723 results about "Methanation" patented technology

The invention relates to a system for producing methane through biogas reflux coupling microbial electrolysis cell (MEC) enhanced anaerobic digestion and application. A reactor system comprises an MEC anaerobic digestion system and a biogas reflux system. The MEC anaerobic digestion system is provided with a biological anode plate and a biological cathode plate, electroactive microorganisms attached to the biological anode plate convert organic matters into carbon dioxide and generate electrons, and electroactive microorganisms attached to the biological cathode plate convert carbon dioxide into methane; a secondary biogas separation tank is adopted for biogas separation in the biogas backflow system, carbon dioxide in the biogas is more effectively separated out, and the carbon dioxide intermittently flows back to a biological cathode plate of the MEC anaerobic digestion system after being collected. Compared with the prior art, the anaerobic digestion treatment of the organic solid waste is realized, and the in-situ upgrading of the biogas is also realized; and the separated carbon dioxide reflux can be efficiently methanated, so that the emission of the carbon dioxide is reduced, the in-situ treatment of the carbon dioxide is realized, the intermediate links are reduced, and the cost is reduced.

The invention provides a machine learning optimization method and system for a low-temperature high-activity CO2 methanation catalyst, and relates to the technical field of machine learning. The optimization method comprises the following steps: collecting CO2 methanation reaction data, building a machine learning model for hyper-parameter optimization, selecting an optimal model, carrying out interpretable analysis on the optimal model, and screening the catalyst by combining the optimal model with a multi-objective optimization algorithm, so that the machine learning optimization of the CO2 methanation catalyst is realized, and the machine learning can analyze a large amount of data so as to realize the optimization of the CO2 methanation catalyst. The catalyst with high activity and selectivity is rapidly predicted and screened out, and the research and development efficiency is greatly improved; machine learning can reduce experiment times, optimize experiment design, significantly reduce research and development cost, and improve research and development success rate; machine learning can identify and utilize complex chemical and physical data, a catalyst with better performance is designed in a high-precision manner, and the conversion rate and selectivity of converting CO2 into CH4 are improved.

The invention discloses a preparation method of a perovskite type high-temperature-resistant CO2 methanation catalyst, which comprises the following steps: firstly, preparing CaZrO3, then dissolving CaZrO3 powder, a nickel source, a soluble organic fuel and a certain amount of ethylene glycol in deionized water according to a molar ratio of 1: (0.2-0.8): (0.1-0.5), stirring to obtain a dispersion liquid, then putting carrier monoclinic ZrO2 powder in the dispersion liquid, and stirring to obtain the perovskite type high-temperature-resistant CO2 methanation catalyst. The preparation method comprises the following steps: uniformly mixing the raw materials, carrying out ultrasonic treatment for 5-12 hours, heating the obtained mixture at 300-550 DEG C until spontaneous combustion, carrying out high-temperature calcination at 800-900 DEG C for 1-2 hours after flame is extinguished, collecting the calcined product, and carrying out ball milling and granulation to obtain the NiO-CaZrO3 / ZrO2 catalyst with a certain mesh number. According to the preparation method of the catalyst, a solution combustion method is introduced in the preparation process, so that active components of the prepared catalyst are fully dispersed, and further high-temperature calcination is performed on the basis, so that the active components are stably anchored on the surface of the ZrO2 carrier, and the catalytic activity and the stability of the catalyst are improved.

The invention relates to an MOF confinement ruthenium cluster catalyst for methanation of carbon dioxide as well as a preparation method and application of the MOF confinement ruthenium cluster catalyst. The catalyst comprises a carrier and an active component loaded on the carrier, the carrier comprises a metal organic framework containing hydroxyl; the metal organic framework comprises UiO-66 (UiO-66); the active component comprises metal ruthenium; the active component grows in a pore channel of the carrier and forms a metal cluster. The catalyst provided by the invention realizes 100% methane selectivity and 98.4% carbon dioxide (CO2) conversion rate under the conditions of 1 MPa and 220 DEG C, is almost close to thermodynamic limit equilibrium conversion rate (99.4%) and is superior to the currently reported Ru-based CO2 methanation catalyst, and the catalyst shows good catalytic activity and structural stability in the process of continuous reaction for 650 hours. The catalyst provided by the invention has the characteristics of simple preparation method, high metal dispersibility, mild reaction conditions, high conversion rate, good selectivity, excellent stability and the like.

This invention relates to materials, methods, and systems for carbon dioxide (CO2) capture. More specifically, this invention relates to materials, methods, and systems for removing, capturing, separating, and / or adsorbing carbon dioxide (CO2) from a gas mixture. Additionally, this invention relates to materials, methods, and systems for direct air capture (DAC) of CO2 from ambient air. This invention also relates to materials, methods, and systems for direct air capture (DAC) and methanation of CO2 from ambient air.

The invention discloses a carbon dioxide hydrogenation methanation-cracking carbon preparation series method, which comprises the following steps: generating CH4 through a reaction of # imgabs0 # imgabs1 #, and realizing the production of a carbon material by adopting the technologies of condensation separation of CH4 and water vapor, CH4 cracking reaction of # imgabs2 #, cyclic utilization of hydrogen and the like. The process is composed of a carbon dioxide hydrogenation methanation reactor and a methane cracking reactor. In the methanation reactor, CO2 and H2 react under a low-temperature condition to generate CH4 and water vapor; cH4 and water vapor are separated by adopting a compressor condensation separation technology, and the separated CH4 is conveyed to a cracking reactor. In the methane cracking reactor, CH4 is cracked at a high temperature to generate H2 and a carbon nanomaterial, and then H2 is returned to the methanation reactor again. The separation of CH4 and water vapor at a relatively low temperature is realized in the tandem carbonization process through a low-temperature condensation technology; through low-temperature CO2 methanation and CH4 catalytic cracking, the content of CO2 is reduced, a high-quality carbon nanomaterial is obtained, and cyclic utilization of CO2 and H2 is realized.

The invention relates to a preparation method and application of a hydrothermal ammonolysis lignin carbon-based multi-metal catalyst. The Ni-N-C structure is constructed by a hydrothermal nitrogen doping method to enhance the synergistic effect of the catalytic active component and the lignin carbon-based carrier, and Zn is doped to regulate and control the electronic structure of Ni and effectively inhibit hydrogenolysis and methanation of carbon-carbon bonds in the reaction process, so that the catalytic activity of the catalyst and the selectivity of the product are improved. According to the catalyst obtained by the preparation method, the ethanol conversion rate can reach 69.4%, the yield of higher alcohols can reach 50.3%, the selectivity of gas byproducts is only 2.4%, the catalytic effect is good, and the problems that an existing traditional ethanol Guerbet coupling catalyst is low in ethanol conversion rate, tedious in synthesis process, poor in stability and the like can be effectively solved.

The invention discloses a methane-methanol co-production capacity configuration method coupling green electricity hydrogen production and carbon capture technology, which comprises the following steps: obtaining load data and meteorological data in an energy supply area, and obtaining a load curve, an illumination curve and a wind speed curve of the energy supply area through a clustering method; establishing a steady-state model of the equipment according to the operation mechanism of the equipment in the integrated energy system and the coupling relation between the equipment; establishing a mixed integer linear programming model according to the coupling relationship and the steady-state model, and solving the mixed integer linear programming model; and the investment cost of the electrolytic cell is changed, a CPLEX solver is called to solve the mixed integer linear programming model, and capacity configuration optimization results of the methanation equipment and the methanation equipment are obtained. According to the method provided by the invention, a configuration scheme and a scheduling plan of the comprehensive energy system can be scientifically planned, and the capacity of methanation equipment and methanation equipment can be determined in an auxiliary manner on the basis of sensitivity analysis of the investment cost of the electrolytic cell.

The invention discloses a device and a method for promoting methanation of carbon dioxide through temperature oscillation induced by laser scanning. The device comprises a reactor, a laser and a galvanometer, a transparent cover plate is arranged at the top of the reactor, an air outlet is formed in the side surface, and an objective table is arranged in the reactor; a catalyst layer is arranged above the objective table; the catalyst layer is provided with a longitudinally-penetrating gas leading-in hole, a gas flow channel is arranged in the objective table, one end of the gas flow channel is communicated with the gas leading-in hole, and the other end of the gas flow channel is communicated with the gas inlet. Introducing mixed gas containing hydrogen and carbon dioxide into a gas inlet of the reactor, changing the irradiation position of a laser beam emitted by a laser through a galvanometer, and enabling the laser beam to periodically scan and irradiate the catalyst layer to obtain methane. The surface temperature distribution of the catalyst is dynamically regulated and controlled through laser scanning, so that the temperature of a catalytic active site is continuously switched between a high temperature and a low temperature, the thermodynamic limitation of a carbon dioxide methanation reaction can be effectively reduced, and an efficient and stable carbon dioxide methanation process is realized.

The invention relates to the technical field of photocatalytic carbon dioxide reduction, in particular to a Ti < 3 > C < 2 > T < x > MXene / CuInSnS4 composite photocatalyst for photocatalytic carbon dioxide methanation. The reaction yield of photocatalytic reduction of carbon dioxide into methane by using a single CuInSnS4 catalyst is poor. In order to solve the problems, the invention provides the Ti3C2TxMXene / CuInSnS4 composite photocatalyst for photocatalytic carbon dioxide methanation, the Ti3C2TxMXene / CuInSnS4 composite photocatalyst is obtained by compounding Ti3C2TxMXene and CuInSnS4, and the addition of the Ti3C2TxMXene enhances the conductivity of the composite material, inhibits the compounding of photo-induced electrons and holes to a certain extent, and is more beneficial to the proceeding of photocatalytic carbon dioxide reductive methanation reaction.

The invention discloses a hydroxyl-rich ruthenium / titanium dioxide catalyst as well as a preparation method and application thereof, and the preparation method comprises the following steps: step 1, loading a ruthenium precursor on a titanium dioxide carrier by adopting an impregnation method or a deposition-precipitation method, and drying and calcining to obtain a Ru / TiO2 catalyst; and step 2, placing the Ru / TiO2 catalyst in an atmosphere environment containing water vapor or forming a physical adsorption water film on the surface of the Ru / TiO2 catalyst, and performing ultraviolet irradiation treatment to obtain the Ru / TiO2 catalyst. According to the method, water is physically adsorbed through ultraviolet light dissociation, hydroxyl is directly generated on the surface of Ru / TiO2 in an in-situ mode, the method is easy to operate, complex liquid phase treatment is not needed, and the stability of the generated hydroxyl under the subsequent high-temperature gas-solid phase hydrogen-rich reaction condition is obviously superior to that of hydroxyl introduced through a traditional method. The stable hydroxyl enriched on the surface serves as an effective Lewis base site and cooperates with a Ru active site, adsorption and activation of CO2 molecules are remarkably promoted, and therefore the catalytic activity of the CO2 methanation reaction is greatly improved.

The present invention discloses a monatomic fluid driven carbon dioxide methanation conversion system and a method of use, comprising an absorption device and a desorption conversion device, wherein the liquid outlet of the absorption device is connected to the first inlet of a heat exchanger via a first pump, the first outlet of the heat exchanger is connected to the inlet of a desorption conversion device, the liquid outlet of the desorption conversion device is connected to the second inlet of the heat exchanger via a second pump, and the second outlet of the heat exchanger is connected to the liquid inlet of the absorption device via a cooler. The use of monatomic fluid as a solvent in the present invention can not only generate electric charge and effectively solve the problem of high energy consumption caused by desorption of CO2 due to thermal desorption, but also couple thermal and electric charge effects to greatly break through the high energy consumption bottleneck caused by reaction temperature faced by traditional thermal desorption, and greatly reduce the reaction energy barrier and reaction heat. During the desorption process, the charge effect of the molecules in the solvent combined with CO2 can promote the realization of efficient methanation conversion of CO2.

The invention provides a nickel-based supported catalyst, a preparation method and application thereof, and a carbon dioxide methanation method, and belongs to the technical field of catalysts. The nickel-based supported catalyst provided by the invention comprises a carrier and nickel oxide supported on the surface and in pore channels of the carrier, the carrier comprises carbonate and / or citrate. The carbonate and / or citrate are / is used as the carrier, the nickel-based supported catalyst is synthesized by adopting a solution combustion method, the nickel-based supported catalyst has larger specific surface area and smaller particle size, the nickel oxide and the carrier have a stronger mutual combination effect, the nickel-based supported catalyst has excellent stability, and CO2 methanation can be catalyzed for a long time under a low-temperature condition. The nickel-based supported catalyst is combined with the low-temperature plasma, so that CO2 methanation can be catalyzed at normal temperature and normal pressure, and the catalyst has high CO2 conversion rate and CH4 selectivity.

The invention belongs to the technical field of alkane processing, and particularly relates to a process for preparing isopentene by dehydrogenation of isopentane, a catalyst and a tert-amyl alcohol preparation process. The process for preparing isopentene by dehydrogenation of isopentane comprises an isopentane dehydrogenation device and an isopentene separation device, in the isopentane dehydrogenation device, a dehydrogenation reactor is a fixed bed adiabatic reactor and is filled with a Pt-Sn-K / alumina type alkane dehydrogenation catalyst, the catalyst has hydromethanation performance under the CO2-containing dehydrogenation reaction condition, and the arrangement and operation of a dehydrogenation reactor group comprise a mode A, a mode B or a mode C; the isopentene separation device comprises a cooling separation system, a pressure swing adsorption separation system and an optional rectification system. The tert-amyl alcohol is further prepared from isoamylene under the conditions of a fixed bed hydration reactor, ethylene glycol monobutyl ether and other solvents, and the tert-amyl alcohol product is obtained through separation. The process is superior to the prior art on the whole, and has certain application prospects.

The invention discloses a coal-fired flue gas CO2 capture and conversion utilization integrated system and method.The system comprises a first reactor and a second reactor which are arranged in parallel, and the first reactor and the second reactor are both filled with capture catalytic materials; the first reactor and the second reactor are both connected with an H2 storage tank, an N2 storage tank, a CH4 storage tank and a flue gas conveying pipeline, and the first reactor and the second reactor alternately carry out CO2 capture and CO2 conversion and utilization processes; the reactor filled with the trapping catalytic material is adopted, so that integration of CO2 trapping and conversion utilization can be realized, and the problems of high energy consumption and system complexity in CO2 release, separation, storage and conversion processes when CO2 trapping and conversion are carried out in two steps are solved; two reactors are arranged to alternately carry out CO2 capture and CO2 conversion and utilization processes, so that the continuous operation of the whole system is realized; and meanwhile, the system can realize the conversion and utilization of two kinds of CO2, namely methanation and dry reforming, so that the practicability of the system is improved.

To provide a methane producing apparatus that can reduce an amount of methanation catalyst.SOLUTION: A methane producing apparatus 1 produces methane by allowing raw material gas to pass through a first reactor 10 and a second reactor 20. Each reactor comprises: a heating part 112 which heats raw material gas to an optimal temperature; a reaction part 113 which allows raw material gas to perform methanation reaction by a catalyst maintained at an optimal temperature; a cooling part 114 which cools reaction gas; and a heat medium flow channel 13 which is a flow channel arranged in a state of surrounding the parts, and through which heat medium is flown. A heat medium in a first temperature zone which has been supplied to the heat medium flow channel performs heat exchange with reaction gas of the cooling part 114 to enter a second temperature zone higher than the first temperature zone, performs heat exchange with a catalyst of the reaction part 113 to enter a third temperature zone higher than the second temperature zone, and performs heat exchange with raw material gas of the heating part 112 to enter a fourth temperature zone lower than the third temperature zone and higher than the first temperature zone.SELECTED DRAWING: Figure 1

Captured carbon dioxide is converted into ultra-high purity hydrocarbons, particularly methane. A gas stream containing carbon dioxide is fed to a reactor containing both sorbent and catalyst, until the sorbent portions are substantially saturated with carbon dioxide; non-sorbed species are removed from the first reactor via vacuum and / or purge cycles with high-purity gas; hydrogen gas is introduced to the first reactor to a pressure above ambient; reactor temperature is raised to facilitate desorption of carbon dioxide; and the carbon dioxide is catalytically transformed with the hydrogen gas into methane by recirculating the gas through the reactor. Carbon dioxide adsorption and desorption occur within the sorbent portions, while methanation takes place on the catalytic portions assisted by the sorbent at a temperature substantially consistent with the desorption. Downstream upgrading steps may remove or reduce impurities to produce ultra-high purity methane for chemical vapor deposition or other processes.

The invention relates to a preparation method of a nano-catalyst based on a bimetallic organic framework material, and a product and application thereof, the preparation method comprises the following steps: (1) mixing 1, 4-terephthalic acid and N, N-dimethylformamide to obtain a solution A, mixing the solution A with formic acid, ceric ammonium nitrate and zirconyl nitrate to synthesize a bimetallic organic framework material Ce / Zr-UiO-66; and (2) carrying out impregnation and reduction on a metal salt precursor to obtain the nano-catalyst based on the bimetallic organic framework material. According to the method disclosed by the invention, the Zr site part is replaced by Ce in the Zr6O8 cluster at the UiO-66 node through one-pot synthesis, and the anchoring of the ultra-small nano metal is realized; the catalyst realizes catalysis of carbon dioxide hydrogenation methanation under mild conditions, and shows the advantages of high methane selectivity, high conversion rate and long-time stability.

The invention relates to a nickel-based methanation catalyst taking a mesoporous molecular sieve SBA-16 as a carrier and application of the nickel-based methanation catalyst in carbon dioxide hydrogenation. The catalyst is prepared by preparing a mesoporous molecular sieve SBA-16 as a carrier, dissolving nickel salt in a solvent, adding an additive, and combining the SBA-16 carrier with nickel metal by an impregnation method. The catalyst has high activity and good stability, especially has excellent performance in a CO2 methanation reaction, can realize high CO2 conversion rate and high CH4 selectivity at a low temperature, and is suitable for reaction conditions with a temperature of 200-400 DEG C and a pressure of normal pressure to 5.0 MPa. The preparation method of the catalyst is simple, does not need precious metal, and has potential industrial application prospects.

The invention discloses a zero-carbon glass kiln process. A system required by the process comprises a photovoltaic power generation device, an air separation device, a water electrolysis hydrogen production device, a mixer, a methanation device, a waste heat boiler I, a reforming device, a glass kiln, a waste heat boiler II and a dust removal and desulfurization device. Green oxygen, green nitrogen and green hydrogen are produced through green electricity driving; the flue gas of the glass kiln is cyclically enriched into high-concentration carbon dioxide (95.0 v% or above), the high-concentration carbon dioxide and green hydrogen are subjected to a methanation reaction to produce methane, and the methane, the carbon dioxide and water vapor are subjected to a reforming reaction to produce carbon monoxide and hydrogen; carbon monoxide and hydrogen are used as fuel of the glass kiln, green oxygen and carbon dioxide are mixed to form carbon-based oxygen-enriched combustion which is used as a combustion improver of the glass kiln, carbon-based oxygen-enriched combustion of the glass kiln is carried out, and redundant carbon dioxide is sold. According to the invention, the purposes of greenness, energy conservation, almost no nitrogen oxide and zero carbon are realized.

The invention relates to the technical field of methanol catalysts, in particular to a catalyst for improving selectivity of methanol prepared from methane through proton regulation and a preparation method. The preparation method comprises the following steps: S1, adding Zn (NO3). 6H2O into deionized water to prepare a solution, adding a sodium hydroxide solution, washing and drying to obtain a product; s2, adding a product in the step S1 into hydrogen peroxide, and then washing and drying; s3, putting a product in the step S2 into ethanol, adding APTES, washing and drying; s4, putting a product obtained in the step S3 into deionized water containing DPA-MOF, and carrying out heating reaction in a closed environment; s5, adding a sodium hydroxide solution into the solution cooled in the step S4, and washing and drying a product; and S6, dispersing the product obtained in the step S5 into a deionized water solution of ammonium nitrate, drying and calcining. The catalyst prepared by the invention has efficient selective catalysis on methanol through efficient proton affinity regulation and control.

The embodiment of the invention discloses system control equipment for a methanation reaction system. The equipment comprises a methanation reaction system, a distributed control system and an advanced control system, the distributed control system is used for collecting the real-time flow value of the raw material gas passing through the flow control main valve and the flow control slave valve, the temperature value of the first gas passing through the first reactor and the temperature value of the second gas passing through the second reactor; sending the feed gas real-time flow value, the first gas temperature value and the second gas temperature value to an advanced control system; and the advanced control system is used for determining the valve opening degrees of the flow control main valve and the flow control slave valve according to the real-time flow value of the raw material gas, determining the valve opening degree of the distribution valve according to the second gas temperature value, and determining the valve opening degrees of the anti-surge valve and the guide vane valve according to the first gas temperature value. By applying the scheme provided by the embodiment of the invention, the methanation reaction system can be accurately controlled, so that the quality of finished gas is ensured to meet the process requirements.

The invention relates to a preparation method and application of a Ni-CeO2 catalyst. The method comprises the following steps: (1) dissolving nickel precursor salt, cerium oxide precursor salt and citric acid monohydrate in deionized water to prepare a mixed solution; (2) refluxing, stirring and aging the mixed solution in a water bath at 50-90 DEG C for 1-5 hours; (3) performing rotary evaporation on the aged sol to obtain gel; after drying, grinding into powder, and calcining at 300-500 DEG C to obtain a NiO-CeO2 precursor; (4) reducing the obtained NiO-CeO2 precursor, so as to obtain a Ni-CeO2 catalyst A; the prepared Ni-CeO2 catalyst is used for methanation reaction. The catalyst has excellent carbon dioxide conversion rate and methane selectivity at low temperature, and meanwhile, the catalyst has long-period stability and good carbon deposition resistance.

The invention provides a ruthenium-based carbon dioxide hydrogenation catalyst based on MoS2 as well as a preparation method and application of the ruthenium-based carbon dioxide hydrogenation catalyst. The carbon dioxide hydrogenation catalyst comprises silicon dioxide, ruthenium and molybdenum disulfide, and the ruthenium and the molybdenum disulfide are loaded on the silicon dioxide. Therefore, in the carbon dioxide hydrogenation catalyst, the molybdenum disulfide is used as an auxiliary agent, so that the generation of methane (CH4) can be remarkably inhibited while a high CO2 conversion rate is maintained, the reversion of a product from CH4 leading to carbon monoxide (CO) leading is realized, and the inherent core defects that an existing Ru-based CO2 hydrogenation catalyst is too high in methanation activity, low in CO selectivity and difficult to consider activity-selectivity at the same time are overcome.

The invention belongs to the technical field of catalyst development, and relates to a cerium oxide-loaded non-noble metal catalyst for a carbon dioxide methanation reaction and a preparation method of the cerium oxide-loaded non-noble metal catalyst. The method comprises the following steps: firstly, obtaining a cerium oxide carrier through a hydrothermal reaction, secondly, impregnating non-noble metal nitrate serving as a precursor on the cerium oxide carrier through an impregnation method, and carrying out ultrasonic treatment, drying, calcining and other steps to obtain the cerium oxide supported non-noble metal catalyst. The prepared catalyst is low in cost and has excellent carbon dioxide methanation catalytic activity. By controlling the loading capacity and the loading type of the non-noble metal, a multi-site synergistic effect is realized, more active sites are exposed, and finally, the catalytic performance of the cerium oxide loaded non-noble metal catalyst for catalyzing methanation of carbon dioxide at low temperature is improved.

The invention provides an aluminum-doped NiCoCe catalyst, a preparation method thereof and application of the aluminum-doped NiCoCe catalyst in low-temperature CO2 hydrogenation methane preparation reaction, the preparation method comprises the following steps: (1) dissolving nickel nitrate, cobalt nitrate, cerium nitrate, aluminum nitrate and an alkaline precipitator in deionized water, and fully stirring the solution at room temperature to obtain a solution A; (2) putting the solution A into a reaction kettle, and crystallizing the mother liquid at a constant temperature for a certain time to obtain a solid-liquid mixture B; (3) centrifuging and washing the solid-liquid mixture B in the step (2) to obtain a precipitate C; (4) drying the precipitate C in the step (3) to obtain a precursor D; and (5) reducing and passivating the precursor D in the step (4) to obtain the catalyst. The catalyst prepared by the invention effectively solves the problem of low CO2 conversion rate in low-temperature CO2 methanation reaction, lattice distortion is promoted by introducing the Al element, the migration ability of lattice oxygen is increased, and the formation of a large number of oxygen vacancies is beneficial to improving the oxidation-reduction property of the catalyst.

The invention relates to the technical field of organic solid waste treatment, in particular to a process system for hydrogen production and co-production of biological natural gas from biological crude synthesis gas, which comprises a purification unit, a hydrocarbon regulation unit, an acid removal unit, a methane upgrading unit, a hydrogen recycling and purifying unit and a methane recycling and purifying unit which are connected in sequence. The purification unit is used for removing impurities through pre-impurity removal, compression, dry-process impurity removal and wet-process desulfurization to produce purified synthesis gas and sulfur; the hydrocarbon adjusting unit is pressurized through a centrifugal compressor and adjusts the hydrogen-carbon ratio; the acid removal unit is used for removing acid gas and organic sulfur; the methane upgrading unit is used for converting CO / CO2 into methane through methanation reaction; and the recycling unit purifies hydrogen through pressure swing adsorption and recycles methane by using a membrane separation technology to produce biogas. The problems of low purity and insufficient raw material utilization rate of the traditional process are solved through the circulation process, the co-production of high-purity hydrogen and biogas is realized, and the additional value of resources is improved.

The invention relates to the technical field of methanation reaction catalysts, in particular to a supported catalyst for methanation of carbon dioxide and a preparation method thereof.According to the preparation method, firstly, a nickel-doped cerium dioxide carrier is prepared through a urea method, and then a metal nickel nano-catalyst is supported on the carrier through an impregnation method; the preparation process is simple, the operation repeatability is high, and the method is suitable for large-scale industrial production; according to the supported catalyst for methanation of carbon dioxide, provided by the invention, the nickel-doped improved cerium dioxide is adopted as the carrier, and the oxygen vacancy concentration in the cerium dioxide carrier is greatly improved through the nickel doping amount, so that the activation and conversion of CO2 are promoted, and the problems of low activity and poor stability of the existing nickel-based catalyst for methanation of CO2 are effectively solved.

The invention discloses a metal oxide nano island modified nickel-based catalyst for low-temperature CO2 methanation as well as a preparation method and application of the metal oxide nano island modified nickel-based catalyst, and belongs to the technical field of preparation of low-temperature CO2 methanation catalysts. The catalyst comprises a metal nickel salt and a metal oxide nano island, the particle size of the metal nickel salt is 5-20 nm, and the particle size of the metal oxide nano island is 2-10 nm. The invention further discloses a preparation method and application of the metal oxide nano island modified nickel-based catalyst for low-temperature CO2 methanation. According to the novel catalyst, CO2 can be converted into CH4 under the mild conditions of 160 DEG C and 0.1 MPa, the CO2 conversion rate is close to 90% at 220 DEG C, the CH4 selectivity is 100%, and the reaction temperature is reduced by 100 DEG C compared with that of a traditional nickel-based catalyst.

The invention discloses a reverse shift catalyst capable of inhibiting methanation side reaction under the process condition of higher pressure and a preparation method of the reverse shift catalyst, the catalyst comprises the following effective component: iron accounting for 40-80% (weight percentage) of the total amount of the catalyst in terms of Fe2O3, an auxiliary agent for inhibiting methanation side reaction is added, and the preparation method of the catalyst is a mixing and kneading method. According to the present invention, the auxiliary agent for inhibiting the methanation side reaction is added under the reverse transformation process condition, such that the methane generation amount of the catalyst under the reverse transformation high pressure process condition is significantly reduced, the selectivity of the CO2 reverse transformation reaction is improved, the hydrogen consumption is reduced, and the new requirement of the national green dual-carbon development is met.