylchlorosilanes, or a tubular reactor for continuous preparation of phenylchlorosilanes.

[0026] Optionally, a heater is fitted into the wall of the reactor 100 to control the temperature within the reactor 100. Exemplarily, the heater is one of the following: a cast iron heater, a cast aluminum heater, or a cast copper heater.

[0027] In one example, taking a high-pressure reactor used for pilot testing as reactor 100, the dimensions of reactor 100 are φ89mm × 5mm × 600mm. Reactor 100 is made of 347 stainless steel. Reactor 100 is a vertical cylindrical shape.

[0028] The reaction in reactor 100 produces, for example, phenylchlorosilanes such as methylphenyldichlorosilane, phenyltrichlorosilane, diphenyldichlorosilane, methylchlorophenyldichlorosilane, and ethylphenyldichlorosilane.

[0029] For example, the chlorosilane in the reaction raw materials is methyldichlorosilane, the benzene compound is benzene, and the ratio of the amount of methyldichlorosilane to benzene added is 143:97.

[0030] In one example, the feed amount of the reaction material in reactor 100 is 1200g, including 715g of monomethylhydrodichlorosilane and 485g of benzene. The reaction pressure in reactor 100 is 10MPa, the reaction temperature is 200℃, the reaction time is 8h, the amount of catalyst added is 1% to 5% of the reaction material, and the reaction product obtained in reactor 100 is methylphenyldichlorosilane with a yield of 38%.

[0031] Preferably, the catalyst is boron trifluoride, and the amount of catalyst added is 1% of the reactants.

[0032] In the above embodiments, the catalyst circulation device 200 is used to drive the catalyst to circulate between the outlet 100a and the inlet 100b of the reactor 100, and to separate the catalyst from the hydrogen produced by the reaction, so as to improve the utilization efficiency of the catalyst and avoid unnecessary loss of the catalyst.

[0033] like Figure 1 As shown, in some embodiments of the present invention, the production equipment further includes a porous gas distribution pipe 300, which is disposed within the reactor 100 and located at the bottom of the reactor 100. The porous gas distribution pipe 300 is used to drive the catalyst flow by bubbling. An outlet 100a is located at the top of the reactor 100, and an inlet 100b is located on the side wall of the reactor 100. At least a portion of the catalyst circulation device 200 extends to the porous gas distribution pipe 300 via the inlet 100b.

[0034] Since inlet 100b is located on the side wall of reactor 100, the tail end of the U-shaped tube of catalyst circulation device 200 can enter reactor 100 through the side wall of reactor 100 and extend downwards towards the porous gas distribution pipe 300 located at the bottom of reactor 100. Therefore, the porous gas distribution pipe 300 can better bubble the catalyst from catalyst circulation device 200, driving uniform and effective catalyst circulation.

[0035] like Figure 1 As shown, in some embodiments of the present invention, the reactor 100 includes a feeding valve 101, which is located at the top of the reactor 100 and is used to feed reaction raw materials into the reactor 100.

[0036] like Figure 1 As shown, in some embodiments of the present invention, the reactor 100 includes a discharge valve 102, which is disposed at the bottom of the reactor 100 and is used to discharge the reaction product obtained by the reaction of the raw materials from the reactor 100.

[0037] In some embodiments of the present invention, the production equipment further includes an auger (not shown in the figure), which is disposed in the reactor 100 and is used to cause the reaction raw materials to swirl and mix by rotation.

[0038] It is understood that the production equipment in the embodiments of the present invention can be used for pilot testing, or it can be used for actual production using the intermittent method or the continuous method after fine-tuning some of the equipment or devices.

[0039] In actual continuous production, reactor 100 is a tubular reactor made of a 347 stainless steel circular straight tube with dimensions of φ108×8×10000. An auger is installed inside reactor 100.

[0040] The following is an example of the fabrication process for the auger in reactor 100 used in continuous production. The built-in 304 stainless steel auger in reactor 100 has dimensions of 90×38×90×3 mm and is fixed by welding through a central φ38×2 347 stainless steel pipe. The auger arrangement causes swirling mixing of the reactants as they flow within the pipe. During auger fabrication, φ108×8×10000 pipes can be laid flat and compactly stacked within a horizontally placed square frame 3200 mm wide, 12 m long, and 1400 mm high. Using a baffle heat exchanger fabrication method, alternating horizontal and vertical grids are employed to firmly restrict the movement of the pipe cross-section in all directions, thereby suppressing vibration damage caused by gas-liquid mixing. The grids utilize square fixing rods with dimensions of 30×30 or 32×32 mm. The pipes are tightly stacked and fixed in layers, with 22 φ108×8×10000 pipes in each layer. Nine layers are arranged within the frame, totaling 198 pipes, with a pipe spacing of 140mm. Starting from the bottom layer, adjacent pipe ends at the same horizontal height are sequentially welded together at both ends using custom-made Ω-shaped large bend joints (the use of this type of bend is a key structure for achieving a compact pipe arrangement. This large bend joint can be supplied as two separate bends, making the bend easier to manufacture. Although it adds three welds during installation, two of these welds can be done by welding robots, and the remaining weld needs to be done manually, but the working conditions are better, thus increasing efficiency and reliability). Then, it is welded together with the layer above, finally forming a 2265-meter-long folded pipeline within the frame.

[0041] It should be noted that for continuous production, a spiral auger needs to be installed in the straight section of the reaction tube. The gap between the auger and the inner wall of the high-pressure pipe should be less than 2mm to meet the requirements of preventing auger vibration and reducing gas-liquid short-circuit flow.

[0042] It is understandable that, in the actual manufacturing of continuous production equipment, for convenience, the elbows at both ends of the weld are first assembled into a whole by welding the pipes layer by layer using positioning molds, and then hoisted and stacked in the frame for layer-by-layer welding and fixing. By stacking 10 such pipe-laying frames and welding the pipes of adjacent upper and lower frames together, a reactor with a single pipeline up to 22,650 meters long can be formed. The equipment is 16 meters high and occupies an area of ​​12,000 × 4,000 square meters. The internal volume of its high-pressure reaction tube is 150 cubic meters. Based on the reaction effect of the pilot plant, when using boron trifluoride as a catalyst, the inlet liquid velocity of this reactor 100 can be set to 0.33 m / s, with a single-pass conversion rate of over 35%. Calculated based on an annual reaction time of 8,600 hours and an operating pressure of 10 MPa, considering the high-temperature liquid density and gas phase volume, the production capacity of methylphenyl dichlorosilane can be 18,000 tons / year. The cost of this reactor 100 is around 40 million yuan, which is still economically viable. Because this reaction process is a weakly endothermic reaction with a heat output of 8–25 kJ / mol to 25 kJ / mol, hot air at atmospheric pressure can be circulated outside the reaction tube to control the reaction temperature. Since leaked material is prone to spontaneous combustion, nitrogen is preferred for the circulating hot air to ensure safety. A low-pressure-drop, split-type heat pipe heat exchanger transfers heat from the furnace to the circulating hot nitrogen. Online chromatographic monitoring of the circulating nitrogen purity allows for timely detection of any abnormalities and facilitates emergency response.

[0043] In some embodiments of the present invention, the catalyst circulation device 200 includes: a benzene removal and condensation device 201, which is located at the top of the reactor 100 and communicates with the reactor 100; a first cooling device 202, which is located at the top of the benzene removal and condensation device 201 and communicates with the benzene removal and condensation device 201; and a three-way pipe fitting 203, which includes a first pipe 203a, a second pipe 203b, and a third pipe 203c; wherein the first pipe 203a communicates with the top of the first cooling device 202 and is used to collect the catalyst from the reactor 100; the second pipe 203b communicates with the first pipe 203a and is used to add the catalyst; and the third pipe 203c communicates with the first pipe 203a and is used to feed the catalyst into the reactor 100 and separate the catalyst from the hydrogen produced by the reaction.

[0044] It is understood that the production equipment in this embodiment of the invention can be used for pilot testing, or, after minor adjustments to some equipment or devices, for actual batch production or continuous production. The condensation device can be a condensation column for pilot testing, or a bubble-cap distillation column for batch preparation of phenylchlorosilanes. The cooling device can be a cooling jacket for pilot testing, or a vertical tube condenser for batch preparation of phenylchlorosilanes.

[0045] In the case of small-scale testing, the benzene removal condensation device 201 is specifically a cooling jacket with dimensions of φ10mm×2mm×1500mm. The benzene removal condensation device 201 is a vertical cylinder. The reactor 100 and the benzene removal condensation device 201 have a direct and smooth transition to prevent flooding. The first cooling device 202 has a cooling temperature of -5℃ and is used to remove benzene with a high melting point, providing condensate reflux. The cooling temperature of the first cooling device 202 is controlled by a cryogenic coolant circulation pump DLSB-5 / 10. The length of the first cooling device 202 is 200mm.

[0046] The tee fitting 203 is formed by welding three inner tubes with a size of φ10×2 through a 90-degree tee with a size of φ14×2. This tee is used to prevent the feed from the cryogenic condensation device 205 from entering the upwardly inclined first pipe 203a.

[0047] In some embodiments of the present invention, the first pipe 203a gradually slopes upward from the end near the first cooling device 202 to the end away from the first cooling device 202; the second pipe 203b is vertically upward; the third pipe 203c is vertically downward; a first shut-off valve 204 is provided between the first cooling device 202 and the first pipe 203a; a cryogenic condensation device 205 is connected to the top of the second pipe 203b, and a second cooling device 206 is connected to the top of the cryogenic condensation device 205. The top of the device is connected to a pressure relief valve 207 and a high-pressure gas cylinder 208 for supplying catalyst. A second shut-off valve 209 is provided between the pressure relief valve 207 and the second cooling device 206. A third shut-off valve 210 is provided between the high-pressure gas cylinder 208 and the second cooling device 206. A fourth shut-off valve 211 is provided between the third pipeline 203c and the reactor 100. A metering tube 212 is sleeved on the third pipeline 203c. A third cooling device 213 is sleeved on the third pipeline 203c. The third pipeline 203c is a U-shaped pipe for forming a liquid level difference.

[0048] The first shut-off valve 204 is a high-pressure resistant shut-off valve. The catalyst vaporized in the reactor 100 enters the slightly upward-sloping, -20°C first pipe 203a (i.e., the jacketed cooling zone) through the open first shut-off valve 204. The first pipe 203a is a φ10×2 inclined upward horizontal pipe, which does not obstruct the upward flow of hydrogen.

[0049] A metering tube 212, with an internal volume of 45 ml, is installed at the position of the three-way fitting 203. This metering tube is used to measure the amount of catalyst, such as boron trifluoride, added. For example, in each small-scale experiment, 50 g of boron trifluoride is actually charged, but only 10 g to 12 g can remain in the reactor 100 to form a catalytic effect. The inner tube consists of two specifications: φ10×2 and φ6×1.5×2000 pipes. The φ10×2 pipe is the metering tube 212, and the φ6×1.5×2000 pipe is the third pipe 203c. The third pipe 203c is a U-shaped delivery pipe with assisted cooling, and its temperature is controlled by a low-temperature cooling liquid circulation pump DLSB-10 / 30. The third pipe 203c is used to return the condensed catalyst, such as boron trifluoride, to the reactor 100 via a differential flow. After entering the middle of the reactor 100, the catalyst bends downwards to the bottom and enters a horizontally placed porous gas distribution pipe 300, where it flows out in bubbles. The reflux liquid leaves the cooling pipe (i.e., the third pipe 203c) and passes through the fourth shut-off valve 211 before entering the reactor 100. A cryogenic condensation device 205 is connected to the top of the second pipe 203b. The cryogenic condensation device 205 has dimensions of φ10×2×1200 and is used to prevent substances with boiling points higher than the catalyst from reaching the second cooling device 206. The second cooling device 206 is a cryogenic jacket (-100℃) (ethanol coolant melting point -114℃). The cryogenic jacket (temperature controlled by a low-temperature coolant circulation pump DLSB-5 / 120) reduces catalyst loss due to hydrogen outflow.

[0050] This invention also provides a method for controlling production equipment for preparing phenylchlorosilanes. This method controls the production equipment of any of the above-described technical solutions, and includes:

[0051] S101. Control the opening of the feed valve of the reactor to feed the reaction raw materials into the reactor;

[0052] S102. Control the third shut-off valve to open, and control the first shut-off valve, second shut-off valve, fourth shut-off valve and cryogenic condensation device to close, so that the high-pressure gas cylinder can charge the gaseous catalyst into the closed three-way pipe fitting, and the catalyst can be liquefied in a limited amount in the metering tube to meter the catalyst.

[0053] S103, sequentially control the opening of the cryogenic condensation device, the first shut-off valve, the fourth shut-off valve and the second shut-off valve, and control the reactor temperature to rise to the reaction temperature.

[0054] Specifically, regarding S101, the feeding of the reaction raw materials is completed before the catalyst feeding. After the feeding is completed, the feeding valve can be closed. Subsequently, via S102, the third shut-off valve is opened, and the first, second, and fourth shut-off valves and the cryogenic condensation device are closed. Thus, the first, second, and fourth shut-off valves, when closed, form a closed catalyst receiving chamber. The third shut-off valve is opened, allowing high-pressure gas charging via a 12 MPa high-pressure gas cylinder. The catalyst is metered using the limited liquefaction effect of the -20°C third cooling device 213 (e.g., a cooling jacket). During the receiving process, the cryogenic condensation device (e.g., the cryogenic jacket) is not activated.

[0055] Regarding S103, the activation sequence of each component or device in this step is sequential. Specifically, after the catalyst is fed, the cryogenic condensation unit, which performs cryogenic cooling, needs to be started first. Once it is operating normally, the first shut-off valve is opened to allow the catalyst to enter the reactor. The catalyst entering the reactor causes a pressure increase, and non-condensable gases are driven to the cryogenic condensation unit. Then, the fourth shut-off valve is opened to allow the catalyst to circulate, continuously bubbling the material in the reactor. After observing that the pressure increase is slow, the second shut-off valve is opened. The above operating steps ensure that the cryogenic condensation unit ensures that the catalyst is fully liquefied in the closed space, achieving precise metering. This allows the catalyst to enter the reactor, where it undergoes vaporization and circulation. The pressure increase in the reactor caused by the catalyst drives the non-condensable gases to the cryogenic condensation unit and discharges them. Therefore, this control method not only achieves precise catalyst metering but also ensures the effective discharge of non-condensable gases.

[0056] It should be noted that the second shut-off valve has a very small opening and provides damping. This second shut-off valve is a high-pressure back-pressure valve, equipped with a high-pressure buffer tank. A shut-off valve is installed at the outlet of the back-pressure valve to prevent overshoot and drastic pressure fluctuations caused by a large pressure difference when the back-pressure valve operates. After completing the above operations, the reactor temperature is controlled to rise to the reaction temperature.

[0057] In some embodiments of the present invention, the control method further includes: opening the porous gas distribution pipe in the reactor so that the porous gas distribution pipe is bubbled through to drive the catalyst flow.

[0058] In some embodiments of the present invention, the control method further includes: collecting the hydrogen emission from the pressure relief valve, and controlling the reaction temperature and / or reaction time of the reactor based on the hydrogen emission.

[0059] In other words, the hydrogen produced in the reaction can be discharged into a gas collection device. This device can be a 600-liter atmospheric pressure plastic gas holder. The hydrogen discharged into the collection device is measured, and the change in gas volume over time is recorded to estimate the reaction rate.

[0060] The gas collection device is set in a lime water tank. The exhaust gas is bubbled in the lime water to remove active toxic substances such as boron fluoride before entering the gas holder for metering.

[0061] This invention also provides a method for preparing phenylchlorosilanes, which uses production equipment as described in any of the above technical solutions, and includes the following steps:

[0062] The reactants are added to the reactor, and a catalyst is supplied to the reactor.

[0063] The reaction pressure in reactor 100 is 10 MPa, the reaction temperature is 200℃, the reaction time is 8 h, and the amount of catalyst added is 1% to 5% of the raw materials.

[0064] For example, in the production of diphenyldichlorosilane, the embodiments of the present invention first use a copper or nickel-containing powder catalyst formulation in a fluidized bed reactor at 1.5 MPa to 3.5 MPa and 250°C to 400°C. Trichlorosilane, hydrogen chloride, and hydrogen are mixed in a molar ratio of 1:1 to 3:4 to 6 and then reacted with silicon powder with a purity of 98% or higher to obtain a mixed hydrochlorosilane with a dichlorodichlorosilane content of 10 to 80% (this process is the same as the silicon tetrachloride hydrochlorination process used in polycrystalline silicon production, and is used to replace the trichlorosilane disproportionation method to reduce the production cost of dichlorodichlorosilane). Then, this mixture is reacted with benzene in a high-pressure pipeline at 180 to 270°C in a molar ratio of 1:1 to 2.5 to obtain a higher yield of diphenyldichlorosilane, while phenyltrichlorosilane and triphenylmonochlorosilane are produced as byproducts.

[0065] For example, embodiments of the present invention can use a 1:1 molar ratio of monomethylhydrodichlorosilane and benzene to react in a high-pressure pipeline at 120–280°C to produce methylphenyldichlorosilane, and 1–10% of trimethylchlorosilane can be added to the reactants as an inhibitor to suppress the formation of phenyltrichlorosilane.

[0066] For example, embodiments of the present invention can use monomethylhydrodichlorosilane and chlorobenzene in a molar ratio of 1:1 to react in a high-pressure pipeline at 120-280°C to produce methylchlorophenyldichlorosilane.

[0067] like Figure 2As shown, the process flow of the continuous reactor system is as follows: Fresh benzene, recovered benzene and hydrochlorosilane, fresh inhibitor and recovered inhibitor are mixed. The mixture is pressurized to above 12MPa by a high-lift pump, heated to 150°C with steam, and then mixed with low-temperature mixture from the catalyst recovery system to prevent benzene from freezing and causing blockage. The mixture is then heated to the reaction temperature with heat transfer oil as needed, and then enters the reactor tube. The reactor tube is heated by circulating hot air to maintain the reaction temperature. The reactor tube feed first reaches the high-pressure pre-separation tower, where the rectification section removes benzene from the rising gas to prevent the cryogenic system from freezing and clogging. The stripping section removes the catalyst from the downstream liquid by heating the bottom of the tower with a small amount of heat. The bottom liquid then goes to the low-pressure rectification section to separate and recover unreacted feedstock. The rising gas from the high-pressure pre-separation tower rectification section is sequentially cooled by water and then pre-cooled to obtain reflux liquid. This reflux liquid is then sequentially cooled by heat exchange with low-temperature tail gas, cryogenically cooled to -80°C, washed with low-temperature fresh hydrochlorosilane, and treated by a demister. This process condenses and separates unreacted feedstock and catalyst from the hydrogen, allowing them to be recovered. The resulting low-temperature recovered mixture is pressurized by a high-lift pump and first used as the primary pre-cooling source for the high-pressure pre-separation tower before being mixed with the preheated benzene-containing mixture and sent to the reactor. The fresh hydrochlorosilane pre-cooled mixture is then cryogenically cooled to -80°C and used as the washing liquid for the high-pressure hydrogen, absorbing and removing gaseous catalyst from the hydrogen. The purified hydrogen is discharged under the control of a back-pressure high-pressure stabilizing valve for further processing and utilization of the tail gas. Similar to the intermittent method, the continuous method also requires a similar system to ensure safety by washing and treating the gases emitted from the reactor system in the event of a power outage.

[0068] For the reactor in the batch production unit, the system flow is similar to that of the pilot-scale test. The difference lies in replacing the fractional condenser column with a bubble cap distillation column, replacing the cooling jacket with a dedicated vertical tube condenser, and replacing the scaled-up high-pressure reactor with a safer heat transfer medium heating coil. A power outage emergency venting gas treatment system is also added. This system is equipped with its own generator and performs two-stage washing of the venting gas. The first stage uses anhydrous ethanol to decompose chlorosilanes and the catalyst, releasing hydrogen chloride and hydrogen fluoride. The second stage uses lime water to remove hydrogen chloride and hydrogen fluoride. The washed gas component is hydrogen, which is safely discharged at a high altitude through pipeline, meeting the safety requirements for capacity scaling up. When discharging from the bottom of the reactor, the valve is closed to cut off the catalyst circulation. The reactor is maintained at a high temperature without cooling, and a high-pressure resistant discharge buffer tank is used to ensure that the liquid is not emptied during each discharge, preventing the gaseous catalyst from being released. For restarting, the reactants are added to the high-temperature reactor via a high-lift metering pump.

[0069] In summary, the embodiments of this invention use low-boiling-point boron trifluoride or boron trichloride as catalysts, and maintain a rotating and mixed flow with the reaction raw materials in a high-pressure pipeline. The reaction is carried out continuously at temperatures below 300°C to produce phenylchlorosilanes. This avoids high-temperature cracking, coking, and blockage of the raw materials, prevents equipment from being subjected to high-temperature chlorine corrosion and severe wear, and offers high raw material utilization. The catalyst can be continuously recovered and recycled, no highly toxic byproducts are produced, the product is easy to purify, and the byproducts are easily rendered harmless. The equipment can be compactly arranged, has high energy utilization, and requires little space when scaling up production, thus reducing the production cost of large-scale plants. Furthermore, the embodiments of this invention design a pilot-scale device suitable for the preparation of phenylchlorosilanes using boron trifluoride and boron trichloride catalysis. This device implements a gas catalyst circulation bubbling process, improving catalytic efficiency. The design principles of pilot-scale trials can be used to design batch production devices for the production of phenylchlorosilanes using boron trifluoride or boron trichloride catalysis, meeting the cost reduction requirements for small-batch production.

[0070] In this invention, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance; the term "multiple" refers to two or more unless otherwise explicitly defined. The terms "install," "connect," "link," and "fix" should be interpreted broadly. For example, "connect" can be a fixed connection, a detachable connection, or an integral connection; "link" can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0071] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A production apparatus for preparing phenylchlorosilanes, characterized in that, The production equipment includes: The reactor (100) is used to contain the reaction raw materials and is provided with an outlet (100a) and an inlet (100b). A catalyst circulation device (200) is connected to the outlet (100a) and the inlet (100b) respectively, and is used to drive at least a portion of the catalyst to circulate in and out of the reactor (100). The reaction raw materials include chlorosilanes and benzene compounds, and the catalyst includes boron trifluoride or boron trichloride; The catalyst recycling unit (200) includes: A benzene removal and condensation device (201) is provided at the top of the reactor (100) and is connected to the reactor (100); The first cooling device (202) is located on top of the benzene removal and condensation device (201) and is connected to the benzene removal and condensation device (201); T-fitting (203), the t-fitting (203) includes a first pipe (203a), a second pipe (203b) and a third pipe (203c); The first pipeline (203a) is connected to the top of the first cooling device (202) and is used to collect the catalyst from the reactor (100); the second pipeline (203b) is connected to the first pipeline (203a) and is used to deliver the catalyst; the third pipeline (203c) is connected to the first pipeline (203a) and is used to feed the catalyst into the reactor (100) and separate the catalyst from the hydrogen produced by the reaction. The first pipe (203a) gradually slopes upward from the end closest to the first cooling device (202) toward the end furthest from the first cooling device (202); the second pipe (203b) is opened vertically upward; and the third pipe (203c) is opened vertically downward. A first shut-off valve (204) is provided between the first cooling device (202) and the first pipeline (203a); The top of the second pipeline (203b) is connected to a cryogenic condensation device (205), the top of the cryogenic condensation device (205) is connected to a second cooling device (206), the top of the second cooling device (206) is connected to a pressure relief valve (207) and a high-pressure gas cylinder (208) for supplying the catalyst, a second shut-off valve (209) is provided between the pressure relief valve (207) and the second cooling device (206), and a third shut-off valve (210) is provided between the high-pressure gas cylinder (208) and the second cooling device (206). A fourth shut-off valve (211) is provided between the third pipeline (203c) and the reactor (100); a metering pipe (212) is fitted onto the third pipeline (203c); a third cooling device (213) is fitted onto the third pipeline (203c); the third pipeline (203c) is a U-shaped pipe used to form a liquid level difference.

2. The production equipment according to claim 1, characterized in that, The production equipment also includes: A porous gas distribution pipe (300) is disposed inside the reactor (100) and located at the bottom of the reactor (100). The porous gas distribution pipe (300) is used to drive the catalyst flow by bubbling. The outlet (100a) is located at the top of the reactor (100), the inlet (100b) is located on the side wall of the reactor (100), and at least a portion of the catalyst circulation device (200) extends to the porous gas distribution pipe (300) via the inlet (100b).

3. The production equipment according to claim 1, characterized in that, The production equipment also includes: An auger is disposed in the reactor (100) and is used to cause the reactants to swirl and mix by rotation.

4. The production equipment according to claim 1, characterized in that, The reactor (100) includes: A feed valve (101) is located at the top of the reactor (100) and is used to feed the reaction raw materials into the reactor (100); and / or A discharge valve (102) is provided at the bottom of the reactor (100) and is used to discharge the reaction product obtained by the reaction of the raw materials from the reactor (100).

5. A method for controlling production equipment used to prepare phenylchlorosilanes, characterized in that, The control method is used to control the production equipment as described in any one of claims 1 to 4, the control method comprising: The feed valve of the reactor is controlled to open so as to feed the reaction raw materials into the reactor; the feed valve (101) is located at the top of the reactor (100); The third shut-off valve is opened, and the first shut-off valve, the second shut-off valve, the fourth shut-off valve, and the cryogenic condensation device are closed, so that the high-pressure gas cylinder fills the sealed three-way pipe with gaseous catalyst, and the catalyst is liquefied in a limited amount in the metering tube to measure the catalyst. The cryogenic condensation device, the first shut-off valve, the fourth shut-off valve, and the second shut-off valve are opened sequentially, and the reactor is heated to the reaction temperature.

6. The control method according to claim 5, characterized in that, The control method further includes: The amount of hydrogen emitted from the pressure relief valve is collected, and the reaction temperature and / or reaction time of the reactor are controlled based on the amount of hydrogen emitted.

7. A method for preparing phenylchlorosilanes, characterized in that, The preparation method uses the production equipment as described in any one of claims 1 to 4, and the preparation method includes: The reactants are added to the reactor, and the catalyst is supplied to the reactor. The reactor has a reaction pressure of 10 MPa, a reaction temperature of 200°C, a reaction time of 8 h, and the catalyst is added at a rate of 1% to 5% of the reaction raw materials.

8. A phenylchlorosilane, characterized in that, Obtained by the method described in claim 7.

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