87 results about "Dimethyl oxalate" patented technology

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 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 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 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 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.

The invention discloses a method for increasing the load of a dimethyl oxalate synthesis system and reducing the content of methyl nitrite in the system, and the method comprises the step of arranging a tubular reactor connected with a reactor A / B in parallel on a pipeline between a preheater and a gas removal tower. After the rotating speed of a compressor is adjusted, the circulating flow of outlet gas is controlled to be 420000-440000 Nm < 3 > / h, and meanwhile effective gas components entering the tubular reactor and the reactor A / B in the system are controlled to comprise 16%-22% of CO, 3%-6% of NO and 12%-14% of MN; s2, after feeding of the reactor A / B and the tubular reactor is completed, a flow adjusting valve at an inlet of the tubular reactor is immediately adjusted, the ratio of the flow of the inlet of the reactor A / B to the flow of the inlet of the tubular reactor is controlled to be 4.5-5.5: 1, and meanwhile the content of methyl nitrite in the system is controlled to be 14.5%-15.8%. The bottleneck problem of high safety production risk caused by low dimethyl oxalate synthesis yield and high methyl nitrite content in the original system is solved.

The invention discloses a copper-silicon catalyst for plasma treatment as well as a preparation method and application of the copper-silicon catalyst. According to the method, a copper-silicon catalyst precursor prepared by a traditional ammonia distillation method is subjected to dielectric barrier discharge plasma treatment in the atmosphere of H2 / Ar and the like, and traditional high-temperature roasting and reduction processes are replaced. According to the method, efficient reduction and high dispersion of copper can be achieved at the room temperature, the Cu < + > / Cu0 proportion is regulated and controlled, and the strong interaction between metal and a carrier is enhanced. The catalyst is used in a reaction for preparing ethylene glycol through hydrogenation of dimethyl oxalate, the activity, selectivity and stability of the catalyst are higher than those of a traditional heat treatment catalyst, the dimethyl oxalate conversion rate reaches up to 100%, the ethylene glycol selectivity is larger than 97%, and the stability reaches 1000 h or above. The method is simple in process, low in energy consumption and environment-friendly, and has a wide industrial application prospect.

The invention discloses a preparation method of lithium difluoro (oxalato) borate. Lithium hydroxide, trimethyl borate, dimethyl oxalate and anhydrous ammonium bifluoride steam are used as raw materials to react in an ionic liquid medium. The method adopts a plasma activation technology, can be efficiently carried out in a low-temperature environment without traditional heating, not only shortens the reaction period, but also can inhibit fluorine source decomposition, oxalate hydrolysis and other side reactions, improves the selectivity of a target product, and uses the ionic liquid as a reaction medium, and the high polarity and low volatility of the ionic liquid can ensure the uniform dispersion of raw materials. Meanwhile, supercritical carbon dioxide extraction replaces traditional recrystallization, one-step purification is achieved by means of the selective dissolution characteristic of supercritical carbon dioxide extraction, the process steps are simplified, and solvent residues are reduced.

The invention discloses a preparation method and application of a nitrogen-anchored alkali metal monatomic supported catalyst. The catalyst is composed of an active component, a metal oxide auxiliary agent and a nitrogen modified carrier, and according to the preparation method, metal single atoms are anchored through the nitrogen modified carrier, and stable loading of high-dispersity active sites is achieved in combination with optimized roasting conditions (400-900 DEG C). The catalyst has excellent performance in synthesis of dimethyl carbonate (DMC) by decarbonylation of dimethyl oxalate: taking Cs (3%)-Ce (2%) / activated carbon as an example, the conversion rate of dimethyl oxalate reaches 82.05% and the selectivity of DMC reaches 86.91% under the conditions that the temperature is 220 DEG C, the dosage of the catalyst is 0.5 g and the reaction is performed for 2 h. A nitrogen anchoring strategy effectively inhibits metal agglomeration, a carrier microporous structure promotes mass transfer, and the specific surface area (704.38 m / g) and catalytic performance are kept stable after recovery. The catalyst has the advantages of high activity, high selectivity, low cost and easiness in industrialization, and an efficient catalyst solution is provided for synthesizing dimethyl carbonate by decarbonylation of dimethyl oxalate.

This invention proposes a heterogeneous catalyst and its application in the decarbonylation of alkyl oxalate to alkyl carbonate. The heterogeneous catalyst is a transition metal-modified organic amine-grafted polystyrene resin obtained by grafting chloromethylated polystyrene resin with an organic tertiary amine, followed by modification with a transition metal anion complex. This invention utilizes the heterogeneous catalyst to fully utilize dimethyl oxalate, an important intermediate in the coal-to-ethylene glycol process. By decarbonylating dimethyl oxalate, it can be efficiently converted to dimethyl carbonate and its derived alkyl esters under mild conditions.

This invention relates to the field of catalyst preparation technology, specifically to a copper-based catalyst for the hydrogenation of dimethyl oxalate and its preparation method. The catalyst is a Cu / SiO2 catalyst with a copper content of 5-25 wt% as the active component. It is prepared from raw materials such as a silicon source, a copper source, a hydroxyl protectant, and a hydrothermal promoter via a low-pressure ammonia stripping method. During the preparation process, by protecting the silanol hydroxyl groups and optimizing the ammonia stripping and complexation conditions, copper is highly dispersed and stable on the silicon support surface, effectively avoiding copper particle sintering and desilication problems. This catalyst exhibits excellent performance in the hydrogenation of dimethyl oxalate to ethylene glycol. Under reaction conditions of 170℃ and 2.8 MPa, the dimethyl oxalate conversion rate is ≥99%, the ethylene glycol selectivity is ≥97%, and the continuous operating time is ≥3000 h. It can significantly inhibit the formation of byproducts and carbon deposition, extend service life, and simultaneously reduce separation and purification energy consumption and catalyst replacement frequency. The raw materials used are conventional and controllable, and the preparation process is suitable for industrial production, showing broad application prospects.

The invention belongs to the field of catalysts, and particularly relates to a catalyst which comprises a carrier, an active component and an auxiliary agent, the active component and the auxiliary agent are loaded on the carrier, the active component is selected from one or more of copper, copper oxide and copper salt, and the auxiliary agent is fullerene. The carrier is selected from one or more of oxides of magnesium, boron, silicon, scandium, gallium, yttrium, zirconium, zinc, indium, lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, terbium and ytterbium elements; the dispersity of the active component in the catalyst is 20%-100%. The invention also relates to a method for preparing the catalyst and a method for preparing methyl glycolate. The catalyst disclosed by the invention is high in active component dispersity, large in BET specific surface area, large in average pore size, high in mechanical strength, good in stability and long in service life; the catalyst can catalyze the hydrogenation reaction of dimethyl oxalate under low pressure, the raw material conversion rate is high, and the selectivity of methyl glycolate is high.

The invention provides a system and a method for preparing oxalic acid by hydrolyzing dimethyl oxalate. The system comprises a pre-reaction kettle, a methanol tower, a hydrolysis tower, a methanol tower condenser, a mother liquor heat exchanger and a crystallization unit which are connected with one another through pipelines. The method comprises the following steps: feeding a mixed solution of fresh dimethyl oxalate and desalted water and a thermally coupled circulating mother solution into a pre-reaction kettle for primary hydrolysis reaction, then feeding into a methanol tower for reactive distillation, returning a tower bottom solution to a hydrolysis tower material for reactive distillation, and returning a gas phase at the top of the hydrolysis tower to the bottom of the methanol tower material for feeding, refined methanol is extracted from the top of the methanol tower, one stream of oxalic acid hydrolysate in the kettle of the hydrolysis tower is mixed with the mother liquor and enters the pre-reaction kettle, and the other stream of oxalic acid hydrolysate is thermally coupled with the mother liquor and then enters the crystallization unit to obtain refined oxalic acid. The dimethyl oxalate conversion rate is high, the methanol purity is high, the monomethyl oxalate content in the oxalic acid hydrolysate is low, oxalic acid crystallization and thermal coupling of the mother liquor and the hydrolysate are facilitated, and the overall energy consumption is reduced.

The application discloses a method for preparing glycol and / or methyl glycolate by dimethyl oxalate hydrogenation, which comprises the following steps: (1) mixing methanol with hydrogen and then feeding into a heat exchanger for preheating to obtain a mixed material; (2) mixing the mixed material obtained in step (1) with dimethyl oxalate, heating through a feeding heater and then performing hydrogenation reaction to generate a reaction product comprising methyl glycolate and / or glycol. The method can greatly improve the heat exchange efficiency of the heat exchanger, reduce the heat load of the subsequent feeding heater, reduce steam consumption, thereby saving energy consumption, and avoiding the crystallization problem of dimethyl oxalate after being mixed with low-temperature hydrogen.

The invention relates to an oxalate hydrogenation catalyst carrier, a catalyst and a preparation method, and the method comprises the following steps: enabling gasified fly ash to electrostatically adsorb a cationic surfactant type pore-foaming agent, hydrolyzing tetraethyl orthosilicate under the action of the cationic surfactant and ammonia water, and forming a silicon dioxide shell layer on the surface of the gasified fly ash, after the cationic surface active agent is completely decomposed through calcination, a porous structure is formed on a silicon dioxide shell layer of the gasified fly ash to serve as an active center load; according to the method, the defect that strong acid / strong base is adopted in the traditional technology can be effectively avoided, meanwhile, compared with KCC-1, MCM-41, SBA-15 and other silicon dioxide carriers, the purpose of greatly reducing the carrier cost can be achieved on the premise that the conversion rate of dimethyl oxalate is as high as 98.61% through a catalyst prepared based on the carrier dipping active metal, and in addition, the method has the advantages that the cost of the carrier is greatly reduced. The gasified fly ash which is used as solid waste is also developed with high value.

The invention provides a preparation method for coproduction of hydroxyethyl piperazine and triethylene diamine, which comprises the following steps: by taking dimethyl oxalate directly prepared from coal as a key raw material, carrying out catalytic hydrogenation reduction reaction on the dimethyl oxalate to obtain alpha-methyl glycolate; then the alpha-methyl glycolate and piperazine are subjected to a nucleophilic acyl substitution reaction, and an intermediate product 2-hydroxy-1-(piperazine-1-yl) ethanone is generated; and finally, carrying out hydrogenation reduction on the intermediate product under the action of a catalyst to synchronously obtain target products, namely hydroxyethyl piperazine and triethylene diamine. According to the method, double products of hydroxyethyl piperazine (medicine and dye intermediates) and triethylene diamine (a polyurethane catalyst and a rubber accelerator) are synchronously generated, the total yield of hydroxyethyl piperazine reaches 72% or above, the yield of triethylene diamine reaches 70% or above, the two products are high-added-value fine chemical products, and compared with a single product route, the method has the advantages that the yield is high, and the cost is low. The economic benefit of unit raw materials can be greatly improved, and the resource utilization rate is maximized. The invention belongs to the technical field of organic synthesis.

The application provides a method for preparing dimethyl carbonate by decarboxylation of dimethyl oxalate, and relates to the technical field of dimethyl carbonate preparation, and specifically comprises the following steps: adding dimethyl oxalate into a reactor, heating to melt the dimethyl oxalate, adding a catalyst into the system, and obtaining dimethyl carbonate by catalytic decarboxylation; the catalyst is an alkali metal alcoholate. The catalyst selected by the preparation method is low in price and easy to prepare; under the catalytic condition of the catalyst, the conversion rate of raw materials is high, the selectivity of the product, i.e. dimethyl carbonate, is high, and the by-products are few. The preparation method is simple in process flow and mild in process condition, can reduce industrial cost and improve industrial production efficiency in many aspects, and is suitable for industrial production.

The invention discloses a synthesis method and a synthesis system of erythritol. The synthesis method of the erythritol comprises the following steps: contacting dimethyl oxalate and methyl glycolate with a condensation catalyst to carry out condensation reaction, and carrying out hydrogenation reaction on the obtained condensation intermediate and hydrogen under the action of a hydrogenation catalyst to obtain the erythritol. According to the method disclosed by the invention, the erythritol with high additional value can be prepared through two steps of condensation and hydrogenation, and the yield of the erythritol can be obviously improved.

The invention relates to a novel method for preparing methyl glycolate (MG) by efficiently catalyzing hydrogenation of dimethyl oxalate (DMO). According to the method, a CuO-NiO composite metal oxide is used as a catalyst, and the process of preparing MG from DMO can be efficiently realized in a tank reactor and a fixed bed reactor. Compared with the prior art, the method has the advantages that the catalyst preparation process is simple, the cost is low, the target product selectivity is relatively high, the reaction conditions are relatively mild, and a novel method for efficiently and economically preparing MG is provided.

The invention discloses a method for purifying dimethyl oxalate, which comprises the following steps: 1) introducing crude dimethyl oxalate into a pre-separation tower to remove light components in the crude dimethyl oxalate; 2) introducing the tower kettle material obtained in the step 1) into a purification-vaporization tower at a temperature close to a bubble point; the purification-vaporization tower comprises a tower body, the tower body is filled with a tower plate or filler, a tower kettle of the tower body is provided with a reboiler (2), and a feeding end of the purification-vaporization tower is positioned in the middle of the tower body; 3) adjusting the vaporization rate of the material in the tower to 90-98%, and obtaining a high-purity gas-phase DMO product from the tower top of the purification-vaporization tower; and discharging the kettle liquid rich in heavy components from the bottom of the tower. According to the invention, purification and vaporization functions are integrated in the purification-vaporization tower, the system is simple, control variables are few, long-period stable operation is easy to realize, and the instability of operation of a traditional rectification tower under an extremely small reflux ratio is avoided.

The invention relates to poly (ethylene glycol terephthalate-co-isosorbide oxalate) and a polymerization method thereof, and belongs to the technical field of high polymer materials. The preparation method of the copolyester comprises the following steps: directly esterifying terephthalic acid and ethylene glycol to synthesize bis (2-hydroxyethyl) terephthalate; carrying out ester exchange on the dimethyl oxalate and isosorbide to synthesize isosorbide oxalate; and carrying out polycondensation to prepare the copolyester high polymer material. The material disclosed by the invention is a repetitive unit consisting of bis (2-hydroxyethyl) terephthalate and isosorbide oxalate, and has the glass transition temperature of higher than 90 DEG C, the intrinsic viscosity of higher than 0.50 dl / g and the impact strength of higher than 4.2 kJ / m < 2 >.

The invention belongs to the technical field of ethylene glycol synthesis, and particularly relates to a gas phase circulation component self-control method for a dimethyl oxalate hydrogenation ethylene glycol preparation device. Comprising the steps that (1) the fresh hydrogen supplementing amount FIC001 is controlled through the circulating hydrogen compressor outlet pressure PIC001 and the theoretical hydrogen demand amount FIC006, the circulating hydrogen compressor outlet pressure PIC001 is kept within a set range with the PIC001 as a main variable, the FIC001 as an auxiliary variable and the FIC006 as a feedforward signal, and FIC006 = FT004 * 871.05; (2) under the condition that the hydrogen-ester ratio AIC004 is given, the system purge flow FT002 is adjusted through a formula, so that the reaction molar ratio of hydrogen to dimethyl oxalate is accurately controlled.

The application discloses application of a Mo / SiO2-Cu / ZnO / Al2O3 catalyst in preparation of ethanol through DMO hydrogenation catalysis, and Mo / SiO2 in the Mo / SiO2-Cu / ZnO / Al2O3 catalyst first catalyzes hydrogenation conversion of dimethyl oxalate into methyl acetate, and then Cu / ZnO / Al2O3 catalyzes hydrogenation conversion of the methyl acetate into ethanol. The Mo / SiO2-Cu / ZnO / Al2O3 catalyst is a two-stage filling catalytic system, and the filling modes include Mo-CuZnAl two-stage filling, Mo-mix-CuZnAl physical mixing filling and CuZnAl-Mo two-stage filling. The Mo / SiO2 catalyst and the Cu / ZnO / Al2O3 catalyst are simultaneously applied in preparation of ethanol through dimethyl oxalate hydrogenation synergistic catalysis, and the Mo / SiO2 catalyst and the Cu / ZnO / Al2O3 catalyst can exhibit stronger hydrogenation activity, excellent catalytic activity and higher ethanol selectivity.

The invention belongs to the fields of coal chemical industry, natural gas chemical industry, calcium carbide chemical industry, coking and the like, and discloses an efficient and energy-saving refining process method and device for preparing high-quality ethylene glycol from synthesis gas. According to the process, by-product low-pressure steam of a dimethyl oxalate carbonylation reaction and a hydrogenation reaction is compressed and then is used for supplying heat to a reboiler of an ethylene glycol rectification device; meanwhile, condensation heat of gas phases at the tops of the dihydric alcohol removal tower and the EG product refining tower is creatively utilized to respectively produce different grades of steam, one stream is directly used for a reboiler at the middle lower part of the monohydric alcohol recovery tower, and the other stream of low-grade steam is returned to a compressor to be recycled by a system. According to the invention, cascade and cyclic utilization of waste heat in the reaction and rectification process is realized, consumption of externally supplied steam and circulating water is remarkably reduced, the high-efficiency heat exchanger is adopted, the temperature of the cold side and the hot side of the reboiler is reduced, impurities caused by high temperature are reduced, and the ultraviolet light transmittance and the yield of polyester-grade ethylene glycol are effectively improved.

The invention discloses preparation of a gold-based catalyst growing on a carbon coating gas diffusion electrode in situ and application of the gold-based catalyst to synthesis of oxalate through electric carbonylation, and the method comprises the following steps: dissolving gold precursor salt and copper precursor salt in a water-ethanol mixed solution, and ultrasonically mixing uniformly at room temperature to obtain a yellow / yellow green solution; and uniformly coating the yellow / yellow green solution on the surface of GDS, drying, reducing in a beaker by using a sodium borohydride aqueous solution, and repeatedly washing with water and ethanol to obtain the electrode catalyst growing on the GDS in situ. The gold and gold-copper alloy electrocatalyst prepared by the method solves the problems of carbon monoxide gas diffusion and catalyst stability in the process of preparing dimethyl oxalate (DMO) through electrocatalytic oxidation carbonylation, and achieves the purposes of Faraday efficiency (FE%) and yield increase in the process of preparing DMO through electrocatalytic oxidation carbonylation. An electro-catalytic performance test shows that the performance of the gold and gold-copper alloy electro-catalyst is superior to that of other metal-loaded catalysts in a reaction for preparing dimethyl oxalate through electro-catalysis of methanol coupling CO.