CN110078600B - Reactive distillation process device and method for synthesizing polymethoxy dimethyl ether - Google Patents

Reactive distillation process device and method for synthesizing polymethoxy dimethyl ether Download PDF

Info

Publication number
CN110078600B
CN110078600B CN201910307875.9A CN201910307875A CN110078600B CN 110078600 B CN110078600 B CN 110078600B CN 201910307875 A CN201910307875 A CN 201910307875A CN 110078600 B CN110078600 B CN 110078600B
Authority
CN
China
Prior art keywords
tower
formaldehyde
reaction
dimethyl ether
methylal
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201910307875.9A
Other languages
Chinese (zh)
Other versions
CN110078600A (en
Inventor
高鑫
孟莹
李洪
李鑫钢
从海峰
韩振为
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Tianjin University
Original Assignee
Tianjin University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Tianjin University filed Critical Tianjin University
Priority to CN201910307875.9A priority Critical patent/CN110078600B/en
Publication of CN110078600A publication Critical patent/CN110078600A/en
Application granted granted Critical
Publication of CN110078600B publication Critical patent/CN110078600B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C41/00—Preparation of ethers; Preparation of compounds having groups, groups or groups
    • C07C41/48—Preparation of compounds having groups
    • C07C41/50—Preparation of compounds having groups by reactions producing groups
    • C07C41/56—Preparation of compounds having groups by reactions producing groups by condensation of aldehydes, paraformaldehyde, or ketones
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C41/00—Preparation of ethers; Preparation of compounds having groups, groups or groups
    • C07C41/48—Preparation of compounds having groups
    • C07C41/58—Separation; Purification; Stabilisation; Use of additives
    • 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
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P20/00—Technologies relating to chemical industry
    • Y02P20/10—Process efficiency

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Abstract

The invention provides a reactive distillation process device and a method for synthesizing polymethoxy dimethyl ether, wherein the process method takes industrial methylal with end capped product chains and one or more than two mixtures of trioxymethylene, paraformaldehyde and gas-phase formaldehyde with increased product chains as raw materials, no water exists in a reaction system, polymethoxy dimethyl ether mixed products with multiple polymerization degrees are obtained by reaction under the action of an acid catalyst, the reaction products with the polymerization degree being more than 2 are obtained by the separation action of a polymethoxy dimethyl ether reactive distillation tower, DMM2 with low polymerization degree and unreacted complete methylal are obtained at the top of the tower; separating the tower bottom extract by a product refining tower to obtain a target product DMM3-5, and returning the DMM2 with low polymerization degree and the DMM6-10 with excessive polymerization degree to the polymethoxy dimethyl ether reaction rectifying tower; unreacted complete methylal is used as a raw material for recycling. The invention utilizes the characteristic of reactive distillation, and the reaction process uses excessive methylal to greatly improve the conversion rate of formaldehyde substances and the selectivity and the yield of DMM 3-5.

Description

Reactive distillation process device and method for synthesizing polymethoxy dimethyl ether
Technical Field
The invention belongs to the technical field of chemical production processes and equipment, and relates to polymethoxy dimethyl ether, which is a reactive distillation process device and a reactive distillation method for synthesizing polymethoxy dimethyl ether.
Background
The polymethoxy dimethyl ether is a low molecular weight acetal polymer taking methoxy as a main chain, and has the structural formula: CH3O (CH 2O) nCH3, abbreviated DMMn (or PODEn). When n=3-8 (especially 3-5), the material has higher cetane number and oxygen content, and no sulfur element exists in the material, so that the material is a diesel oxygen increasing agent with excellent performance, can greatly reduce the emission of carbon monoxide and oxynitride in the tail gas of a diesel vehicle, and does not generate sulfide. Meanwhile, the addition of the substance can improve the combustion performance of the diesel without modifying the vehicle engine, and has high popularization value.
The synthetic raw materials of DMMn mainly comprise methylal, methanol, dimethyl ether, formaldehyde solution, trioxymethylene and paraformaldehyde. The reaction of methylal and trioxymethylene, paraformaldehyde or gaseous formaldehyde has no water introduced into the system, so that the separation difficulty caused by water can be reduced, the product quality can be improved, and the method has great advantages in the operation cost. Such as: according to the method for preparing the polymethoxy dimethyl ether by the fixed bed reaction rectification disclosed by the patent CN104355973B, methylal and trioxymethylene are used as reactants, secondary serial reactions are carried out in a fixed bed reactor and a reaction rectifying tower, then multi-step separation is carried out, and the method for producing the polymethoxy dimethyl ether disclosed by the patent CN104974025A uses methylal and the trioxymethylene as the reactants, the reaction is carried out in a fluidized bed reactor, and then three serial units of rectification, extractive rectification and vacuum rectification are used for separating the reactants and reaction products, wherein methylal is used as the reactants in the polymerization reactor, the reactants are limited by chemical equilibrium, higher conversion rate cannot be achieved, most of the reaction products are DMM2, the selectivity and the yield of target products DMM 3-5 are lower, the circulating material quantity in the process is large, and the defects of large energy consumption and low process economy are brought; while patent CN104722249a proposes a method for obtaining polymethoxy dimethyl ether by two-part reaction of methylal and gaseous formaldehyde through a packed reaction tower and a multi-stage reaction tower, the method uses a reactive distillation tower to perform the second-step reaction, but the introduction of methanol in the reactive distillation tower can reduce the conversion rate of the reaction and the yield of the target product, and the flow circulation amount between the three towers is larger, which results in larger flow energy consumption. Patent CN108484371a proposes a process for preparing polymethoxy dimethyl ether by a tube-in-tube type floating bed reactor; germany Jakob Burgera et al propose a reaction-then-separation process in which the composition of DMM 3-5 after reaction is 33.43%. However, the existing anhydrous trioxymethylene preparation needs to be prepared through the technological processes of extraction, multi-step rectification and the like, the manufacturing cost is high, the market price of the anhydrous trioxymethylene is high, the economy of the polymethoxy dimethyl ether preparation process is limited, the reaction in the reactor is still limited by the reaction balance, the reaction conversion rate and the selectivity of target products are still low, the circulation flow is large, and the process economy needs to be further improved.
Disclosure of Invention
Aiming at the problems and defects, the invention aims to provide a reactive distillation process device and a reactive distillation process method for synthesizing polymethoxy dimethyl ether, and the process method using the reactive distillation as a core is used for preparing high-purity DMM 3-5, which has the advantages of high reactive conversion rate, effective control of reaction temperature, shortened reaction residence time, reduced circulating flow strand quantity, improved yield and selectivity of target products DMM 3-5, excessive methylal in the reaction process, high reactive conversion rate of chain growth reactants, reduced separation complexity caused by formaldehyde in the subsequent separation process, simple process flow, lower equipment investment, convenient operation, stable product quality, lower energy consumption and the like.
The first technical scheme of the invention is as follows:
the invention relates to a reactive distillation process device for synthesizing polymethoxy dimethyl ether, which comprises a polymethoxy dimethyl ether reactive distillation tower, a primary product refining tower, a secondary product refining tower, a light component separation tower, a methylal mixer and a DMM2 mixer, and is characterized in that:
the top of the polymethoxy dimethyl ether reaction rectifying tower is provided with a complete condenser, the tower kettle is provided with a reboiler, the polymethoxy dimethyl ether reaction rectifying tower is provided with a raw material feed inlet, a DMM 6-10 recovery feed inlet and a DMM2 recovery feed inlet, the tower kettle is provided with a liquid phase extraction outlet, the tower top is provided with either complete reflux or liquid phase extraction outlets, wherein the number of the raw material feed inlets is two, and the two raw material feed inlets are respectively connected with a chain growth raw material feed pipeline and a methylal mixer outlet pipeline.
The primary product refining tower and the secondary product refining tower are respectively provided with a full condenser at the top of the tower, a reboiler at the bottom of the tower, a liquid phase feed inlet is arranged on the tower body, liquid phase extraction ports are arranged at the top of the tower and the bottom of the tower, wherein the raw material feed inlet of the primary product refining tower is connected with the liquid phase extraction port at the bottom of the polymethoxy dimethyl ether reaction rectifying tower through a pipeline, and the top extraction port is connected with a feed pipeline of a DMM2 mixer; the raw material feed inlet of the secondary product refining tower is connected with the liquid phase extraction outlet at the bottom of the primary product refining tower through a pipeline, the liquid phase extraction outlet at the bottom of the secondary product refining tower is connected with the DMM 6-10 recovery feed inlet through a pipeline, and the liquid phase extraction outlet at the top of the secondary product refining tower is connected with the target product extraction pipeline.
The light component separation tower, the tower top are provided with a complete condenser, the tower bottom is provided with a reboiler, the tower top and the tower bottom are both provided with liquid phase extraction ports, the light component separation tower is provided with a feed inlet and is connected with the tower top extraction port of the polymethoxy dimethyl ether reaction rectifying tower, the tower bottom extraction port is connected with a feed pipeline of a DMM2 mixer, the tower top extraction port is connected with the feed inlet of the methylal mixer, the equipment is used for selecting whether the polymethoxy dimethyl ether reaction rectifying tower exists or not according to the characteristics of a reaction system and a catalyst, and if the polymethoxy dimethyl ether reaction rectifying tower does not exist, the polymethoxy dimethyl ether reaction rectifying tower is in complete reflux operation.
The polymethoxy dimethyl ether reaction rectifying tower consists of a rectifying section, a reaction section and a stripping section, or consists of a reaction section and a rectifying section; the rectifying section and the stripping section tower internals are fillers or trays; the reaction section is filled with acidic solid catalyst, and the tower internal part is catalytic packing type or catalytic tower plate type.
Two liquid phase reactant feed inlets and two circulating material feed inlets are arranged on the reaction section of the polymethoxy dimethyl ether reaction rectifying tower; or a liquid phase reactant feed inlet and two circulating material feed inlets are arranged on the reaction section of the polymethoxy dimethyl ether reaction rectifying tower, and a gas phase reactant feed inlet is arranged on the reaction section or stripping section.
The two product refining towers and one light component separating tower are stuffing and tray.
The reactive distillation process method for synthesizing the polymethoxy dimethyl ether comprises the following steps:
step 1, respectively feeding methylal for providing product chain end capping and trioxymethylene for providing product chain growth, paraformaldehyde or a mixture of substances from a methylal mixer and a chain growth reactant feeding pipeline through two liquid-phase feeding ports on a reaction section of a polymethoxy dimethyl ether reaction rectifying tower, or respectively feeding methylal and gaseous formaldehyde from a raw material liquid-phase feeding port and a gaseous-phase feeding port on the polymethoxy dimethyl ether reaction rectifying tower for reaction;
Step 2, separating a reaction zone from a high boiling point product DMM 3-10 (containing trace DMM 2) generated by the reaction through a stripping section of a polymethoxy dimethyl ether reaction rectifying tower, extracting liquid phase from a tower bottom of the polymethoxy dimethyl ether reaction rectifying tower, separating a reaction zone from a low polymerization degree product DMM2 generated by the reaction and unreacted methylal through a rectifying section of the polymethoxy dimethyl ether reaction rectifying tower, and extracting liquid phase pipelines from the top of the polymethoxy dimethyl ether reaction rectifying tower;
step 3, conveying a liquid phase extracted from the tower bottom of the polymethoxy dimethyl ether reaction rectifying tower to a primary product refining tower and a secondary product refining tower for refining products, conveying DMM2 separated from the tower top of the primary product refining tower to a DMM2 mixer, and extracting high-purity target products DMM 3-5 separated from the tower top of the secondary product refining tower from a tower top liquid phase extraction pipeline; the product DMM 6-10 with the excessively high polymerization degree is separated from the tower kettle, is extracted from a liquid phase output pipeline of the tower kettle and is conveyed to a circulating material feed inlet of the polymethoxy dimethyl ether reaction rectifying tower;
and step 4, carrying out total reflux operation on the tower top of the polymethoxy dimethyl ether reaction rectifying tower, returning to the tower top of the polymethoxy dimethyl ether reaction rectifying tower, or carrying out liquid phase extraction at a certain reflux ratio, then conveying to a light component separating tower for light component separation, separating a low-polymerization-degree product DMM2 from the tower bottom of the light component separating tower, mixing the low-polymerization-degree product DMM2 with the DMM2 separated from the tower top of the primary product refining tower through a mixer, returning to a reaction zone of the polymethoxy dimethyl ether reaction rectifying tower for secondary reaction, and mixing methylal extracted from the tower top with methylal raw materials in the methylal and the mixer, and then entering the polymethoxy dimethyl ether reaction rectifying tower for reaction.
In the step 1, the preferable mass ratio of polyoxymethylene or paraformaldehyde or gaseous formaldehyde to methylal serving as a raw material of the polymethoxy dimethyl ether reactive rectifying tower is 0.6-4.5.
In the step 2, the working pressure of the polymethoxy dimethyl ether reaction rectifying tower is preferably 2-7atm, the preferred range of the reflux ratio of the tower top is 0.1-5 or total reflux, the catalyst adopts an acidic solid catalyst, preferably an acidic resin catalyst or an acidic molecular sieve catalyst, the preferred range of the use amount is 20-300kg/m < 3 >, the internal parts of the polymethoxy dimethyl ether reaction rectifying tower reaction section are catalytic packing or catalytic trays, the catalytic packing height is 2-5 m, and the catalytic trays are 8-35; the rectifying section and stripping section tower internals are packing or trays, the height of the packing of the rectifying section is 1-5 m, the height of the trays is 5-30, the height of the packing of the stripping section is 0.5-4 m, and the height of the trays is 3-25.
In the step 3, the tower top operation pressure of the primary product refining tower is preferably in the range of 0.5-1.5atm, the tower top reflux ratio is preferably in the range of 0.1-5, tower internals are packing or trays, the packing height is 1-5 m, and the trays are 10-45 blocks; the preferred range of the operation pressure at the top of the secondary product refining tower is 0.5-1.5atm, the preferred range of the reflux ratio at the top of the tower is 0.2-3, the tower internals are packing or trays, the height of the packing is 1-5 m, and the trays are 10-45 blocks.
In the step 4, the preferable range of the top operating pressure of the light component separation tower is 0.5-1.8atm, the preferable range of the top reflux ratio is 0.1-3, the tower internals are packing or trays, the packing height is 1-5 m, and the trays are 8-45 blocks.
The second technical scheme of the invention:
the raw materials which are limited to enter the reactive distillation column of the polymethoxy dimethyl ether are anhydrous methylal and anhydrous trioxymethylene.
The process method comprises a formaldehyde preparation section, a formaldehyde polymerization section, a methylal preparation section and a polymethoxy dimethyl ether reaction rectification preparation section. Raw material methanol is subjected to oxidation reaction, absorption and other processes in a formaldehyde preparation section to obtain formaldehyde aqueous solution, part of the product is subjected to reaction separation-separation process in a formaldehyde polymerization section to obtain anhydrous trioxymethylene, the other part of the product is subjected to reaction with methanol in a methylal preparation section to obtain anhydrous methylal, and methylal and trioxymethylene enter a polymethoxy dimethyl ether reaction rectification preparation section to obtain a high-purity target product DMM3-5 through the reaction separation-separation process.
The formaldehyde preparation section comprises a methanol evaporator, a gas mixer, a preheater, an oxidation reactor and a water absorption tower. Raw material industrial methanol is gasified into methanol gas by a methanol evaporator and then enters a gas mixer to be mixed with oxygen; the mixed gas is preheated to the reaction temperature by a preheater and then enters an oxidation reactor for methanol oxidation reaction to obtain formaldehyde gas; the formaldehyde gas and other gas impurities then enter a water absorption tower, the formaldehyde gas is absorbed by water to obtain formaldehyde aqueous solution, and the impurity gas is discharged from the top of the absorption tower.
The formaldehyde polymerization working section comprises a formaldehyde polymerization rectifying tower, a steam permeation device and a trioxymethylene refining tower. The formaldehyde aqueous solution extracted from the formaldehyde preparation section enters a formaldehyde polymerization rectifying tower to carry out polymerization reaction to generate trioxymethylene, the mixture of the trioxymethylene, the formaldehyde and water is separated by the reaction rectifying tower, part of the mixture is extracted from the tower top in a gas phase form, part of the mixture is refluxed in a liquid phase, and the water which does not participate in the reaction is extracted from the tower bottom after being separated by the reaction rectifying tower. The gas phase mixture of trioxymethylene, formaldehyde and water extracted from the top of the tower enters a vapor permeation device for membrane separation, the water phase penetrates through the membrane and enters the permeation side of the vapor permeation device for extraction, the mixed phase of trioxymethylene, formaldehyde and trace water is extracted from the interception side of the vapor permeation device and then enters a trioxymethylene refining tower, anhydrous trioxymethylene is extracted from the separation tower bottom of the rectifying tower, the liquid phase mixture of trioxymethylene, formaldehyde and water is extracted from the top of the tower, and then enters the vapor permeation device for secondary separation.
The methylal preparation section comprises a methylal reaction rectifying tower. The formaldehyde aqueous solution and methanol in the formaldehyde preparation section are added into a methylal reaction rectifying tower in a form of little excessive formaldehyde for reaction and separation, anhydrous methylal is extracted from the top of the methylal reaction rectifying tower, and water containing little formaldehyde is extracted from the tower bottom.
The reactive distillation preparation section of the polymethoxy dimethyl ether is the same as the first technical scheme.
In the formaldehyde preparation section, the gas phase extraction temperature of a methanol evaporator is 0-5 ℃ higher than the boiling point temperature of methanol under the environment pressure; the mass ratio of the methanol vapor to the oxygen in the gas mixer is that the reactants of methanol and oxygen in the airPreferably, the mass ratio is 0.7-1.5; the pre-reaction preheater is used for preheating the mixture, and the temperature difference between the mixture and the reaction temperature is preferably-20 ℃ to 20 ℃; the reaction catalyst in the oxidation reactor is a metal or metal oxide catalyst, preferably an iron-molybdenum catalyst, and the catalyst usage amount is 50-280kg/m 3 The reaction temperature is preferably 200-800 ℃; the preferable mass ratio of formaldehyde to water in the water absorption tower is 0.4-2.3, the tower internal parts are filler, and the filler height is 1-8 m; the formaldehyde content of the aqueous formaldehyde solution of the product of this stage is preferably 30 to 70%.
In the formaldehyde polymerization working section, a liquid-phase reactant feed inlet is arranged in a reaction section of a formaldehyde polymerization rectifying tower, a reaction separation tower internal part is adopted in the reaction section, catalytic filler or a catalytic tray is adopted in the tower internal part, the catalytic filler height is 2-6 m, 8-30 catalytic trays are adopted in the rectifying section and stripping section, filler or tray is adopted in the rectifying section, the filler is 1-5 m, 4-25 trays are adopted in the stripping section, the filler is 0.5-3 m, and 2-15 trays are adopted in the stripping section; the working pressure of formaldehyde polymerization rectifying tower is preferably 0.1-2 atm, the reflux ratio of tower top is preferably 0.5-5, the catalyst adopts acid resin or acid molecular sieve catalyst, and the catalyst consumption is 20-300 kg/m 3 The method comprises the steps of carrying out a first treatment on the surface of the The permeation side of the pervaporation membrane in the vapor permeation device is operated under negative pressure, the preferable pressure range is 100-600kPa, and the pervaporation membrane is a permeable molecular sieve membrane, preferably a NaA membrane; the internal parts of the trioxymethylene refining tower adopt packing or trays, the height of the packing is 2-6 m, the trays are 8-40, the preferred range of the top operating pressure is 0.5-2atm, and the preferred range of the top reflux ratio is 0.5-5.
In the methylal preparation section, two liquid-phase reactant feed inlets are arranged on a reaction section of a methylal reaction rectifying tower, reaction sections adopt reaction separation tower internals, the tower internals are catalytic packing or catalytic trays, the height of the catalytic packing is 1.5-5 m, the catalytic trays are 6-25, the rectifying section and stripping section adopt packing or trays, the packing of the rectifying section is 1-5 m, the trays are 4-25, the packing of the stripping section is 1-5 m, and the trays are 4-25; the working pressure is preferably 0.3-1.5atm, the mass ratio of formaldehyde to methanol in the formaldehyde aqueous solution as the reaction raw material is preferably 0.46-0.5, the catalyst is an acidic solid catalyst (preferably an acidic molecular sieve catalyst), the catalyst usage amount is preferably 20-300kg/m < 3 >, and the tower top reflux ratio is preferably 0.5-10.
The process device for realizing the second technical scheme comprises a formaldehyde preparation device; formaldehyde polymerization device; a methylal preparation device; the device for preparing the polymethoxy dimethyl ether by reactive distillation comprises a methanol evaporator, a gas mixer, a preheater, an oxidation reactor and a water absorption tower which are connected in sequence; the formaldehyde polymerization device comprises a formaldehyde polymerization rectifying tower, steam permeation equipment and a trioxymethylene refining tower; the methylal preparation device comprises a methylal reaction rectifying tower; the tower kettle extraction outlet of the water absorption tower is respectively connected with the feed inlet of the formaldehyde polymerization reaction rectifying tower and the reactant feed inlet of the methylal reaction rectifying tower through pipelines; the formaldehyde polymerization rectifying tower is provided with a reactant feed inlet; the top outlet of the formaldehyde polymerization rectifying tower is connected with steam permeation equipment, the interception side outlet of the steam permeation equipment is connected with the feed inlet of the trioxymethylene refining tower, and the bottom outlet of the trioxymethylene refining tower is connected with the raw material feed inlet of the polymethoxy dimethyl ether reaction rectifying tower; two reactant feed inlets are arranged on the reaction section of the methylal reaction rectifying tower, and the top extraction outlet of the methylal reaction rectifying tower is connected with the raw material feed inlet of the polymethoxy dimethyl ether reaction rectifying tower through a pipeline. The polymethoxy dimethyl ether reaction rectification preparation device is the same as the device of the first technical proposal.
The third technical scheme of the invention:
the raw materials which are limited to enter the reactive distillation column of the polymethoxy dimethyl ether are anhydrous methylal and anhydrous gaseous formaldehyde.
The process method comprises a formaldehyde preparation working section; a gas-phase formaldehyde preparation section; a methylal preparation section; and (3) a polymethoxy dimethyl ether reaction rectification preparation section. Raw material methanol is subjected to oxidation reaction in a formaldehyde preparation section to generate formaldehyde, a reactor is used for extracting mixed gas containing formaldehyde, an absorption process is carried out on the mixed gas to obtain formaldehyde aqueous solution, and part of formaldehyde aqueous solution is reacted with methanol through a methylal preparation section to obtain anhydrous methylal; part of formaldehyde aqueous solution passes through an evaporator, steam permeation equipment and an adsorption device in a gas-phase formaldehyde preparation working section to obtain anhydrous gas-phase formaldehyde; methylal and gaseous formaldehyde enter a polymethoxy dimethyl ether reaction rectification preparation section and are subjected to a reaction separation-separation process to obtain a high-purity target product DMM3-5.
Wherein the formaldehyde preparation section and the methylal preparation section are the same as the second technical scheme. The reactive distillation preparation section of the polymethoxy dimethyl ether is the same as the first technical scheme.
The gas-phase formaldehyde preparation working section comprises a formaldehyde aqueous solution evaporator, a vapor permeation device and an adsorption device which are connected in sequence. Part of formaldehyde aqueous solution generated by an absorption tower in the formaldehyde preparation section enters a gas-phase formaldehyde preparation section, is changed into a gas phase through an evaporator, enters a vapor permeation device to remove water vapor in a mixed gas phase, and enters an adsorption device to absorb residual water vapor in the mixed gas phase after water removal, so that anhydrous gas-phase formaldehyde is obtained.
In the gas-phase formaldehyde preparation section, the gas-phase extraction temperature of a formaldehyde aqueous solution evaporator is 10-60 ℃ higher than the boiling point temperature of a mixture under the environment pressure; the permeation side of the pervaporation membrane in the vapor permeation device is operated under negative pressure, the preferable pressure range is 100-600kPa, and the pervaporation membrane is a permeable molecular sieve membrane, preferably a NaA membrane; the adsorption device adopts a water vapor adsorption device, and the water content of the gas phase after adsorption is not more than 0.01%.
The device for realizing the technical scheme comprises a formaldehyde preparation device; a gas-phase formaldehyde preparation device; a methylal preparation device; the device for preparing the polymethoxy dimethyl ether by reactive distillation comprises a methanol evaporator, a gas mixer, a preheater, an oxidation reactor and a water absorption tower which are connected in sequence; the gas-phase formaldehyde preparation device comprises a formaldehyde aqueous solution evaporator, steam permeation equipment and an adsorption device which are connected in sequence; the methylal preparation device comprises a methylal reaction rectifying tower; the tower kettle extraction outlet of the water absorption tower is respectively connected with the feed inlet of the formaldehyde aqueous solution evaporator and the reactant feed inlet of the methylal reaction rectifying tower through pipelines; the outlet of the formaldehyde aqueous solution evaporator is connected with steam permeation equipment, the outlet of the steam permeation equipment is connected with an adsorption device, and the outlet of the adsorption device is connected with a raw material feed inlet of the polymethoxy dimethyl ether reaction rectifying tower; two reactant feed inlets are arranged on the reaction section of the methylal reaction rectifying tower, and the top extraction outlet of the methylal reaction rectifying tower is connected with the raw material feed inlet of the polymethoxy dimethyl ether reaction rectifying tower through a pipeline; the polymethoxy dimethyl ether reaction rectification preparation device is the same as the device of the first technical proposal.
The invention has the advantages and beneficial effects that:
1. the reactive distillation process of polymethoxy dimethyl ether adopts methylal and anhydrous chain growth reactants as raw materials, and overcomes the defects of reverse reaction, high separation complexity and the like caused by water to system reaction and separation.
2. The invention uses the advantages of the reactive distillation process, adopts excessive methylal reactant, greatly improves the conversion rate of chain growth reactant, reduces the subsequent separation difficulty caused by the existence of formaldehyde, simultaneously, the reactive distillation can timely bring reaction products away from a reaction zone to prevent the excessive polymerization of polymethoxy dimethyl ether, simultaneously breaks the reaction balance limit, promotes the continuous polymerization of DMM2 to generate target products DMM 3-5, reduces the generation amount of DMM2, reduces the circulation flow strand amount of DMM2 and DMM 6-10, and effectively improves the yield and selectivity of DMM 3-5.
3. The process method of the invention uses low-cost industrial methanol as a single raw material. The process fully plays the advantages of the reactive rectifying tower, effectively controls the reaction residence time, breaks the reaction balance limit, improves the reaction conversion rate of each reaction in the process, and can prevent the reaction from going to the direction of larger polymerization degree in the polymerization process of the polymethoxy dimethyl ether, thereby improving the yield and selectivity of the target product DMM 3-5.
4. The invention removes water in the reactant by using the vapor permeation equipment, eliminates the azeotropic condition between each substance and water in the process system, and ensures that the gaseous formaldehyde or paraformaldehyde completely reacts by excessive addition of methylal in reactive distillation in the preparation process of the polymethoxy dimethyl ether, thereby reducing the complexity of the product refining process caused by the existence of formaldehyde and water.
5. The invention can finish the refining process of gas-phase formaldehyde by only using two vapor permeation devices and one air separation tower, and can finish the refining process of trioxymethylene reactant by only using one vapor permeation device and one rectifying tower, thereby effectively shortening the process flow and the number of process devices and reducing the energy consumption.
6. The reaction temperature, the reaction residence time and the reaction process in the polymethoxy dimethyl ether reaction rectifying tower are controllable, the advantages of the reaction rectification can be fully utilized to timely separate substances above a reaction product DMM3 from a reaction zone, the generation trend of substances with excessive polymerization degree is reduced, the conversion rate of reactants and the reaction yield of target products DMM 3-5 are improved, and the material quantity of a circulating flow strand is reduced.
Drawings
FIG. 1 is a schematic view of a process flow of a first embodiment of the present invention;
FIG. 2 is a schematic diagram of a process flow according to a second embodiment of the present invention;
Fig. 3 is a schematic process flow diagram of a third embodiment of the present invention.
Detailed Description
The invention will now be described in further detail by way of specific examples, which are given by way of illustration only and not by way of limitation, with reference to the accompanying drawings.
The first solution is shown in fig. 1.
A reactive distillation process method for synthesizing polymethoxy dimethyl ether comprises the following steps:
step 1, respectively feeding methylal for providing product chain end capping and trioxymethylene for providing product chain growth, paraformaldehyde or a mixture of substances from a methylal mixer and a chain growth reactant feeding pipeline through two liquid-phase feeding ports on a reaction section of a polymethoxy dimethyl ether reaction rectifying tower 1, or respectively feeding methylal and gaseous formaldehyde from a raw material liquid-phase feeding port and a gaseous-phase feeding port on the polymethoxy dimethyl ether reaction rectifying tower for reaction;
step 2, separating a reaction zone from a high boiling point product DMM 3-10 (containing trace DMM 2) generated by the reaction through a stripping section of a polymethoxy dimethyl ether reaction rectifying tower, extracting liquid phase from a tower bottom of the polymethoxy dimethyl ether reaction rectifying tower, separating a reaction zone from a low polymerization degree product DMM2 generated by the reaction and unreacted methylal through a rectifying section of the polymethoxy dimethyl ether reaction rectifying tower, and extracting liquid phase pipelines from the top of the polymethoxy dimethyl ether reaction rectifying tower; the top of the polymethoxy dimethyl ether reaction rectifying tower is provided with a complete condenser 7, and the bottom of the tower is provided with a reboiler 8.
Step 3, conveying a liquid phase extracted from the tower bottom of the polymethoxy dimethyl ether reaction rectifying tower to a primary product refining tower 4 and a secondary product refining tower 5 for product refining, conveying DMM2 separated from the tower top of the primary product refining tower to a DMM2 mixer 3, and extracting high-purity target products DMM 3-5 separated from the tower top of the secondary product refining tower from a liquid phase extraction pipeline at the tower top; the product DMM 6-10 with the excessively high polymerization degree is separated from the tower kettle, is extracted from a liquid phase output pipeline of the tower kettle and is conveyed to a circulating material feed inlet of the polymethoxy dimethyl ether reaction rectifying tower;
and step 4, carrying out total return operation on the tower top or total reflux of the polymethoxy dimethyl ether reaction rectifying tower, returning the mixture to the tower top of the polymethoxy dimethyl ether reaction rectifying tower, or carrying out liquid phase extraction according to a certain reflux ratio, then conveying the mixture to a light component separating tower 2 for light component separation, separating a low-polymerization-degree product DMM2 from the tower bottom of the light component separating tower, mixing the low-polymerization-degree product DMM2 with the DMM2 separated from the tower top of the primary product refining tower through a DMM2 mixer, returning the mixture to a polymethoxy dimethyl ether reaction rectifying tower reaction zone for secondary reaction, and mixing methylal extracted from the tower top into a methylal mixer 6 with methylal raw materials and then conveying the mixture into the polymethoxy dimethyl ether reaction rectifying tower for reaction.
The technology and the equipment are widely applicable to the preparation of the polymethoxy dimethyl ether by the reaction of methylal and anhydrous chain growth reactants (trioxymethylene, paraformaldehyde and gas-phase formaldehyde), and three application examples are selected for illustration in order to better illustrate the advantages of the invention in reaction conversion rate, product purity and product yield, but the application scope of the technology and the equipment is not limited.
Example 1:
the method is used for preparing the polymethoxy dimethyl ether by the reaction of methylal and trioxymethylene under the acidic condition, and has the same flow as the process, and comprises a polymethoxy dimethyl ether reaction rectifying tower, a primary product refining tower, a secondary product refining tower and a light componentA separation tower, a methylal mixer and a DMM2 mixer. Methylal and trioxymethylene respectively enter the polymethoxy dimethyl ether reaction rectifying tower from two liquid-phase feed inlets on the reaction section, and the methylal feed inlet is arranged below the trioxymethylene feed inlet. The mass ratio of polyoxymethylene to methylal serving as the raw material of the polymethoxy dimethyl ether reactive distillation column is 4.5, the working pressure of the polymethoxy dimethyl ether reactive distillation column is absolute 4atm, the reflux ratio of the top of the column is 0.5, the catalyst adopts an acid resin catalyst, and the preferred use amount of the catalyst is 200kg/m 3 The internal part of the reaction section of the polymethoxy dimethyl ether reaction rectifying tower is catalytic filler, and the height of the catalytic filler is 4 meters; the rectifying section and the stripping section tower internals are fillers, the height of the rectifying section filler is 3 meters, and the height of the stripping section filler is 3 meters. The operation pressure at the top of the primary product refining tower is 1atm absolute pressure, the reflux ratio at the top of the tower is 0.1, the internal parts of the tower are filled with the filler, and the height of the filler is 3 meters; the operation pressure at the top of the secondary product refining tower is 1atm absolute pressure, the preferable range of the reflux ratio at the top of the tower is 0.2, the internal parts of the tower are filled, and the height of the filled material is 4 meters. The operating pressure at the top of the light component separation tower is absolute pressure 0.5atm, the preferable range of the reflux ratio at the top of the tower is 0.1, the internal parts of the tower are filled, and the height of the filled is 4 meters.
After the process, the conversion rate of the reactant trioxymethylene can reach 99.5%, the purity of the target product DMM 3-5 can reach 99.6%, and the total yield of the DMM 3-5 can reach more than 98.5%.
Example 2:
the method is used for preparing the polymethoxy dimethyl ether by reacting methylal and paraformaldehyde under the acidic condition, and has the same flow as the process, and comprises a polymethoxy dimethyl ether reaction rectifying tower, a primary product refining tower, a secondary product refining tower, a light component separating tower, a methylal mixer and a DMM2 mixer. Methylal and paraformaldehyde enter the polymethoxy dimethyl ether reaction rectifying tower from two liquid phase feed inlets on the reaction section respectively, and the methylal feed inlet is arranged below the paraformaldehyde feed inlet. The mass ratio of the raw materials of the polymetaldehyde and the methylal of the polymethoxydimethyl ether reaction rectifying tower is 2, the working pressure of the polymethoxydimethyl ether reaction rectifying tower is absolute 2atm, the reflux ratio of the tower top is total reflux, and the catalyst adopts an acidic molecular sieve catalyst to catalyzeThe dosage of the chemical agent is 100kg/m 3 The internal part of the reaction section of the polymethoxy dimethyl ether reaction rectifying tower is a catalytic tray, and the number of the catalytic trays is 25; the rectifying section and stripping section tower internals are trays, the number of trays is 20, and the number of trays is 15. The tower top operation pressure of the primary product refining tower is 0.5atm absolute, the tower top reflux ratio is 2, tower internals are trays, and the trays are 30; the operating pressure at the top of the secondary product refining tower is 0.5atm, the reflux ratio at the top of the tower is 1.5, tower internals are trays, and the trays are 30. .
After the process, the conversion rate of the reactant paraformaldehyde can reach 99.3 percent, the purity of the target product DMM 3-5 can reach 99.5 percent, and the total yield of the DMM 3-5 can reach more than 98 percent.
Example 3:
the method is used for preparing the polymethoxy dimethyl ether by reacting methylal and gaseous formaldehyde under the acidic condition, and has the same flow as the process, and comprises a polymethoxy dimethyl ether reaction rectifying tower, a primary product refining tower, a secondary product refining tower, a light component separating tower, a methylal mixer and a DMM2 mixer. Methylal and gaseous formaldehyde respectively enter the polymethoxy dimethyl ether reaction rectifying tower from a liquid phase feed inlet on the reaction section and a gaseous phase feed inlet of the stripping section, and the methylal feed inlet is above the gaseous formaldehyde feed inlet. The mass ratio of the gaseous formaldehyde to methylal serving as the raw material of the polymethoxy dimethyl ether reactive distillation column is 0.6, the working pressure of the polymethoxy dimethyl ether reactive distillation column is absolute 7atm, the reflux ratio of the top of the column is 5, the catalyst adopts an acid resin catalyst, and the catalyst usage amount is 300kg/m 3 The internal part of the reaction section of the polymethoxy dimethyl ether reaction rectifying tower is catalytic filler, and the height of the catalytic filler is 3.5 meters; the rectifying section and the stripping section tower internals are fillers, the height of the rectifying section filler is 2.5 meters, and the height of the stripping section filler is 2 meters. The operation pressure at the top of the primary product refining tower is 1.5atm, the reflux ratio at the top of the tower is 5, the internal parts of the tower are filled with the filler, and the height of the filler is 3.5 meters; the operating pressure at the top of the secondary product refining tower is 1.5atm, the reflux ratio at the top of the tower is 3, the internal parts of the tower are filled, and the height of the filled material is 3.5 m. The operating pressure at the top of the light component separation tower is 1.8atm, the reflux ratio at the top of the tower is 3, the internal parts of the tower are filled with the filler, and the height of the filler is 2 meters.
After the process, the conversion rate of reactant formaldehyde can reach 99.2%, the purity of the target product DMM3-5 can reach 99.1%, and the total yield of the DMM3-5 can reach more than 97.8%.
The second solution is shown in fig. 2.
A process method for preparing DMMn by methylal and trioxymethylene route methanol comprises a formaldehyde preparation section; a formaldehyde polymerization section; a methylal preparation section; and (3) a polymethoxy dimethyl ether reaction rectification preparation section. Raw material methanol is subjected to oxidation reaction, absorption and other processes in a formaldehyde preparation section to obtain formaldehyde aqueous solution, part of the product is subjected to reaction separation-separation process in a formaldehyde polymerization section to obtain anhydrous trioxymethylene, the other part of the product is subjected to reaction with methanol in a methylal preparation section to obtain anhydrous methylal, and methylal and trioxymethylene enter a polymethoxy dimethyl ether reaction rectification preparation section to obtain a high-purity target product DMM3-5 through the reaction separation-separation process.
The formaldehyde preparation section comprises a methanol evaporator 9, a gas mixer 10, a preheater 11, an oxidation reactor 12 and a water absorption tower 13 which are connected in sequence. Raw material industrial methanol is gasified into methanol gas by a methanol evaporator and then enters a gas mixer to be mixed with oxygen; the mixed gas is preheated to the reaction temperature by a preheater and then enters an oxidation reactor for methanol oxidation reaction to obtain formaldehyde gas; the formaldehyde gas and other gas impurities then enter a water absorption tower, the formaldehyde gas is absorbed by water to obtain formaldehyde aqueous solution, and the impurity gas is discharged from the top of the absorption tower.
The formaldehyde polymerization section comprises a formaldehyde polymerization rectifying tower 14, a steam permeation device 15 and a trioxymethylene refining tower 16. The formaldehyde aqueous solution extracted from the formaldehyde preparation section enters a formaldehyde polymerization rectifying tower to carry out polymerization reaction to generate trioxymethylene, the mixture of the trioxymethylene, formaldehyde and water is separated by the formaldehyde polymerization rectifying tower, part of the mixture is extracted from the tower top in a gas phase form, part of the mixture is refluxed in a liquid phase, and the water which does not participate in the reaction is separated by the formaldehyde polymerization rectifying tower and is extracted from the tower bottom. The gas phase mixture of the trioxymethylene, the formaldehyde and the water extracted from the tower top enters the steam permeation equipment for membrane separation, the water phase penetrates through the membrane and enters the permeation side of the steam permeation equipment for extraction, the mixed phase of the trioxymethylene, the formaldehyde and the trace water is extracted from the interception side of the steam permeation equipment and then enters the trioxymethylene refining tower, the anhydrous trioxymethylene is extracted from the separation tower bottom of the trioxymethylene rectifying tower, the liquid phase mixture of the trioxymethylene, the formaldehyde and the water is extracted from the tower top, and then enters the steam permeation equipment for secondary separation.
The methylal preparation section comprises a methylal reaction rectifying tower 17. The formaldehyde aqueous solution and methanol in the formaldehyde preparation section are added into a methylal reaction rectifying tower in a form of little excessive formaldehyde for reaction and separation, anhydrous methylal is extracted from the top of the methylal reaction rectifying tower, and water containing little formaldehyde is extracted from the tower bottom.
The reactive distillation preparation section of the polymethoxy dimethyl ether is the same as the first technical scheme.
In order to better illustrate the advantages of the invention in terms of reaction conversion, product purity, product yield and energy consumption, 3 examples of applications are chosen for illustration, but the application scope of the technology and the equipment is not limited thereby.
Example 4
In the formaldehyde preparation section, the gas phase extraction temperature of a methanol evaporator is higher than the boiling point temperature of methanol under the environment pressure by 0 ℃; the mass ratio of the methanol steam to the oxygen in the gas mixer is 1.5; the pre-reaction preheater is used for preheating the mixture, and the difference between the preheating temperature and the reaction temperature is 20 ℃; the reaction catalyst in the oxidation reactor is an iron-molybdenum catalyst, and the dosage of the catalyst is 280kg/m 3 The reaction temperature of the oxidation reactor is 200 ℃; the mass ratio of formaldehyde to water in the water absorption tower is 0.4, and the height of the filler is 6 meters; the formaldehyde content of the formaldehyde aqueous solution of the product of the working section is 30 percent.
In the formaldehyde polymerization working section, the working pressure of a formaldehyde polymerization rectifying tower is absolute pressure 0.1atm, the reflux ratio of the tower top is 5, the catalyst is an acid resin catalyst, and the catalyst usage amount is 300kg/m 3 The catalytic packing height of the reaction section of the formaldehyde polymerization rectifying tower is 4 meters, the packing of the rectifying section is 2 meters, and the packing of the stripping section is 1 meter; the pressure of the vapor permeation device is 600kPa; the top operating pressure of the trioxymethylene refining tower is absolute The pressure was 2atm, the overhead reflux ratio was 5, and the packing height was 5 m.
In the methylal preparation section, the working pressure of a methylal reaction rectifying tower is 0.3atm, the mass ratio of formaldehyde to methanol in a formaldehyde aqueous solution serving as a reaction raw material is 0.5, an acid molecular sieve catalyst is adopted as a catalyst, and the using amount of the catalyst is 300kg/m 3 The reflux ratio of the top of the tower is 0.5, the height of the catalytic packing in the reaction section is 3 meters, the packing in the rectifying section is 3 meters, and the packing in the stripping section is 3 meters.
In the polymethoxy dimethyl ether reaction rectification preparation section, the working pressure of a polymethoxy dimethyl ether reaction rectification column is absolute pressure 6atm, the mass ratio of the trioxymethylene to methylal serving as a reaction raw material is 0.6, the catalyst is an acidic resin catalyst, and the using amount of the catalyst is 200kg/m 3 The reflux ratio of the top of the tower is 5, the height of the catalytic packing in the reaction section is 4 meters, the height of the packing in the rectifying section is 3 meters, and the height of the packing in the stripping section is 3 meters; the tower top operation pressure of the primary product refining tower is absolute pressure 0.5atm, the tower top reflux ratio is 0.1, and the packing height is 3 meters; the operating pressure of the tower top of the inner part of the secondary product refining tower is 0.5atm, the reflux ratio of the tower top is 0.2, and the packing height is 4 meters; the operating pressure at the top of the light component separation tower is 0.5atm, the reflux ratio at the top of the tower is 0.1, and the packing height is 4 meters.
After the process, the total conversion rate of reactant methanol can reach 99.3%, the purity of target product DMM 3-5 can reach 99.4%, and the total yield of DMM 3-5 can reach more than 98.2%.
Example 5
In the formaldehyde preparation section, the gas phase extraction temperature of a methanol evaporator is 5 ℃ higher than the boiling point temperature of methanol under the environment pressure; the mass ratio of the methanol steam to the oxygen in the gas mixer is 1.5; the pre-reaction preheater is used for preheating the mixture, and the difference between the pre-reaction temperature and the reaction temperature is-20 ℃; iron-molybdenum catalyst as reaction catalyst in oxidation reactor with catalyst consumption of 80kg/m 3 The reaction temperature is 800 ℃; the mass ratio of formaldehyde to water in the water absorption tower is 2.3, and the height of the filler is 5 meters; the formaldehyde content of the formaldehyde aqueous solution of the product of the working section is 70 percent.
In the formaldehyde polymerization working section, the working pressure of a formaldehyde polymerization rectifying tower is absolute pressure 2atm, and the top of the tower is provided with a plurality of rectifying unitsReflux ratio of 0.5, catalyst of acidic molecular sieve, catalyst usage amount of 50kg/m 3 20 catalyst trays in the reaction section, 15 trays in the rectifying section and 10 trays in the stripping section; the pressure of the vapor permeation device is 100kPa; the operation pressure at the top of the trioxymethylene refining tower is 0.5atm, the reflux ratio at the top of the tower is 0.5, and the tower tray is 35 blocks.
In the methylal preparation section, the working pressure of a methylal reaction rectifying tower is 1.5atm absolute, the mass ratio of formaldehyde to methanol in a formaldehyde aqueous solution serving as a reaction raw material is 0.46, a catalyst is an acidic molecular sieve catalyst, the catalyst usage amount is 20kg/m < 3 >, the reflux ratio of the top of the tower is 10, the number of catalyst trays in a reaction section is 15, the number of trays in a rectifying section is 15, and the number of trays in a stripping section is 15.
In the polymethoxy dimethyl ether reaction rectification preparation section, the working pressure of a polymethoxy dimethyl ether reaction rectification column is absolute pressure 2atm, the mass ratio of reaction raw material trioxymethylene to methylal is 4.5, the catalyst is an acidic molecular sieve catalyst, the catalyst usage amount is 300kg/m < 3 >, the reflux ratio of the top of the tower is total reflux, the catalytic tower tray of the reaction section is 25, the tower tray of the rectification section is 20, and the tower tray of the stripping section is 15; the tower top operation pressure of the primary product refining tower is 1.5atm absolute, the tower top reflux ratio is 5, and the tower tray is 30 blocks; the tower top operation pressure of the inner part of the secondary product refining tower is 1.5atm absolute, the tower top reflux ratio is 3, and the tower tray is 30 blocks; and the polymethoxy dimethyl ether reaction rectifying tower is in full reflux operation, so that the tower top extract does not need to pass through a light component separating tower.
After the process, the total conversion rate of reactant methanol can reach 99.5%, the purity of target product DMM 3-5 can reach 99.5%, and the total yield of DMM 3-5 can reach more than 98.1%.
Example 6
In the formaldehyde preparation section, the gas phase extraction temperature of a methanol evaporator is 3 ℃ higher than the boiling point temperature of methanol under the environment pressure; the mass ratio of the methanol steam to the oxygen in the gas mixer is 1.2; the pre-reaction preheater is used for preheating the mixture, and the difference between the preheating temperature and the reaction temperature is 10 ℃; the reaction catalyst in the oxidation reactor is an iron-molybdenum catalyst, and the dosage of the catalyst is 150kg/m 3 Oxygen, oxygenThe reaction temperature in the chemical reactor is 600 ℃; the mass ratio of formaldehyde to water in the water absorption tower is 2, and the filler is 6 meters; the formaldehyde content of the formaldehyde aqueous solution of the product of the working section is 67%.
In the formaldehyde polymerization working section, the working pressure of a formaldehyde polymerization rectifying tower is absolute pressure 1atm, the reflux ratio of the tower top is 1, the catalyst is an acid resin catalyst, and the catalyst usage amount is 200kg/m 3 The height of the catalytic packing in the reaction section is 4.5 m, the packing in the rectifying section is 2.5 m, and the packing in the stripping section is 0.5 m; the pressure of the vapor permeation device is 400kPa; the operating pressure at the top of the trioxymethylene refining tower is 0.8atm, the reflux ratio at the top of the tower is 1.5, and the height of the filling material is 4 meters.
In the methylal preparation section, the working pressure of a methylal reaction rectifying tower is 1atm absolute, the mass ratio of formaldehyde to methanol in a formaldehyde aqueous solution serving as a reaction raw material is 0.5, a catalyst is an acidic molecular sieve catalyst, the catalyst usage amount is 150kg/m < 3 >, the reflux ratio of the top of the tower is 2, the catalytic packing height of a reaction section is 4 m, the packing of the rectifying section is 2 m, and the packing of a stripping section is 2 m.
In the polymethoxy dimethyl ether reaction rectification preparation section, the working pressure of a polymethoxy dimethyl ether reaction rectification column is 5atm absolute, the mass ratio of reaction raw material trioxymethylene to methylal is 4, an acid resin catalyst is adopted as a catalyst, the catalyst usage amount is 220kg/m < 3 >, the reflux ratio of the tower top is 1, the catalytic packing height of a reaction section is 3.5 m, the packing height of a rectification section is 2.5 m, and the packing height of a stripping section is 2 m; the tower top operation pressure of the primary product refining tower is 1atm absolute, the tower top reflux ratio is 0.8, and the packing height is 3.5 m; the operating pressure of the tower top of the inner part of the secondary product refining tower is 1atm absolute, the reflux ratio of the tower top is 2, and the packing height is 3.5 m; the operating pressure at the top of the light component separation tower is 1atm absolute, the reflux ratio at the top of the tower is 2, and the height of the packing is 2 meters.
After the above process, the total conversion rate of reactant methanol can reach 99.6%, the purity of target product DMM3-5 can reach 99.5%, and the total yield of DMM3-5 can reach more than 98.8%.
A third solution is shown in fig. 3.
A technological process for preparing polymethoxy dimethyl ether by methanol comprises a formaldehyde preparation section; a gas-phase formaldehyde preparation section; a methylal preparation section; and (3) a polymethoxy dimethyl ether reaction rectification preparation section. Raw material methanol is subjected to oxidation reaction in a formaldehyde preparation section to generate formaldehyde, a reactor is used for extracting mixed gas containing formaldehyde, an absorption process is carried out on the mixed gas to obtain formaldehyde aqueous solution, and part of formaldehyde aqueous solution is reacted with methanol through a methylal preparation section to obtain anhydrous methylal; part of formaldehyde aqueous solution passes through an evaporator, steam permeation equipment and an adsorption device in a gas-phase formaldehyde preparation working section to obtain anhydrous gas-phase formaldehyde; methylal and gaseous formaldehyde enter a polymethoxy dimethyl ether reaction rectification preparation section and are subjected to a reaction separation-separation process to obtain a high-purity target product DMM3-5.
The formaldehyde preparation working section and the methylal preparation working section are the same as the second technical scheme. The reactive distillation preparation section of the polymethoxy dimethyl ether is the same as the first technical scheme.
The gas-phase formaldehyde preparation section comprises a formaldehyde aqueous solution evaporator 18, a vapor permeation device 19 and an adsorption device 20 which are connected in sequence. Part of formaldehyde aqueous solution generated by an absorption tower in the formaldehyde preparation section enters a gas-phase formaldehyde preparation section, is changed into a gas phase through an evaporator, enters a vapor permeation device to remove water vapor in a mixed gas phase, and enters an adsorption device to absorb residual water vapor in the mixed gas phase after water removal, so that anhydrous gas-phase formaldehyde is obtained.
In order to better illustrate the advantages of the invention in terms of reaction conversion, product purity, product yield and energy consumption, 3 examples of applications are chosen for illustration, but the application scope of the technology and the equipment is not limited thereby.
Example 7
In the formaldehyde preparation section, the gas phase extraction temperature of a methanol evaporator is higher than the boiling point temperature of methanol under the environment pressure by 0 ℃; the mass ratio of the methanol steam to the oxygen in the gas mixer is 0.7; the difference between the mixture preheating temperature of the preheater before reaction and the reaction temperature is-20 ℃; the reaction temperature of the oxidation reactor is 800 ℃, the reaction catalyst in the oxidation reactor is an iron-molybdenum catalyst, and the dosage of the catalyst is 80kg/m 3 The method comprises the steps of carrying out a first treatment on the surface of the The mass ratio of formaldehyde to water in the water absorption tower is 0.4, and the height of the filler is 6 meters; the product of this sectionThe formaldehyde content of the aqueous formaldehyde solution was 30%.
In the gas-phase formaldehyde preparation section, the gas-phase extraction temperature of a formaldehyde aqueous solution evaporator is 10 ℃ higher than the boiling point temperature of a mixture under the environment pressure; the permeation side of the pervaporation membrane in the vapor permeation device is operated under negative pressure, the pressure is 100kPa, the adsorption device adopts a vapor adsorption device, and the water content of the gas phase after adsorption is 0.009%.
In the methylal preparation section, the working pressure of a methylal reaction rectifying tower is 0.3atm, the mass ratio of formaldehyde to methanol in a formaldehyde aqueous solution serving as a reaction raw material is 0.5, an acidic molecular sieve catalyst is adopted as a catalyst, and the using amount of the catalyst is 50kg/m 3 The reflux ratio of the top of the tower is 0.5, the height of the catalytic packing in the reaction section is 3 meters, the packing in the rectifying section is 3 meters, and the packing in the stripping section is 3 meters.
In the polymethoxy dimethyl ether reaction rectification preparation section, the working pressure of a polymethoxy dimethyl ether reaction rectification column is absolute pressure 2atm, the mass ratio of the gaseous formaldehyde of the reaction raw material to methylal is 4.5, the catalyst is an acid resin catalyst, and the catalyst usage amount is 300kg/m 3 The reflux ratio of the top of the tower is total reflux, the number of the catalyst trays in the reaction section is 25, the number of the trays in the rectifying section is 20, and the number of the trays in the stripping section is 15; the tower top operation pressure of the primary product refining tower is absolute pressure 0.5atm, the tower top reflux ratio is 0.1, and the packing height is 3 meters; the operating pressure at the top of the secondary product refining tower is 0.5atm, the reflux ratio at the top of the tower is 0.2, and the packing height is 4 meters.
After the process, the total conversion rate of reactant methanol can reach 98.8%, the purity of target product DMM 3-5 can reach 99.2%, and the total yield of DMM 3-5 can reach more than 98.0%.
Example 8
In the formaldehyde preparation section, the gas phase extraction temperature of a methanol evaporator is 5 ℃ higher than the boiling point temperature of methanol under the environment pressure; the mass ratio of the methanol steam to the oxygen in the gas mixer is 1.5; the difference between the mixture preheating temperature of the preheater before reaction and the reaction temperature is 20 ℃; the reaction temperature of the oxidation reactor is 200 ℃, the catalyst is an iron-molybdenum catalyst, and the catalyst dosage is 280kg/m 3 The method comprises the steps of carrying out a first treatment on the surface of the The mass ratio of formaldehyde to water feed in the water absorption tower is 2.3, and the filling height is5 meters; the formaldehyde content of the formaldehyde aqueous solution of the product of the working section is 70 percent.
In the gas-phase formaldehyde preparation section, the gas-phase extraction temperature of a formaldehyde aqueous solution evaporator is 60 ℃ higher than the boiling point temperature of a mixture under the environmental pressure; the permeation side of the pervaporation membrane in the vapor permeation device is operated under negative pressure, the pressure is 600kPa, the adsorption device adopts a vapor adsorption device, and the water content of the gas phase after adsorption is 0.009%.
In the methylal preparation section, the working pressure of a methylal reaction rectifying tower is 1.5atm absolute pressure, the mass ratio of formaldehyde to methanol in a formaldehyde aqueous solution serving as a reaction raw material is 0.46, a catalyst is an acidic molecular sieve catalyst, and the using amount of the catalyst is 300kg/m 3 The reflux ratio of the top of the tower is 10, the number of the catalyst trays in the reaction section is 15, the number of the trays in the rectifying section is 15, and the number of the trays in the stripping section is 15.
In the polymethoxy dimethyl ether reaction rectification preparation section, the working pressure of a polymethoxy dimethyl ether reaction rectification column is 7atm absolute pressure, the mass ratio of the gaseous formaldehyde of the reaction raw material to methylal is 0.6, the catalyst is an acid resin catalyst, and the catalyst usage amount is 50kg/m 3 The reflux ratio of the top of the tower is 0.1, the height of the catalytic packing of the reaction section is 4 meters, the height of the packing of the rectifying section is 3 meters, and the height of the packing of the stripping section is 3 meters; the tower top operation pressure of the primary product refining tower is 1.5atm absolute, the tower top reflux ratio is 5, and the tower tray is 30 blocks; the operating pressure at the top of the second-stage product refining tower is 1.5atm, the reflux ratio at the top of the tower is 3, and the tower tray is 30 blocks; the operating pressure at the top of the light component separation tower is 1.8atm, the reflux ratio at the top of the tower is 3, and the tower tray is 35 blocks.
After the above process, the total conversion rate of reactant methanol can reach 99.1%, the purity of target product DMM 3-5 can reach 99.1%, and the total yield of DMM 3-5 can reach more than 97.9%.
Example 9
In the formaldehyde preparation section, the gas phase extraction temperature of a methanol evaporator is 3 ℃ higher than the boiling point temperature of methanol under the environment pressure; the mass ratio of the methanol steam to the oxygen in the gas mixer is 0.9; the difference between the mixture preheating temperature of the preheater before reaction and the reaction temperature is-5 ℃; the reaction temperature of the oxidation reactor is 600 ℃ and the reaction is carried out in the oxidation reactor The catalyst is an iron-molybdenum catalyst, and the dosage of the catalyst is 150kg/m 3 The method comprises the steps of carrying out a first treatment on the surface of the The mass ratio of formaldehyde to water in the water absorption tower is 2, and the filler is 6 meters; the formaldehyde content of the formaldehyde aqueous solution of the product of the working section is 67%.
In the gas-phase formaldehyde preparation section, the gas-phase extraction temperature of a formaldehyde aqueous solution evaporator is 50 ℃ higher than the boiling point temperature of a mixture under the environment pressure; the permeation side of the pervaporation membrane in the vapor permeation device is operated under negative pressure, the pressure is 400kPa, the adsorption device adopts a vapor adsorption device, and the water content of the gas phase after adsorption is 0.007%.
In the methylal preparation section, the working pressure of a methylal reaction rectifying tower is 1atm absolute, the mass ratio of formaldehyde to methanol in a formaldehyde aqueous solution serving as a reaction raw material is 0.5, a catalyst is an acidic molecular sieve catalyst, the catalyst usage amount is 300kg/m < 3 >, the reflux ratio of the top of a tower is 3, the catalytic packing height of a reaction section is 4 m, the packing of the rectifying section is 2 m, and the packing of a stripping section is 2 m.
In the polymethoxy dimethyl ether reaction rectification preparation section, the working pressure of a polymethoxy dimethyl ether reaction rectification column is absolute pressure 6atm, the mass ratio of reaction raw material gas phase formaldehyde to methylal is 3, an acid resin catalyst is adopted as a catalyst, the catalyst usage amount is 200kg/m < 3 >, the reflux ratio of the tower top is 2, the catalytic packing height of a reaction section is 3.5 m, the packing height of a rectification section is 2.5 m, and the packing height of a stripping section is 2 m; the tower top operation pressure of the primary product refining tower is 1atm absolute, the tower top reflux ratio is 0.5, and the packing height is 3.5 meters; the operating pressure at the top of the second-stage product refining tower is 1atm absolute, the reflux ratio at the top of the tower is 2, and the height of the filling material is 3.5 m; the operating pressure at the top of the light component separation tower is 1atm absolute, the reflux ratio at the top of the tower is 2, and the height of the packing is 2 meters.
After the process, the total conversion rate of reactant methanol can reach 99.1%, the purity of target product DMM 3-5 can reach 99.3%, and the total yield of DMM 3-5 can reach more than 98.2%.
While the present invention has been described with reference to the preferred embodiments, it will be apparent to one skilled in the art that the present invention may be practiced with modification and alteration of the apparatus and process described herein and with appropriate composition and composition without departing from the spirit and scope of the invention. It is expressly intended that all such similar substitutes and modifications apparent to those skilled in the art are deemed to be included within the spirit, scope and content of the invention.

Claims (7)

1. A reactive distillation process method for synthesizing polymethoxy dimethyl ether is characterized in that:
feeding methylal for providing product chain end capping and raw materials for providing product chain growth through two feed inlets on a reaction section of a polymethoxy dimethyl ether reaction rectifying tower respectively; filling a solid acid catalyst in a reaction section, separating a reaction zone from a reaction section of a high boiling point product DMM 3-10 and a part of a low polymerization degree product DMM2 generated by the reaction through a stripping section of a polymethoxy dimethyl ether reaction rectifying tower, extracting liquid phase from the bottom of the polymethoxy dimethyl ether reaction rectifying tower, separating a reaction zone from a reaction section of the polymethoxy dimethyl ether reaction rectifying tower and extracting liquid phase pipelines from the top of the polymethoxy dimethyl ether reaction rectifying tower;
The extracted liquid of the bottom of the polymethoxy dimethyl ether reaction rectifying tower is sequentially conveyed to a first-stage product refining tower and a second-stage product refining tower for product refining, DMM2 separated from the top of the first-stage product refining tower is conveyed to a DMM2 mixer, and DMM3-5 separated from the top of the second-stage product refining tower is extracted from a liquid phase extraction pipeline at the top of the tower; the product DMM 6-10 with the excessively high polymerization degree is separated from the tower kettle, is extracted from a liquid phase output pipeline of the tower kettle and is conveyed to a circulating material feed inlet of the polymethoxy dimethyl ether reaction rectifying tower;
the method comprises the steps of carrying out overhead or total reflux operation on a polymethoxy dimethyl ether reaction rectifying tower, returning all the mixture to the polymethoxy dimethyl ether reaction rectifying tower overhead, or carrying out liquid phase extraction at a certain reflux ratio, then conveying the mixture to a light component separating tower for light component separation, separating a low-polymerization-degree product DMM2 from a tower bottom of the light component separating tower, mixing the low-polymerization-degree product DMM2 with the DMM2 separated from the top of a primary product refining tower through a mixer, returning the mixture to a polymethoxy dimethyl ether reaction rectifying tower reaction zone for secondary reaction, and mixing methylal extracted from the overhead into methylal and a mixer, and then conveying the mixture into the polymethoxy dimethyl ether reaction rectifying tower for reaction.
2. The reactive distillation process for the synthesis of polymethoxy dimethyl ether according to claim 1, wherein: the process method also comprises a preparation process of the methylal with end capped product chains and the raw material for providing product chain extension, wherein the raw material for providing product chain extension is trioxymethylene, methanol is used as a starting raw material in the preparation process, the raw material comprises a formaldehyde preparation working section, a formaldehyde polymerization working section and a methylal preparation working section, raw material methanol is subjected to oxidation reaction in the formaldehyde preparation working section and a water absorption process to obtain formaldehyde aqueous solution, the formaldehyde aqueous solution is respectively fed into the formaldehyde polymerization working section and the methylal preparation working section, anhydrous trioxymethylene is obtained in the formaldehyde polymerization working section through a reaction separation-separation process, the methylal preparation working section is reacted with methanol to obtain anhydrous methylal, and the anhydrous methylal and the anhydrous trioxymethylene are fed into a polymethoxy dimethyl ether reaction rectifying tower to obtain a high-purity target product DMM3-5 through the reaction separation-separation process.
3. The reactive distillation process for the synthesis of polymethoxy dimethyl ether according to claim 1, wherein: the process method also comprises the preparation process of the methylal with end capped product chains and the raw materials for providing product chain growth, wherein the raw materials for providing product chain growth are anhydrous gaseous formaldehyde, methanol is used as a starting raw material in the preparation process, the raw materials comprise a formaldehyde preparation working section, a gaseous formaldehyde preparation working section and a methylal preparation working section, raw material methanol is subjected to oxidation reaction in the formaldehyde preparation working section to generate formaldehyde, formaldehyde aqueous solution is obtained through a water absorption process, and part of formaldehyde aqueous solution is reacted with methanol through the methylal preparation working section to obtain anhydrous methylal; part of formaldehyde aqueous solution is processed by a gas-phase formaldehyde preparation working section to obtain anhydrous gas-phase formaldehyde; the anhydrous methylal and anhydrous gaseous formaldehyde enter a polymethoxy dimethyl ether reaction rectifying tower to obtain a high-purity target product DMM3-5 through a reaction separation-separation process.
4. A reactive distillation process for the synthesis of polymethoxy dimethyl ether according to claim 2 or 3, wherein: the formaldehyde preparation working section comprises a methanol evaporator, a gas mixer, a preheater, an oxidation reactor and a water absorption tower which are connected in sequence, raw material industrial methanol is gasified into methanol gas through the methanol evaporator and then enters the gas mixer to be mixed with oxygen; the mixed gas is preheated to the reaction temperature by a preheater and then enters an oxidation reactor for methanol oxidation reaction to obtain formaldehyde gas; the formaldehyde gas and other gas impurities then enter a water absorption tower, the formaldehyde gas is absorbed by water to obtain a high-concentration formaldehyde water solution, and the impurity gas is discharged from the top of the absorption tower.
5. A reactive distillation process for the synthesis of polymethoxy dimethyl ether according to claim 2 or 3, wherein: the methylal preparation working section comprises a methylal reaction rectifying tower, part of formaldehyde aqueous solution and methanol in the formaldehyde preparation working section are respectively added into the methylal reaction rectifying tower in a form of little excessive formaldehyde for reaction and separation, anhydrous methylal is extracted from the top of the methylal reaction rectifying tower, and water containing little formaldehyde is extracted from the tower bottom.
6. The reactive distillation process for the synthesis of polymethoxy dimethyl ether according to claim 2, wherein: the formaldehyde polymerization working section comprises a formaldehyde polymerization rectifying tower, steam permeation equipment and a trioxymethylene refining tower, wherein formaldehyde aqueous solution extracted from the formaldehyde preparation working section enters the formaldehyde polymerization rectifying tower to carry out polymerization reaction to generate trioxymethylene, a mixture of the trioxymethylene, formaldehyde and water is separated by the formaldehyde polymerization rectifying tower and then partially extracted from the tower top in a gas phase form, a part of liquid phase flows back, water which does not participate in reaction is separated by the formaldehyde polymerization rectifying tower and then extracted from the tower bottom, a gas phase mixture of the trioxymethylene, formaldehyde and water extracted from the tower top enters the steam permeation equipment to carry out membrane separation, water phase enters the permeation side of the steam permeation equipment to be extracted, a mixed phase of the trioxymethylene, formaldehyde and trace water is extracted by the steam permeation equipment to enter the trioxymethylene refining tower, anhydrous trioxymethylene is extracted from the tower top by the separation of the trioxymethylene rectifying tower, and a liquid phase mixture of the trioxymethylene, the formaldehyde and the water is then enters the steam permeation equipment to carry out secondary separation.
7. A reactive distillation process for the synthesis of polymethoxy dimethyl ether as claimed in claim 3, wherein: the gas-phase formaldehyde preparation working section comprises a formaldehyde aqueous solution evaporator, a vapor permeation device and an adsorption device which are sequentially connected, part of formaldehyde aqueous solution generated by an absorption tower in the formaldehyde preparation working section enters the gas-phase formaldehyde preparation working section, enters the vapor permeation device to remove water vapor in a mixed gas phase after being changed into a gas phase by the formaldehyde aqueous solution evaporator, and then enters the adsorption device to absorb and remove residual water vapor in the mixed gas phase to obtain anhydrous gas-phase formaldehyde.
CN201910307875.9A 2019-04-17 2019-04-17 Reactive distillation process device and method for synthesizing polymethoxy dimethyl ether Active CN110078600B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201910307875.9A CN110078600B (en) 2019-04-17 2019-04-17 Reactive distillation process device and method for synthesizing polymethoxy dimethyl ether

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201910307875.9A CN110078600B (en) 2019-04-17 2019-04-17 Reactive distillation process device and method for synthesizing polymethoxy dimethyl ether

Publications (2)

Publication Number Publication Date
CN110078600A CN110078600A (en) 2019-08-02
CN110078600B true CN110078600B (en) 2023-06-20

Family

ID=67415264

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201910307875.9A Active CN110078600B (en) 2019-04-17 2019-04-17 Reactive distillation process device and method for synthesizing polymethoxy dimethyl ether

Country Status (1)

Country Link
CN (1) CN110078600B (en)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110559678B (en) * 2019-10-21 2024-02-27 无锡赫利邦化工科技有限公司 Rectifying tower for synthesizing and separating polymethoxy dimethyl ether and application method thereof
CN111153776B (en) * 2020-02-14 2022-12-16 四川纬邦亿科技有限公司 DMMn production process and device
CN113929550B (en) * 2020-06-29 2023-12-08 中国石油化工股份有限公司 Mixed carbon four superposition reaction method and device
CN112299963B (en) * 2020-11-20 2022-01-07 清华大学 Method for continuously producing polymethoxy dimethyl ether
CN112898134B (en) * 2021-04-05 2023-09-12 山东辰信新能源有限公司 Dehydration and catalytic synthesis method and device for polymethoxy dimethyl ether

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104003855A (en) * 2014-05-21 2014-08-27 上海盘马化工工程技术有限公司 System for continuously preparing polymethoxy dimethyl ether by using methanol as initial reaction raw material
CN104058940A (en) * 2014-06-30 2014-09-24 西安市尚华科技开发有限责任公司 Method for synthesizing PODE through condensation, oxidation, polycondensation and etherification of methyl alcohol
CN104355973A (en) * 2014-11-01 2015-02-18 西安市尚华科技开发有限责任公司 Method for preparing polymethoxy dimethyl ether through reaction and rectification of fixed bed
CN104447237A (en) * 2013-09-24 2015-03-25 中国石油化工股份有限公司 Process method for preparing polyformaldehyde dimethyl ether from methanol
CN106256822A (en) * 2016-09-19 2016-12-28 江苏永大化工设备有限公司 Methanol is through condensation, oxidation, polycondensation, the method for process synthesizing triformol
CN106800500A (en) * 2017-01-17 2017-06-06 凯瑞环保科技股份有限公司 A kind of process for preparing polymethoxy dimethyl ether
CN206337194U (en) * 2016-12-22 2017-07-18 淄博津昌助燃材料科技有限公司 A kind of reaction unit in polymethoxy dimethyl ether production
CN206337198U (en) * 2016-12-22 2017-07-18 淄博津昌助燃材料科技有限公司 A kind of process units for producing polymethoxy dimethyl ether
CN108383696A (en) * 2018-04-24 2018-08-10 中国科学院成都有机化学有限公司 The method for preparing polymethoxy dimethyl ether

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104447237A (en) * 2013-09-24 2015-03-25 中国石油化工股份有限公司 Process method for preparing polyformaldehyde dimethyl ether from methanol
CN104003855A (en) * 2014-05-21 2014-08-27 上海盘马化工工程技术有限公司 System for continuously preparing polymethoxy dimethyl ether by using methanol as initial reaction raw material
CN104058940A (en) * 2014-06-30 2014-09-24 西安市尚华科技开发有限责任公司 Method for synthesizing PODE through condensation, oxidation, polycondensation and etherification of methyl alcohol
CN104355973A (en) * 2014-11-01 2015-02-18 西安市尚华科技开发有限责任公司 Method for preparing polymethoxy dimethyl ether through reaction and rectification of fixed bed
CN106256822A (en) * 2016-09-19 2016-12-28 江苏永大化工设备有限公司 Methanol is through condensation, oxidation, polycondensation, the method for process synthesizing triformol
CN206337194U (en) * 2016-12-22 2017-07-18 淄博津昌助燃材料科技有限公司 A kind of reaction unit in polymethoxy dimethyl ether production
CN206337198U (en) * 2016-12-22 2017-07-18 淄博津昌助燃材料科技有限公司 A kind of process units for producing polymethoxy dimethyl ether
CN106800500A (en) * 2017-01-17 2017-06-06 凯瑞环保科技股份有限公司 A kind of process for preparing polymethoxy dimethyl ether
CN108383696A (en) * 2018-04-24 2018-08-10 中国科学院成都有机化学有限公司 The method for preparing polymethoxy dimethyl ether

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
钟子太 ; 刘红 ; .聚甲氧基二甲醚工艺技术.氮肥技术.2016,(06),第38-41页. *

Also Published As

Publication number Publication date
CN110078600A (en) 2019-08-02

Similar Documents

Publication Publication Date Title
CN110078600B (en) Reactive distillation process device and method for synthesizing polymethoxy dimethyl ether
CN110078599B (en) Reactive distillation process method and device for synthesizing DMMn (dimethyl formamide) from methanol and high-concentration formaldehyde
CN110090464A (en) Partition wall reactive distillation method and device for polymethoxy dimethyl ether synthesis
CN106588589A (en) Purification method for polyoxymethylene dimethyl ether(PODE)
CN110156575B (en) Reactive distillation-vapor permeation coupling process for polymethoxy dimethyl ether synthesis
CN111978161A (en) Preparation process for preparing polymethoxy dimethyl ether by using methanol as raw material
WO2022095307A1 (en) Process and device for preparing trioxymethylene from methanol
US20030040637A1 (en) Process for the epoxidation of olefins
CN110423197A (en) A kind of device and method using low concentration ethylene glycol production glycol acetate
CN108218678B (en) Method and device for separating and refining polymethoxy dimethyl ether
CN110437044B (en) Method and device for preparing polymethoxy dimethyl ether
CN110078598B (en) Multi-stage reactive distillation synthesis process method and device for polymethoxy dimethyl ether
CN114984866B (en) System and method for preparing dimethyl maleate
CN115531901A (en) Reactor for synthesizing polymethoxy dimethyl ether by taking dimer as main raw material
CN212982838U (en) Device for preparing polymethoxy dimethyl ether from methanol
CN210237497U (en) Reactive distillation process device for synthesizing polymethoxy dimethyl ether
CN210078876U (en) A partition wall reaction rectifier unit for gathering methoxy dimethyl ether is synthetic
CN218485985U (en) Preparation device of polymethoxy dimethyl ether DMMn system
CN210229171U (en) Reaction rectification process unit for synthesizing DMMn from methanol and high-concentration formaldehyde
CN110156747B (en) Separation wall reaction rectification production process method and device for trioxymethylene
CN1356301A (en) External coupler of rectifying reaction for preparing cyclohexane by catalyst hydrogenation of benzene and its synthesizing process
US20230278943A1 (en) Method for producing polyoxymethylene dimethyl ethers
CN214193104U (en) Device for preparing trioxymethylene from methanol
CN112299963B (en) Method for continuously producing polymethoxy dimethyl ether
CN220531544U (en) Device and system for producing polymethoxy dimethyl ether by utilizing polyoxymethylene production waste material

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant