CN110283204B - System and method for preparing methyl phosphite ester by adopting aluminum methyl chloride - Google Patents

System and method for preparing methyl phosphite ester by adopting aluminum methyl chloride Download PDF

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CN110283204B
CN110283204B CN201810226487.3A CN201810226487A CN110283204B CN 110283204 B CN110283204 B CN 110283204B CN 201810226487 A CN201810226487 A CN 201810226487A CN 110283204 B CN110283204 B CN 110283204B
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methyl
gas
bed reactor
fluidized bed
aluminum
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CN110283204A (en
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周曙光
秦龙
李培国
余神銮
祝小红
陈华涛
徐亚卿
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Zhejiang Xinan Chemical Industrial Group Co Ltd
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Zhejiang Xinan Chemical Industrial Group Co Ltd
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    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07FACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAINING ELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN, SULFUR, SELENIUM OR TELLURIUM
    • C07F5/00Compounds containing elements of Groups 3 or 13 of the Periodic Table
    • C07F5/06Aluminium compounds
    • C07F5/061Aluminium compounds with C-aluminium linkage
    • C07F5/064Aluminium compounds with C-aluminium linkage compounds with an Al-Halogen linkage
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07FACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAINING ELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN, SULFUR, SELENIUM OR TELLURIUM
    • C07F9/00Compounds containing elements of Groups 5 or 15 of the Periodic Table
    • C07F9/02Phosphorus compounds
    • C07F9/28Phosphorus compounds with one or more P—C bonds
    • C07F9/48Phosphonous acids [RP(OH)2] including [RHP(=O)(OH)]; Thiophosphonous acids including [RP(SH)2], [RHP(=S)(SH)]; Derivatives thereof
    • C07F9/4808Phosphonous acids [RP(OH)2] including [RHP(=O)(OH)]; Thiophosphonous acids including [RP(SH)2], [RHP(=S)(SH)]; Derivatives thereof the acid moiety containing a substituent or structure which is considered as characteristic
    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07FACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAINING ELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN, SULFUR, SELENIUM OR TELLURIUM
    • C07F9/00Compounds containing elements of Groups 5 or 15 of the Periodic Table
    • C07F9/02Phosphorus compounds
    • C07F9/28Phosphorus compounds with one or more P—C bonds
    • C07F9/50Organo-phosphines
    • C07F9/52Halophosphines

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Abstract

The invention provides a system and a preparation method for preparing methyl phosphite ester by adopting methyl aluminum chloride, wherein the system comprises a methyl aluminum chloride synthesis unit, a methyl phosphorus dichloride synthesis unit and a methyl phosphite ester synthesis unit which are sequentially connected; the methyl aluminium chloride synthesis unit comprises a fluidized bed reactor and a separation unit which are connected in sequence, the methyl phosphorus dichloride synthesis unit comprises a methyl phosphorus dichloride synthesis device, and the methyl phosphorus dichloride synthesis device is a closed reaction kettle. The invention carries out gas-solid catalytic reaction in a fluidized bed reactor and optimizes separation equipment to prepare a methyl aluminum chloride product, and then prepares the methyl phosphorus dichloride by taking the methyl aluminum chloride as a raw material, thereby continuously synthesizing the methyl phosphite ester product. The yield of the methyl phosphorus dichloride is improved, the yield of the methyl phosphite ester product is further improved, the operation is simple and convenient, three wastes are not generated basically, a solvent is not needed, and the method is green and environment-friendly.

Description

System and method for preparing methyl phosphite ester by adopting aluminum methyl chloride
Technical Field
The invention belongs to the field of organic chemical synthesis, relates to a system and a method for preparing methyl phosphite ester, and particularly relates to a system and a method for preparing methyl phosphite ester by preparing and separating methyl aluminum chloride in a fluidized bed reactor and preparing methyl phosphorus dichloride in an improved reactor by using the prepared methyl aluminum chloride.
Background
The methyl phosphite ester is an important chemical raw material intermediate, and can be widely applied to preparation of flame retardants and herbicides. The methyl phosphite ester structure is shown below:
CH3P(OR)n(OH)2-n
wherein, the group R is alkyl with 1-4C atoms, and n is 1 or 2. The substances have wide application and can be used for flame retardant synthesis, pesticide synthesis and the like.
Methyl phosphine dichloride is used as a raw material for efficiently synthesizing methyl phosphite ester, and can relatively easily perform chemical reaction based on weak chemical bonds. Conventionally, the synthesis method of methyl phosphorus dichloride mainly comprises the following steps according to different synthesis raw materials: (1) the synthesis (German Bayer process) takes methane and phosphorus trichloride as raw materials; (2) methyl chloride and red phosphorus processes; (3) phosphorus trichloride and trimethylaluminum; (4) phosphorus trichloride and methyl aluminum chloride processes; (5) ternary (chloromethane, aluminum trichloride and phosphorus trichloride) complex aluminum powder reduction method.
The existing synthesis methods have respective advantages and disadvantages, and US 4101573 discloses a method for synthesizing methyl phosphorus dichloride in one step at 600 ℃ by using carbon tetrachloride as an initiator and methane and phosphorus trichloride as raw materials, wherein the yield is 80-98% when the conversion rate is 10-30%. However, the method requires that the conversion rate of phosphorus trichloride is not more than 35 percent, otherwise, the yield is obviously reduced, the crude product is a mixture of phosphorus trichloride and methyl phosphorus dichloride, the boiling points of the phosphorus trichloride and the methyl phosphorus dichloride are close, the separation is difficult, and the equipment cost of the method is very high due to the material properties and high-temperature reaction conditions.
A simple precipitation of methylphosphonous dichloride (Synthesis, 1977, 1977(07): 450:. 450) reports that methyl dichloride is prepared by ternary complex method using methyl iodide, phosphorus trichloride and aluminum trichloride as raw materials, and the methyl dichloride is obtained by reducing the ternary complex compound at low temperature with iron powder, adding potassium chloride and distilling, wherein the yield of the method is 70-80%, but the cost of methyl iodide is high.
Plum, named et al, proposed a synthesis method of "methyl phosphorus dichloride synthesis" (pesticide, 2011, 50(2):97-99) using 1,1,2, 2-tetrachloroethane as solvent and chloromethane, aluminum trichloride and phosphorus trichloride as raw materials, reacting for 6h at 80 ℃ to obtain a ternary complex, then reducing with aluminum at 140 ℃, distilling while reacting to obtain the product methyl phosphorus dichloride, wherein the total yield is 76.2%. However, the method needs a large amount of solvent consumption, and the phosphorus trichloride which is not completely reacted is mixed in the solvent, so that the recovery cost of the solvent and the raw materials is increased.
Therefore, the existing synthesis methods of methyl phosphorus dichloride have different defects, batch kettle type operation is mostly adopted for synthesizing the intermediate and the methyl phosphorus dichloride in the existing synthesis methods of the methyl phosphorus dichloride, the reaction time is long, the yield is low, the operation environment and the intensity are large, and great potential safety and environmental protection hazards exist, so that the yield of the methyl phosphorus dichloride is reduced, and the yield of subsequent preparation of methyl phosphite ester is further influenced.
Disclosure of Invention
Aiming at the problems that the prior art cannot continuously prepare the methyl phosphite ester, the product yield is low, the side reactions are increased, the product purification cost is high and the like, the invention provides a system and a preparation method for preparing the methyl phosphite ester by adopting aluminum methyl chloride. The invention takes a fluidized bed reactor as a synthesis reactor of methyl aluminum chloride, performs gas-solid catalytic reaction in the fluidized bed reactor, optimizes separation equipment, prepares a methyl aluminum chloride product, and then takes methyl aluminum chloride and phosphorus trichloride to react in an optimized methyl phosphorus dichloride synthesis device to generate a ligand 3CH3PCl2·2AlCl3,3CH3PCl2·2AlCl3Reacting with alkali metal halide such as NaCl to obtain methyl phosphorus dichloride, and further continuously synthesizing methyl phosphite ester products. According to the invention, the yield of the methyl phosphorus dichloride is improved by optimizing the structure and reaction conditions of the reactor, so that the yield of the methyl phosphite ester product is improved, the operation is simple and convenient, three wastes are not generated basically, no solvent is needed, and the method is green and environment-friendly.
In order to achieve the purpose, the invention adopts the following technical scheme:
in a first aspect, the present invention provides a system for preparing methyl phosphite, the system comprising a methyl aluminum chloride synthesis unit, a methyl phosphorus dichloride synthesis unit and a methyl phosphite synthesis unit; the synthesis unit of methyl aluminium chloride comprises a fluidized bed reactor and a separation unit which are connected in sequence, the synthesis unit of methyl phosphorus dichloride comprises a synthesis device of methyl phosphorus dichloride, and the synthesis device of methyl phosphorus dichloride is a closed reaction kettle; and the methyl aluminum chloride obtained by the methyl aluminum chloride synthesis unit enters a methyl phosphorus dichloride synthesis unit, and the methyl phosphorus dichloride obtained by the methyl phosphorus dichloride synthesis unit enters a methyl phosphite synthesis unit.
The invention takes aluminum powder and chloromethane as raw materials to prepare intermediate methyl aluminum chloride for synthesizing methyl phosphorus dichloride, the raw materials and a catalyst carry out gas-solid catalytic reaction in a fluidized bed reactor under the condition of fluidization, and the reaction equation of the reaction is as follows:
3CH3Cl+2Al→CH3AlCl2+(CH3)2AlCl
the reaction raw materials are fluidized in the fluidized bed reactor to react, so that the mass transfer process is increased, the reaction rate is improved, and higher yield can be achieved in a short time; moreover, the fluidized bed reactor can realize continuous operation, and the production efficiency is improved.
And products obtained by the reaction of the fluidized bed reactor are separated by a separation unit, and the yield of the methyl aluminum chloride is further improved by optimizing separation equipment in the separation process.
The prepared methyl aluminum chloride reacts with phosphorus trichloride to generate ligand 3CH3PCl2·2AlCl3,3CH3PCl2·2AlCl3Reacting with alkali metal halide such as NaCl to obtain the methyl phosphorus dichloride, wherein the reaction equation of the reaction is as follows:
CH3AlCl2+(CH3)2AlCl+3PCl3→3CH3PCl2·2AlCl3
3CH3PCl2·2AlCl3+2NaCl→3CH3PCl2+2NaAlCl4
the reaction for synthesizing the methyl phosphorus dichloride is carried out in a closed reaction kettle, which is beneficial to improving the simplicity of the synthesis operation of the methyl phosphorus dichloride.
The obtained methyl phosphorus dichloride is further reacted with alcohol to prepare methyl phosphite ester.
The following technical solutions are preferred technical solutions of the present invention, but not limited to the technical solutions provided by the present invention, and technical objects and advantageous effects of the present invention can be better achieved and achieved by the following technical solutions.
As the preferable technical scheme of the invention, the bottom of the fluidized bed reactor is provided with a gas material inlet, the side wall of the fluidized bed reactor is provided with a solid material inlet, and a reaction raw material catalyst, a raw material aluminum and gasified chloromethane react in the fluidized bed reactor.
Preferably, the gas material inlet is connected with a methyl chloride conveying pipeline.
Preferably, a heating device is arranged on the methyl chloride conveying pipeline.
Preferably, a gas distributor is arranged above a gas material inlet at the bottom in the fluidized bed reactor, and gas material is subjected to gas distribution from the gas material inlet at the bottom of the fluidized bed reactor through the gas distributor.
Preferably, the gas distributor has an open pore content of 0.1% to 15%, for example 0.1%, 0.5%, 1%, 3%, 5%, 7%, 10%, 13%, or 15%, but not limited to the recited values, and other values not recited within this range are equally applicable, preferably 0.2% to 5%.
In the invention, the aperture ratio of the air holes on the gas distributor needs to be controlled within a certain range, and if the aperture ratio is too large, the poor fluidization quality and the blockage of the distribution plate can be caused; if the aperture ratio is too small, the phenomena of temperature runaway and burning are easy to occur, the material leakage and blockage of the distribution plate are easy to cause, and the aperture ratio is low, the resistance of the distribution plate is large, and the energy consumption is large.
Preferably, the apertures of the openings in the gas distributor are 3mm to 8mm, such as 3mm, 4mm, 5mm, 6mm, 7mm or 8mm, but not limited to the values recited, and other values not recited within this range are equally applicable.
Preferably, the holes on the gas distributor are round holes, elliptical holes, triangular holes, square holes or regular polygonal holes.
Preferably, the openings on the gas distributor are distributed in a triangular shape, a circular shape, a square shape or a rhombic shape.
Preferably, a heat exchanger is arranged in the fluidized bed reactor.
Preferably, the heat exchanger is disposed above the gas distributor.
Preferably, the heat exchanger is any one of a U-tube heat exchanger, a finger-tube heat exchanger or a serpentine heat exchanger, or a combination of at least two of them, typical but non-limiting examples being: the combination of a U-shaped tube heat exchanger and a finger-shaped tube heat exchanger, the combination of a finger-shaped tube heat exchanger and a snake-shaped heat exchanger, the combination of a U-shaped tube heat exchanger, a finger-shaped tube heat exchanger and a snake-shaped heat exchanger, and the like.
In the invention, because the catalytic reaction of the chloromethane and the aluminum powder is strong heat release, the heat in the fluidized bed must be removed in time, otherwise, the internal temperature of the fluidized bed is overheated, the actual yield of the target product is influenced, and potential safety hazards exist.
In the invention, the heat exchanger can adopt heat conduction oil as a heat exchange medium.
As the preferable technical scheme of the invention, the separation unit comprises a gas-solid separation device and a gas treatment device which are sequentially connected, a material outlet of the fluidized bed reactor is connected with a material inlet of the gas-solid separation device, a gas outlet of the gas-solid separation device is connected with an inlet of the gas treatment device, and solid materials of the gas-solid separation device return to the fluidized bed reactor.
Preferably, the gas-solid separation device is a cyclone separator.
Preferably, the number of gas-solid separation means is not less than 1, such as 1,2 or 3 and the like and above, but is not limited to the recited values, and other values not recited within this range are equally applicable.
Preferably, the gas-solid separation device is placed above the inside of the fluidized bed reactor and/or outside the fluidized bed reactor.
Preferably, when the number of the gas-solid separation devices is more than or equal to 2, the first gas-solid separation device is arranged above the inside of the fluidized bed reactor and/or outside the fluidized bed reactor, and when the number of the gas-solid separation devices is more than one, the gas-solid separation devices can be partially arranged in the fluidized bed reactor and partially arranged outside the fluidized bed reactor.
Preferably, when the gas-solid separation device is arranged in the fluidized bed reactor, the solid material outlet of the gas-solid separation device is communicated to the upper part of the gas distributor in the fluidized bed reactor through a pipeline.
Preferably, when the gas-solid separation device is arranged outside the fluidized bed reactor, the solid material outlet of the gas-solid separation device is communicated to the upper part of the gas distributor in the fluidized bed reactor from the outside and/or the inside of the fluidized bed reactor through a pipeline, and the solid material outlet of the gas-solid separation device is communicated to the upper part of the gas distributor in the fluidized bed reactor from the outside and the inside of the fluidized bed reactor through a pipeline.
The specific extending position of the pipeline is positioned at a lower pressure position (namely, a position with lower pressure than other positions) above the gas distributor, so that the solid materials can smoothly flow down from the pipeline and be uniformly dispersed by the rising gas.
In the invention, gas products obtained by reaction in the fluidized bed reactor are primarily separated by a gas-solid separation device, and aluminum powder and the catalyst are separated and returned to the fluidized bed reactor for recycling.
As the solid material returning to the fluidized bed reactor forms a negative pressure zone above the gas distributor when entering the fluidized bed reactor, the turbulent motion of the gas flow is accelerated, the gas-solid mass transfer is further strengthened, the reaction rate is further improved, and the yield of the methyl aluminum chloride is finally improved. The solid material outlet of the gas-solid separation device is communicated to the upper part of a gas distributor in the fluidized bed reactor through a pipeline, the height of the gas-solid separation device needs to be controlled within a certain range, and if the gas-solid separation device is too high, the retention time of the solid materials in the fluidized bed is reduced; if the gas flow rate is too low, the gas flow rate and the gas pressure are high, so that the solid material cannot flow out easily.
Preferably, the gas treatment device comprises a degassing tower, and the degassing tower is used for removing methyl chloride in the dust-containing gas to obtain the product methyl aluminum chloride.
Preferably, a washing tower is arranged in front of the degassing tower in the gas treatment device, and a gas outlet is arranged at the top of the washing tower and is connected with the degassing tower.
Preferably, the bottom of the washing tower is provided with a solid residue-containing slurry outlet.
Preferably, a condenser is arranged outside the washing tower, a gas outlet at the top of the washing tower is connected with an inlet of the condenser, a liquid outlet of the condenser is connected with a material reflux port at the top of the washing tower, and a gas outlet of the condenser is connected with a gas inlet of the degassing tower.
Preferably, the bottom of the washing tower is provided with a reboiler.
Preferably, a product outlet is formed in the bottom of the washing tower, the material output from the product outlet is divided into two paths, one path returns to the washing tower through a reboiler, and the other path is sent to the methyl phosphorus dichloride synthesis unit. The opening of the product outlet is higher than the solid slag-containing slurry outlet.
Preferably, the degassing tower is provided with a gas outlet, and the gas outlet is connected with a methyl chloride conveying pipeline, namely, the methyl chloride separated from the degassing tower is returned to the fluidized bed reactor for recycling.
Preferably, the bottom of the degassing tower is provided with a reboiler.
Preferably, a product outlet is formed in the bottom of the degassing tower, the material output from the product outlet is divided into two paths, one path of the material returns to the degassing tower through a reboiler, and the other path of the material is sent to the methyl phosphorus dichloride synthesis unit.
As a preferable technical scheme of the invention, the methyl phosphorus dichloride synthesis unit further comprises a product separation device, and a material outlet of the methyl phosphorus dichloride synthesis device is connected with a material inlet of the product separation device;
preferably, the product separation unit is a distillation unit with a vacuum system.
As a preferable technical scheme of the invention, the methyl phosphite ester synthesis unit comprises a methyl phosphite ester synthesis device, a byproduct removal device and a product separation device which are sequentially connected, wherein a product methyl phosphorus dichloride obtained by the methyl phosphorus dichloride synthesis unit enters the methyl phosphite ester synthesis device in the methyl phosphite ester synthesis unit for synthesis reaction;
preferably, the methyl phosphite ester synthesis unit is any one of a reaction kettle, a tubular reactor or a packed tower or a combination of at least two of the following, typical but non-linear examples of the combination are: the combination of a reaction kettle and a tubular reactor, the combination of a tubular reactor and a packed tower, the combination of a reaction kettle, a tubular reactor and a packed tower and the like.
Preferably, the methyl phosphite synthesis device is provided with an alcohol inlet which is connected with an alcohol conveying pipeline.
Preferably, the de-byproduct device comprises a deacidification device.
In the invention, after the methyl phosphorus dichloride and the alcohol are mixed and reacted, the mixture enters a deacidification device to continuously react and remove byproduct hydrogen chloride, and the removed hydrogen chloride is absorbed by water to prepare hydrochloric acid.
Preferably, the material outlet of the methyl phosphite ester synthesis device is connected with the material inlet of the deacidification device.
Preferably, the deacidification apparatus is any one of a reaction kettle, a falling film evaporator or a tower reactor or a combination of at least two of the following, typical but non-limiting examples being: the combination of a reaction kettle and a falling-film evaporator, the combination of a falling-film evaporator and a tower reactor, the combination of a reaction kettle, a falling-film evaporator and a tower reactor and the like.
Preferably, the product separation device comprises at least one rectifying tower, but not limited to one rectifying tower, and the number of the rectifying towers can be 2, 3, 4 or 5 or more, so that the rectifying towers are alternately used to ensure the continuous operation of the whole system. In the invention, the top of the rectifying tower produces products, and the bottom of the rectifying tower produces byproducts.
Preferably, the product outlet of the byproduct removing device is connected with the material inlet of the rectifying tower.
Preferably, a condenser is arranged at the top of the rectifying tower.
Preferably, the condensate of the condenser is divided into two paths, one path returns to the rectifying tower, and the other path is connected with the storage tank.
Preferably, the bottom of the rectifying tower is provided with a reboiler.
Preferably, the material discharged from the reboiler is divided into two paths, one path is returned to the rectifying tower, and the other path is connected with the storage tank.
As a preferred technical scheme, the system comprises a methyl aluminum chloride synthesis unit, a methyl phosphorus dichloride synthesis unit and a methyl phosphite ester synthesis unit; the methyl aluminium chloride synthesis unit comprises a fluidized bed reactor and a separation unit which are connected in sequence, the separation unit comprises a gas-solid separation device and a gas treatment device which are connected in sequence, a material outlet at the top of the fluidized bed reactor is connected with a material inlet of the gas-solid separation device, the methyl phosphorus dichloride synthesis unit comprises a methyl phosphorus dichloride synthesis device and a product separation device which are connected in sequence, and the methyl phosphorus dichloride synthesis device is a closed reaction kettle; a product outlet of the gas treatment device in the separation unit is connected with a material inlet of the methyl phosphorus dichloride synthesis device, the methyl phosphite synthesis unit comprises a methyl phosphite synthesis device, a deacidification device and a rectification tower which are sequentially connected, and a product outlet of the product separation device in the methyl phosphorus dichloride synthesis unit is connected with a material inlet of the methyl phosphite synthesis device in the methyl phosphite synthesis unit;
the bottom of the fluidized bed reactor is provided with a gas material inlet, the side wall of the fluidized bed reactor is provided with a solid material inlet, the gas material inlet is connected with a chloromethane conveying pipeline, and heating equipment is arranged on the chloromethane conveying pipeline; a gas distributor is arranged above a gas material inlet at the bottom in the fluidized bed reactor, the opening rate of gas holes on the gas distributor is 0.1-15%, and the opening aperture is 3-8 mm; a heat exchanger is arranged in the fluidized bed reactor, the heat exchanger is arranged above the gas distributor, and the heat exchanger is any one or the combination of at least two of a U-shaped tube heat exchanger, a finger-shaped heat exchanger or a serpentine heat exchanger;
the gas outlet of the gas-solid separation device is connected with the inlet of the gas treatment device, and the gas-solid separation device is a cyclone separator; the gas-solid separation device is arranged above the inside of the fluidized bed reactor and/or outside the fluidized bed reactor, and a solid material outlet of the gas-solid separation device is communicated to the upper part of a gas distributor in the fluidized bed reactor from the outside and/or the inside of the fluidized bed reactor through a pipeline;
the gas treatment device comprises a washing tower and a degassing tower which are connected in sequence; a condenser is arranged outside the washing tower, a gas outlet at the top of the washing tower is connected with an inlet of the condenser, a liquid outlet of the condenser is connected with a material reflux port at the top of the washing tower, and a gas outlet of the condenser is connected with a gas inlet of the degassing tower; a reboiler is arranged at the bottom of the washing tower; a product outlet is arranged at the bottom of the washing tower, the material output from the product outlet is divided into two paths, one path returns to the washing tower through the reboiler, and the other path is sent to the methyl phosphorus dichloride synthesis unit; the degassing tower is provided with a gas outlet, and the gas outlet is connected with a chloromethane conveying pipeline; a reboiler and a product outlet are arranged at the bottom of the degassing tower, the material output from the product outlet is divided into two paths, one path returns to the degassing tower through the reboiler, and the other path is sent to the methyl phosphorus dichloride synthesis unit;
the product separation device is a distillation device with a vacuum system;
the methyl phosphite ester synthesis device is any one or the combination of at least two of a reaction kettle, a tubular reactor or a packed tower; the methyl phosphite ester synthesis device is provided with an alcohol inlet which is connected with an alcohol conveying pipeline; the deacidification device is any one or the combination of at least two of a reaction kettle, a falling film evaporator or a tower reactor; a condenser is arranged at the top of the rectifying tower, condensate of the condenser is divided into two paths, one path returns to the rectifying tower, and the other path is connected with a storage tank; a reboiler is arranged at the bottom of the rectifying tower; the material discharged from the reboiler is divided into two paths, one path is returned to the rectifying tower, and the other path is connected with the storage tank.
In a second aspect, the present invention provides a process for the preparation of a methylphosphite, the process comprising the steps of:
(a) carrying out gas-solid catalytic reaction on raw material aluminum, a catalyst and gasified chloromethane in a fluidized bed reactor to obtain mixed gas;
(b) separating the mixed gas obtained in the step (a) to obtain a methyl aluminum chloride product;
(c) reacting the methyl aluminum chloride product obtained in the step (b) with phosphorus trichloride in a methyl phosphorus dichloride synthesis deviceGeneration of ligand 3CH3PCl2·2AlCl3Then reacting with alkali metal halide to obtain methyl phosphorus dichloride;
(d) and (c) reacting the methyl phosphorus dichloride obtained in the step (c) with alcohol to obtain a methyl phosphite ester product.
As a preferred technical scheme of the invention, the method is carried out in the system.
The raw material aluminum in the step (a) is any one or a combination of at least two of solid particle aluminum, aluminum powder or aluminum-magnesium alloy, and typical but non-limiting examples of the combination are as follows: a combination of solid particles of aluminum and aluminum powder, a combination of aluminum powder and aluminum-magnesium alloy, a combination of solid particles of aluminum, aluminum powder and aluminum-magnesium alloy, and the like, with aluminum powder being preferred.
Preferably, the aluminum powder has an average particle size of 5to 400 mesh, for example, 5, 10, 50, 100, 150, 200, 250, 300, 350 or 400 mesh, but not limited to the recited values, and other values not recited within the range of the values are also applicable, preferably 20to 200 mesh.
Preferably, the catalyst in step (a) is any one or a combination of at least two of aluminum trichloride, aluminum trichloride complex, elementary halogen or hydrogen halide, and typical but non-limiting examples of the combination are as follows: combinations of aluminum trichloride and elemental halogen, combinations of aluminum trichloride and hydrogen halide, combinations of elemental halogen and hydrogen halide, and the like.
Preferably, the aluminum trichloride compound is a mixture of aluminum trichloride and methylaluminum dichloride and/or dimethylaluminum chloride, namely a mixture of aluminum trichloride and methylaluminum dichloride, a mixture of aluminum trichloride and dimethylaluminum chloride, and a mixture of aluminum trichloride, methylaluminum dichloride and dimethylaluminum chloride.
The invention adopts the mixture of methyl aluminum dichloride and/or dimethyl aluminum chloride and the aluminum trichloride as the catalyst, and can obviously reduce the initial initiation time of the reaction compared with the method of simply adding the aluminum trichloride.
Preferably, the mass ratio of the mixture of aluminum trichloride and methylaluminum dichloride and/or dimethylaluminum chloride is (100-1000): 1, for example 100:1, 200:1, 300:1, 400:1, 500:1, 600:1, 700:1, 800:1, 900:1 or 1000:1, but not limited to the recited values, and other values within this range are also applicable, preferably (200-500): 1.
Preferably, the mass ratio of the raw material aluminum and the catalyst in the step (a) is (100 to 1000):1, for example, 100:1, 200:1, 300:1, 400:1, 500:1, 600:1, 700:1, 800:1, 900:1, 1000:1, etc., but not limited to the enumerated values, and other non-enumerated values within the numerical range are also applicable, preferably (200 to 500): 1.
Preferably, the gasified methyl chloride of step (a) is fed to the fluidized bed reactor at a flow rate of 0.2m/s to 40m/s, such as 0.2m/s, 0.5m/s, 1m/s, 3m/s, 5m/s, 10m/s, 15m/s, 20m/s, 25m/s, 30m/s, 35m/s or 40m/s, etc., but not limited to the values listed, other values not listed in this range of values being equally applicable, preferably 0.2m/s to 10 m/s.
Preferably, the methyl chloride gasified in step (a) is fed into a fluidized bed reactor and subjected to gas distribution through a gas distributor.
Preferably, the reaction temperature of the gas-solid catalytic reaction in step (a) is 150 ℃ to 300 ℃, for example 150 ℃, 170 ℃, 180 ℃, 190 ℃, 200 ℃, 210 ℃, 220 ℃, 230 ℃, 250 ℃ or 300 ℃, but not limited to the recited values, and other values not recited within this range are equally applicable, preferably 160 ℃ to 200 ℃.
Preferably, the pressure drop across the bed in the fluidized bed reactor in step (a) is in the range of from 1kPa to 50kPa, such as, for example, 1kPa, 5kPa, 10kPa, 15kPa, 20kPa, 25kPa, 30kPa, 35kPa, 40kPa, 45kPa, or 50kPa, but is not limited to the values recited, and other values not recited in this range of values are equally applicable, preferably 1kPa to 10 kPa.
Preferably, the gas-solid catalytic reaction of step (a) is carried out under a protective atmosphere.
Preferably, the protective atmosphere is any one of nitrogen, helium, neon or argon or a combination of at least two of these, typical but non-limiting examples being: a combination of nitrogen and helium, a combination of neon and argon, a combination of nitrogen, helium and neon, a combination of helium, neon and argon, and the like, with nitrogen being preferred.
Preferably, the separation treatment of step (b) comprises gas-solid separation, washing and degassing treatment.
Preferably, the gas-solid separation is a cyclonic separation process.
Preferably, the raw material aluminum and the catalyst are obtained by gas-solid separation and are returned to the fluidized bed reactor for gas-solid phase catalytic reaction.
Preferably, the gas after gas-solid separation is washed to obtain a product and washed gas, and the washed gas is subjected to degassing treatment.
Preferably, the degassing treatment is carried out to obtain methyl aluminum chloride and methyl chloride, and the methyl chloride returns to the fluidized bed reactor to carry out gas-solid phase catalytic reaction.
Preferably, the chloromethane is compressed, condensed, gasified and heated and then returns to the fluidized bed reactor for gas-solid phase catalytic reaction.
Preferably, the separation treatment is carried out under a protective atmosphere.
Preferably, the protective atmosphere is any one of nitrogen, helium, neon or argon or a combination of at least two of these, typical but non-limiting examples being: a combination of nitrogen and helium, a combination of neon and argon, a combination of nitrogen, helium and neon, a combination of helium, neon and argon, and the like, with nitrogen being preferred.
Preferably, the methyl aluminium chloride of step (b) is a mixture of methyl aluminium dichloride and dimethyl aluminium chloride.
As a preferred embodiment of the present invention, the reaction temperature of the reaction of the methyl aluminum chloride product and phosphorus trichloride in the step (c) is-10 ℃ to 80 ℃, for example-10 ℃, 0 ℃, 5 ℃, 10 ℃, 20 ℃, 30 ℃, 40 ℃, 50 ℃, 60 ℃, 70 ℃ or 80 ℃, but is not limited to the recited values, and other values not recited in the numerical range are also applicable.
Preferably, the alkali metal halide comprises any one of sodium chloride, potassium bromide, potassium iodide or sodium bromide, or a combination of at least two of these, typical but non-limiting examples being: combinations of sodium chloride and potassium chloride, potassium chloride and sodium bromide, potassium bromide and potassium iodide, potassium iodide and sodium bromide, sodium chloride, potassium chloride and sodium bromide, potassium chloride, potassium bromide, potassium iodide and sodium bromide, and the like.
Preferably, the molar ratio of the methyl aluminum chloride product to the phosphorus trichloride in the step (c) is 1 (3-15), such as 1:3, 1:5, 1:7, 1:10, 1:13 or 1:15, but not limited to the recited values, and other values not recited in the range of the values are also applicable.
Preferably, the molar ratio of the methyl aluminum chloride product to the alkali metal halide in step (c) is 1 (2) to 20, such as 1:2, 1:4, 1:6, 1:8, 1:10, 1:12, 1:14, 1:16, 1:18, or 1:20, but not limited to the recited values, and other values not recited in this range are also applicable.
Preferably, 3CH in step (c)3PCl2·2AlCl3The reaction temperature with the alkali metal halide is 50 ℃ to 220 ℃, for example, 50 ℃, 70 ℃, 100 ℃, 120 ℃, 140 ℃, 160 ℃, 180 ℃, 200 ℃ or 220 ℃, etc., but is not limited to the recited values, and other values not recited in the numerical range are also applicable.
Preferably, 3CH in step (c)3PCl2·2AlCl3The reaction pressure with the alkali metal halide is 2torr to 100torr, for example, 2torr, 5torr, 10torr, 20torr, 30torr, 40torr, 50torr, 60torr, 70torr, 80torr, 90torr, 100torr, etc., but is not limited to the above-mentioned values, and other values not mentioned in this range are also applicable.
Preferably, the alcohol in step (d) is a liquid alcohol.
Preferably, in step (d), the alcohol is any one of methanol, ethanol, propanol, isopropanol, n-butanol or isobutanol, or a combination of at least two thereof, as typical but non-limiting examples: a combination of methanol and ethanol, a combination of ethanol and propanol, a combination of isopropanol and n-butanol, a combination of n-butanol and isobutanol, a combination of methanol, ethanol and propanol, a combination of propanol, isopropanol and n-butanol, a combination of isopropanol, n-butanol and isobutanol, a combination of methanol, ethanol, propanol and isopropanol, a combination of propanol, isopropanol, n-butanol and isobutanol, and the like.
Preferably, the molar ratio of methyl phosphorus dichloride and alcohol in step (d) is 1 (0.5-10), such as 1:0.5, 1:1, 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, or 1:10, but not limited to the recited values, and other values not recited within this range are equally applicable, preferably 1 (1-4).
Preferably, the alkyl group connected to the ester group in the methyl phosphite in the step (d) is a C1-C4 straight-chain alkane and/or a C1-C4 side-chain alkane, wherein the C1-C4 side-chain alkane refers to a side-chain-containing alkane with 1-4 carbon atoms. The number of carbons in the alkyl group may be 1,2, 3, or 4.
Preferably, the alkyl group attached to the ester group is any one of methyl, ethyl, propyl, isopropyl, n-butyl or isobutyl or a combination of at least two of these, typical but non-limiting examples being: a combination of methyl and ethyl, a combination of propyl and isopropyl, a combination of ethyl and propyl, a combination of isopropyl and n-butyl, and the like.
Preferably, when the methylphosphite product is a methylphosphite monoester, the molar ratio of methylphosphite to alcohol is 1 (1-1.2), for example 1:1, 1:1.03, 1:1.05, 1:1.07, 1:1.1, 1:1.13, 1:1.15, 1:1.17 or 1:1.2, etc., but not limited to the recited values, and other values not recited in the range of values are equally applicable. Wherein, the methyl phosphite monoester comprises methyl phosphite, ethyl methyl phosphite, propyl methyl phosphite, isopropyl methyl phosphite, n-butyl methyl phosphite or isobutyl methyl phosphite, etc.
Preferably, when the methylphosphite product is a methylphosphite diester, the molar ratio of methylphosphite to alcohol is 1 (2-2.4), for example 1:2, 1:2.05, 1:2.1, 1:2.15, 1:2.2, 1:2.25, 1:2.3, 1:2.35 or 1:2.4, etc., but not limited to the recited values, and other values not recited in the range of values are equally applicable. Wherein, the methyl phosphite diester comprises dimethyl methyl phosphite, diethyl methyl phosphite, dipropyl methyl phosphite, diisopropyl methyl phosphite, di-n-butyl methyl phosphite or diisobutyl methyl phosphite and the like.
Preferably, the reaction temperature of the reaction in step (d) is 0 ℃ to 100 ℃, such as 1 ℃, 5 ℃, 10 ℃, 15 ℃, 20 ℃, 25 ℃, 30 ℃, 40 ℃, 50 ℃, 60 ℃, 70 ℃, 80 ℃, 90 ℃ or 100 ℃, but not limited to the recited values, and other unrecited values within this range are equally applicable, preferably 10 ℃ to 40 ℃.
Preferably, the reaction pressure of the reaction in step (d) is between 0MPa and-0.1 MPa, such as-0.005 MPa, -0.01MPa, -0.0015MPa, -0.02MPa, -0.03MPa, -0.04MPa, -0.05MPa, -0.06MPa, -0.07MPa, -0.08MPa, -0.09MPa or-0.099 MPa, but not limited to the values listed, and other values not listed within this range of values are equally applicable, preferably-0.05 MPa to-0.095 MPa.
Preferably, the material obtained by reacting methyl phosphorus dichloride and alcohol in the step (d) is deacidified and rectified in sequence to obtain the methyl phosphite ester product.
Preferably, the deacidification temperature is 0 ℃ to 100 ℃, such as 1 ℃, 5 ℃, 10 ℃, 15 ℃, 20 ℃, 25 ℃, 30 ℃, 35 ℃, 40 ℃, 45 ℃, 50 ℃, 55 ℃, 60 ℃, 65 ℃, 70 ℃, 75 ℃, 80 ℃, 85 ℃, 90 ℃, 95 ℃ or 100 ℃, but not limited to the enumerated values, and other non-enumerated values in the numerical range are equally applicable, preferably 40 ℃ to 80 ℃. The deacidification temperature is preferably 40-80 ℃, and the deacidification temperature is favorable for removing low-boiling-point impurities such as hydrogen chloride, alcohol and the like in the temperature range.
Preferably, the deacidification pressure is between 0MPa and-0.1 MPa, such as-0.005 MPa, -0.01MPa, -0.0015MPa, -0.02MPa, -0.03MPa, -0.04MPa, -0.05MPa, -0.06MPa, -0.07MPa, -0.08MPa, -0.09MPa or-0.099 MPa, but not limited to the values listed, and other values not listed within this range are equally applicable, preferably-0.05 MPa to-0.095 MPa.
Preferably, the temperature of the rectification is between 0 ℃ and 180 ℃, such as 1 ℃, 10 ℃, 30 ℃, 50 ℃, 70 ℃, 80 ℃, 90 ℃, 100 ℃, 110 ℃, 120 ℃, 130 ℃, 140 ℃, 150 ℃, 160 ℃, 170 ℃ or 180 ℃ and the like, but is not limited to the recited values, and other values not recited in the range of values are equally applicable, preferably between 80 ℃ and 160 ℃. The rectification temperature is preferably 80-160 ℃, and the separation of products and high-boiling-point impurities is facilitated in the temperature range.
Preferably, the pressure of the distillation is between 0MPa and-0.1 MPa, such as-0.005 MPa, -0.01MPa, -0.0015MPa, -0.02MPa, -0.03MPa, -0.04MPa, -0.05MPa, -0.06MPa, -0.07MPa, -0.08MPa, -0.09MPa or-0.099 MPa, but not limited to the values listed, and other values not listed within this range of values are equally applicable, preferably-0.05 MPa to-0.095 MPa.
As a preferred technical scheme of the invention, the method comprises the following steps:
(a') carrying out gas-solid catalytic reaction on aluminum powder serving as a raw material, a catalyst and gasified chloromethane in a fluidized bed reactor (1), wherein the reaction temperature is 150-300 ℃, the pressure drop of a bed layer in the fluidized bed reactor is 1-50 kPa, and the gas-solid catalytic reaction is carried out in a protective atmosphere to obtain a mixed gas, wherein the catalyst is any one or the combination of at least two of aluminum trichloride, an aluminum trichloride compound, a halogen simple substance or hydrogen halide, the mass ratio of the aluminum serving as the raw material to the catalyst is (100-1000): 1, and the flow rate of the gasified chloromethane is 0.2-40 m/s;
(b ') carrying out gas-solid separation, washing and degassing treatment on the mixed gas obtained in the step (a') to obtain a methyl aluminum chloride product; the solid materials obtained by gas-solid separation are raw material aluminum and a catalyst, the raw material aluminum and the catalyst return to a fluidized bed reactor to carry out gas-solid phase catalytic reaction, methyl chloride and methyl chloride are obtained by degassing treatment, the methyl chloride returns to the fluidized bed reactor to carry out gas-solid phase catalytic reaction, the methyl chloride and the methyl chloride are obtained by degassing treatment, and the methyl chloride returns to the fluidized bed reactor to carry out gas-solid phase catalytic reaction;
(c ') reacting the mixture of the methyl aluminum dichloride product obtained in the step (b') and dimethyl aluminum chloride with phosphorus trichloride in a methyl phosphorus dichloride synthesis device to generate a ligand 3CH3PCl2·2AlCl3And reacting with alkali metal halide to obtain methyl phosphorus dichloride, wherein the molar ratio of a methyl aluminum chloride product to phosphorus trichloride is 1 (3-15), the molar ratio of the methyl aluminum chloride product to the alkali metal halide is 1 (2-20), and 3CH3PCl2·2AlCl3The reaction temperature of the reaction with the alkali metal halide is 50 ℃ to 220 ℃, and the reaction pressure is 2torr to 100 torr;
(d ') reacting the methyl phosphorus dichloride obtained in the step (c') with alcohol according to a molar ratio of 1 (0.5-10), wherein the reaction temperature is 10-40 ℃, the reaction pressure is-0.05 MPa-0.095 MPa, so as to obtain a reacted material, deacidifying the reacted material under the conditions that the temperature is 40-80 ℃, and the pressure is-0.05 MPa-0.095 MPa, so as to remove a byproduct hydrogen chloride, and rectifying the deacidified material under the conditions that the temperature is 80-160 ℃, and the pressure is-0.05 MPa-0.095 MPa, so as to obtain a methyl phosphite ester product.
Compared with the prior art, the invention has the following beneficial effects:
(1) according to the invention, aluminum powder and chloromethane are used as raw materials, and a catalyst is subjected to gas-solid catalytic reaction in a fluidized bed reactor under the condition of fluidization, and methyl aluminum chloride is obtained through separation, so that the mass transfer process is increased, and the reaction rate is improved;
(2) the invention synthesizes the methyl phosphorus dichloride in the closed reaction kettle, which is beneficial to improving the simplicity and convenience of the synthesis operation of the methyl phosphorus dichloride;
(3) the method can achieve high yield in a short time, so that the yield of the methyl aluminum chloride is 90-95%, the yield of the methyl phosphorus dichloride is 98%, and the yield of the methyl phosphite ester product is further improved to 95%;
(4) the invention adopts the fluidized bed reactor to realize continuous operation, improves the production efficiency and improves the production efficiency by 2to 3 times compared with the prior intermittent mode of adopting a high-pressure reaction kettle and the like.
Drawings
FIG. 1 is a schematic diagram showing the structure of a system for producing methylphosphites in example 1 of the present invention;
FIG. 2 is a schematic view showing the structure of a fluidized bed reactor in example 1 of the present invention;
FIG. 3 is a schematic view showing the structure of a fluidized bed reactor in example 2 of the present invention;
the device comprises a fluidized bed reactor 1, a gas-solid separation device 2, a washing tower 3, a degassing tower 4, a gas distributor 5, a phosphorus methyl dichloride synthesis device 6, a product separation device 7, a methyl phosphite ester synthesis device 8, a deacidification device 9 and a rectification tower 10.
Detailed Description
In order to better illustrate the present invention and facilitate the understanding of the technical solutions of the present invention, the present invention is further described in detail below. The following examples are merely illustrative of the present invention and do not represent or limit the scope of the claims, which are defined by the claims.
The invention provides a system for preparing methyl phosphite ester and a preparation method thereof, wherein the system comprises a methyl aluminum chloride synthesis unit, a methyl phosphorus dichloride synthesis unit and a methyl phosphite ester synthesis unit; the methyl aluminium chloride synthesis unit comprises a fluidized bed reactor 1 and a separation unit which are connected in sequence, the methyl phosphorus dichloride synthesis unit comprises a methyl phosphorus dichloride synthesis device 6, and the methyl phosphorus dichloride synthesis device 6 is a closed reaction kettle; and the methyl aluminum chloride obtained by the methyl aluminum chloride synthesis unit enters a methyl phosphorus dichloride synthesis unit, and the methyl phosphorus dichloride obtained by the methyl phosphorus dichloride synthesis unit enters a methyl phosphite synthesis unit.
The preparation method comprises the following steps:
(a) carrying out gas-solid catalytic reaction on raw material aluminum, a catalyst and gasified chloromethane in a fluidized bed reactor 1 to obtain mixed gas;
(b) separating the mixed gas obtained in the step (a) to obtain a methyl aluminum chloride product;
(c) reacting the methyl aluminum chloride product obtained in the step (b) with phosphorus trichloride in a methyl phosphorus dichloride synthesis device 6 to generate a ligand 3CH3PCl2·2AlCl3Then reacting with alkali metal halide to obtain methyl phosphorus dichloride;
(d) and (c) reacting the methyl phosphorus dichloride obtained in the step (c) with alcohol to obtain a methyl phosphite ester product.
The following are typical but non-limiting examples of the invention:
example 1:
this example provides a system for preparing methyl phosphite, as shown in fig. 1, the system includes a methyl aluminum chloride synthesis unit, a methyl phosphorus dichloride synthesis unit, and a methyl phosphite synthesis unit; the methyl aluminum chloride synthesis unit comprises a fluidized bed reactor 1 and a separation unit which are sequentially connected, the methyl phosphorus dichloride synthesis unit comprises a methyl phosphorus dichloride synthesis device 6, a product of the closed reaction kettle fluidized bed reactor 1 of the methyl phosphorus dichloride synthesis device 6 enters the separation unit for separation, methyl aluminum chloride obtained by separation of the separation unit enters the methyl phosphorus dichloride synthesis device 6 in the methyl phosphorus dichloride synthesis unit for reaction, and methyl phosphorus dichloride obtained by the methyl phosphorus dichloride synthesis unit enters the methyl phosphite synthesis unit;
the bottom of the fluidized bed reactor 1 is provided with a gas material inlet, the side wall of the fluidized bed reactor is provided with a solid material inlet, a catalyst and raw material aluminum are introduced into the solid material inlet, and the gas material inlet is connected with a chloromethane conveying pipeline; a gas distributor 5 is arranged above a gas material inlet at the bottom in the fluidized bed reactor 1; the opening rate of the air holes on the gas distributor 5 is 3.6 percent, the opening aperture is 5 mm-6 mm, the openings are circular and are distributed in a triangular shape; a finger-shaped pipe heat exchanger is arranged in the fluidized bed reactor 1, and is arranged above the gas distributor 6 as shown in figure 2;
the separation unit comprises a gas-solid separation device 2 and a gas treatment device which are sequentially connected, a material outlet of the fluidized bed reactor 1 is connected with a material inlet of the gas-solid separation device 2, a gas outlet of the gas-solid separation device 2 is connected with an inlet of the gas treatment device, the gas-solid separation device 2 is arranged outside the fluidized bed reactor 1, and a solid material outlet of the gas-solid separation device 2 is communicated to the position above a gas distributor in the fluidized bed reactor 1 from the inside of the fluidized bed reactor 1 through a pipeline; the gas treatment device comprises a washing tower 3 and a degassing tower 4 which are connected in sequence; a gas outlet of the gas-solid separation device 2 is connected with an inlet of the washing tower 3, and the bottom of the washing tower 3 is provided with a solid residue-containing slurry outlet; a condenser is arranged outside the washing tower 3, a gas outlet at the top of the washing tower 3 is connected with an inlet of the condenser, a liquid outlet of the condenser is connected with a material reflux port at the top of the washing tower 3, and a gas outlet of the condenser is connected with a gas inlet of the degassing tower 4; a gas outlet of the degassing tower 4 is connected with a chloromethane conveying pipeline, a reboiler is arranged at the bottom of the degassing tower 4, a product outlet is arranged at the bottom of the degassing tower 4, the material output by the product outlet is divided into two paths, one path returns to the degassing tower 4 through the reboiler, and the other path is sent to a methyl phosphorus dichloride synthesis unit;
the methyl phosphorus dichloride synthesis unit also comprises a product separation device 7, wherein the product separation device 7 is a distillation device with a vacuum system; a material outlet of the methyl phosphorus dichloride synthesizing device 6 is connected with a material inlet of the product separating device 7, and a product outlet of the product separating device 7 is connected with a material inlet of the methyl phosphite synthesizing device 8;
the methyl phosphite ester synthesis unit comprises a methyl phosphite ester synthesis device 8, a byproduct removal device and a product separation device which are sequentially connected, wherein the methyl phosphite ester synthesis device 8 is a reaction kettle, an alcohol inlet is formed in the reaction kettle and connected with an alcohol conveying pipeline, the byproduct removal device comprises a deacidification device 9, the deacidification device 9 is the reaction kettle, the product separation device comprises a rectifying tower 10, a condenser is arranged at the top of the rectifying tower 10, condensate of the condenser is divided into two paths, one path returns to the rectifying tower, and the other path is connected with a storage tank; the tower bottom of the rectifying tower 10 is provided with a reboiler, the discharge of the reboiler is divided into two paths, one path returns to the rectifying tower 10, and the other path is connected with a storage tank.
Example 2:
this example provides a system for the preparation of methyl phosphites, with reference to the system configuration of example 1, except that: the opening rate of the air holes on the gas distributor 5 is 13.8%, a U-shaped heat exchanger is arranged in the fluidized bed reactor 1, and as shown in figure 3, the U-shaped heat exchanger is arranged above the gas distributor 6; the gas-solid separation device 2 is arranged outside the fluidized bed reactor 1, and a solid material outlet of the gas-solid separation device is communicated to the upper part of a gas distributor in the fluidized bed reactor 1 from the outside of the fluidized bed reactor 1 through a pipeline; the methyl phosphite ester synthesis device 8 is a tubular reactor, and the deacidification device 9 is a falling film evaporator.
Example 3:
this example provides a system for the preparation of methyl phosphites, with reference to the system configuration of example 1, except that: the aperture ratio of the air holes on the gas distributor 5 is 2.8%, the aperture of the open holes is 3-4 mm, the open holes on the gas distributor 6 are distributed in a square shape, and the heat exchanger is a coiled pipe heat exchanger; the gas-solid separation device 2 is arranged above the inside of the fluidized bed reactor 1, and a solid material outlet of the gas-solid separation device is communicated to the upper part of a gas distributor in the fluidized bed reactor 1 from the inside of the fluidized bed reactor 1 through a pipeline; the methyl phosphite ester synthesis device 8 is a tubular reactor, and the deacidification device 9 is a falling film evaporator.
Example 4:
this example provides a system for the preparation of methyl phosphites, with reference to the system configuration of example 1, except that: the aperture ratio of the gas distributor 6 is 0.2 percent, the aperture of the open pores is 7 mm-8 mm, and the open pores on the gas distributor 6 are distributed in a diamond shape; the number of the gas-solid separation devices 2 is 2, one of the gas-solid separation devices is arranged above the inside of the fluidized bed reactor 1, the solid material outlet of the gas-solid separation device is communicated to the upper part of the gas distributor in the fluidized bed reactor 1 from the inside of the fluidized bed reactor 1 through a pipeline, the other gas-solid separation device is arranged outside the fluidized bed reactor 1, and the solid material outlet of the gas-solid separation device is communicated to the upper part of the gas distributor in the fluidized bed reactor 1 from the outside of the fluidized bed reactor 1 through a pipeline; the methyl phosphite ester synthesizing device 8 is a packed tower, and the deacidification device 9 is a tower reactor.
Example 5:
the embodiment provides a preparation method of diethyl methylphosphonite, which adopts the system in embodiment 1 to prepare the diethyl methylphosphonite, and specifically comprises the following steps:
(a) introducing a mixture of aluminum powder with the mesh number of 60, aluminum trichloride as a catalyst, methyl aluminum dichloride and dimethyl aluminum chloride (the mass ratio of the aluminum powder to the catalyst is 400:1) into a fluidized bed reactor 1 from a solid material inlet of the fluidized bed reactor 1, heating gasified chloromethane, then feeding the heated chloromethane into the fluidized bed reactor 1, and carrying out gas-solid catalytic reaction at the reaction temperature of 170-175 ℃, the pressure drop of a bed layer of 3-5 kPa and the operating flow rate of the chloromethane of 0.4m/s to obtain a mixed gas, wherein the mixed gas is a generated synthesis gas and an unreacted chloromethane gas, and raw materials of aluminum and the catalyst are also entrained;
(b) the mixed gas obtained in the step (a) enters a gas-solid separation device 2 for gas-solid separation, the separated raw material aluminum and a catalyst return to a fluidized bed reactor 1 for gas-solid phase catalytic reaction, the separated gas enters a washing tower 3 for washing, the washed gas enters a degassing tower 4 for dechlorination methane treatment, a methyl aluminum chloride product and methyl chloride are obtained, the methyl chloride returns to the fluidized bed reactor 1 for gas-solid phase catalytic reaction, and the methyl aluminum chloride product is a mixture of methyl aluminum dichloride and dimethyl aluminum chloride;
(c) reacting the methyl aluminum chloride product obtained in the step (b) with phosphorus trichloride in a methyl phosphorus dichloride synthesis device 6 at 0-5 ℃ to generate a ligand 3CH3PCl2·2AlCl3Then reacting with sodium chloride to obtain methyl phosphorus dichloride, wherein the reaction temperature is 80-90 ℃, and the reaction pressure is 5-10 torr;
(d) introducing 1000kg/h of methyl phosphorus dichloride (with the purity of 98 wt%) obtained in the step (c) and 760kg/h of ethanol (with the purity of 99 wt%) into a methyl phosphite ester synthesis device 8, and carrying out mixing reaction, wherein the reaction temperature is controlled to be 20-25 ℃, and the reaction pressure is-0.08 MPa, so as to obtain a reacted material; the reacted materials firstly enter a deacidification device 9 to remove byproduct hydrogen chloride, the deacidification temperature is 50-60 ℃, the deacidification pressure is-0.08 MPa, and then the reacted materials enter a rectifying tower 3 to be rectified, the rectifying temperature is 155-160 ℃, and the pressure is-0.085 MPa, so that a product diethyl methylphosphonite is obtained;
in this example, the purity of the rectified diethyl methylphosphonite product can reach more than 98 wt%, the yield of methylaluminum chloride can reach 95%, the yield of methylphosphorus dichloride can reach 98%, and the yield of diethyl methylphosphonite is 92%.
Example 6:
this example provides a process for the preparation of monoethyl methylphosphonite using the system of example 2, the specific procedure being as described in example 5, except that:
in the step (a), the mesh number of the aluminum powder is 325 meshes, the mass ratio of the aluminum powder to the catalyst is 250:1, the reaction temperature is 160-165 ℃, the pressure drop of a bed layer is 10-15 kPa, and the operation flow rate of methyl chloride is 0.25 m/s;
reacting at 20-25 deg.C to generate ligand 3CH in step (b)3PCl2·2AlCl3Then reacting with potassium chloride, and separating to obtain methyl phosphorus dichloride, wherein the reaction temperature is 115-125 ℃, and the reaction pressure is 50-60 torr;
in the step (c), the molar ratio of the methyl phosphorus dichloride to the ethanol is 1:1.05, the reaction temperature is 25-30 ℃, the reaction pressure is-0.07 Mpa, the primary deacidification temperature is 55-60 ℃, the primary deacidification pressure is-0.075 Mpa, the secondary deacidification temperature is 60-65 ℃, and the secondary deacidification pressure is-0.08 Mpa; then the mixture enters a rectifying tower 3 for rectification at the temperature of 80-90 ℃ and under the pressure of-0.098 Mpa;
in this example, the purity of the ethyl methylphosphonous acid product after rectification can reach more than 95 wt%, the yield of methyl aluminum chloride can reach 92%, the yield of methyl phosphorus dichloride can reach 91%, and the yield of ethyl methylphosphonous acid can reach 88%.
Example 7:
this example provides a process for the preparation of dimethyl methylphosphonite using the system of example 3, the specific procedure being as described in example 5, except that:
in the step (a), the mesh number of the aluminum powder is 400 meshes, the mass ratio of the aluminum powder to the catalyst is 350:1, the reaction temperature is 175-180 ℃, the pressure drop of a bed layer is 45-50 kPa, and the operation flow rate of the chloromethane is 4.5 m/s;
reacting at 55-60 ℃ in step (b) to generate ligand 3CH3PCl2·2AlCl3Then reacting with sodium bromide, and separating to obtain methyl phosphorus dichloride, wherein the reaction temperature is 165-175 ℃, and the reaction pressure is 80-90 torr;
in the step (c), the molar ratio of the methyl phosphorus dichloride to the methanol is 1:2.4, the reaction temperature is 35-40 ℃, the reaction pressure is-0.05 Mpa, the primary deacidification temperature is 45-50 ℃, the primary deacidification pressure is-0.055 Mpa, the secondary deacidification temperature is 60-65 ℃, and the secondary deacidification pressure is-0.06 Mpa; then the mixture enters a rectifying tower 3 for rectification at the temperature of 100-110 ℃ and the pressure of-0.05 Mpa;
in this example, the purity of the rectified dimethyl methylphosphonite product can reach more than 96 wt%, the yield of methyl aluminum chloride can reach 95%, the yield of methyl phosphorus dichloride can reach 90%, and the yield of dimethyl methylphosphonite is 87%.
Example 8:
this example provides a process for the preparation of monomethyl methylphosphonite using the system of example 4, the procedure being as described in example 5, except that:
in the step (a), the mesh number of the aluminum powder is 120 meshes, the mass ratio of the aluminum powder to the catalyst is 500:1, the reaction temperature is 150-155 ℃, the pressure drop of a bed layer is 1-3 kPa, and the operation flow rate of the chloromethane is 0.2 m/s;
reacting at-5 deg.C to 0 deg.C in step (b) to produce ligand 3CH3PCl2·2AlCl3Then reacting with potassium bromide, and separating to obtain methyl phosphorus dichloride, wherein the reaction temperature is 185-195 ℃, and the reaction pressure is 85-95 torr;
in the step (c), the molar ratio of the methyl phosphorus dichloride to the methanol is 1:1.15, the reaction temperature is 25-30 ℃, the reaction pressure is-0.065 Mpa, the primary deacidification temperature is 45-50 ℃, the primary deacidification pressure is-0.055 Mpa, the secondary deacidification temperature is 60-65 ℃, and the secondary deacidification pressure is-0.06 Mpa; then the mixture enters a rectifying tower 3 for rectification at the temperature of 80-90 ℃ and under the pressure of-0.07 Mpa;
in this example, the purity of the methyl methylphosphonous acid product after rectification can reach more than 95 wt%, the yield of methyl aluminum chloride can reach 93%, the yield of methyl phosphorus dichloride can reach 89%, and the yield of methyl methylphosphonous acid can reach 85%.
Example 9:
this example provides a process for the preparation of mono-n-butyl methylphosphonite using the system of example 4, the specific procedure being as described in example 5, except that:
in the step (a), the mesh number of the aluminum powder is 20 meshes, the mass ratio of the aluminum powder to the catalyst is 200:1, the reaction temperature is 285-290 ℃, and the pressure drop of a bed layer is 15-20 kPa;
reacting at 25-30 ℃ in step (b) to generate ligand 3CH3PCl2·2AlCl3Then reacting with potassium iodide, and separating to obtain methyl phosphorus dichloride at the reaction temperature of 135-145 ℃ and the reaction pressure of 60-70 torr;
in the step (c), the molar ratio of the methyl phosphorus dichloride to the n-butanol is 1:1.2, the reaction temperature is 35-40 ℃, the reaction pressure is-0.085 Mpa, the primary deacidification temperature is 70-75 ℃, the primary deacidification pressure is-0.075 Mpa, the secondary deacidification temperature is 75-80 ℃, and the secondary deacidification pressure is-0.085 Mpa; then the mixture enters a rectifying tower 3 for rectification at the temperature of between 150 and 160 ℃ and under the pressure of-0.09 Mpa;
in this example, the purity of the rectified mono-n-butyl methylphosphonous acid product can reach more than 98 wt%, the yield of methyl aluminum chloride can reach 94%, the yield of methyl phosphorus dichloride can reach 90%, and the yield of mono-n-butyl methylphosphonous acid can reach 88%.
Comparative example 1:
this comparative example provides a system for producing diethyl methylphosphonite and a process for producing the same, the system being constructed as in example 1 except that a high-pressure reactor was used as a reactor in place of the fluidized bed reactor 1; the raw material aluminum, the catalyst and the gasified chloromethane are reacted in a high-pressure reaction kettle, the preparation method thereof refers to the method in example 5, the mixture of the methyl aluminum dichloride and the dimethyl aluminum chloride is obtained by the reaction, the obtained mixture of the methyl aluminum dichloride and the dimethyl aluminum chloride is reacted with the phosphorus trichloride to generate the ligand 3CH3PCl2·2AlCl3Then reacting with sodium chloride to obtain methyl phosphorus dichloride, and reacting the methyl phosphorus dichloride with ethanol to prepare diethyl methylphosphonite.
In this comparative example, the purity of the diethyl methylphosphonite product after rectification was only 95% by weight, the yield of methylaluminium chloride was only 85%, the yield of methylphosphonium dichloride was only 82%, and the yield of diethyl methylphosphonite was only 80%.
Comparative example 2:
this comparative example provides a system for producing diethyl methylphosphonite and a process for producing the same, the system being constructed as in example 1 except that the methyl aluminum chloride synthesis unit does not include a separation unit; the preparation method was as described in example 5, except that the separation treatment was not performed.
In this comparative example, the purity of the diethyl methylphosphonite product after rectification was only 95% by weight, the yield of methylaluminium chloride was only 89%, the yield of methylphosphonium dichloride was only 85%, and the yield of diethyl methylphosphonite was only 86%.
Comparative example 3:
this comparative example provides a system for producing diethyl methylphosphonite and a process for producing the same, the system being constructed as in example 1 except that the apparatus 6 for synthesizing methylphosphonous dichloride is a conventional reaction vessel; the preparation method is as in example 5.
In this comparative example, the purity of the diethyl methylphosphonite product after rectification was only 96% by weight, the yield of methylphosphonous dichloride was only 83% and the yield of diethyl methylphosphonite was only 87%.
Comparative example 4:
this comparative example provides a system for producing diethyl methylphosphonite and a process for producing the same, the system being constructed in accordance with the system of example 1 except that a stirred bed was used as a reactor in place of the fluidized bed reactor 1; the preparation method is as in example 5.
In this comparative example, the purity of the diethyl methylphosphonite product after rectification was only 96 wt%, the yield of methylaluminium chloride was only 88%, the yield of methylphosphonium dichloride was only 84%, and the yield of diethyl methylphosphonite was only 85%.
Comparative example 4:
this comparative example provides a system for preparing diethyl methylphosphonite and a process for preparing the same, the system configuration being referenced to the system configuration of example 1; the preparation is as in example 5, with the only difference that: the reaction temperature of the gas-solid catalytic reaction in the step (a) is 120 ℃ (namely less than 150 ℃, and the reaction temperature is too low).
In the comparative example, the gas-solid catalytic reaction temperature is too low, so that the reaction is incomplete, the selectivity is reduced, and the reaction efficiency is low, so that the purity of the rectified diethyl methylphosphonite product is only 95 wt%, the yield of the methylaluminium chloride is only 60%, the yield of the methylphosphonium dichloride is only 82%, and the yield of the diethyl methylphosphonite is only 85%.
Comparative example 5:
this comparative example provides a system for preparing diethyl methylphosphonite and a process for preparing the same, the system configuration being referenced to the system configuration of example 1; the preparation is as in example 5, with the only difference that: the reaction temperature of the gas-solid catalytic reaction in the step (a) is 320 ℃ (namely more than 300 ℃, and the reaction temperature is too high).
In the comparative example, the gas-solid catalytic reaction temperature is too high, so that the product decomposition is increased, the subsequent separation difficulty is increased, and further, the purity of the rectified diethyl methylphosphonite product is only 95 wt%, the yield of methyl aluminum chloride is only 82%, the yield of methyl phosphorus dichloride is only 80%, and the yield of diethyl methylphosphonite is only 79%.
It can be seen from the above examples and comparative examples that the present invention uses aluminum powder and chloromethane as raw materials and catalyst to perform gas-solid catalytic reaction in fluidized bed reactor and obtain methyl aluminum chloride by separation, which increases mass transfer process and improves reaction rate;
meanwhile, the method synthesizes the methyl phosphorus dichloride in the closed reaction kettle, which is beneficial to improving the simplicity and convenience of the synthesis operation of the methyl phosphorus dichloride;
the method can achieve high yield in a short time, so that the yield of the methyl aluminum chloride is 90-95%, the yield of the methyl phosphorus dichloride is 98%, and the yield of the methyl phosphite ester product is further improved to be more than 90%.
The applicant indicates that the present invention is illustrated in detail by the above examples, but the present invention is not limited to the above detailed application, that is, the present invention is not meant to be necessarily dependent on the above detailed method. It will be apparent to those skilled in the art that any modifications to the invention, equivalent alterations to the starting materials for the products of the invention, and additions of auxiliary components, specific operating conditions and modes of choice, etc., are deemed to be within the scope and disclosure of the invention.

Claims (91)

1. A system for preparing methyl phosphite ester is characterized by comprising a methyl aluminum chloride synthesis unit, a methyl phosphorus dichloride synthesis unit and a methyl phosphite ester synthesis unit; the methyl aluminum chloride synthesis unit comprises a fluidized bed reactor (1) and a separation unit which are sequentially connected, a gas distributor (5) is arranged above a gas material inlet at the bottom in the fluidized bed reactor (1), and the aperture opening rate of gas holes in the gas distributor (5) is 0.2-15%; the separation unit comprises a gas-solid separation device (2) and a gas treatment device which are connected in sequence, a material outlet of the fluidized bed reactor (1) is connected with a material inlet of the gas-solid separation device (2), a gas outlet of the gas-solid separation device (2) is connected with an inlet of the gas treatment device, and solid materials of the gas-solid separation device return to the fluidized bed reactor (1); the gas-solid separation device (2) is a cyclone separator;
the methyl phosphorus dichloride synthesis unit comprises a methyl phosphorus dichloride synthesis device (6), and the methyl phosphorus dichloride synthesis device (6) is a closed reaction kettle; the methyl aluminum chloride obtained by the methyl aluminum chloride synthesis unit enters a methyl phosphorus dichloride synthesis unit, and the methyl phosphorus dichloride obtained by the methyl phosphorus dichloride synthesis unit enters a methyl phosphite synthesis unit;
the methyl phosphorus dichloride synthesis unit also comprises a product separation device (7), and a material outlet of the methyl phosphorus dichloride synthesis device (6) is connected with a material inlet of the product separation device (7); the product separation device (7) is a distillation device with a vacuum system; the methyl phosphite ester synthesis unit comprises a methyl phosphite ester synthesis device (8), a byproduct removal device and a rectifying tower (10) which are sequentially connected, and the product methyl phosphorus dichloride obtained by the methyl phosphorus dichloride synthesis unit enters the methyl phosphite ester synthesis device (8) in the methyl phosphite ester synthesis unit for synthesis reaction; the methyl phosphite ester synthesis device (8) is any one or the combination of at least two of a reaction kettle, a tubular reactor or a packed tower; the de-byproduct device comprises a deacidification device (9); the deacidification device (9) is any one or the combination of at least two of a reaction kettle, a falling film evaporator or a tower reactor; the number of the rectifying towers (10) is at least one.
2. The system according to claim 1, characterized in that the fluidized bed reactor (1) is provided with a gas material inlet at the bottom and a solid material inlet at the side wall.
3. The system of claim 2, wherein the gas feed inlet is connected to a methyl chloride transfer line.
4. The system of claim 3, wherein the methyl chloride conveying line is provided with a heating device.
5. The system according to claim 1, wherein the aperture of the openings in the gas distributor (5) is 3mm to 8 mm.
6. The system according to claim 1, wherein the openings on the gas distributor (5) are circular, elliptical, triangular, square or regular polygonal openings.
7. The system according to claim 1, wherein the openings of the gas distributor (5) are distributed in a triangular, circular, square or diamond shape.
8. The system according to claim 1, characterized in that a heat exchanger is arranged in the fluidized bed reactor (1).
9. The system according to claim 8, wherein the heat exchanger is arranged above the gas distributor (5).
10. The system of claim 8, wherein the heat exchanger is any one of a U-tube heat exchanger, a finger-tube heat exchanger, or a serpentine heat exchanger, or a combination of at least two thereof.
11. The system according to claim 1, wherein the number of gas-solid separation devices (2) is more than or equal to 1.
12. The system according to claim 1, wherein the gas-solid separation device (2) is placed above the inside of the fluidized bed reactor (1) and/or outside the fluidized bed reactor (1).
13. The system according to claim 12, wherein when the number of gas-solid separation devices (2) is larger than or equal to 2, the first gas-solid separation device (2) is placed above the inside of the fluidized bed reactor (1) and/or outside the fluidized bed reactor (1).
14. The system according to claim 12, characterized in that when the gas-solid separation device (2) is placed inside the fluidized bed reactor (1), the solid material outlet of the gas-solid separation device (2) is communicated to the top of the gas distributor in the fluidized bed reactor (1) through a pipeline.
15. The system according to claim 12, wherein when the gas-solid separation device (2) is placed outside the fluidized bed reactor (1), the solid material outlet of the gas-solid separation device (2) is communicated from the outside and/or inside of the fluidized bed reactor (1) to above the gas distributor in the fluidized bed reactor (1) through a pipeline.
16. The system according to claim 1, characterized in that the gas treatment device comprises a degassing column (4).
17. The system according to claim 16, wherein a scrubber (3) is arranged in the gas treatment device before the degassing tower (4), and a gas outlet is arranged at the top of the scrubber (3) and connected with the degassing tower (4).
18. A system according to claim 17, characterized in that the bottom of the scrubber tower (3) is provided with a solid residue containing slurry discharge.
19. The system according to claim 17, characterized in that the scrubber (3) is externally provided with a condenser, a gas outlet at the top of the scrubber (3) is connected with an inlet of the condenser, a liquid outlet of the condenser is connected with a material reflux inlet at the top of the scrubber (3), and a gas outlet of the condenser is connected with a gas inlet of the degasser (4).
20. The system according to claim 17, characterized in that the scrubber (3) is provided with a first reboiler at the bottom.
21. The system according to claim 17, wherein the bottom of the washing column (3) is provided with a product outlet, the output material of the product outlet is divided into two paths, one path is returned to the washing column (3) through the first reboiler, and the other path is sent to the methyl phosphorus dichloride synthesis unit.
22. The system according to claim 16, characterized in that the degassing tower (4) is provided with a gas outlet which is connected to a methyl chloride transfer line.
23. The system according to claim 16, wherein the bottom of the degassing column (4) is provided with a second reboiler.
24. The system according to claim 16, wherein a product outlet is arranged at the bottom of the degassing tower (4), the output material of the product outlet is divided into two paths, one path is returned to the degassing tower (4) through the second reboiler, and the other path is sent to the methyl phosphorus dichloride synthesis unit.
25. The system according to claim 1, wherein the methyl phosphite synthesis unit (8) is provided with an alcohol inlet connected with an alcohol delivery line.
26. The system according to claim 1, wherein the material outlet of the methyl phosphite synthesis unit (8) is connected to the material inlet of the deacidification unit (9).
27. The system according to claim 1, wherein the product outlet of the de-coproduction device is connected to the feed inlet of the rectification column (10).
28. The system according to claim 1, characterized in that a condenser is arranged on the top of the rectifying tower (10).
29. The system according to claim 28, wherein the condensate of the condenser is divided into two paths, one path is returned to the rectifying tower (10), and the other path is connected with the storage tank.
30. The system according to claim 1, characterized in that the rectifying tower (10) is provided with a third reboiler at the bottom.
31. The system according to claim 30, wherein the output of the third reboiler is divided into two paths, one path returning to the rectification column (10) and one path connecting the storage tank.
32. The system of claim 1, wherein the system comprises a methyl aluminum chloride synthesis unit, a methyl phosphorus dichloride synthesis unit, and a methyl phosphite synthesis unit; the methyl aluminium chloride synthesis unit comprises a fluidized bed reactor (1) and a separation unit which are sequentially connected, the separation unit comprises a gas-solid separation device (2) and a gas treatment device which are sequentially connected, a material outlet at the top of the fluidized bed reactor (1) is connected with a material inlet of the gas-solid separation device (2), the methyl phosphorus dichloride synthesis unit comprises a methyl phosphorus dichloride synthesis device (6) and a product separation device (7) which are sequentially connected, and the methyl phosphorus dichloride synthesis device (6) is a closed reaction kettle; a product outlet of the gas treatment device in the separation unit is connected with a material inlet of the methyl phosphorus dichloride synthesis device (6), the methyl phosphite synthesis unit comprises a methyl phosphite synthesis device (8), a deacidification device (9) and a rectifying tower (10) which are sequentially connected, and a product outlet of the product separation device (7) in the methyl phosphorus dichloride synthesis unit is connected with a material inlet of the methyl phosphite synthesis device (8) in the methyl phosphite synthesis unit;
the bottom of the fluidized bed reactor (1) is provided with a gas material inlet, the side wall of the fluidized bed reactor is provided with a solid material inlet, the gas material inlet is connected with a chloromethane conveying pipeline, and heating equipment is arranged on the chloromethane conveying pipeline; a gas distributor (5) is arranged above a gas material inlet at the bottom in the fluidized bed reactor (1), the opening rate of gas holes on the gas distributor (5) is 0.2-15%, and the opening aperture is 3-8 mm; a heat exchanger is arranged in the fluidized bed reactor (1), the heat exchanger is arranged above the gas distributor, and the heat exchanger is any one or the combination of at least two of a U-shaped tube heat exchanger, a finger-shaped tube heat exchanger or a snake-shaped tube heat exchanger;
the gas outlet of the gas-solid separation device (2) is connected with the inlet of the gas treatment device, and the gas-solid separation device (2) is a cyclone separator; the gas-solid separation device (2) is arranged above the inside of the fluidized bed reactor (1) and/or outside the fluidized bed reactor (1), and a solid material outlet of the gas-solid separation device (2) is communicated to the upper part of a gas distributor in the fluidized bed reactor (1) from the outside and/or the inside of the fluidized bed reactor (1) through a pipeline;
the gas treatment device comprises a washing tower (3) and a degassing tower (4) which are connected in sequence; a condenser is arranged outside the washing tower (3), a gas outlet at the top of the washing tower (3) is connected with an inlet of the condenser, a liquid outlet of the condenser is connected with a material reflux port at the top of the washing tower (3), and a gas outlet of the condenser is connected with a gas inlet of the degassing tower (4); the bottom of the washing tower (3) is provided with a first reboiler; a product outlet is formed in the bottom of the washing tower (3), the material output from the product outlet is divided into two paths, one path of the material returns to the washing tower (3) through a first reboiler, and the other path of the material is sent to a methyl phosphorus dichloride synthesis unit; the degassing tower (4) is provided with a gas outlet, and the gas outlet is connected with a chloromethane conveying pipeline; a second reboiler and a product outlet are arranged at the bottom of the degassing tower (4), the material output from the product outlet is divided into two paths, one path is returned to the degassing tower (4) through the second reboiler, and the other path is sent to the methyl phosphorus dichloride synthesis unit;
the product separation device (7) is a distillation device with a vacuum system;
the methyl phosphite ester synthesis device (8) is any one or the combination of at least two of a reaction kettle, a tubular reactor or a packed tower; the methyl phosphite ester synthesis device (8) is provided with an alcohol inlet which is connected with an alcohol conveying pipeline; the deacidification device (9) is any one or the combination of at least two of a reaction kettle, a falling film evaporator or a tower reactor; a condenser is arranged at the top of the rectifying tower (10), condensate of the condenser is divided into two paths, one path returns to the rectifying tower (10), and the other path is connected with a storage tank; a third reboiler is arranged at the bottom of the rectifying tower (10); the discharge of the third reboiler is divided into two paths, one path is returned to the rectifying tower (10), and the other path is connected with the storage tank.
33. A process for the preparation of a methyl phosphite, wherein the process is carried out in the system of any one of claims 1-32, the process comprising the steps of:
(a) carrying out gas-solid catalytic reaction on raw material aluminum, a catalyst and gasified chloromethane in a fluidized bed reactor (1) to obtain mixed gas;
(b) separating the mixed gas obtained in the step (a) to obtain a methyl aluminum chloride product;
(c) reacting the methyl aluminum chloride product obtained in the step (b) with phosphorus trichloride in a methyl phosphorus dichloride synthesis device (6) to generate a ligand CH3PCl2·2AlCl3Then reacting with alkali metal halide to obtain methyl phosphorus dichloride;
(d) and (c) reacting the methyl phosphorus dichloride obtained in the step (c) with alcohol to obtain a methyl phosphite ester product.
34. The method of claim 33, wherein the raw material aluminum in step (a) is any one or a combination of at least two of solid particulate aluminum, aluminum powder or aluminum-magnesium alloy.
35. The method of claim 34, wherein the aluminum source of step (a) is aluminum powder.
36. The method of claim 35, wherein the aluminum powder has an average particle size of 5 mesh to 400 mesh.
37. The method of claim 36, wherein the aluminum powder has an average particle size of 20to 200 mesh.
38. The method of claim 33, wherein the catalyst in step (a) is any one of aluminum trichloride, aluminum trichloride complex, elemental halogen or hydrogen halide or a combination of at least two of the foregoing.
39. The method of claim 38, wherein the aluminum trichloride complex is a mixture of aluminum trichloride and methyl aluminum dichloride and/or dimethyl aluminum chloride.
40. The method of claim 39, wherein the mass ratio of the mixture of aluminum trichloride and methylaluminum dichloride and/or dimethylaluminum chloride is (100-1000): 1.
41. The method of claim 40, wherein the mass ratio of the mixture of aluminum trichloride and methylaluminum dichloride and/or dimethylaluminum chloride is (200-500): 1.
42. The method as claimed in claim 33, wherein the mass ratio of the raw material aluminum to the catalyst in the step (a) is (100-1000): 1.
43. The method as claimed in claim 42, wherein the mass ratio of the raw material aluminum to the catalyst in the step (a) is (200-500): 1.
44. The process according to claim 33, characterized in that the flow rate of the gasified methyl chloride of step (a) into the fluidized bed reactor (1) is between 0.2m/s and 40 m/s.
45. The process according to claim 44, characterized in that the flow rate of the gasified methyl chloride of step (a) into the fluidized bed reactor (1) is 0.2-10 m/s.
46. The process according to claim 33, characterized in that the methyl chloride gasified in step (a) is fed into the fluidized-bed reactor (1) via a gas distributor (6) for gas distribution.
47. The process of claim 33, wherein the reaction temperature of the gas-solid catalytic reaction in step (a) is 150 ℃ to 300 ℃.
48. The method as claimed in claim 47, wherein the reaction temperature of the gas-solid catalytic reaction in step (a) is 160-200 ℃.
49. The process according to claim 33, characterized in that the bed pressure drop in the fluidized bed reactor (1) in step (a) is between 1kPa and 50 kPa.
50. The process according to claim 49, characterized in that the bed pressure drop in the fluidized bed reactor (1) in step (a) is between 1kPa and 10 kPa.
51. The process of claim 33, wherein the gas-solid catalytic reaction of step (a) is carried out under a first protective atmosphere.
52. The method of claim 51 wherein the first protective atmosphere is any one of nitrogen, helium, neon, or argon, or a combination of at least two thereof.
53. The method of claim 52, wherein the first protective atmosphere is nitrogen.
54. The process of claim 33, wherein the separation treatment of step (b) comprises gas-solid separation, scrubbing and degassing.
55. The method of claim 54, wherein the gas-solid separation is a cyclonic separation process.
56. The method as claimed in claim 54, wherein the solid phase obtained by the gas-solid separation is raw material aluminum and catalyst, and the raw material aluminum and the catalyst are returned to the fluidized bed reactor (1) for gas-solid phase catalytic reaction.
57. The method as claimed in claim 54, wherein the gas after gas-solid separation is washed to obtain a product and a washed gas, and the washed gas is subjected to degassing treatment.
58. The process according to claim 57, wherein the degassing treatment results in methyl aluminum chloride and methyl chloride, which is returned to the fluidized bed reactor (1) for gas-solid phase catalytic reaction.
59. The method as claimed in claim 58, wherein the methyl chloride is returned to the fluidized-bed reactor (1) for gas-solid phase catalytic reaction after being compressed, condensed, gasified and heated.
60. The method of claim 33, wherein the separation process is performed under a second protective atmosphere.
61. The method of claim 60, wherein the second protective atmosphere is any one of nitrogen, helium, neon, or argon, or a combination of at least two thereof.
62. The method of claim 61, wherein the second protective atmosphere is nitrogen.
63. The process of claim 33, wherein the methyl aluminum chloride of step (b) is a mixture of methyl aluminum dichloride and dimethyl aluminum chloride.
64. The process of claim 33, wherein the reaction temperature of the methyl aluminum chloride product of step (c) with phosphorus trichloride is from-10 ℃ to 80 ℃.
65. The method of claim 33, wherein the alkali metal halide comprises any one of sodium chloride, potassium bromide, potassium iodide, or sodium bromide, or a combination of at least two thereof.
66. The method of claim 33, wherein the molar ratio of the methyl aluminum chloride product to the phosphorus trichloride in the step (c) is 1 (3-15).
67. The method of claim 33, wherein the molar ratio of the methyl aluminum chloride product to the alkali metal halide in the step (c) is 1 (2-20).
68. The method of claim 33, wherein 3CH is used in step (c)3PCl2·2AlCl3The reaction temperature of the reaction with the alkali metal halide is 50 ℃ to 220 ℃.
69. The method of claim 33, wherein 3CH is used in step (c)3PCl2·2AlCl3The reaction pressure for the reaction with the alkali metal halide is 2to 100 torr.
70. The process of claim 33, wherein the alcohol in step (d) is a liquid alcohol.
71. The process of claim 70, wherein in step (d) the alcohol is any one of methanol, ethanol, propanol, isopropanol, n-butanol or isobutanol, or a combination of at least two thereof.
72. The method as claimed in claim 33, wherein the molar ratio of the methyl phosphorus dichloride and the alcohol in the step (d) is 1 (0.5-10).
73. The method as claimed in claim 72, wherein the molar ratio of the methyl phosphorus dichloride and the alcohol in the step (d) is 1 (1-4).
74. The process of claim 33, wherein the alkyl group linked to the ester group in the methylphosphite in step (d) is a linear alkane having from about C1 to about C4 and/or a pendant alkane having from about C1 to about C4.
75. The method as claimed in claim 74, wherein the alkyl group linked to the ester group is any one or a combination of at least two of methyl, ethyl, propyl, isopropyl, n-butyl or isobutyl.
76. The method as claimed in claim 33, wherein when the methyl phosphite ester is methyl phosphite monoester, the molar ratio of the methyl phosphorus dichloride and the alcohol is 1 (1-1.2).
77. The method as claimed in claim 33, wherein when the product methyl phosphite ester is a methyl phosphite diester, the molar ratio of methyl phosphorus dichloride and alcohol is 1 (2-2.4).
78. The process of claim 33, wherein the reaction temperature of the reaction in step (d) is from 0 ℃ to 100 ℃.
79. The process of claim 78, wherein the reaction temperature of the reaction in step (d) is 10 ℃ to 40 ℃.
80. The process of claim 33, wherein the reaction pressure of the reaction in step (d) is from 0MPa to-0.1 MPa.
81. The process of claim 80, wherein the reaction pressure of the reaction in step (d) is from-0.05 MPa to-0.095 MPa.
82. The process of claim 33, wherein the reaction product of methyl phosphorus dichloride and alcohol in step (d) is sequentially deacidified and rectified to produce a methyl phosphite product.
83. A process as claimed in claim 82, wherein the deacidification temperature is in the range of from 0 ℃ to 100 ℃.
84. The method as recited in claim 83 wherein the temperature of de-acidification is from 40 ℃ to 80 ℃.
85. A process as claimed in claim 82, wherein the pressure of deacidification is in the range of from 0MPa to-0.1 MPa.
86. The method as recited in claim 85, wherein the pressure of said de-acidification is in the range of-0.05 MPa to-0.095 MPa.
87. The method as claimed in claim 82, wherein the temperature of the rectification is 0 ℃ to 180 ℃.
88. The method as claimed in claim 87, wherein the temperature of the rectification is 80-160 ℃.
89. The method as claimed in claim 82, wherein the pressure of the rectification is between 0MPa and-0.1 MPa.
90. The method as claimed in claim 89, wherein the pressure of the rectification is between-0.05 MPa and-0.095 MPa.
91. The method according to claim 33, characterized in that it comprises the steps of:
(a') carrying out gas-solid catalytic reaction on aluminum powder serving as a raw material, a catalyst and gasified chloromethane in a fluidized bed reactor (1), wherein the reaction temperature is 150-300 ℃, the pressure drop of a bed layer in the fluidized bed reactor (1) is 1-50 kPa, the gas-solid catalytic reaction is carried out in a first protective atmosphere to obtain a mixed gas, the catalyst is any one or the combination of at least two of aluminum trichloride, an aluminum trichloride compound, a halogen simple substance or hydrogen halide, the mass ratio of the aluminum serving as the raw material to the catalyst is (100-1000): 1, and the flow rate of the gasified chloromethane is 0.2-40 m/s;
(b ') carrying out gas-solid separation, washing and degassing treatment on the mixed gas obtained in the step (a') to obtain a methyl aluminum chloride product; wherein, the solid materials obtained by gas-solid separation are raw material aluminum and catalyst, the raw material aluminum and the catalyst return to the fluidized bed reactor (1) for gas-solid phase catalytic reaction, methyl aluminum chloride and methyl chloride are obtained by degassing treatment, and the methyl chloride returns to the fluidized bed reactor (1) for gas-solid phase catalytic reaction;
(c ') reacting the mixture of the methyl aluminium dichloride product obtained in the step (b') and dimethyl aluminium chloride with phosphorus trichloride in a methyl phosphorus dichloride synthesis device (6) to generate ligand 3CH3PCl2·2AlCl3Then reacting with alkali metal halide to obtain methyl phosphorus dichloride, wherein the methyl aluminum chloride product and phosphorus trichlorideThe molar ratio of the aluminum chloride is 1 (3-15), the molar ratio of the methyl aluminum chloride product to the alkali metal halide is 1 (2-20), and 3CH3PCl2·2AlCl3The reaction temperature of the reaction with the alkali metal halide is 50 ℃ to 220 ℃, and the reaction pressure is 2torr to 100 torr;
(d ') reacting the methyl phosphorus dichloride obtained in the step (c') with alcohol according to a molar ratio of 1 (0.5-10), wherein the reaction temperature is 10-40 ℃, the reaction pressure is-0.05 MPa-0.095 MPa, so as to obtain a reacted material, deacidifying the reacted material under the conditions that the temperature is 40-80 ℃, and the pressure is-0.05 MPa-0.095 MPa, so as to remove a byproduct hydrogen chloride, and rectifying the deacidified material under the conditions that the temperature is 80-160 ℃, and the pressure is-0.05 MPa-0.095 MPa, so as to obtain a methyl phosphite ester product.
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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB260647A (en) * 1925-06-04 1926-11-04 Birkett Wylam Improvements in and relating to dyes and dyeing
CN101337912A (en) * 2008-08-29 2009-01-07 江苏安邦电化有限公司 Method for preparing 3-iodo-2-propynyI butyl carbamate
CN105669748A (en) * 2016-02-22 2016-06-15 四川省乐山市福华通达农药科技有限公司 Synthesis method of methyl phosphorus dichloride
CN105907430A (en) * 2016-06-21 2016-08-31 东南大学 Device for producing synthesis gas through biomass gasification and method of device

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB260647A (en) * 1925-06-04 1926-11-04 Birkett Wylam Improvements in and relating to dyes and dyeing
CN101337912A (en) * 2008-08-29 2009-01-07 江苏安邦电化有限公司 Method for preparing 3-iodo-2-propynyI butyl carbamate
CN105669748A (en) * 2016-02-22 2016-06-15 四川省乐山市福华通达农药科技有限公司 Synthesis method of methyl phosphorus dichloride
CN105907430A (en) * 2016-06-21 2016-08-31 东南大学 Device for producing synthesis gas through biomass gasification and method of device

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
O,O-二乙基甲基亚膦酸酯的合成及应用研究;王宇光;《浙江工业大学硕士学位论文》;20041231;第2-3章 *

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