112 results about "Acetylene hydrogenation" patented technology

A process for the selective hydrogenation of dienes and acetylenes in a mixed hydrocarbon stream from a pyrolysis steam cracker in which a front end a one step acetylene hydrogenation is carried out using catalyst comprising (A) 1 to 30 wt. % based on the total weight of the catalyst of a catalytic component of nickel only or nickel and one or more elements selected from the group consisting of copper, rhenium, palladium, zinc, gold, silver, magnesium, molybdenum, calcium and bismuth deposited on (B) a support having the a BET surface area of from 1 to about 100 m²/gram, total nitrogen pore volume of from 0.2 to about 0.9 cc/gram and an average pore diameter of from about 110 to 450 Å under conditions of temperature and pressure to selectively hydrogenate acetylenes and dienes. The process hydrogenates the dienes and acetylenes to olefins without loss of ethylene and propylene in the light and heavy products which eliminates the need for further processing of the heavier stream. In addition the amount of polymerization in the lower part of the distillation column reactor is reduced.

The invention discloses a palladium monatomic catalyst, preparation of the palladium monatomic catalyst and application of the palladium monatomic catalyst in acetylene hydrogenation reaction. The palladium monatomic catalyst is prepared by the following steps: with Pd as the active component and ZnO as a carrier, dipping, and carrying out high-temperature reduction to form an alloyed monatomic catalyst. Under the conditions of low temperature, wide temperature range (60-300 DEG C) and high space velocity (such as 180000mL/g.h) and in pure acetylene atmosphere and acetylene atmosphere with a great amount of acetylene, a small amount of the catalyst (such as 10mg) has excellent activity, selectivity and stability. The invention provides a preparation method of the palladium monatomic catalyst. The preparation method is simple and feasible, very good catalytic performance is shown in preparation of acetylene by selectively hydrogenating in the acetylene and the industrial application prospect is good.

The invention provides a vinyl acetylene hydrogenation catalyst and a preparation method and applications thereof, wherein the vinyl acetylene hydrogenation catalyst comprises the following compositions in parts by weight: 0.01-30 parts of active component, 40-99.989 parts of carriers and catalyst promoter, wherein the mole ratio of the catalyst promoter to the active component is (0.1-10):1. According to the vinyl acetylene hydrogenation catalyst, the acetylene hydrogenation activity and butadiene selectivity are high, the vinyl acetylene hydrogenation catalyst can be effectively used in vinyl acetylene hydrogenation reaction so as to further efficiently prepare butadiene.

The present invention provides a method and reactor system for hydrogenating acetylenes present in the olefin stream derived from the following streams, alone or in combination: petroleum catalytic cracking process and/or oxygenate-to-olefin reactor, such as methanol-to-olefin (MTO) reactor, in an olefin production plant before the distillation steps, wherein the acetylene hydrogenation occurs before or just after the acid gas removal step.

The invention discloses an atomic-scale dispersed palladium-based nanometer diamond/graphene composite material catalyst, a preparation method and applications thereof, and belongs to the technical field of catalysts for selective hydrogenation reactions of acetylene, wherein nanometer diamond is subjected to high temperature calcination treatment in an inert atmosphere to obtain a nanometer diamond/graphene structure carbon material, and palladium is dispersed and fixed in the graphene shell layer in an atomic form. According to the present invention, the catalyst hydrogenates acetylene to generate ethylene in a mixed raw material gas, wherein the use temperature of the catalyst is 80-200 DEG C; by dispersing palladium on the nanometer diamond/graphene material in an atomic scale manner,the atomic-scale dispersed palladium-based nanometer diamond/graphene composite material catalyst can effectively catalyze the conversion of acetylene into ethylene and has significantly improved acetylene hydrogenation selectivity compared to the traditional palladium-based carbon materials and the commercial palladium catalysts, has good stability, and is not easily deactivated during the reaction.

Provided are slurry bubble column technology for preparing ethylene through acetylene hydrogenation and a device thereof. The slurry bubble column technology includes adding water and then catalyst into a reactor, filling inert gases for replacing, heating, leading gas mixture of acetylene and hydrogen to enter in the reactor for reacting from the bottom of the reactor through a gas distributor, finally exhausting reaction products and unreacted feed gases from the top of the reactor, and separating to obtain the ethylene. The unreacted feed gases and the feed gases are mixed and then enter the reactor again for reacting. The reactor comprises a reaction gas inlet at the bottom, the gas distributor and a material liquid exhaust port, a reactor barrel body is arranged on an expended section on the upper portion of a slurry bubble column reactor, and a catalyst feeding port and a gas outlet are arranged at the top of the reactor. The slurry bubble column for preparing the ethylene through the acetylene hydrogenation is simple in structure, overcomes the phenomenon of temperature runaway in a fixed bed reactor and improves the conversion rate and selectivity of the reaction, and the operation is easy to control.

The invention discloses an on-line method for measuring the density of acetylene from a outlet of the ethylene device hydrogenation reactor. It chooses some critical variables which impact this kind of density: the quantity of carbon 2 passed into the reactor, the input variables including the quantity of hydrogen and the temperature difference of the reactor, which are used for the soft measure model. The invention makes use of the nerve network model on the DCS system platform of ethylene producing device, collects samples continuously and calculates in time to measure the density of ethine from an exit of the ethylene device hydrogenation reactor by online.

The invention discloses a separation process for preparing low-carbon olefin gas through methanol conversion, aiming at overcoming the defects that products such as high-purity hydrogen, methane, ethane and propane cannot be obtained, dimethyl ether and oxygen and carbon monoxide in flue gas impurities are not effectively removed and the like in the prior art. A carbon monoxide and oxygen removal step is added in the process. Methanol-to-olefin gas with the carbon monoxide and the oxygen being removed passes through six separation tanks and then enters a high-pressure demethanation tower, a deethanization tower, an acetylene hydrogenation reactor, an ethylene rectifying tower, an allylene hydrogenation reactor, a propylene rectifying tower and the like for separation, wherein liquid which comes out from the bottoms of the first five separation tanks sequentially enters the middle-to-upper part of the demethanation tower. By adopting the separation process, polymer-grade ethylene and propylene products can be obtained and products such as high-purity hydrogen, methane, ethane and propane can also be obtained.

The invention discloses a separation method for preparing low-carbon olefin gas through methanol conversion, and aims to solve the problems that products with high purity such as hydrogen, methane, ethane and propane which cannot be obtained in the prior art and oxygen, carbon oxide and the like in dimethyl enther and gas impurities cannot be effectively removed. According to the method, a step of removing the carbon oxide and the oxygen is increased, a methanol prepared olefin gas material flow from which the carbon oxide and the oxygen are removed enters a deethanizing column; the material flow on the top of the deethanizing column flows through an acetylene hydrogenation reactor, six separation tanks, a demethanizing column, an ethylene rectifying column and the like in sequence to separate to obtain ethylene and ethane products; and the material flow at the bottom of the deethanizing column flows through a propyne hydrogenation reactor, a methane stripping column, a propylene rectifying column and the like in sequence to separate to obtain propene and propane products. By using the separation method, polymer grade ethylene and propene products can be obtained, and products with high purity such as hydrogen, methane, ethane and propane can also be obtained.

The invention relates to a method using acetylene hydrogenation to produce ethylene. The method includes the steps of firstly, performing acetylene hydrogenation; secondly, performing gas-liquid separation; thirdly, extracting hydrogen. The method has the advantages that non-polarity organic solvent is added into a reactor with a rotary catalyst bed, so that phase change of the formed liquid film can be achieved, part of reaction heat can be taken away, side reaction occurrence in the acetylene hydrogenation reaction is reduced, bed temperature stability is guaranteed, and catalyst bed temperature runaway is avoided; the solvent recycled by separating reaction products can be reused directly, and the method is simple, and convenient to operate.

The invention relates to a reaction system for preparing ethylene through acetylene hydrogenation. The reaction system is a gas phase-liquid phase two-phase contact reaction system. By means of the system, a traditional solid catalyst can be replaced by a liquid-phase catalyst, so that a traditional gas-solid two phase or gas-liquid-solid three-phase contact reaction is changed into a gas-liquid contact reaction, and coverage of the catalyst activity center by produced green oil is avoided; meanwhile, the hydrogenation activity of the liquid-phase catalyst is under the suitable condition through regulation of proportions of different kinds of complexation metals in the liquid-phase catalyst, the high conversion rate of acetylene is guaranteed, production of the green oil due to self-polymerization of acetylene is avoided, and production of ethane through deep acetylene hydrogenation can be inhibited. The invention further relates to a method for preparing the ethylene with the reaction system. By means of the method, the selectivity of production of the ethylene through acetylene hydrogenation is improved and the yield of the ethylene in product gas is increased.

The invention belongs to the field of coal chemical industry and provides a method for producing ethylene by utilizing pulverized coal. The method comprises the steps of (1) pyrolysis upgrading, (2) pressure swing adsorption and hydrogen extraction, (3) smelting production of calcium carbide, (4) CO conversion decarburization and hydrogen production, (5) acetylene generation, (6) acetylene hydrogenation reaction and (7) cryogenic separation so as to obtain the ethylene and other hydrocarbon products. According to the method, high-quality resources such as blocky coke, semi-coke and anthracite which are high in price are replaced with medium-low-order raw pulverized coal which is low in price, the medium-low-order raw pulverized coal serves as a raw material for producing the calcium carbide, the process energy consumption is low, high value-added tar and pyrolysis gas byproducts are obtained in the pyrolysis process, and the overall economy of the process is improved; a pyrolyzed solid product adopts a hot delivery process, the sensible heat is fully utilized, and the power consumption of a calcium carbide furnace is reduced; hydrogen obtained by the pressure swing adsorption of a pyrolysis gas product and hydrogen obtained by the tail gas conversion of the calcium carbide furnace are used for the acetylene hydrogenation reaction, another product of the calcium carbide furnace reacts with CO2 to generate nano calcium carbonate, and the environmental pollution is reduced.

The invention provides a device and method for producing ethylene through hydrogenation of high concentration acetylene. The device comprises an acetylene hydrogenation reactor, a solvent absorbing tower, and an ethylene condensing device. The structure of the device is simple. An acetylene feed pipeline is connected to the acetylene hydrogenation reactor through an acetylene solvent tank; acetylene is dissolved into a solvent and then introduced into the acetylene hydrogenation reactor; through liquid phase pressurization, the pressure limitation of acetylene is overcome, thus hydrogenation of acetylene can be carried out under a pressure of 1.5 MPaG or more; the acetylene hydrogenation reactor is connected to the solvent absorbing tower, after the acetylene hydrogenation, the obtained gas phase is absorbed by the solvent, the multi-tower rectification separation in the conventional technology is not needed therefore, and the energy consumption is low. The provided device and method can utilize the excess calcium carbide product, greatly relieves the demand on ethylene in our country, and has an important meaning for the sustainable development of acetylene industry of our country, energy saving, and emission reduction.

The invention relates to an acetylene hydrogenation catalyst and a preparation method thereof. The preparation method comprises the following steps: 1) using an alkaline solution to process a carrier, then calcining the carrier to obtain a carrier Z; 2) loading a main active component palladium to the carrier Z to obtain a catalyst semi-finished product; and 3) mixing the catalyst semi-finished product and a solution containing a free-radical scavenger and contacting, and then performing ionizing radiation on the catalyst semi-finished product to reduce palladium to a simple substance. The prepared catalyst has good dispersibility and stability, can obviously increase the catalyst hydrogenation performance, especially increases the capability for removing microscale acetylene from CO and H2-rich gas mixture, and has good industrial application prospect.

A selective hydrogenation method of trace amount of acetylene in a methanol to olefin (MTO) apparatus. In the method, a C2 material from the top of a deethanizing column in the MTO apparatus is fed into an adiabatic bed reactor to perform selective hydrogenation. A Pd-Ni-series catalyst is arranged in the adiabatic bed reactor and is prepared with Al2O3 or a mixture of the Al2O3 with other oxides as a carrier. During preparation of the catalyst, the carrier is combined with hydroxylbipyridine, wherein a metal complex is formed from the hydroxyl bipyridine combined on the carrier and active components. The reaction conditions include: inlet temperature of the adiabatic bed reactor is 45-150 DEG C, reaction pressure is 2.0-3.5 MPa and space velocity is 2000-7000/h. The method, when being used for the selective hydrogenation, improves activity and selectivity of the catalyst significantly and improves the stability of the catalyst. The catalyst has excellent anti-impurity interference capability and is especially used in a trace amount acetylene hydrogenation apparatus being high in impurity content, such as sulfur and arsenic.

The present application discloses a method for preparing a catalyst for hydrogenation of acetylene to ethylene by a high gravity method, which comprises the following steps: dissolving nickel nitrate and zinc nitrate in deionized water, adding hexamethylenetetramine and PVP for ultrasonic treatment Obtain the first solution, then add mesoporous molecular sieve SBA-16 into NMP and mix with the first solution to obtain a mixed solution, then move to a high-gravity rotating packed bed for co-immersion, and centrifuge the mixed solution to obtain a solid substance After drying, it was calcined under a nitrogen atmosphere and naturally lowered to room temperature and then subjected to reduction treatment in a weakly alkaline liquid phase environment to obtain a Ni-Zn/SBA-16 catalyst. The present application also provides an application method of the catalyst prepared by the above method. The catalyst prepared by the above method has a significantly longer cycle life than the catalyst prepared by the traditional method in industrial applications, and can be directly used for the reaction after being reduced by sodium borohydride before use, without the need for high-temperature hydrogen reduction, which is more beneficial to simplify gas-liquid ‑Process flow of solid three-phase catalytic system.

The invention relates to a diacetylene hydrogenation catalyst and mainly solves the technical problems of high catalyst cost and poor stability in the prior art. In the invention, by means of a fixed bed reactor, a material containing the diacetylene and hydrogen are employed as raw materials and are contacted with a catalyst bed layer through the reactor to convert the diacetylene into monoalkene or alkane. The catalyst used in the reactor comprises the following components, on the basis of the weight part of the catalyst: (a) 10-20 parts of metal nickel or an oxide thereof, (b) 0.1-10 parts of at least one element of cerium or lanthanum or an oxide thereof; (c) 0.1-30 parts of zinc or an oxide thereof, (d) 0-2 parts of alkali metal or alkali earth metal, and (e) 38-90 parts of aluminum oxide. The technical scheme solves the technical problem well. The diacetylene hydrogenation catalyst is used in industrial production of high-order acetylene hydrogenation in a device of partially oxidizing natural gas to produce acetylene.

The invention provides a high-dispersion palladium-doped sulfur active carbon catalyst, and a preparation method and application thereof. According to the preparation method, sulfur doping is carriedout by adopting a method of carrying out a hydrothermal process first and then carrying out roasting, and the doped sulfur can more stably exist on the surface of a carbon material by the method. A method for loading noble metal by an impregnation method is simple and convenient, and cost is low. In the high-dispersion palladium-doped sulfur active carbon catalyst, doped sulfur on the surface of the carrier exerts an anchoring effect, so that high dispersion and size regulation and control of palladium nanoparticles can be realized, and the atom utilization rate of a noble metal is effectivelyimproved. Strong interaction between sulfur and the metal ensures high stability of the catalyst, so that the metal nanoparticles are not easily agglomerated or lost in an acetylene hydrogenation reaction process, and the service life of the catalyst is prolonged. The catalyst disclosed by the invention has high selectivity to ethylene in an acetylene hydrogenation reaction, and acetylene can becompletely converted. In addition, the use condition is mild, stability is good, the usage amount of the catalyst is small, and the service life of the catalyst is long.

The invention relates to the field of acetylene hydrogenation and discloses a silver modified raney copper catalyst, a preparation method thereof and a method for selective acetylene hydrogenation of C-4 fraction. The preparation method of the silver modified raney copper catalyst comprises the following steps that copper-aluminum alloy and a solution containing caustic alkali are mixed, and the raney copper catalyst is obtained; and then the raney copper catalyst and a solution containing silver ion are contacted for reacting. The silver modified raney copper catalyst provided by the invention is high in selectivity and catalytic efficiency, and the space velocity can be remarkably improved when the silver modified raney copper catalyst provided by the invention is used for selective acetylene hydrogenation of the C-4 fraction.

The invention discloses a nano-carbon loaded atomic-scale dispersion copper-based catalyst, and a preparation method and application thereof, and belongs to the technical field of catalysts applied toacetylene selective hydrogenation reaction. Acetylene is subjected to hydrogenation to generate ethylene in mixed feed gas through the atomic-scale dispersion copper-based catalyst, and the using temperature of the catalyst is 100-200 DEG C; and copper is dispersed on a nano-carbon material in an atomic-scale mode, compared with a traditional palladium-based carbon material and a commercial palladium catalyst, the nano-carbon loaded atomic-scale dispersion copper-based catalyst can effectively catalyze the acetylene to be converted into the ethylene, and acetylene hydrogenation selectivity isobviously improved. The nano-carbon loaded atomic-scale dispersion copper-based catalyst is low in cost, good in stability performance and not prone to inactivation in the reaction process.

The invention discloses a high-dispersion Pd-Ag alloy catalyst, and belongs to the field of chemical catalysts. Active components of the catalyst are Pd and Ag as auxiliary components, a carrier is Al2O3 or a composite oxide carrier containing the Al2O3, and the catalyst is characterized in that the content of the Pd in the catalyst is 0.01-0.1% by mass, wherein the content of the Ag is 0.03-1.0%,the catalyst is an alloy type bimetallic catalyst, and in the preparation process, a carboxyl-containing compound is adopted to be matched with the Pd for site-specific loading, so that Pd, high dispersion and Pd-Ag alloy formation are facilitated. The method solves the problems of large active metal particle size, non-uniform dispersion, low catalyst active metal utilization rate, unsatisfactoryactivity and selectivity, easy coking of the catalyst and fast deactivation rate caused by the preparation of the catalyst by an impregnation method in the industry at present. The catalyst providedby the invention can be used in the selective hydrogenation process of C2 fraction.

The invention belongs to the field of preparing ethylene through acetylene hydrogenation, and relates to acetylene hydrogenation slurry bed reaction as well as a catalyst separation device and method.The method comprises the following steps of enabling acetylene and hydrogen gas to be subjected to hydrogenation reaction in a hydrogenation reactor which contains a catalyst and a working solution,discharging crude ethylene after reaction, separating a working slurry solution with a membrane separator to obtain a concentrated solution and a clear solution, conveying the concentrated solution directly to the hydrogenation reactor to be recycled, enabling the obtained clear solution to be subjected to gas-liquid separation, and then enabling gas and a fresh working solution to return into thehydrogenation reactor to be continuously used. The hydrogenation reactor is internally provided with an angle gear-shaped gas redistribution device, the gas volume fraction in the working solution can be improved, the radial distribution uniformity of the gas in the reactor is improved, the conversion rate of acetylene and ethylene yield are improved; an airtight membrane separator is adopted toperform solid-liquid separation on the working slurry liquid, the separation process can be guaranteed to be safe and stable, a by-product 'green oil' can be timely extracted, the activity of the catalyst is guaranteed, and the reaction can be promoted to be successfully performed.

The invention relates to a process and a system for preparing ethylene from powdered coal by a two-stage calcium carbide furnace. The process includes (1) two-stage calcium carbide furnace production; (2) carbon monoxide transformation and decarburization for hydrogen production; (3) acetylene generation; (4) acetylene hydrogenation reaction; and (5) cryogenic separation. According to the invention, the upper and lower two-stage calcium carbide furnace is adopted, the pyrolysis process and the calcium carbide production process are combined, the continuous calcium carbide production process and the effective utilization of heat energy are realized, so that the energy consumption of calcium carbide production is effectively reduced; and middle and low order pulverized coal with low costs is adopted as carbon materials, the costs are reduce, the raw material surface area is increased, the reactivity is increased, the calcium carbide smelting temperature is reduced, and the energy consumption is effectively reduced. Tar and pyrolysis gas by-products with high added values are obtained in the pyrolysis process, so that the overall economy of the process is improved, and in addition, the process adopts a liquid solvent to absorb acetylene, avoids the acetylene polymerization explosion hazard, and realizes high pressure reaction, so as to improve the production capacity of the device.