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210 results about "Reactive distillation" patented technology

Reactive distillation is a process where the chemical reactor is also the still. Separation of the product from the reaction mixture does not need a separate distillation step, which saves energy (for heating) and materials. This technique can be useful for equilibrium-limited reactions such as esterification and ester hydrolysis reactions. Conversion can be increased beyond what is expected by the equilibrium due to the continuous removal of reaction products from the reactive zone. This approach can also reduce capital and investment costs. Typically, reactive distillation equipment comprises a reactive column, with the feed input, with directly attached stripping and enriching columns with the outputs.

Low-energy-consumption tetramethyl ammonium bicarbonate preparation process

The invention provides a low-energy-consumption preparation process of tetramethylammonium bicarbonate, and relates to the technical field of chemical synthesis. The preparation process comprises the following steps: inputting trimethylamine, dimethyl carbonate and a solvent methanol into a reactive distillation tower, carrying out a quaternization reaction to generate methyl carbonate tetramethylammonium, and carrying out a hydrolysis reaction on a first liquid phase obtained by rectification and water vapor to generate TMAB; the reacted material is input into a methanol removal tower for rectification, an obtained second gas phase is heated and pressurized, one part of the second gas phase is input into a subsequent methanol recovery tower, the other part of the second gas phase exchanges heat with water to generate steam, the steam is input into a tower kettle of the methanol removal tower, and high-purity methanol is extracted from the side of the methanol recovery tower. The number of reaction equipment is reduced, and the energy utilization rate is increased; the steam grade is improved by utilizing a heat pump technology, and steam latent heat is integrated between the methanol removal tower and the methanol recovery tower through thermal coupling, so that the overall process energy consumption is remarkably reduced while the product quality is ensured.
Owner:TIANJIN CHENLI ENG DESIGN CO LTD

System and method for preparing carbonic ester

The invention provides a system and method for preparing carbonic ester, and the system comprises a pre-reactor which is used for the pre-reaction of carbonic ester and alcohol; the suspension type reaction rectifying tower comprises a rectifying section, a reaction section and a stripping section and is used for continuously reacting the pre-reacted material in the reaction section after rectifying the pre-reacted material through the rectifying section, and the heterogeneous solid catalyst reacts in the reaction section in a suspension manner; the suspended reactive distillation tower is provided with a gas ascending pipeline, and the gas ascending pipeline is communicated with a gas outlet in the top of the stripping section and a gas phase space in the top of the reaction section and is used for separating gas phase ascending of the stripping section. The system disclosed by the invention is simple in structure, effectively solves the problems of complex loading and unloading of a catalyst, damage of the catalyst and large discharge amount of three wastes in existing heterogeneous reactive distillation, and can be applied to industrial production; the method is especially suitable for production of chain carbonate or linear carbonate generated by esterification reaction of cyclic carbonate and alcohol.
Owner:CHINA PETROLEUM & CHEMICAL CORP +1

Composite catalyst for synthesizing polyester as well as preparation method and application of composite catalyst

InactiveCN120209283APolyesterPolymer science
The invention discloses a composite catalyst for synthesizing polyester as well as a preparation method and application thereof, and relates to the technical field of catalysts. According to the technical scheme, the method comprises the following steps: in a nitrogen atmosphere, mixing a first metal catalyst, a slow release agent and an organic solvent, reacting at 130-150 DEG C for 1-3 hours, and distilling to separate by-products to obtain a reaction product; and adding a second metal catalyst and an activity regulator into the reaction product, reacting at 130-150 DEG C for 1-3 hours, and distilling to separate by-products, thereby obtaining the composite catalyst for synthesizing polyester. The composite catalyst for synthesizing polyester has good compatibility with water, ethylene glycol or PET oligomer, and has the characteristic of controllable catalytic activity compared with a traditional titanium catalyst. When the composite catalyst is applied to synthesis of polyester, the composite catalyst has the characteristics of few side reactions and fast ester exchange reaction, and the obtained polyester product has the advantages of high intrinsic viscosity and good product hue.
Owner:FUHAI (DONGYING) TECHNICAL SERVICES CO LTD

Method for preparing tetracyclododecene through reactive distillation

The invention provides a method for preparing tetracyclododecene in a reactive distillation device by taking C9 fraction and norbornene as raw materials. The method comprises the following steps: mixing the C9 fraction and the norbornene in a mixer and reacting in the reactive distillation device; the reacted material is directly rectified in a reaction rectification device, residual C9 fraction and norbornene in the reaction are obtained at the tower top, and a crude tetracyclododecene product is obtained in the reaction kettle; and separating high-boiling-point components from the crude tetracyclododecene product in the reaction kettle section of the rectifying tower in the reactive distillation device in a third rectifying tower to obtain the high-purity tetracyclododecene product. According to the invention, the reaction rectification device is used, and the reactor is combined with the rectification tower, so that the reaction product can be directly and preliminarily separated to obtain a light component mainly containing norbornene and a heavy component containing tetracyclododecene, the equipment cost can be saved, the energy consumption can be reduced, and the rectification effect can be improved; meanwhile, the C9 fraction is used as a raw material, and downstream application of the C9 fraction is expanded.
Owner:CHINA PETROLEUM & CHEMICAL CORP +1

Method for efficiently preparing hydroxylamine hydrochloride

PendingCN120440851AHydroxylamineBenzoyl peroxideHydroxylamine
The invention relates to a method for efficiently preparing hydroxylamine hydrochloride. The method comprises the following steps: mixing a diacetylmonoxime solution and a hydrochloric acid solution, pretreating through a pressurized nano-bubble fluidized bed, and carrying out reaction distillation under heating and pressurizing; after the reaction is finished, cooling reaction liquid, performing primary filtration and suction filtration through cross-flow filtration equipment, and collecting hydroxylamine hydrochloride crystals; and washing the crystal with absolute ethyl alcohol, recovering ethyl alcohol through cross-flow filtration equipment, and finally freeze-drying to obtain the high-purity hydroxylamine hydrochloride. The preparation method comprises the following steps: stirring quinoline-8-yl acrylate, tributyltin acrylate, 4-vinyl benzocyclobutene, ethanol and benzoyl peroxide to obtain a mixed solution; immersing the PTFE membrane subjected to low-temperature plasma pretreatment into the mixed solution, and then carrying out ultrasonic cleaning and vacuum drying to obtain a polymer modified PTFE membrane; the hydroxylamine hydrochloride prepared by the method disclosed by the invention has relatively high purity and yield, and meanwhile, the content of heavy metal ions and the content of water are effectively reduced.
Owner:ZHEJIANG JINHUA NEW MATERIALS

Production system for producing silane gas by combining fixed bed reactor and reactive distillation column

The utility model provides a production system for producing silane gas by combining a fixed bed reactor and a reactive distillation tower, and relates to the technical field of silane gas production. The production system for producing the silane gas by combining the fixed bed reactor and the reactive distillation column comprises the fixed bed reactor which is provided with a DCS (Distributed Control System) feed port and can be used for performing DCS disproportionation reaction to prepare a one-step disproportionated product; the primary separation tower is communicated with the fixed bed reactor and can be used for rectifying and separating a one-step disproportionated product, crude SiH4 is extracted from the tower top of the primary separation tower, and a chlorosilane mixture is extracted from the tower kettle of the primary separation tower; the second-stage separation tower is communicated with the first-stage separation tower and can be used for rectifying and separating the chlorosilane mixture, and a TCS mixture is extracted from a tower kettle of the second-stage separation tower; and the reactive distillation tower is communicated with the second-stage separation tower, is provided with a TCS feed port, can perform a TCS disproportionation reaction and rectify and separate a product, and crude SiH4 is extracted from the tower top of the reactive distillation tower. According to the utility model, not only can the conversion rate of the DCS total reaction process be improved, but also the silane gas productivity can be improved, and the operation energy consumption can be reduced.
Owner:四川永祥能源科技有限公司

Process for producing polyethylene glycol by coupling reactive distillation separation ternary water-containing azeotropic system

The invention relates to a process for producing polyethylene glycol by coupling a reactive distillation separation ternary water-containing azeotropic system. According to the process, excessive ethylene oxide is introduced into a ternary water-containing azeotropic system, water in the system is completely converted into polyethylene glycol to be extracted as a by-product, and the excessive ethylene oxide and residual organic components of the system are separated through a common rectification technology. According to the invention, chemical reaction and rectification separation are coupled to be carried out in one tower, reaction and separation are realized at the same time, and heat released by the reaction can reduce the thermal load of the reboiler.
Owner:HEBEI UNIV OF TECH

Reaction rectifying tower for preparing ethylene glycol

The invention relates to the field of rectifying towers, and discloses a reaction rectifying tower for ethylene glycol preparation, which comprises a rectifying tower body, a wave tower plate, a discharge shell, a turnover piece, a scraping mechanism, a rolling suction mechanism, an ejection mechanism, a guide return piece, a draw-off pump and a communication shell, the wave tower plate is mounted in the rectifying tower body, the middle part of the wave tower plate is divided into two sub-wave tower plates by the discharging shell, and the two sub-wave tower plates are connected through the communicating shell so as to guide an ethylene glycol solution; the overturning piece is arranged on the discharging shell, and the guiding return piece is connected with the scraping mechanism. The scraping mechanism is connected with the driving part, and when the driving part drives the scraping mechanism to scrape the wave tower plate, steam extraction and drainage are synchronously carried out. The driving piece and the scraping mechanism work cooperatively, non-stop cleaning is achieved, the sleeve plate one-way air inlet valve is matched with the scraping plate exhaust hole to purge impurities and strengthen mass transfer, the magnetic block rotates to attract the ejection mechanism to eject the pipe to clear blockage, and it is guaranteed that steam passes through.
Owner:HONGMAO (SHENZHEN) TECHNOLOGY CO LTD

Resource utilization method of 1, 1, 2-trichloroethane waste liquid

The invention discloses a resource utilization method of 1, 1, 2-trichloroethane waste liquid, which comprises the following steps: 1) feeding the 1, 1, 2-trichloroethane waste liquid into a scraper device to remove heavy components, and extracting gas-phase light components from the top; (2) condensing the gas-phase light component, feeding into a chlorination reactor, and carrying out chlorination reaction; and 3) carrying out reactive distillation on the material at the outlet of the chlorination reactor to remove light components and heavy components to obtain 1, 1, 2-trichloroethane. According to the method, on one hand, impurities which influence the purity of 1, 1, 2-trichloroethane and are difficult to separate react with chlorine under specific conditions to generate heavier components, and on the other hand, it is ensured that light components cannot be chlorinated into the impurities which are difficult to separate, and 1, 1, 2-trichloroethane with the purity being 99% or above can be recycled; on the other hand, 5-20 wt% of 1, 1, 2-trichloroethane is additionally generated in the reactive distillation process, waste liquid recycling is achieved, and the method has the advantages of being simple in technological process, low in energy consumption and high in product yield.
Owner:WANHUA CHEM GRP CO LTD

Synthesis process of battery grade ethyl methyl carbonate / diethyl carbonate

The invention discloses a battery grade methyl ethyl carbonate / diethyl carbonate synthesis process, which adopts a transesterification method, and dimethyl carbonate (DMC) and ethanol react under the catalysis of sodium methoxide to generate methyl ethyl carbonate (EMC), diethyl carbonate (DEC) and byproduct methanol. High-purity battery-grade EMC and DEC products are obtained through the steps of reactive distillation, azeotrope separation, methanol refining, catalyst carbonization removal, crude EMC / DEC separation, EMC light component removal, industrial-grade EMC refining, battery-grade EMC refining, industrial-grade DEC refining, battery-grade DEC refining and the like. The method has the advantages of simple process flow, low energy consumption, easiness in product separation, high product purity and the like, and is suitable for large-scale production of battery-grade carbonate products.
Owner:CHINA CONSTRUCTION INDUSTRIAL & ENERGY ENGINEERING GROUP CO LTD +1

Reactive rectification device and method for automatically separating phases and refluxing to reaction section

The invention relates to a reactive distillation device and method for automatically separating phases and refluxing to a reaction section, and belongs to the technical field of chemical reaction and separation coupling. The reactive distillation tower (1) sequentially comprises a distillation section (11), a reaction section (12) and a stripping section (13) from top to bottom, the tower bottom of the reactive distillation tower (1) is connected with a heater (2), the tower top of the reactive distillation tower (1) is sequentially connected with a tower top condenser (3) and an automatic phase splitter (4) through pipelines, materials are condensed by the tower top condenser (3) to form a water phase and an oil phase which are not completely mutually soluble, and the water phase and the oil phase are separated from each other. After automatic phase splitting in the automatic phase splitter (4), the water phase automatically and continuously flows into a water phase collecting tank (5) from the upper part of the automatic phase splitter (4), the oil phase automatically and continuously flows out from the lower part of the automatic phase splitter (4), one part of the oil phase returns to the rectifying section (11) through the reflux ratio controller (6), and the other part of the oil phase returns to the rectifying section (11) through the reflux ratio controller (6); one part of the gas automatically flows back into the reaction section (12) by virtue of the liquid level to continuously react, so that a high-purity product is obtained in the tower kettle. The device is simple in structure and control method and convenient to operate, unreacted raw materials are rectified and then automatically flow back into the reaction section in a split-phase mode to participate in the reaction again, the raw material utilization rate is increased, the reaction conversion rate is high, and a water phase and an oil phase can be automatically extracted in a split-phase mode and flow back.
Owner:TIANJIN GOLDEN EAGLE TECH

A uv-3 ultraviolet absorber and a method for preparing the same

PendingCN122325354AXylyleneChemical synthesis
This application relates to a UV-3 ultraviolet absorber and its preparation method, belonging to the field of chemical synthesis technology. The preparation method employs a one-pot process, in which benzocaine reacts with triethyl orthoformate in xylene solvent. This step utilizes reactive distillation coupling control, continuously removing the generated alcohol distillate through a distillation separation device to promote reaction equilibrium shift, obtaining a xylene solution of the intermediate NET. Subsequently, the solution is heated to a reaction temperature of 135–145°C, and benzyl chloride is added dropwise for N-alkylation, while a tail gas absorption device absorbs byproduct gases. The reaction slurry is then cooled for crystallization, solid-liquid separation, and drying to obtain the UV-3 product. This invention simplifies the production process through a one-pot process, avoids the use of toxic DMF solvent, and solves the technical problem of raw material residues leading to subsequent side reactions in the one-pot process through reactive distillation coupling control, resulting in a final product with high purity and high yield.
Owner:CHANGZHOU YONGHE FINE CHEM

Method for preparing 6N and above high-purity Nb2O5 from niobium oxalate precursor

The invention discloses a method for preparing 6N and above high-purity Nb2O5 by using a niobium oxalate precursor, belongs to the technical field of niobium pentoxide preparation, and solves the problems of low purity and high impurity content of Nb2O5 prepared by the existing method. The method comprises the following steps: mixing niobium oxalate with high-purity water to obtain a mixed solution; performing cold crystallization purification; separating niobium oxalate crystals from the mother liquor, washing and drying; the method comprises the following steps: putting niobium oxalate crystals into a crucible, putting the crucible into a vacuum reaction distillation furnace, sealing a system, vacuumizing to below 1Pa, carrying out inert gas replacement, and then carrying out stage heating and heat preservation; cooling to 800-900 DEG C, introducing high-purity oxygen into the system, and carrying out oxidation stabilization treatment at a constant temperature; after treatment, continuously cooling to 200 DEG C or below, and then naturally cooling to room temperature to obtain a high-purity Nb2O5 product. The Nb2O5 product prepared by the method disclosed by the invention is high in purity and low in impurity content.
Owner:CNMC NINGXIA ORIENT GRP +1

Device and process for preparing isopropanol through reactive distillation

The invention relates to the technical field of isopropanol preparation, in particular to a device and a process for preparing isopropanol through reactive distillation. Comprising refining equipment, a preheater, a hydrogen filter, a hydrogen compressor, a buffer tank, a hydrogen heat exchanger, a hydrogenation reactor, a gas-liquid separator and a recovery tower, the hydrogenation reactor comprises a tower body; the tower body comprises an upper tower body and a lower tower body; a gas inlet is formed in the upper end of the upper tower body; by arranging the material changing box, the catalytic plate can be pre-filled in the material changing box, specifically, before the reactor is shut down, an operator pre-loads a new catalytic plate into the material changing box and completes nitrogen replacement so as to thoroughly eliminate oxygen in the material changing box, and therefore during replacement, the replacement efficiency is greatly improved. Compared with the prior art, an operator can directly push the pre-filled catalytic plate into the tower body for replacement without replacing hydrogen in the tower body after shutdown, so that the hydrogen replacement steps are reduced, the shutdown time of equipment is remarkably shortened, and the production efficiency of isopropanol is improved.
Owner:JIANGSU XINHUA CHEM +1

Diphenyl carbonate reactive distillation system capable of realizing side-draw

The diphenyl carbonate reactive distillation system comprises a reactive distillation tower, a reflux pipeline, a tower top reflux tank, a first condenser, a methanol recovery system, a reflux pump, a side extraction pipeline, a side extraction pump, a buffer tank, a discharge pipeline, a tower bottom pump and a flash tank, a tower top liquid material of the reactive distillation tower enters a tower top reflux tank through a reflux pipeline, and a gas material enters a methanol recovery system after being condensed by a first condenser; controlling the reflux ratio, and refluxing the material in the tower top reflux tank; the reactive distillation column is provided with a height-adjustable side line extraction opening for extracting by-products such as anisole; and separating the reaction organisms through a flash tank to obtain diphenyl carbonate. The device integrates chemical reaction and rectification separation, methanol is separated from a material refluxed at the top of the tower, by-products such as anisole are extracted from a side line, the thermodynamic equilibrium of the reaction is broken, and the reaction is pushed to proceed in the positive direction, so that the conversion rate is increased, and meanwhile, a plurality of by-products are obtained; and the side line extraction position is adjustable, safe and convenient.
Owner:HAINAN IND RES INST

Process for the production of 4-methyl-2-pentanone

PendingCN122325302APtru catalystReboiler
This invention discloses a method for producing 4-methyl-2-pentanone, which is implemented using a 4-methyl-2-pentanone production apparatus. The apparatus includes a reactive distillation column, a condenser connected to the top of the reactive distillation column, and a reboiler connected to the bottom of the column. The reactive distillation column has a rectification section, a reaction section, and a stripping section arranged sequentially from top to bottom. During operation, a catalyst is placed in the reaction section, and 4-methyl-2-pentanol is introduced into the reaction section. The temperature of the reaction section is controlled at 180–280°C. The gas phase produced by the reaction is condensed by the condenser to produce 4-methyl-2-pentanone. This production method features high conversion rate, stable product quality, and low energy consumption.
Owner:SENNICS CO LTD

Process and system for converting crude oil to petrochemical products

A process for treating a crude oil feedstock includes: introducing a crude oil stream into a reactive distillation unit to remove Conrason carbon residues and metals from the crude oil stream and produce a distillate stream having an average boiling point distribution that is less than the average boiling point distribution of the crude oil stream; and feeding the distillate stream in gaseous form, in a continuous manner and without further treatment, to a catalytic cracking reactor operating at a temperature of 300 DEG C to 800 DEG C, the catalytic cracking reactor having a cracking catalyst arranged therein, the cracking catalyst cracking the distillate stream, to form a petrochemical product stream comprising light olefins and BTX.
Owner:SAUDI ARABIAN OIL CO +2

Device for one-way preparation of electronic-grade silane gas in particle silicon manufacturing process

The utility model discloses a device for one-way preparation of electronic grade silane gas in a particle silicon process, the device comprises a preheater, a light component removal unit, a silane reaction unit, a condensation unit, a separation unit and a gasification purification unit which are connected in sequence, and the silane reaction unit comprises more than two silane reaction towers which are arranged in parallel. According to the utility model, more than two silane reaction towers are arranged in the silane reaction unit in parallel, so that trichlorosilane is converted into silane at one time after being sequentially subjected to the steps of preheating, light component removal, reactive distillation, condensation heat exchange, separation and gasification purification; the conversion per pass can be improved, the material condensation and reboiling processes are reduced, the energy consumption is reduced, and the production process cost is reduced.
Owner:内蒙古鑫元硅材料科技有限公司

Continuous production system and continuous production method of diethyl maleate

The invention discloses a continuous production system for diethyl maleate. The continuous production system comprises a reactive distillation tower, a benzene-water separation tank, a vacuum distillation tower, a benzene removal tower and an ethanol distillation tower. The device comprises the vacuum rectifying tower, the debenzolization tower and the ethanol rectifying tower, and the vacuum rectifying tower is used for purifying tower kettle materials in the reaction rectifying tower, so that the product purity is improved; the debenzolization tower is used for removing a reboiling agent benzene in a water-phase material in the benzene-water separation tank, then the reboiling agent benzene is circulated to the benzene-water separation tank for reuse, the ethanol rectifying tower is used for separating ethanol and water from a material in a tower kettle of the debenzolization tower, and the ethanol is recycled, so that the utilization rate of raw materials is effectively improved. The invention further discloses a continuous production method of the diethyl maleate, a vacuum rectification technology and a normal-pressure double-tower rectification technology are adopted, the purity of the obtained diethyl maleate product can reach 99.9 wt% or above, the product purity is high, reboiling agents benzene and ethyl alcohol can be effectively recycled, and the utilization rate of raw materials is effectively increased.
Owner:SHANGHAI DAOZUAN MASCH EQUIP CO LTD

Preparation method of N, N-diisopropylethylamine based on liquid-phase compression synthesis process

The invention provides a preparation method of N, N-diisopropylethylamine based on a liquid-phase compression synthesis process, which comprises the following steps: mixing ethanol with hydrobromic acid with specified concentration, and carrying out reactive distillation treatment in the presence of a phase transfer catalyst to generate bromoethane; p-bromoethane and diisopropylamine are subjected to a liquid phase addition and compression combination reaction, and a reaction mixture is obtained; and sequentially neutralizing, distilling, condensing and filtering the reaction mixture to obtain the N, N-diisopropylethylamine, so as to solve the problems that the existing preparation method of the N, N-diisopropylethylamine is high in energy consumption, high in operation risk, large in pollutant discharge amount, low in by-product resource utilization rate, low in cost and the like. The safety is poor; the energy efficiency is low; and by-products cannot be recycled.
Owner:NINGXIA HAITAI NEW MATERIAL CO LTD

Improved process for depolymerization of polyethylene terephthalate

The invention relates to a method for depolymerizing polyethylene terephthalate (= "PET"), wherein PET is reacted in a mixture containing ethylene glycol and MAOR to form bis (2-hydroxyethyl) terephthalate (= "BHET"; cAS No.: 959-26-2) in which MA is an alkali metal selected from the group consisting of sodium, potassium, lithium, and in which R is an alkyl group having 1 to 6 carbon atoms. The MAOR is obtained by reactive distillation. The method according to the invention is characterized in that the proportion of unwanted cleavage products mono (2-hydroxyethyl) terephthalate (= "MHET") and terephthalate (= "TS") is particularly low relative to the proportion of BHET. Thus, the process according to the invention provides a high yield of BHET, which can be directly used in regenerative PET production. The invention also relates to a process for recovering PET in which BHET obtained in the PET depolymerization process is re-polymerized to form PET, optionally after further cleaning.
Owner:EVONIK OPERATIONS GMBH

Preparation method of ethyl tert-butyl ether

The invention provides an ethyl tert-butyl ether preparation method, which comprises: carrying out at least two-stage etherification reaction on a C4 raw material and ethanol to obtain a pre-product; carrying out reactive distillation on the pre-product, wherein the reactive distillation comprises stripping treatment and reactive distillation treatment; the pre-product is subjected to stripping treatment, an ethyl tert-butyl ether product is extracted, and a C4 and ethanol mixture obtained through separation is subjected to reactive distillation treatment; ethyl tert-butyl ether obtained through reactive distillation treatment is returned for stripping treatment, and C4 and ethanol obtained through reactive distillation separation are subjected to ethanol recovery treatment. According to the preparation method, stripping of reactive distillation and reactive distillation are carried out separately, and ethyl tert-butyl ether in a pre-product and unreacted C4 and ethanol are separated before reactive distillation, so that the raw material conversion rate of the reactive distillation step is greatly improved, and the overall conversion rate of isobutene is further improved; and meanwhile, the purity of the ethyl tert-butyl ether product extracted by reaction distillation is improved.
Owner:KAIRUI ENVIRONMENTAL PROTECTION TECH

Low-energy-consumption tetramethyl ammonium bicarbonate preparation device

The utility model provides a tetramethyl ammonium bicarbonate preparation device with low energy consumption, which comprises a reactive distillation tower, a static mixer, a methanol removal tower and a methanol recovery tower, a gas phase discharge port of the methanol removal tower is connected with an inlet of a steam compressor, a first branch connected with an outlet of the steam compressor is connected with a gas inlet of the methanol recovery tower, and a second branch connected with an outlet of the steam compressor is connected with a gas outlet of the methanol recovery tower. A second branch connected with an outlet of the steam compressor is connected with the first return tank through a heating medium channel of the steam generator; a third branch connected with an outlet of the first reflux tank is connected with a feed port of the methanol recovery tower, and a fourth branch connected with the outlet of the first reflux tank is connected with a tower kettle of the methanol removal tower; after pure water exchanges heat through a refrigerant channel of the steam generator, steam is output, and the steam is input into a tower kettle of the methanol removal tower through a pipeline; and the methanol recovery tower is provided with a side extraction opening for extracting high-purity methanol. The device disclosed by the utility model is low in operation energy consumption, low in equipment investment and high in raw material utilization rate, and can be used for continuously preparing high-purity TMAB and recovering to obtain a high-purity methanol product.
Owner:TIANJIN CHENLI ENG DESIGN CO LTD

Improved process for producing alkali metal methoxides

PendingUS20260193158A1Methanol waterPhysical chemistry
The present invention relates to a process for preparing at least one alkali metal methoxide by reactive distillation in at least one reaction column. At the lower end of the reaction column(s), the respective alkali metal methoxide dissolved in methanol is withdrawn. The methanol / water mixture obtained at the top of the reaction column(s) is separated by distillation in a rectification column.The vapours obtained at the upper end of the rectification column are compressed in at least two stages and the energy of the vapours compressed in each case is advantageously transferred to bottoms and side streams of the rectification column. This allows particularly efficient use of the energy of the compressed vapours in the process according to the invention. In addition, the energy in the product stream of alkali metal methoxide which is obtained at the lower end of the reaction column(s) is advantageously transferred to the vapour streams from the rectification column, especially before these vapours are subjected to compression.The energy from the compressed vapour may additionally be used for operation of the reaction column(s) or for operation of a reaction column in which a process for transalcoholization of alkali metal alkoxides is performed.
Owner:EVONIK OPERATIONS GMBH

Catalytic reaction rectification unit, apparatus and method

This invention discloses a catalytic reactive distillation unit, apparatus, and method. The catalytic reactive distillation unit includes: a reaction mass transfer channel, the upper end of which receives low-temperature liquid-phase reactants flowing downwards, and the lower end of which receives high-temperature gas phase flowing upwards; the reaction mass transfer channel contains a catalyst layer and a packing layer, with the catalyst layer positioned above the packing layer, and a first space between them; and a rising gas bypass, located outside the reaction mass transfer channel and connected to the first space. The liquid-phase products after the catalytic reaction merge with the high-temperature gas phase in the packing layer and undergo gas-liquid mass transfer. The rising gas phase after mass transfer carries the light components from the liquid-phase products into the rising gas bypass, completing mass transfer separation. This invention, through the setting of the rising gas bypass, not only increases the gas phase flow rate and effectively reduces the pressure drop within the reaction mass transfer channel, but also effectively solves the space occupation problem of the equipment. This invention can clean the blockage of the catalyst filter without additional power and can realize online replacement of the catalyst and / or packing.
Owner:CHINA PETROLEUM & CHEMICAL CORP +1

Improved process for depolymerising polyethylene terephthalate

The present invention relates to a process for depolymerising polyethylene terephthalate (“PET”), in which method PET is reacted with sodium glycolate or potassium glycolate, which has been obtained by reactive distillation, to form a mixture M1 including Bis(2-hydroxyethyl) terephthalate (“BHET”). The process according to the invention is distinguished by the fact that BHET makes up a particularly high proportion of the decomposition products in the mixture M1. The process according to the invention thus provides a high yield of BHET that can be used directly for producing PET again. The present invention thus also relates to a process for recycling PET, in which the BHET obtained in the process for depolymerising PET is polymerised again to form PET, optionally after being further purified from M1.
Owner:EVONIK OPERATIONS GMBH

Method for preparing a reaction product, compositions including the reaction product, and uses of the reaction product

Disclosed is a process for preparing a reaction product, the process including adding 1-amino-2-propanol into a liquid form of formaldehyde to form an intermediate reaction mixture, wherein the molar ratio of formaldehyde to 1-amino-2-propanol is from 1.4:1 to less than 2:1, and subsequently subjecting the intermediate reaction mixture to reactive distillation to form the reaction product, wherein the predominant compound present in the reaction product is 3,3′-methylenebis[5-methyloxazolidine]. Compositions prepared according to the process are also disclosed.
Owner:THE LUBRIZOL CORP

Intelligent control system and intelligent control method for catalytic-free tert-butane production

This invention provides an intelligent control system and method for the production of tert-butane without catalytic reduction, belonging to the field of tert-butane production control. The intelligent control system includes a host computer and sensing and execution mechanisms electrically connected to the host computer. The sensing mechanisms include a TDLAS analyzer installed at the top outlet of the reactive distillation column, NIR analyzers installed at the tert-butanol inlet of the mixing preheater and the side outlet of the reactive distillation column, temperature sensors installed at the top, bottom, and side outlet of the reactive distillation column, flow meters installed at the feed inlet, top outlet, and reflux inlet of the reactive distillation column, and multiple pressure sensors spaced at equal intervals along the height of the reaction section. The execution mechanisms include electrically operated regulating valves installed at the feed inlet and reflux inlet of the reactive distillation column. The control system integrates multiple sensors and execution mechanisms, enabling closed-loop intelligent control of the entire process.
Owner:MAIQI CHEM CO LTD

Reactive distillation column and maintenance equipment thereof

The invention discloses a reactive distillation tower and maintenance equipment thereof, and belongs to the technical field of reactive distillation equipment. The device comprises a tower body, a flow dividing assembly is arranged on one side of the tower body and in the middle of the tower body, the flow dividing assembly comprises a flow dividing pipe, the bottom of the flow dividing pipe is fixedly connected with a flow dividing disc, the middle of the bottom of the flow dividing disc is fixedly connected with a lower flow dividing spray head, and the edge of the bottom of the flow dividing disc is fixedly connected with a plurality of side flow dividing spray heads. The side shunting nozzles are obliquely arranged towards the middle part of the shunting plate; according to the reactive distillation tower disclosed by the invention, the side shunting nozzles positioned on the outer side edges of the shunting assemblies are obliquely arranged towards the inner side, so that liquid flow sprayed by the side shunting nozzles can mutually impact liquid flow sprayed by the lower shunting nozzles in the side shunting nozzles, and the liquid flow cannot directly impact the inner wall of the tower body; therefore, the erosion loss speed of the anti-corrosion coating on the inner wall of the tower body is reduced, the service life of the reactive distillation tower is effectively prolonged, and the maintenance frequency is reduced.
Owner:HENAN RUIBAI NEW MATERIALS CO LTD

Method for controlling a reactive distillation column

A method for controlling a reactive distillation column for effecting a transalcoholisation reaction, comprising feeding a metal methoxide into the reactive distillation column via a side feed; feeding a reactant alcohol into a lower part of the reactive distillation column; withdrawing methanol from the top of the reactive distillation column; and withdrawing a solution of a product metal alkoxide in the reactant alcohol from the bottom of the reactive distillation column; wherein the method comprises a process control scheme selected from: Scheme A: establishing a signal S1 which is responsive to a temperature in the rectifying section disposed above the feed of the metal methoxide; and manipulating in response to the signal S1 the feed amount of the reactant alcohol; Scheme B: establishing a signal S1 which is responsive to a temperature in the rectifying section disposed above the feed of the metal methoxide; and manipulating in response to the signal S1 the heat supplied to the bottom of the reactive distillation column. The invention also relates to a method for controlling a reactive distillation column for effecting a transalcoholisation reaction, comprising feeding a metal methoxide into the reactive distillation column via a side feed; feeding a reactant alcohol into a lower part of the reactive distillation column; causing an auxiliary alcohol to be present in the reactive distillation column; and optionally replenishing the auxiliary alcohol via a side feed located above the feed of the reactant alcohol and below the top of the column; withdrawing methanol from the top of the reactive distillation column; and withdrawing a solution of a product metal alkoxide in the reactant alcohol from the bottom of the reactive distillation column; wherein the method comprises a process control scheme selected from: Scheme C: establishing a signal S2 which is responsive to a temperature at a point located between the feed of the metal methoxide and the bottom of the reactive distillation column; and manipulating in response to the signal S2 the feed amount of the reactant alcohol; Scheme D: establishing a signal S2 which is responsive to a temperature at a point located between the feed of the metal methoxide and the bottom of the reactive distillation column; and manipulating in response to the signal S2 the heat supplied to the bottom of the reactive distillation column. The methods of the invention allow for improved controlling of a reactive distillation column for effecting a transalcoholisation reaction.
Owner:BASF SE