CN113666805A - Method and production system for continuously producing 4-chloro-3, 5-dimethylphenol - Google Patents
Method and production system for continuously producing 4-chloro-3, 5-dimethylphenol Download PDFInfo
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- CN113666805A CN113666805A CN202110968844.5A CN202110968844A CN113666805A CN 113666805 A CN113666805 A CN 113666805A CN 202110968844 A CN202110968844 A CN 202110968844A CN 113666805 A CN113666805 A CN 113666805A
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- C07—ORGANIC CHEMISTRY
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- C07C37/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring
- C07C37/62—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring by introduction of halogen; by substitution of halogen atoms by other halogen atoms
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C37/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring
- C07C37/68—Purification; separation; Use of additives, e.g. for stabilisation
- C07C37/685—Processes comprising at least two steps in series
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C37/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring
- C07C37/68—Purification; separation; Use of additives, e.g. for stabilisation
- C07C37/70—Purification; separation; Use of additives, e.g. for stabilisation by physical treatment
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
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- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/52—Improvements relating to the production of bulk chemicals using catalysts, e.g. selective catalysts
Abstract
The invention relates to a method and a production system for continuously producing 4-chloro-3, 5-dimethylphenol, comprising the following steps: continuously introducing a reaction material containing 3, 5-dimethylphenol (MX), a chlorinating agent and a solvent into a reactor for reaction to obtain a first mixture containing 4-chloro-3, 5-dimethylphenol (PCMX), MX and the solvent, wherein at least part of the PCMX is in a crystalline state; continuously introducing the solvent and the first mixture into a washing device, and separating to obtain a second mixture containing MX and the solvent and a third mixture containing the solvent and PCMX in a crystalline state; continuously introducing part or all of the second mixture into the reactor; and continuously outputting the third mixture out of the washing equipment, and treating to obtain PCMX. The invention can greatly reduce the phenomenon that the crystal wraps 3, 5-dimethylphenol by continuously separating out the PCMX in a crystalline state generated in the reaction process, thereby not only improving the conversion rate, but also ensuring that the reaction can be carried out at low temperature all the time, and finally obtaining higher selectivity and conversion rate of the target product.
Description
Technical Field
The invention belongs to the technical field of organic chemical synthesis, and particularly relates to a method and a production system for continuously producing 4-chloro-3, 5-dimethylphenol.
Background
4-chloro-3, 5-dimethylphenol (parachlorometaxylenol, PCMX for short) is a high-efficiency broad-spectrum mildew-proof antibacterial agent and is widely applied in the fields of daily use, medical use, industrial sterilization and the like. 4-chloro-3, 5-dimethylphenol is gaining increasing attention to personal hygiene and is coming to the larger market.
4-chloro-3, 5-dimethylphenol is generally obtained by industrially carrying out chlorination reaction on 3, 5-dimethylphenol/1-hydroxy-3, 5-dimethylbenzene serving as a raw material under the action of a chlorinating agent, wherein the chlorinating agent can be sulfuryl chloride or chlorine, and the specific process mainly comprises the following steps:
1) the reaction is carried out in the absence of an organic solvent, for example, Chinese patent CN102199075A mentions that 4-chloro-3, 5-dimethylphenol is obtained by reacting 1-hydroxy-3, 5-dimethylbenzene, an oxidizing agent and a chlorine-containing inorganic substance in the absence of an organic solvent by using a cupric salt as a catalyst, but the whole reaction process only depends on adding a small amount of water or water contained in the reaction raw materials and water which is generated in the reaction and is equimolar with the product as a solvent to assist stirring. In practical implementation results, the method does not use an organic solvent, is beneficial to environmental protection, but is difficult to uniformly disperse in the whole reaction system, is not beneficial to proton transmission, and is difficult to control the reaction progress and the reaction selectivity.
2) The reaction is carried out at a high temperature, for example, in Chinese patent CN 103351282A, 3, 5-dimethyl-4-chlorophenol is synthesized by taking cupric salt as a catalyst, 3, 5-dimethylphenol (MX for short) as a raw material, oxygen as an oxidant and hydrochloric acid as a chlorinating agent through the reaction at a temperature of 90-98 ℃. When the actual MX conversion rate reaches 99%, the product selectivity only reaches 80%, the product selectivity is low, and the product separation difficulty is increased; chinese patent CN102675055B introduces a new process for producing parachloro-m-cresol by a high-temperature chlorination method, wherein preheated raw materials and a chlorinating agent are subjected to up-down convection reaction at a reaction temperature of 110-130 ℃, although a continuous reaction process is realized, actually, due to higher reaction temperature, the selectivity of byproducts can be greatly increased, in addition, due to forced external circulation, the material composition in the whole tower is the same, when the conversion rate of the raw materials is higher, the product concentration in the tower is higher, and after the parachloro-m-cresol is contacted with the chlorinating agent, the yield of target products is further reduced.
3) The reaction is carried out under the condition of multi-stage temperature control, for example, patent CN104326881A discloses a method for synthesizing 4-chloro-3, 5-dimethylphenol by performing directional chlorination reaction at two stages of low-temperature chlorination and high-temperature chlorination by using 3, 5-dimethylphenol as a raw material, tetrachloroethylene as a solvent, benzylthiophenol and aluminum chloride as a co-catalyst, and sulfuryl chloride as a chlorinating agent. The method utilizes low-temperature chlorination to maintain the selectivity of the product 4-chloro-3, 5-dimethylphenol, and high-temperature chlorination to improve the conversion rate of a substrate, thereby achieving the purpose of improving the product yield. However, in the high-temperature chlorination stage, the selectivity of the product is reduced, and the catalyst of the method is difficult to recover and has serious environmental pollution; in patent CN101823941B, a green industrial preparation method of 4-chloro-3, 5-dimethylphenol is provided, in which water is used as a solvent, sulfuryl chloride or chlorine is used as a chlorinating agent, and a substrate, 3, 5-dimethylphenol, is subjected to chlorination reaction in a multi-stage temperature control manner. The method has the advantages of complicated operation, low continuous degree and difficult industrial large-scale application, and the problem of processing the 4-chloro-3, 5-dimethylphenol aqueous phase is not mentioned.
4) The reaction is carried out at a low temperature, for example, patent CN102659528A describes a process for continuously producing PCMX in a form of three reaction kettles connected in series, and a continuous reaction process with a high conversion rate is realized by controlling the reaction at a low temperature of 25-35 ℃, and by continuously overflowing the reaction solution, on one hand, the use of a plurality of reactors can increase the investment cost and the process risk, and on the other hand, because the reaction temperature is low, the solubility of the product in the solvent is reduced, so that a large amount of solvent is inevitably used to maintain the reaction material as a homogeneous solution, the reaction conversion rate is 90-100%, the selectivity is about 80%, and although a continuous process is realized, the product selectivity is still low.
The above synthesis method has problems of low selectivity of the target product or low conversion rate of the raw material.
In order to improve the selectivity of the target product and the conversion rate of the raw material, a method for producing 4-chloro-3, 5-dimethylphenol by using a reaction rectifying tower and a rectifying tower with specific structures is proposed, for example, a reaction rectifying device and a method for producing 4-chloro-3, 5-dimethylphenol disclosed in patent CN111574329A, wherein the reaction rectifying device comprises a reaction rectifying tower, a first condenser, a first reboiler, a rectifying tower, a second condenser, a third condenser, a second reboiler and a vacuum system which are connected with each other through pipelines, and the method comprises the following steps: using sulfuryl chloride and 3, 5-dimethylphenol as raw materials, and continuously adding the sulfuryl chloride to the upper part of a reaction rectifying section of a reaction rectifying tower; continuously adding 3, 5-dimethylphenol into the lower part of a reaction rectifying section of a reaction rectifying tower, condensing the tower top of the reaction rectifying tower to obtain sulfur dioxide and hydrogen chloride gas, and refluxing a solvent and a small amount of reaction raw material sulfuryl chloride to the tower top of the reaction rectifying tower and the bottom of the reaction rectifying section; the bottom of the reaction rectifying tower contains a crude product of a reaction product 4-chloro-3, 5-dimethylphenol, and the crude product enters a rectifying and refining tower to be separated to obtain a 4-chloro-3, 5-dimethylphenol product. Compared with other methods, the method can realize continuous production, and the selectivity and yield of the target product are high. However, the method needs a reaction rectifying tower and a rectifying and refining tower with specific structures, and the equipment investment cost is greatly increased. Meanwhile, the temperature and the system pressure of each section in the reaction rectifying tower and the rectifying tower are strictly controlled in the production process, the feeding temperature of the raw material 3, 5-dimethylphenol is required to be increased to 70-80 ℃, the operation is complex, the energy consumption is increased, and the cost is further increased.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide a method for continuously producing 4-chloro-3, 5-dimethylphenol with high selectivity, high yield and low cost.
In order to achieve the purpose, the technical scheme is as follows:
a method for continuously producing 4-chloro-3, 5-dimethylphenol using a reaction mass comprising 3, 5-dimethylphenol, a chlorinating agent, and a solvent, the method comprising:
continuously introducing the reaction materials into a reactor, and reacting the reaction materials in the reactor to obtain a first mixture containing 4-chloro-3, 5-dimethylphenol, 3, 5-dimethylphenol and a solvent, wherein at least part of the 4-chloro-3, 5-dimethylphenol in the first mixture is in a crystalline state;
continuously introducing a solvent and the first mixture into a washing device, and separating to obtain a second mixture containing 3, 5-dimethylphenol and the solvent and a third mixture containing the solvent and crystalline 4-chloro-3, 5-dimethylphenol;
continuously passing a portion or all of the second mixture into the reactor;
and continuously outputting the third mixture out of the washing equipment, and carrying out aftertreatment to obtain the 4-chloro-3, 5-dimethylphenol.
According to the invention, the first mixture and the third mixture are both crystal mush. The second mixture is in a liquid state.
According to the invention, the 3, 5-dimethylphenol and the chlorinating agent in the reactor are respectively in a liquid state and/or a dissolved state.
Further, the temperature of the materials in the reactor is controlled to be 20-40 ℃. Preferably, the temperature of the materials in the reactor is controlled to be 25-35 ℃.
Further, when the crystalline state of 4-chloro-3, 5-dimethylphenol appears in the reactor, a material containing the crystalline state of 4-chloro-3, 5-dimethylphenol in the reactor is continuously passed into the washing device.
In some embodiments, the post-treatment results in a purity of greater than or equal to 99.0% for 4-chloro-3, 5-dimethylphenol.
According to some embodiments of the invention, the method further comprises sampling the third mixture to detect the purity of 4-chloro-3, 5-dimethylphenol, and when the purity detected by sampling is lower than a set purity, heating the third mixture output from the washing equipment and then returning the heated third mixture to the washing equipment; and when the purity of the sampling detection is higher than the set purity, carrying out post-treatment on the third mixture to obtain the crystals of the 4-chloro-3, 5-dimethylphenol. Preferably, the set purity is 99.0%.
Preferably, the heating temperature for heating the third mixture is 50 to 60 ℃.
In some preferred and specific embodiments, the post-treatment is selected from one of the following modes a, b:
the method a: carrying out reduced pressure distillation on the third mixture through a distillation tower, recovering a solvent at the top of the distillation tower, cooling, crystallizing and drying a material at the bottom of the distillation tower to obtain a 4-chloro-3, 5-dimethylphenol product;
mode b: and carrying out centrifugal separation on the third mixture to obtain crystalline 4-chloro-3, 5-dimethylphenol and a liquid material, carrying out reduced pressure distillation on the liquid material through a distillation tower, recovering a solvent at the top of the tower, cooling and crystallizing the material at the bottom of the tower, mixing the material with the crystalline 4-chloro-3, 5-dimethylphenol, and drying to obtain a 4-chloro-3, 5-dimethylphenol product.
Preferably, in the mode a, the temperature of the top of the distillation tower is controlled to be 70-100 ℃, and the pressure is controlled to be-0.1-0.06 MPa; preferably, the temperature of the top of the distillation tower is controlled to be 75-90 ℃ and the pressure is controlled to be-0.1-0.08 MPa.
Preferably, in the mode a or the mode b, in the drying process, the temperature is controlled to be 60-100 ℃, the pressure is controlled to be-0.1-0.02 MPa, and the time is 60-500 min; preferably, the temperature is controlled to be 60-80 ℃, the pressure is-0.08-0.05 MPa, and the time is 60-200 min.
According to some embodiments of the invention, when the total mass content of 2, 4-dichloro-3, 5-dimethylphenol and 2-chloro-3, 5-dimethylphenol in the second mixture is below a set content, passing the entire second mixture into the reactor; when the total mass content of the 2, 4-dichloro-3, 5-dimethylphenol and the 2-chloro-3, 5-dimethylphenol in the second mixture exceeds a set content, introducing a portion of the second mixture into the reactor.
In some preferred and specific embodiments, when the total mass content of 2, 4-dichloro-3, 5-dimethylphenol and 2-chloro-3, 5-dimethylphenol in the second mixture exceeds a set content, less than 90% of the second mixture is passed into the reactor. Preferably, when the total mass content of the 2, 4-dichloro-3, 5-dimethylphenol and the 2-chloro-3, 5-dimethylphenol exceeds a set content, 80 to 90 percent of the second mixture is introduced into the reactor.
In some preferred and specific embodiments the method further comprises the step of detecting the total mass content of 2, 4-dichloro-3, 5-dimethylphenol and 2-chloro-3, 5-dimethylphenol in the second mixture; and/or, when the total mass content of the 2, 4-dichloro-3, 5-dimethylphenol and the 2-chloro-3, 5-dimethylphenol in the second mixture exceeds a set content, using the remaining part of the second mixture for preparing the 2, 4-dichloro-3, 5-dimethylphenol.
In some embodiments, the means for detecting may be an online real-time detection of the total mass content of 2, 4-dichloro-3, 5-dimethylphenol and 2-chloro-3, 5-dimethylphenol in the second mixture to monitor the total mass content of 2, 4-dichloro-3, 5-dimethylphenol and 2-chloro-3, 5-dimethylphenol in the second mixture in real-time to control the amount of the second mixture entering the reactor. Or intermittently sampling to detect the total mass content of the 2, 4-dichloro-3, 5-dimethylphenol and the 2-chloro-3, 5-dimethylphenol in the second mixture.
In some preferred and specific embodiments, the set content is between 10wt% and 20 wt%. Preferably, the set content is 15%.
In the actual production process, when the set content is more than 15%, continuously introducing 80-90% of the second mixture into the reactor, continuously extracting the rest part of the second mixture for preparing 2, 4-dichloro-3, 5-dimethylphenol, gradually reducing the total mass content of the 2, 4-dichloro-3, 5-dimethylphenol and the 2-chloro-3, 5-dimethylphenol in the second mixture along with the continuous production process, and temporarily closing an extracted pipeline when the total mass content is reduced to below 15% or even lower. And after the produced pipeline is closed, along with the production, the total mass content of the 2, 4-dichloro-3, 5-dimethylphenol and the 2-chloro-3, 5-dimethylphenol in the second mixture is increased, and the produced pipeline is opened, and the operation is circulated. By intermittently or continuously extracting a part of the second mixture to be used for producing other substances so as to control the byproducts of the whole system, and extracting the second mixture to be used for producing other substances (such as 2, 4-dichloro-3, 5-dimethylphenol), the three-waste treatment amount is greatly reduced, and great help is brought to the improvement of the liquid supply environment.
In the present invention, the solvent does not participate in the calculation when calculating the total mass content of the 2, 4-dichloro-3, 5-dimethylphenol and the 2-chloro-3, 5-dimethylphenol.
Further, the feeding mass ratio of the 3, 5-dimethylphenol to the chlorinating agent is 1: 1-2; and/or the feeding mass ratio of the 3, 5-dimethylphenol to the solvent is 1: 1-10.
Further, the chlorinating agent is one or more of hydrochloric acid, hypochlorous acid, sodium chloride, potassium chloride, chlorine and sulfuryl chloride. Preferably, the chlorinating agent is one or a combination of hydrochloric acid, chlorine gas and sulfuryl chloride. Further preferably, the feeding mass ratio of the 3, 5-dimethylphenol to the sulfuryl chloride is 1: 1.1-1.5.
In the present invention, when the chlorinating agent is selected from hydrochloric acid, hypochlorous acid, sodium chloride and potassium chloride, an oxidizing agent and a catalyst are also added into the reactor.
Further, the solvent is one or more of dichloroethane, chloroform, chlorobenzene, dichlorobenzene, trichlorotoluene, trichloroethylene and tetrachloroethylene. Preferably, the solvent is one or more of dichloroethane, chlorobenzene and tetrachloroethylene. Further preferably, in the reaction materials, the feeding mass ratio of the 3, 5-dimethylphenol to the tetrachloroethylene is 1: 1-5.
In some embodiments, the feed flow rates of the 3, 5-dimethylphenol, the solvent and the chlorinating agent in the reaction mass are respectively 0.2-1.5 m3/h、0.6～3.0m3/h、0.12～1.7m3H is used as the reference value. Preferably, the feeding flow rates of the 3, 5-dimethylphenol, the solvent and the chlorinating agent are respectively 0.2-1 m3/h、0.6～2.0m3/h、0.2～0.5m3H is used as the reference value. More preferably, the feeding flow rates of the 3, 5-dimethyl phenol, the solvent and the chlorinating agent are respectively 0.2-0.8 m3/h、0.6～1.0m3/h、0.2～0.5m3/h。
In some embodiments, the first mixture has a flow rate of 1 to 15m3H is used as the reference value. Preferably, the flow rate of the first mixture is 1-10 m3H is used as the reference value. Further preferably, the flow rate of the first mixture is 3-5 m3/h。
In some embodiments, the solvent is fed into the washing device at a feed rate of 0.5 to 10m3H is used as the reference value. Further preferably, the input flow of the solvent is 0.5-5 m3H is used as the reference value. Even more preferably, the input flow rate of the solvent is 0.5-1.5 m3/h。
According to the invention, the solvent used in the reaction mass is the same solvent as the solvent fed into the washing apparatus. As in some embodiments, the solvents are all tetrachloroethylene.
In some embodiments, the second mixture is mixed at a flow rate of 1 to 15m3H is fed into the reactor. The preferred flow rate is 2-10 m3A more preferable flow rate is 2 to 5m3/h。
In some embodiments, the third mixture is mixed at a flow rate of 0.5 to 5m3And outputting the result of the reaction per hour. Further preferably, the third mixture is mixed at a flow rate of 1-3 m3And outputting the result of the reaction per hour.
In some preferred and specific embodiments, the washing apparatus includes a housing, a filter screen disposed in the housing for solid-liquid separation, and a first inlet, a second inlet, a first outlet, and a second outlet disposed on the housing, wherein the first outlet and the second outlet are respectively disposed at two opposite sides of the filter screen, the first inlet and the second inlet are both disposed at one side of the filter screen where the first outlet is disposed, the first inlet is communicated with the reactor through a pipeline and is used for introducing the first mixture into the housing, the second inlet is used for introducing a solvent, the first outlet is used for outputting the third mixture, and the second outlet is used for outputting the second mixture.
Preferably, the casing is vertical, first export, second export are located respectively the bottom and the top of casing, the height of first entry and second entry is less than the filter screen is high just first entry and second entry are located respectively the relative both sides of casing, the second entry is less than first entry setting. Further preferably, the first inlet is located 1/4-2/3 above the height of the enclosure and the second inlet is located 1/4-1/2 above the height of the enclosure. Still further preferably, the first inlet is located 1/3-1/2 of the housing height and the second inlet is located 1/4-1/3 of the housing height.
Further, the bottom of the shell is also provided with a stirring mechanism, so that the third mixture in a crystal slurry state can be conveniently output to the washing equipment.
Further, the filter screen is in can be in along upper and lower direction in the casing slides, washing equipment still include with the filter screen links to each other and is used for the drive the filter screen is in gliding connecting rod in the casing, through the drive the connecting rod and then the drive the filter screen is in slide from top to bottom in the casing, be convenient for in the debugging process, confirm the filter screen optimum position prevents that the crystal from following the second mixture gets into the reactor.
Preferably, the shell is further provided with a third outlet, the third outlet and the second outlet are both positioned on the same side of the filter screen, the second outlet is communicated with the reactor through a pipeline, and the third outlet is used for connecting the reactor and external equipment except the washing equipment.
Preferably, the mesh opening of the filter screen is 20-50 meshes.
According to some embodiments of the invention, the method further comprises connecting the reactor to a heat exchanger to form an external recycle loop to control the temperature of the material in the reactor.
According to some embodiments of the invention, the method further comprises a step of returning a liquid part of the gas volatilized from the reactor after condensation to the reactor and extracting a gas part of the gas.
The second technical scheme adopted by the invention is as follows: a production system for continuously producing 4-chloro-3, 5-dimethylphenol comprises a reactor and a washing device communicated with the reactor through a pipeline, wherein the reactor is provided with a feed inlet for feeding reaction materials comprising 3, 5-dimethylphenol, a chlorinating agent and a solvent into the reactor, the reaction materials react in the reactor to obtain a first mixture comprising the 4-chloro-3, 5-dimethylphenol, the 3, 5-dimethylphenol and the solvent, at least part of the 4-chloro-3, 5-dimethylphenol in the first mixture is in a crystalline state, the washing device comprises a shell and a filter screen arranged in the shell, the shell is provided with a first inlet, a second inlet, a first outlet and a second outlet, the first inlet is communicated with the reactor through a first pipeline and is used for introducing the first mixture into the shell, the second inlet is used for introducing a solvent into the shell and mixing the solvent with the first mixture, the solvent and the first mixture are mixed and then subjected to solid-liquid separation through the filter screen to obtain a second mixture containing 3, 5-dimethylphenol and the solvent and a third mixture containing the solvent and crystalline 4-chloro-3, 5-dimethylphenol, the first outlet is used for outputting the third mixture, and a second pipeline is arranged between the second outlet and the reactor and is used for inputting part or all of the second mixture into the reactor.
In some embodiments, the casing is vertical to be set up, first export, second export are located respectively the bottom and the top of casing, the height that highly is less than of first entry and second entry the filter screen place height just first entry and second entry are located respectively the relative both sides of casing, the casing bottom still sets up rabbling mechanism, the filter screen is in along upper and lower direction in the casing can slide in the casing, washing equipment still include with the filter screen links to each other and is used for the drive the filter screen is in the gliding connecting rod of casing.
In some embodiments, a third pipeline for conveying the third mixture is connected to the first outlet, the production system further comprises a condenser communicated with the top of the reactor through a fourth pipeline and a fifth pipeline respectively, a first heat exchanger connected with the reactor through a sixth pipeline and a seventh pipeline respectively, a second heat exchanger connected with the washing equipment through an eighth pipeline and a ninth pipeline respectively, and a tenth pipeline for conveying a solvent is connected to the second inlet.
The third technical scheme adopted by the invention is as follows: a method for continuously producing 4-chloro-3, 5-dimethylphenol by using the production system, wherein the reaction materials comprise 3, 5-dimethylphenol, a solvent and a chlorinating agent, and the method comprises the following steps:
s1: respectively at a flow rate of 0.2-1.5 m3/h、0.6～3.0m3/h、0.12～1.7m3H continuously reacting the 3, 5-dimethylphenol, the solvent and the chlorinating agentIntroducing the mixture into the reactor through the feed inlet, and reacting in the reactor to obtain the first mixture;
s2: continuously feeding the first mixture at a flow rate of 1-15 m3H, conveying the solvent into the washing equipment through the first pipeline, and simultaneously continuously conveying the solvent through the second inlet at a flow rate of 0.5-10 m3H, introducing the mixture into the washing equipment to mix with the first mixture and washing the crystalline 4-chloro-3, 5-dimethylphenol to obtain a second mixture and a third mixture;
s3: continuously passing the third mixture through the first outlet at a flow rate of 0.5-5 m3The washing equipment is output, and simultaneously, part or all of the second mixture is continuously mixed at a flow rate of 1-15 m3H is conveyed into the reactor through the second pipeline;
s4: sampling and detecting the purity of the 4-chloro-3, 5-dimethylphenol aiming at the third mixture, and when the purity detected by sampling is lower than the set purity, heating the third mixture output from the washing equipment and then returning the third mixture to the washing equipment; and when the purity detected by sampling is higher than the set purity, carrying out post-treatment on the third mixture, and recovering the solvent in the third mixture to obtain the crystals of the 4-chloro-3, 5-dimethylphenol.
In some embodiments, the step S2 is started after the step S1 is performed for 3 to 5 hours.
In the actual continuous production process, the feed flow rates of the 3, 5-dimethylphenol, the solvent and the chlorinating agent, the flow rate of the first mixture entering the washing equipment, the flow rate of the second mixture conveyed into the reactor and the output flow rate of the third mixture are not certain values, and all of the feed flow rates, the flow rates and the output flow rates can be adjusted within a certain range, the adjustment of the flow rates is specifically adjusted according to the liquid level condition of the materials in the reactor, specifically according to the size of the reactor and the specific liquid level of the materials in the reactor, for example, the liquid level of the materials in a certain reactor is controlled to be 1.2 meters in the actual production process, if the liquid level is higher than 1.2 meters, the flow rate of the materials entering the washing equipment can be increased, or the flow rates of the 3, 5-dimethylphenol, the solvent and the chlorinating agent can be reduced, or reducing the flow rate of the second mixture that flows back into the reactor; otherwise, if the liquid level is lower than 1.2 m, the reverse operation is carried out according to the operation.
Due to the application of the technical scheme, compared with the prior art, the invention has the following advantages:
the method of the invention continuously separates the crystalline 4-chloro-3, 5-dimethylphenol generated in the reaction process by simple separation and washes the 4-chloro-3, 5-dimethylphenol by a solvent, thereby greatly reducing the phenomenon that the 3, 5-dimethylphenol is wrapped by crystals, not only improving the conversion rate, but also ensuring that the reaction can be carried out at low temperature, finally obtaining higher selectivity and conversion rate of the target product, wherein the selectivity reaches more than 91 percent, the conversion rate reaches more than 97 percent, and the yield of the target product is high.
The method of the invention mainly uses a reactor and washing equipment in combination, compared with the existing method which uses a reaction rectifying tower and a rectification rectifying tower in combination, special equipment is not needed, the investment cost and the energy consumption of production equipment are greatly reduced, and the separated crude product can be obtained into a target product only through simple post-treatment, thereby further reducing the cost and being suitable for large-scale continuous chemical industry production.
Drawings
FIG. 1 is a schematic diagram of a production system for preparing 4-chloro-3, 5-dimethylphenol according to an embodiment of the present invention;
in the figure, 1, a reactor; 2. washing equipment; 2a, a shell; 2b, a filter screen; 2c, a first inlet; 2d, a second inlet; 2e, a first outlet; 2f, a second outlet; 2g and a third outlet; 2h, a third inlet; 2i, a connecting rod; 2j, a stirring mechanism; 3. a first heat exchanger; 4. a condenser; 5. a first delivery pump; 6. a second delivery pump; 7. a second heat exchanger;
a. a first conduit; b. a second conduit; c. a third pipeline; d. a fourth conduit; e. a fifth pipeline; f. a sixth pipeline; g. A seventh pipe; h. an eighth conduit; i. a ninth conduit; j. a tenth conduit; k. an eleventh conduit.
Detailed Description
The invention separates the 4-chloro-3, 5-dimethylphenol in a crystalline state generated by the reaction from the 3, 5-dimethylphenol continuously, greatly reduces the phenomenon that the 3, 5-dimethylphenol is wrapped by the crystal, improves the conversion rate, ensures that the reaction can be carried out at low temperature all the time, and finally obtains higher selectivity and conversion rate of the target product.
One preferred and specific embodiment is as follows:
the adopted reaction materials comprise 3, 5-dimethylphenol, a chlorinating agent and a solvent, the method comprises the steps of continuously introducing the reaction materials into a reactor, and reacting the reaction materials in the reactor to obtain a first mixture containing 4-chloro-3, 5-dimethylphenol, 3, 5-dimethylphenol and the solvent, wherein at least part of 4-chloro-3, 5-dimethylphenol in the first mixture is in a crystalline state, the reactor adopts a jacketed reactor, a cooling medium is introduced into a jacket to control the temperature of the materials in the reactor to be 20-40 ℃, and further, the forced external circulation of the materials in the reactor is realized through a heat exchanger externally connected with the reactor to further ensure that the materials in the reactor are controlled at a low temperature;
continuously introducing a solvent and the first mixture in the reactor into a washing device, washing the crystalline 4-chloro-3, 5-dimethylphenol in the first mixture by the solvent, and then separating to obtain a second mixture containing the 3, 5-dimethylphenol and the solvent and a third mixture containing the solvent and the crystalline 4-chloro-3, 5-dimethylphenol;
when the second mixture is sampled and detected that the total mass content of the 2, 4-dichloro-3, 5-dimethylphenol and the 2-chloro-3, 5-dimethylphenol is below a set content (preferably the set content is 15 percent), introducing the whole second mixture into the reactor; when the total mass content of the 2, 4-dichloro-3, 5-dimethylphenol and the 2-chloro-3, 5-dimethylphenol in the second mixture exceeds a set content, introducing 80-90% of the second mixture into a reactor, and outputting the rest part for preparing the 2, 4-dichloro-3, 5-dimethylphenol;
sampling the third mixture to detect the purity of the 4-chloro-3, 5-dimethylphenol, and when the purity of the sampling detection is lower than the set purity (such as 99.0 percent), heating the third mixture output from the washing equipment and then returning the third mixture to the washing equipment; and when the purity detected by sampling is higher than the set purity, carrying out post-treatment on the third mixture, and recovering the solvent in the third mixture to obtain crystals of the 4-chloro-3, 5-dimethylphenol.
As shown in FIG. 1, the process of the present invention can be carried out in a continuous production system as shown in the figure.
As shown in FIG. 1, a continuous production system for 4-chloro-3, 5-dimethylphenol comprises a reactor 1 and a washing apparatus 2 connected to the reactor 1 via a pipe.
The reactor 1 is provided with a feed inlet for introducing a reaction material into the reactor 1 and reacting in the reactor 1 to generate 4-chloro-3, 5-dimethylphenol, wherein the reaction material contains 3, 5-dimethylphenol, a solvent and a chlorinating agent, the feed inlet is provided with two feed inlets, the two feed inlets are respectively connected with a feed pipe, one feed pipe is respectively connected with a raw material pipe of the 3, 5-dimethylphenol and a raw material pipe of the solvent, and the other feed pipe is connected with a raw material pipe of the chlorinating agent.
The washing device 2 comprises a vertically arranged shell 2a, a filter screen 2b which is arranged in the shell 2a in a sliding way along the up-down direction of the shell 2a and is used for solid-liquid separation, a connecting rod 2i of which the lower end part is connected with the filter screen 2b and the upper end part extends out of the shell 2a, and a stirring mechanism 2j arranged at the bottom of the shell 2a, wherein the shell 2a is provided with a first inlet 2c, a second inlet 2d, a third inlet 2h, a first outlet 2e, a second outlet 2f and a third outlet 2g, the first outlet 2e and the second outlet 2f are respectively arranged at the bottom and the top of the shell 2a and are respectively arranged at two opposite sides of the filter screen 2b, the first inlet 2c and the second inlet 2d are respectively arranged at one side of the filter screen 2b, which is provided with the first outlet 2e, the first inlet 2c and the second inlet 2d are respectively arranged at two opposite sides of the shell 2a, the first inlet 2c, the second inlet 2c, The height of second entry 2d all is less than the height that filter screen 2b belongs to and second entry 2d is less than first entry 2c setting, and third export 2g all is located the upside of filter screen 2b with second export 2f, and third entry 2h is located casing 2a bottom.
The first inlet 2c is communicated with the bottom of the reactor 1 through a first pipeline a and is used for introducing a first mixture into the washing device 2, the first pipeline a is provided with a first delivery pump 5, the second inlet 2d is used for introducing a washing solvent into the washing device 2, the first outlet 2e is used for outputting a third mixture obtained after solid-liquid separation, the second pipeline b is further connected between the second outlet 2f and the top of the reactor 1 and is used for inputting a second mixture obtained after solid-liquid separation into the reactor 1, and the third outlet 2g is used for connecting external equipment except the reactor 1 and the washing device 2.
In this example, a third pipe c for discharging the third mixture is connected to the first outlet 2e, and a second transfer pump 6 is provided in the third pipe c.
The production system also comprises a condenser 4 connected with the top of the reactor 1 through a fourth pipeline d and a fifth pipeline e, gas in the reactor 1 enters the condenser 4 through the fourth pipeline d for condensation, liquid obtained by condensation flows back to the reactor 1 through the fifth pipeline e, and tail gas obtained by collection and condensation is used for synthesizing high value-added products (such as trimethyl orthoacetate, triethyl orthoacetate, sulfuryl chloride and the like) after separation and purification.
The production system further comprises a first heat exchanger 3, a heat medium channel of the first heat exchanger 3 is connected with the reactor 1 through a sixth pipeline f and a seventh pipeline g respectively, and a refrigerant is introduced into a refrigerant channel of the first heat exchanger 3 for heat exchange so as to control the materials in the reactor 1 to be kept at 20-40 ℃. In this example, the sixth pipeline f is connected to the first pipeline a, and the connection between the sixth pipeline f and the first pipeline a is located between the first delivery pump 5 and the first inlet 2 c; the seventh pipe g is connected to the second pipe b.
The production system also comprises a second heat exchanger 7, a refrigerant channel of the second heat exchanger 7 is respectively connected with the washing equipment 2 through an eighth pipeline h and a ninth pipeline i, and heat medium is introduced into a heat medium channel of the second heat exchanger 7 for heat exchange. In this example, the eighth pipeline h is connected to the third pipeline c, the ninth pipeline i is connected to the third inlet 2h at the bottom of the washing device 2, and the second heat exchanger 7 is used for heating the crude product with unqualified purity, and then reflowing to the washing device 2 for washing again.
In this example, a tenth pipe j for transporting the washing solvent is connected to the second inlet 2d, and an eleventh pipe k for connecting to an external device is connected to the third outlet 2 g.
In some embodiments, the volume of the reactor 1 may be 1 to 10m3The heat exchange area of the first heat exchanger 3 is 2-20 m2Preferably, the volume of the reactor 1 may be 3 to 8m3The heat exchange area of the first heat exchanger 3 is 5-15 m2。
In some embodiments, the washing apparatus 2 has a height h of 100 to 300cm and a diameter D of 10 to 100 cm. Preferably, the height h is 100-200 cm, and the diameter D is 20-50 cm.
The technical solutions of the present invention are described in detail below with reference to specific examples so that those skilled in the art can better understand and implement the technical solutions of the present invention, but the present invention is not limited to the scope of the examples.
Example 1
In this embodiment, the production system shown in fig. 1 is used to continuously produce 4-chloro-3, 5-dimethylphenol, and specifically comprises the following steps:
(1) tetrachloroethylene, 3, 5-dimethylphenol and sulfuryl chloride are respectively added at a ratio of 0.8m3/h、0.5m3/h、0.35m3The flow of the reaction solution is continuously added into the reactor 1 through a feeding hole, a first conveying pump 5 is started to force external circulation, and the temperature of materials in the reactor 1 is controlled to be 25-35 ℃;
(2) after feeding for 3 hours, communicating the reactor 1 with the washing equipment 2 through a first pipeline a, and controlling the material flow of the material in the reactor 1 entering the washing equipment 2 through the first pipeline a to be 4m3H, the flow rate of the washing solvent through the tenth pipe j is 1.0m3H, the flow rate of the second mixture through the second pipeline b is 3m3H, the flow rate of the third mixture through the third pipeline c is 2m3And h, the third mixture output by the third pipeline c is a crude product, the crude product is subjected to reduced pressure distillation, separation and recovery of a solvent in the mixture to obtain crystals, and the crystals are dried to obtain a pure 4-chloro-3, 5-dimethylphenol product.
In the continuous production process of this example, the mass of 3, 5-dimethylphenol and 4-chloro-3, 5-dimethylphenol in the system and the mass of the finished product 4-chloro-3, 5-dimethylphenol were sampled and measured at 4h, 6h and 8h, respectively, the conversion of 3, 5-dimethylphenol and the yield of 4-chloro-3, 5-dimethylphenol were calculated for each reaction period, and the selectivity of 4-chloro-3, 5-dimethylphenol was finally calculated, with the results shown in table 1.
Example 2
The process for producing 4-chloro-3, 5-dimethylphenol of this example was substantially the same as in example 1, except that:
in the step (1), the flow rates of tetrachloroethylene, 3, 5-dimethylphenol and sulfuryl chloride are respectively 3m3/h、1.2m3/h、0.9m3/h。
In the step (2), the flow of the materials in the reactor 1 through the first pipeline a is 5m3H, the flow rate of the washing solvent through the tenth pipe j is 10m3H, a second mixture comprising 3, 5-dimethylphenol and solvent flows through the second line b at a rate of 10m3H, a third mixture comprising 4-chloro-3, 5-dimethylphenol in crystalline form and solvent, via a third line c, at an output flow rate of 5m3/h。
Example 3
The process for producing 4-chloro-3, 5-dimethylphenol of this example was substantially the same as in example 1, except that:
respectively sampling and measuring the total mass content of 2, 4-dichloro-3, 5-dimethylphenol and 2-chloro-3, 5-dimethylphenol in the material in the second pipeline b when the materials react for 4 hours, 6 hours and 8 hours, and opening the eleventh pipeline k and controlling the flow of the eleventh pipeline k to be 0.5m when the content exceeds 15 percent when the materials react for 6 hours3The material discharged via the eleventh line k is used for the production of 2, 4-dichloro-3, 5-dimethylphenol. When the reaction time is 8h, the content is lower than 15 percent, and the eleventh pipeline k is closed.
Example 4
The process for producing 4-chloro-3, 5-dimethylphenol of this example was substantially the same as in example 1, except that:
after the reaction is carried out for 3 hours by sampling and measuring, the purity of the 4-chloro-3, 5-dimethylphenol in the material in the third pipeline c is lower than 99.0 percent, the material in the third pipeline c is heated by a second heat exchanger 7 and then conveyed back to the washing equipment 2, and the flow rates of the second pipeline b and the first pipeline a are correspondingly adjusted. After sampling and measuring for 4h, the purity is over 99.0 percent, and the material in the third pipeline c is output to the washing equipment 2.
Comparative example 1
61g of 3, 5-dimethylphenol and 305g of tetrachloroethylene are added into a 500ml four-neck flask, then a stirring device is started, the temperature is kept between 25 ℃ and 35 ℃, 67.1g of sulfuryl chloride is dropwise added at constant speed at the temperature for 8 hours, after the dropwise addition is finished, sampling and analysis are carried out, and the analysis results are shown in Table 1.
Comparative example 2
61g of 3, 5-dimethylphenol and 305g of tetrachloroethylene are added into a 500ml four-neck flask, then a stirring device is started, and 33.6g of sulfuryl chloride is dropwise added at a constant speed at 25-35 ℃ for 4 hours. Then, the reaction temperature is raised to 60-65 ℃, 16.8g of sulfuryl chloride is dropwise added at the temperature at a constant speed for 2 hours. And finally, raising the reaction temperature to 80-85 ℃, and continuously dropwise adding 16.8g of sulfuryl chloride at a constant speed for 2 hours. After the addition, samples were taken for analysis, and the analysis results are shown in Table 1.
Table 1 summarizes the results of the analyses of the products prepared in examples 1-4 and comparative examples 1-2
Note: the reaction time means several hours, examples 1 to 4 are continuous reactions, and the conversion, selectivity and yield are respectively the conversion, selectivity and yield of several hours in the table; comparative examples 1 and 2 are both batch reactions, and the conversion, selectivity and yield in the table are conversion, selectivity and yield after completion of the dropwise addition, respectively.
As can be seen from table 1, the present invention has the advantages of high conversion rate of raw materials and high yield of products, high economic efficiency, and long continuous production time, and is more conducive to obtaining excellent conversion rate of raw materials and high yield of products when 4-chloro-3, 5-dimethylphenol is continuously produced in representative examples.
The above embodiments are merely illustrative of the technical ideas and features of the present invention, and the purpose thereof is to enable those skilled in the art to understand the contents of the present invention and implement the present invention, and not to limit the protection scope of the present invention. All equivalent changes and modifications made according to the spirit of the present invention should be covered within the protection scope of the present invention.
The endpoints of the ranges and any values disclosed herein are not limited to the precise range or value, and such ranges or values should be understood to encompass values close to those ranges or values. For ranges of values, between the endpoints of each of the ranges and the individual points, and between the individual points may be combined with each other to give one or more new ranges of values, and these ranges of values should be considered as specifically disclosed herein.
Claims (16)
1. A method for continuously producing 4-chloro-3, 5-dimethylphenol by using a reaction mass comprising 3, 5-dimethylphenol, a chlorinating agent and a solvent, characterized in that the method comprises:
continuously introducing the reaction materials into a reactor, and reacting the reaction materials in the reactor to obtain a first mixture containing 4-chloro-3, 5-dimethylphenol, 3, 5-dimethylphenol and a solvent, wherein at least part of the 4-chloro-3, 5-dimethylphenol in the first mixture is in a crystalline state;
continuously introducing a solvent and the first mixture into a washing device, and separating to obtain a second mixture containing 3, 5-dimethylphenol and the solvent and a third mixture containing the solvent and crystalline 4-chloro-3, 5-dimethylphenol;
continuously passing a portion or all of the second mixture into the reactor;
and continuously outputting the third mixture out of the washing equipment, and carrying out aftertreatment to obtain the 4-chloro-3, 5-dimethylphenol.
2. The method for continuously producing the 4-chloro-3, 5-dimethylphenol according to claim 1, wherein the temperature of the materials in the reactor is controlled to be 20-40 ℃; and/or, when the crystalline state of the 4-chloro-3, 5-dimethylphenol appears in the reactor, continuously introducing the material containing the crystalline 4-chloro-3, 5-dimethylphenol in the reactor into the washing equipment.
3. The method for continuously producing 4-chloro-3, 5-dimethylphenol according to claim 1, further comprising sampling the third mixture to detect the purity of 4-chloro-3, 5-dimethylphenol, and when the purity detected by sampling is lower than a set purity, heating the third mixture output from the washing equipment and then feeding the heated third mixture back to the washing equipment; and when the purity of the sampling detection is higher than the set purity, carrying out post-treatment on the third mixture to obtain the crystals of the 4-chloro-3, 5-dimethylphenol.
4. The continuous production method of 4-chloro-3, 5-dimethylphenol according to claim 3, characterized in that the set purity is 99.0%.
5. The method for continuously producing 4-chloro-3, 5-dimethylphenol according to claim 1, wherein the post-treatment comprises subjecting the third mixture to reduced pressure distillation in a distillation tower, recovering the solvent at the top of the tower, cooling, crystallizing and drying the material at the bottom of the tower to obtain the 4-chloro-3, 5-dimethylphenol product.
6. The method for continuously producing 4-chloro-3, 5-dimethylphenol according to claim 1, characterized in that the purity of the 4-chloro-3, 5-dimethylphenol obtained by the work-up is 99.0% or more.
7. The continuous production method of 4-chloro-3, 5-dimethylphenol according to claim 1, characterized in that when the total mass content of the 2, 4-dichloro-3, 5-dimethylphenol and the 2-chloro-3, 5-dimethylphenol in the second mixture is below a set content, the entire second mixture is passed into the reactor; when the total mass content of the 2, 4-dichloro-3, 5-dimethylphenol and the 2-chloro-3, 5-dimethylphenol in the second mixture exceeds a set content, introducing less than 90% of the second mixture into the reactor, and using the rest part of the second mixture for further separation to obtain the by-product 2, 4-dichloro-3, 5-dimethylphenol.
8. The continuous production method of 4-chloro-3, 5-dimethylphenol according to claim 7, characterized by further comprising a step of detecting the total mass content of 2, 4-dichloro-3, 5-dimethylphenol and 2-chloro-3, 5-dimethylphenol in the second mixture; and/or the set content is between 10wt% and 20 wt%; and/or when the total mass content of the 2, 4-dichloro-3, 5-dimethylphenol and the 2-chloro-3, 5-dimethylphenol exceeds a set content, introducing 80-90% of a second mixture into the reactor.
9. The continuous production method of 4-chloro-3, 5-dimethylphenol according to any one of claims 1 to 3, it is characterized in that the washing equipment comprises a shell, a filter screen which is arranged in the shell and used for solid-liquid separation, a first inlet, a second inlet, a first outlet and a second outlet which are arranged on the shell, the first outlet and the second outlet are respectively positioned at two opposite sides of the filter screen, the first inlet and the second inlet are both positioned at one side of the filter screen, which is provided with the first outlet, and the first inlet is communicated with the reactor through a pipeline and is used for introducing the first mixture into the shell, the second inlet is used for introducing a solvent, the first outlet is used for outputting the third mixture, and the second outlet is used for outputting the second mixture.
10. The method for continuously producing 4-chloro-3, 5-dimethylphenol according to claim 9, wherein the housing is vertically arranged, the first outlet and the second outlet are respectively located at the bottom and the top of the housing, the first inlet and the second inlet are lower than the filter screen and are respectively located at the two opposite sides of the housing, the bottom of the housing is further provided with a stirring mechanism, the filter screen can slide in the housing along the up-down direction, and the washing device further comprises a connecting rod connected with the filter screen and used for driving the filter screen to slide in the housing.
11. The continuous process for preparing 4-chloro-3, 5-dimethylphenol according to claim 10, wherein the housing further comprises a third outlet on the same side of the screen as the second outlet, wherein the second outlet is in communication with the reactor via a conduit and the third outlet is used for connecting to external equipment other than the reactor and the washing equipment.
12. The method for continuously producing 4-chloro-3, 5-dimethylphenol according to any one of claims 1 to 8, characterized in that the feed flow rates of the 3, 5-dimethylphenol, the solvent and the chlorinating agent in the reaction mass are respectively 0.2 to 1.5m3/h、0.6~3.0m3/h、0.12~1.7m3H; and/or the feeding flow of the solvent introduced into the washing equipment is 0.5-10 m3H; and/or the flow rate of the first mixture entering the washing equipment is 1-15 m3H; and/or the second mixture is mixed at a flow rate of 1-15 m3H is conveyed into the reactor; and/or the flow of the third mixture output from the washing equipment is 0.5-5 m3/h。
13. The method for continuously producing the 4-chloro-3, 5-dimethylphenol according to any one of claims 1 to 8, characterized in that the feed mass ratio of the 3, 5-dimethylphenol to the chlorinating agent in the reaction mass is 1:1 to 2; and/or in the reaction material, the feeding mass ratio of the 3, 5-dimethylphenol to the solvent is 1: 1-10; and/or the chlorinating agent is one or the combination of more of hydrochloric acid, hypochlorous acid, sodium chloride, potassium chloride, chlorine and sulfuryl chloride; and/or the solvent is one or more of dichloroethane, chloroform, chlorobenzene, dichlorobenzene, trichlorotoluene, trichloroethylene and tetrachloroethylene.
14. The continuous production method of 4-chloro-3, 5-dimethylphenol according to any one of claims 1 to 8, characterized by further comprising connecting the reactor with a heat exchanger to form an external circulation loop to control the temperature of the material in the reactor.
15. A production system for continuously producing 4-chloro-3, 5-dimethylphenol, characterized in that the production system comprises a reactor and a washing device communicated with the reactor through a pipeline, the reactor is provided with a feed inlet for feeding reaction materials comprising 3, 5-dimethylphenol, a chlorinating agent and a solvent into the reactor, the reaction materials react in the reactor to obtain a first mixture comprising 4-chloro-3, 5-dimethylphenol, 3, 5-dimethylphenol and the solvent, and the 4-chloro-3, 5-dimethylphenol in the first mixture is at least partially in a crystalline state, the washing device comprises a shell and a filter screen arranged in the shell, and the shell is provided with a first inlet, a second inlet, a third inlet and a fourth inlet, The device comprises a first outlet and a second outlet, wherein the first inlet is communicated with the reactor through a first pipeline and is used for introducing the first mixture into the shell, the second inlet is used for introducing a solvent into the shell and mixing the solvent with the first mixture, the solvent and the first mixture are mixed and then subjected to solid-liquid separation through the filter screen to obtain a second mixture containing 3, 5-dimethylphenol and the solvent and a third mixture containing the solvent and crystalline 4-chloro-3, 5-dimethylphenol, the first outlet is used for outputting the third mixture, and a second pipeline is arranged between the second outlet and the reactor and is used for inputting part or all of the second mixture into the reactor.
16. The production system of claim 15, wherein the housing is vertically arranged, the first outlet and the second outlet are respectively located at the bottom and the top of the housing, the first inlet and the second inlet are lower than the filter screen and are respectively located at two opposite sides of the housing, the bottom of the housing is further provided with a stirring mechanism, the filter screen is slidable in the housing along the vertical direction, and the washing device further comprises a connecting rod connected with the filter screen and used for driving the filter screen to slide in the housing;
and/or the first outlet is connected with a third pipeline for conveying the third mixture, the production system further comprises a condenser communicated with the top of the reactor through a fourth pipeline and a fifth pipeline, a first heat exchanger connected with the reactor through a sixth pipeline and a seventh pipeline, a second heat exchanger connected with the washing equipment through an eighth pipeline and a ninth pipeline, and a tenth pipeline for conveying the solvent is connected to the second inlet.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102659528A (en) * | 2012-04-01 | 2012-09-12 | 江苏焕鑫高新材料科技有限公司 | Continuous kettle type chlorination technology |
| CN104326881A (en) * | 2014-10-16 | 2015-02-04 | 荣成青木高新材料有限公司 | Preparation method of 3,5-dimethyl-4-chlorophenol |
| CN111574329A (en) * | 2020-05-18 | 2020-08-25 | 万华化学集团股份有限公司 | Reactive distillation device and method for producing 4-chloro-3, 5-dimethylphenol |
| CN112169381A (en) * | 2020-10-15 | 2021-01-05 | 圣奥化学科技有限公司 | Solid-liquid separation washing device and application thereof |
-
2021
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102659528A (en) * | 2012-04-01 | 2012-09-12 | 江苏焕鑫高新材料科技有限公司 | Continuous kettle type chlorination technology |
| CN104326881A (en) * | 2014-10-16 | 2015-02-04 | 荣成青木高新材料有限公司 | Preparation method of 3,5-dimethyl-4-chlorophenol |
| CN111574329A (en) * | 2020-05-18 | 2020-08-25 | 万华化学集团股份有限公司 | Reactive distillation device and method for producing 4-chloro-3, 5-dimethylphenol |
| CN112169381A (en) * | 2020-10-15 | 2021-01-05 | 圣奥化学科技有限公司 | Solid-liquid separation washing device and application thereof |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2023284525A1 (en) * | 2021-07-13 | 2023-01-19 | 山东新和成维生素有限公司 | Method for preparing 4-chloro-3,5-dimethylphenol by means of low-temperature chlorination |
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