175 results about "Dimethyl oxalate" patented technology

The invention discloses a device and a method for producing oxamide, and relates to the field of chemical production. The method for producing oxamide specifically comprises the following steps: mixing a methanol solution of liquid ammonia and a methanol solution of dimethyl oxalate, carrying out ammonolysis reaction, carrying out flash evaporation, filtration and drying on first slurry obtained after the reaction is finished to obtain solid oxamide, and refining a liquid phase obtained by solid-liquid separation of the first slurry to obtain a byproduct methanol, ammonia in the tail gas is washed and absorbed by dimethyl oxalate and then returns to a reaction system. In the oxamide production process, dimethyl oxalate reacts with ammonia gas in mixed gas generated in the reaction process, and the obtained product is continuously subjected to subsequent ammonolysis reaction, so that the utilization rate of reaction materials is increased; meanwhile, a condenser is not used for condensing ammonia gas and methanol and then separating alcohol and ammonia, so that condensing equipment and cooling water are saved, the production cost is reduced, and industrial production is facilitated.

The invention discloses a process and a device for producing oxamide, and relates to the field of chemical production. The invention provides a process for producing oxamide, which specifically comprises the following steps: mixing a methanol solution of liquid ammonia and a methanol solution of dimethyl oxalate, carrying out ammonolysis reaction, carrying out flash evaporation, filtration and drying on first slurry after the reaction is finished to obtain solid oxamide, and carrying out liquid phase refining to obtain a byproduct methanol, ammonia in the tail gas is washed and absorbed by dimethyl oxalate and then returns to a reaction system. The methanol solution of dimethyl oxalate is used for absorbing excessive ammonia in the reaction process, and the reaction product is continuously used for producing oxamide, so that methanol and ammonia can be thoroughly separated, the conversion rate of ammonia can be greatly improved, and the economical efficiency of the production process is improved; meanwhile, tail gas containing ammonia is not discharged, and the environmental protection property of the production process is improved.

The invention discloses an oxamide preparation tail gas treatment device which comprises a methanol absorption section, a methanol condensation section, an ammonia absorption section and an ammonia absorption raw material preparation section which are sequentially arranged from top to bottom, methanol in gas is absorbed by the methanol absorption section through desalted water, and ammonia in the gas is absorbed by the ammonia absorption section through a methanol solution of dimethyl oxalate. The method comprises the following steps: absorbing unreacted ammonia by using dimethyl oxalate, generating oxamide, returning the oxamide to an oxamide synthesis reactor, condensing methanol steam without ammonia so as to reduce methanol brought out by nitrogen, washing tail gas by using a circulating aqueous solution and desalted water, discharging the tail gas after reaching the standard, and feeding the aqueous solution containing methanol to a sewage treatment device to supplement a carbon source. According to the method, steam does not need to be consumed, only a small amount of cooling water or chilled water needs to be consumed, ammonia in the tail gas is absorbed through reaction of dimethyl oxalate needed in the oxamide production process and ammonia in the tail gas, then methanol in the tail gas is condensed and then returns to a reaction system, and therefore recycling of the ammonia and the methanol is achieved.

The invention discloses high-performance silver paste added with nano silver oxide and a preparation method of the high-performance silver paste. The high-performance silver paste comprises the following components: an organic carrier, glass powder, silver powder and an additive, the organic carrier comprises a volatile solvent and non-volatile resin; the non-volatile resin comprises ethyl cellulose, nitrocellulose, acrylic resin, polyamide wax resin and hydrogenated castor oil; the volatile solvent comprises texanol, diethylene glycol monobutyl ether, diethylene glycol monobutyl ether acetate, tributyl citrate, dimethyl oxalate and dimethyl silicone oil; the additive adopts nano silver oxide. The invention relates to the technical field of solar cells. Compared with silver powder, the nano silver oxide is smaller in particle size, large in specific surface area and low in tap density, the viscosity can be improved when the nano silver oxide is added into the paste, the height-width ratio of a printing grid line electrode can be improved, the shading area can be reduced, the current of a battery piece can be improved, and the photoelectric conversion efficiency of the battery piece can be improved.

The present invention discloses a device and method for producing oxalamide, and relates to the field of chemical production. The method for producing oxalamide provided by the present invention specifically comprises: mixing a methanol solution of liquid ammonia and a methanol solution of dimethyl oxalate to undergo an ammonolysis reaction, flashing, filtering, and drying the first slurry after the reaction to obtain solid oxalamide, refining the liquid phase obtained by solid-liquid separation of the first slurry to obtain byproduct methanol, and washing and absorbing ammonia in the tail gas with dimethyl oxalate and returning to the reaction system. In the process of oxalamide production, the present invention utilizes dimethyl oxalate to react with ammonia in the mixed gas generated during the reaction, and the obtained product continues to undergo subsequent ammonolysis reaction, thereby improving the utilization rate of the reaction materials; at the same time, a condenser is not used to condense ammonia and methanol before separation of alcohol and ammonia, thereby saving condensation equipment and cooling water, reducing production costs, and facilitating industrial production.

The invention provides a preparation method of a copper-silicon catalyst for catalyzing hydrogenation of dimethyl oxalate to prepare ethylene glycol. The method comprises the following steps: carrying out drying pretreatment on a carrier; the preparation method comprises the following steps: dissolving soluble copper salt and soluble metal salt used as an auxiliary agent in deionized water to obtain a precursor solution; and mixing the carrier with the precursor solution, adding an ammonia water solution, continuously stirring for a period of time, carrying out ion exchange, and carrying out ammonia distillation, washing, filtering, drying and roasting to obtain the copper-silicon catalyst. Through pretreatment of the carrier, the metal-carrier interaction on the surface of the carrier is changed, so that the copper-silicon catalyst obtains more high-activity Cu < + > in the hydrogen reduction process, and the hydrogenolysis capability and catalytic performance of the catalyst are improved; the copper-silicon catalyst prepared by the preparation method is used for catalyzing the reaction of preparing ethylene glycol by hydrogenation of dimethyl oxalate under the conditions of low temperature, low pressure and low hydrogen ester, and shows excellent catalytic performance and stability.

The utility model relates to the technical field of tail gas purification and recovery, and discloses a coal dimethyl oxalate tail gas purification and recovery device which comprises a bottom plate, one end of the top of the bottom plate is fixedly connected with a pressure pump, and the output end of one side of the pressure pump is fixedly connected with a buffer tank. According to the coal-to-dimethyl oxalate tail gas purification and recovery device, through mutual cooperation of the structures, coal-to-dimethyl oxalate tail gas can be efficiently purified and recovered, the resource utilization efficiency is remarkably improved, and the coal-to-dimethyl oxalate tail gas purification and recovery device is more convenient to produce and use in batches and is more practical.

The invention provides a silver-cobalt-silicon catalyst for synthesizing ethanol and ethylene glycol through catalytic hydrogenation of dimethyl oxalate and a preparation method of the silver-cobalt-silicon catalyst. The preparation method comprises the following steps: firstly, taking alkaline silica sol as a silicon source, taking soluble cobalt salt as a cobalt source, synthesizing a precursor of cobaltous silicate through an ammonia distillation method, then taking soluble silver salt as a silver source, and introducing a silver element into a cobaltous silicate layer through an impregnation method or the ammonia distillation method to prepare the silver-cobalt-silicon sphere catalyst through a synthesis method. The catalyst has high activity and high stability at a low reaction temperature. According to the novel silver-cobalt-silicon catalyst, the conversion rate of dimethyl oxalate can reach 99.9% in a wide temperature range, ethanol and ethylene glycol products with different proportions can be obtained at different temperatures, the total selectivity of ethanol and ethylene glycol reaches or exceeds 90%, and the novel silver-cobalt-silicon catalyst is suitable for producing ethanol and ethylene glycol products with different proportions according to different requirements.

The invention discloses a system and method for directly preparing battery-grade ferrous oxalate based on dimethyl oxalate, and the system comprises a rectifying tower which is used for carrying out hydrolysis reaction on dimethyl oxalate and discharging a hydrolysis solution through a liquid phase outlet; the decolorizing kettle is used for decolorizing the hydrolysis solution; the precipitation reaction kettle is used for carrying out mixed reaction and aging on the hydrolysis solution and ferric salt; the product recovery unit is connected with the precipitation reaction kettle and is used for separating and recovering reaction products to obtain battery-grade ferrous oxalate. According to the method, the hydrolysis solution of the dimethyl oxalate and the iron salt are directly mixed for precipitation reaction to prepare the battery-grade ferrous oxalate, high-energy-consumption steps such as crystallization and drying in the oxalic acid solid production process are reduced, meanwhile, the step of dissolving the solid oxalic acid is not needed, the heating energy consumption needed in the dissolving process is reduced, and the production efficiency is improved. The production energy consumption is greatly reduced, the production equipment and process are reduced, the cost is reduced, and the product yield is favorably improved.

The utility model belongs to the technical field of oxalate storage, and particularly relates to a harmless discharging device for volatile organic gas in a dimethyl oxalate storage tank, which comprises a storage tank and a liquid seal tank, the top end of the storage tank is connected with a discharging pipe, and a pressure transmitter for detecting air pressure in the tank is fixedly mounted on the storage tank. A regulating valve I in signal connection with the pressure transmitter is mounted on the discharge pipe, one end, far away from the storage tank, of the discharge pipe extends into the liquid seal tank and is positioned below the liquid level in the liquid seal tank, methanol is contained in the liquid seal tank, and the top end of the liquid seal tank is connected with a tail gas pipe. According to the utility model, organic matter gas in the storage tank is discharged into the liquid seal tank and is washed and dissolved by methanol, so that organic matters are prevented from being discharged into the atmosphere, zero emission of harmful substances is realized, and the device is environment-friendly.

The present invention discloses a method for removing coking substances from a hydrogenation catalyst for dimethyl oxalate. The steps are as follows: First, a mixed reagent composed of 70% - 90% tetrahydrofuran, 5% - 20% ethylene glycol monomethyl ether, and 5% - 20% methanol is used as a solvent to dissolve and elute the coking substances aggregated on the hydrogenation catalyst; then, an inert atmosphere containing tetrahydrofuran, methanol, and water is used for purging to remove the high-boiling esters and organic acids adsorbed on the catalyst, and then an inert atmosphere containing tetrahydrofuran and methanol is used for purging to remove the high-boiling alcohols adsorbed on the catalyst, so as to achieve the removal of the coking substances. This method can remove the coking substances on the hydrogenation catalyst for dimethyl oxalate, restore the activity lost due to the catalyst being covered by the coking substances, thereby greatly extending the service life of the catalyst; the method is simple, the cost is low, and the effect is good.

The application discloses a catalyst for preparing methyl acetate or ethanol by hydrogenation of dimethyl oxalate and a preparation method thereof. The catalyst comprises an active component, an auxiliary component and a carrier. The active component is a single substance or an oxide of Cu, the auxiliary component is a single substance or an oxide of W, the high active site is a Cu-W alloy interface and single Cu and W metals, and the carrier is one or more than two of silicon dioxide, aluminum oxide, zirconium oxide, zinc oxide, magnesium oxide and cerium oxide. The copper-tungsten alloy catalyst provided by the application has the advantages of structural stability, high mechanical strength, good heat conduction performance, high substrate conversion rate and high product selectivity. The preparation method is simple in steps, easy in raw material acquisition, low in cost, green in pollution, good in preparation repeatability and easy in scale production. The catalyst has extremely high stability and catalytic activity in the reaction of preparing methyl acetate or ethanol by hydrogenation of dimethyl oxalate, high ethanol or methyl acetate yield and high active component utilization rate.

The application discloses a triazine ring synthesis method, and belongs to the technical field of medical intermediate synthesis. The method is characterized in that 2-methylaminothiourea and dimethyl oxalate are used as raw materials, a nanometer catalyst of scandium triflate (Sc(OTf)3) or ytterbium triflate (Yb(OTf)3) is loaded on magnetic Fe3O4@SiO2, a cyclization reaction is carried out in an organic solvent, the catalyst is separated and recovered through an external magnetic field after the reaction is completed, and high-purity triazine rings are obtained through acidification, crystallization and drying of the reaction liquid. The catalyst has the advantages of high specific surface area, high catalytic activity, easy magnetic separation and recovery, and can be reused more than 6 times. The product yield can reach 93% to 96%, and the purity is greater than or equal to 99.6%. The method realizes green, efficient and low-cost synthesis of triazine rings.

The invention belongs to the technical field of coal ethylene glycol, and particularly relates to a process and a device for finely removing impurities from carbon monoxide after cryogenic separation of synthesis gas, the device comprises an impurity removal device, the impurity removal device comprises a desulfurization tank, a dechlorination tank and a decarbonylation tank which are sequentially connected in series, or an adsorption tower which is sequentially filled with desulfurization, dechlorination and decarbonylation adsorbents; the impurity removal device is arranged to remove trace hydrogen sulfide, hydrogen chloride, carbonyl iron and carbonyl nickel in CO after cryogenic separation, so that ppb-level removal of impurities in CO is realized, poisoning of a downstream dimethyl oxalate (DMO) synthesis catalyst is avoided, the service life of the catalyst is prolonged, the production cost of an enterprise is reduced, and the operation stability of the device is improved.

The application discloses a kind of molecular sieve supported silver monatomic catalyst and its preparation method and application.The catalyst is with molecular sieve as carrier, by silver precursor salt aqueous solution is impregnated to molecular sieve, after drying and with carbon powder mixing, again be placed in joule heat in-situ heating device, at 600 DEG C~1200 DEG C high temperature pyrolysis 5~8 seconds preparation;Wherein silver element mass content is 0.2 wt%~3 wt%.The catalyst prepared by the application realizes that silver monatomic atom is highly dispersed on molecular sieve, and metal utilization rate reaches 100%.The catalyst is applied to oxalic acid dimethyl ester electrocatalytic reduction coupling preparation tartaric acid dimethyl ester reaction, and excellent catalytic performance is shown: at optimum potential, target product tartaric acid dimethyl ester selectivity is as high as 95.3%, faraday efficiency reaches 82.9%, conversion frequency reaches 1880 h ‑1 , and has excellent long-term electrochemical stability.

The invention discloses a copper-based catalyst which comprises a carrier and an active component, and the carrier is silicon nitride; the active component is Cu monatomic, and the Cu monatomic is anchored on the surface of the silicon nitride through a Cu-N bond. The invention also discloses a preparation method of the copper-based catalyst and application of the copper-based catalyst in catalyzing selective hydrogenation of dimethyl oxalate to prepare methyl glycolate.

The invention provides a method and system for preparing dimethyl carbonate through dimethyl oxalate decarbonylation, and the method comprises the following steps: dimethyl oxalate is subjected to decarbonylation reaction in a reactor, and a gas phase product and a first liquid phase product are respectively obtained from the decarbonylation reactor: the first liquid phase product enters a dimethyl carbonate product tower; cooling the gas-phase product, carrying out gas-liquid separation to obtain a gas-phase material and a second liquid-phase product, and feeding the gas-phase material and the second liquid-phase product into the carbonate product tower; absorbing by-products containing carbon dioxide and dimethyl ether by the gas-phase material through dimethyl carbonate, and desorbing and removing by-products containing carbon dioxide and dimethyl ether by the discharged liquid-phase absorption material in a desorption tower. According to the method, a separate discharging mode is adopted, condensate of a liquid-phase product and condensate of a gas-phase product are treated at the same time through the dimethyl carbonate product tower, the process is simple, and energy consumption is low; dimethyl carbonate is adopted as an absorbent, carbon dioxide and dimethyl ether in carbon monoxide product gas can be effectively separated, the process is simple, and energy consumption is low.

The invention relates to a method for generating dimethyl carbonate by decarbonylation of dimethyl oxalate, which comprises the following steps: dissolving dimethyl oxalate in a solvent to prepare a solution, adding a catalyst, and carrying out decarbonylation reaction to obtain dimethyl carbonate, the catalyst comprises a main catalyst and a cocatalyst, the main catalyst is alkoxide of alkali metal, and the cocatalyst is one or more of pyridine, acetone or triethylamine. According to the method, an alkoxide decarbonylation catalyst system of a single alkali metal is changed into a multi-element catalyst system by adding the auxiliary agent, so that the liquid-phase decarbonylation reaction can be carried out at low temperature and low pressure, the reaction condition is milder, the equipment cost and energy consumption of the reaction are reduced, and the catalyst can be recycled for multiple times and has good economic benefits.

The invention provides preparation and application of a dimethyl oxalate high-selectivity hydrogenation catalyst. Black phosphorus is synchronously introduced in the ammonia distillation process of the catalyst, after hydrothermal aging, the black phosphorus and the catalyst are roasted and molded together, and finally the dimethyl oxalate high-selectivity hydrogenation catalyst is prepared. The prepared catalyst is used for a dimethyl oxalate hydrogenation reaction, black phosphorus is introduced in the process of forming a catalyst precursor by ammonia distillation, black phosphorus is promoted to be dispersed more uniformly in the catalyst and bonded with active metal more firmly, and black phosphorus lone pair electrons are utilized to regulate the electronic structure of the active metal to promote the hydrogenation activity and the selectivity of a target product to be improved; the reaction temperature and pressure are effectively reduced, the black phosphorus two-dimensional fold structure and the formed Si-O-P-M bond are utilized to promote dispersion of metal atoms, the interaction with the carrier is enhanced, the stability of the catalyst is further improved, and the service life of the catalyst is further prolonged. The adopted modification method is simple in process, convenient to operate and easy to industrialize, meanwhile, the service life of the catalyst can be effectively prolonged, and efficient utilization of the metal catalyst is promoted.

The invention discloses a system and method for recycling high-temperature condensate from ethylene glycol synthesis, comprising the following steps: S1, dividing the steam condensate generated by the ethylene glycol synthesis system into two parts, one part preheating the dimethyl oxalate from the dimethyl oxalate buffer tank to a first temperature, and the other part preheating the boiler feed water to a second temperature; S2, transporting the steam condensate after preheating the dimethyl oxalate and the boiler feed water to the condensate main pipe. In the present invention, the steam condensate generated by synthesizing ethylene glycol is used to preheat the dimethyl oxalate and the boiler feed water, which, on the one hand, reduces the use of high-grade steam when 3.5MpaG steam is used to preheat the dimethyl oxalate and the boiler feed water in the prior art, increases the amount of byproducts of 0.8MPa steam, and achieves the purpose of recovering high-grade latent heat from low-grade sensible heat; on the other hand, the heat of the steam condensate is recovered in the form of material heat exchange, and the temperature of the condensate can be finally reduced, and all the heat is recovered, which is superior to the market ORC and condensate refrigeration technology, and has low investment costs and high investment returns.

The invention discloses an ammonia-alcohol separation device which comprises a methanol absorption section, a methanol condensation extraction section, an ammonia absorption section and an ammonia absorption raw material preparation section which are sequentially arranged from top to bottom, the methanol absorption section absorbs methanol in gas through desalted water, and methanol extracted from the methanol condensation extraction section is sent to a dimethyl oxalate synthesis device; the ammonia absorption section is used for absorbing ammonia in the gas through a methanol solution of dimethyl oxalate. The device further comprises a dimethyl oxalate rectification device and an oxamide synthesis device. The chemical reaction in the oxamide production process is used for replacing rectification and washing procedures in the prior art, and complete conversion of ammonia, internal circulation of methyl alcohol in the dimethyl oxalate synthesis and oxamide co-production device and effective utilization of low-level heat energy of dimethyl oxalate are achieved. The invention also discloses a method for co-production of dimethyl oxalate and oxamide by using the ammonia-alcohol separation device.

The utility model relates to the field of a dimethyl oxalate synthesis process, in particular to a nitric acid feeding line and dimethyl oxalate production equipment, an original nitric acid liquid inlet subline is cancelled, and a nitric acid boundary valve is arranged at the output end of a nitric acid feeding system to control the flow of nitric acid entering a specific area or system, so that the nitric acid is ensured to flow in a specified range; it is ensured that nitric acid can stably and continuously enter the next link through a nitric acid feeding valve; through the arrangement of the nitric acid drainage regulating valve and the check valve behind the nitric acid feeding valve, after nitric acid supplementing is stopped, the nitric acid in the pipeline is released through the nitric acid drainage regulating valve, nitric acid accumulated liquid stored in the pipeline is avoided, and therefore the situation that the nitric acid flows backwards and reacts with liquid stored in the pipeline is doubly avoided; and the safety of the pipeline is further improved. The problem that the accident risk is high due to the fact that nitric acid feed of an existing nitric acid reduction tower accumulates in a pipeline and reacts with alcohol-containing liquid of a methyl nitrite regeneration tower reversely into the nitric acid pipeline is solved.

The invention belongs to the technical field of NO gas preparation in the production process of coal ethylene glycol devices, and discloses a start-up method of an NO gas production device in coal ethylene glycol, which comprises the following steps: step 1): preparing materials; according to the driving method disclosed by the invention, key process indexes such as nitric acid dropping speed, pressure, temperature and NO gas flow are strictly controlled in the whole driving process, so that severe reaction and overpressure safety accidents are prevented, and the gas quantity required by a downstream dimethyl oxalate synthesis unit is stably supplied.

The present application relates to a kind of preparation methods and systems of electronic grade dimethyl carbonate prepared from dimethyl oxalate, the method comprises the following steps: dimethyl oxalate is preheated and sent into decarboxylation reactor to carry out decarboxylation reaction, carbon monoxide, dimethyl carbonate and other light components are extracted from the top of decarboxylation reactor, and heavy components are extracted from the bottom of decarboxylation reactor;Carbon monoxide, dimethyl carbonate and other light components extracted are separated after gas-liquid, and liquid phase dimethyl carbonate is sent into rectifying column to carry out rectification purification;Electronic grade dimethyl carbonate product is obtained by crystallization purification in refrigeration crystallization device after rectification, and crystallization mother liquor returns rectifying column;Decarboxylation reactor is three-stage reaction tower, and rectifying section, reaction section, stripping section are sequentially from top to bottom.The present application is completely reacted by the design of three-stage decarboxylation reactor;Heavy components generated are extracted in real time, and catalyst stability is high;Electronic grade DMC is prepared by using rectifying column coupled with crystallization tower, and the yield of DMC is significantly improved.

The invention relates to a synthesis method of dimethyl oxalate, and mainly solves the technical problems of high reaction hot spot temperature, poor dimethyl oxalate selectivity and low space time yield in the prior art. According to the technical scheme, carbon monoxide, nitrogen and methyl nitrite (MN) are used as raw materials, and under the conditions that the inlet temperature is 70-100 DEG C, the volume space velocity is 1000-5000h <-1 >, the CO molar concentration is 10-40%, the CO / MN molar ratio is 1.0-3.0 and the reaction pressure is 0.05-2.0 Mpa, the raw materials pass through a Pd catalyst diluted by small balls with low specific surface area, large aperture and low acid content, the hot-spot temperature of a bed is lower than 125 DEG C, and the reaction is carried out for 1-2 hours, so that the methyl nitrite (MN) is obtained. According to the technical scheme, the problems are well solved, the selectivity of the dimethyl oxalate is larger than 98% in the long-time operation process, the space time yield of the dimethyl oxalate is larger than 750 g / (L.h), and the method can be used for industrial production of synthesizing the dimethyl oxalate through oxidative coupling of carbon monoxide.

The invention discloses a filling method for retarding coking of a hydrogenation catalyst and reducing basic pressure difference of a reactor, which comprises the following steps: an inert material is selected according to the size and bulk density of the hydrogenation catalyst, and the inert material comprises at least one of a Raschig ring, a Pall ring and an inert ceramic ball; calculating the ratio of the inert material to the hydrogenation catalyst, and mixing the inert material with the hydrogenation catalyst according to the ratio; and filling the mixed catalyst mixture into a tube nest. The inert material is used for diluting the active center of the catalyst, dispersing reaction heat and reducing the accumulation of heat at the upper part of the tube nest, so that the reaction intensity is actively reduced, the coking speed is directly slowed down, the basic pressure difference of the reactor is reduced, and the problems that the catalyst is easy to coke and the bed resistance is increased in the process of preparing ethylene glycol by hydrogenation of dimethyl oxalate are effectively solved; reaction conditions are optimized from a filling source, and the service life of the catalyst is prolonged.

The invention discloses a synthetic method of 1, 2, 4-triazole-3-carboxylic acid methyl ester, and belongs to the field of organic synthesis. The preparation method comprises the following steps: by taking formamidine acetate, hydrazine hydrate and dimethyl oxalate as raw materials, carrying out one-pot reaction to obtain the 1, 2, 4-triazole-3-carboxylic acid methyl ester. Compared with the prior art, the method has the advantages of short synthesis process route, short reaction time and simplicity in operation; and the synthesis process is few in three wastes, environment-friendly and green. Meanwhile, the synthesis process is safe and reliable, reaction conditions are mild, and dangerous processes such as diazotization and desulfurization are not involved.

The utility model discloses a solid catalyst reactive distillation device for producing ethyl methyl oxalate and diethyl oxalate, which comprises a dimethyl oxalate storage tank and an ethanol storage tank, the dimethyl oxalate storage tank and the ethanol storage tank are respectively connected with a raw material preheater, the raw material preheater is connected with a pre-reactor, and the pre-reactor is connected with a reaction kettle. The pre-reactor is connected with the reactive distillation tower through a pipeline, the top of the reactive distillation tower is connected with the first water-cooling heat exchanger, a tower kettle is connected with the reboiler and the methyl ethyl oxalate conversion reactor, and the methyl ethyl oxalate conversion reactor is connected with the second water-cooling heat exchanger. The device is provided with a catalytic rectifying section with a solid catalyst and a methyl ethyl oxalate conversion reactor. According to the device, dimethyl oxalate can be completely converted, the proportion of ethyl methyl oxalate to diethyl oxalate can be adjusted at will, the reaction product methanol can be separated and removed in time during reaction, the reaction conversion rate can be increased, reaction heat can be efficiently utilized, and continuous and energy-saving production is achieved.

The invention relates to preparation and application of a catalyst, in particular to a preparation method of a silver-based porous boron nitride catalyst, and the catalyst prepared by the method is applied to the field of dimethyl oxalate hydrogenation and is used for preparing methyl glycolate. The preparation method comprises the following steps: carrying out ultrasonic treatment on porous boron nitride in water to form a boron nitride suspension, dissolving various metal salt precursors required for preparing the catalyst, adding a proper amount of ammonia water to form a complex after the metal salt precursors are completely dissolved in water, dropwise adding the obtained complex into the boron nitride suspension, heating in a water bath, and carrying out vacuum drying to obtain the boron nitride catalyst. The method is simple in preparation and good in process repeatability, metal silver is highly dispersed in porous boron nitride through an ammonia distillation method, and under the reaction conditions that the temperature is 200 DEG C, the pressure is 2.5 Mpa, H2 / DMO is 80 and WHSV is 0.625 h <-1 >, the dimethyl oxalate conversion rate reaches 99%, and the methyl glycolate selectivity can reach 95%.

The invention relates to the technical field of organic chemical synthesis, in particular to a catalyst and a process for preparing methyl glycolate and co-producing methyl formate through methanol dehydrogenation coupling oxalate hydrogenation, which comprises the following steps: S1) providing a coal-to-ethylene glycol device which comprises a methanol rectifying tower, a DMO synthesis system, a DMO refining system, a DMO hydrogenation reactor and a condensing system; s2) taking methanol extracted from a methanol rectifying tower as a raw material, and carrying out anaerobic dehydrogenation reaction under the action of the catalyst in any one of claims 1-2 or the catalyst prepared by the preparation method in claim 3 to obtain methyl formate, H2 and CO; and S3) by taking dimethyl oxalate extracted from a DMO refining system as a raw material, carrying out hydrogenation reaction under the action of the catalyst in any one of claims 4-5 or the catalyst prepared by the preparation method in claim 6 to obtain methyl glycolate and methanol.