Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
  • B01D53/34—Chemical or biological purification of waste gases
  • B01D53/46—Removing components of defined structure
  • B01D53/48—Sulfur compounds
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
  • B01D53/34—Chemical or biological purification of waste gases
  • B01D53/46—Removing components of defined structure
  • B01D53/62—Carbon oxides
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
  • B01D53/34—Chemical or biological purification of waste gases
  • B01D53/74—General processes for purification of waste gases; Apparatus or devices specially adapted therefor
  • B01D53/81—Solid phase processes
  • B01D53/82—Solid phase processes with stationary reactants
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
  • B01D53/34—Chemical or biological purification of waste gases
  • B01D53/74—General processes for purification of waste gases; Apparatus or devices specially adapted therefor
  • B01D53/86—Catalytic processes
  • B01D53/8603—Removing sulfur compounds
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
  • B01D53/34—Chemical or biological purification of waste gases
  • B01D53/74—General processes for purification of waste gases; Apparatus or devices specially adapted therefor
  • B01D53/86—Catalytic processes
  • B01D53/864—Removing carbon monoxide or hydrocarbons
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M8/00—Fuel cells; Manufacture thereof
  • H01M8/06—Combination of fuel cells with means for production of reactants or for treatment of residues
  • H01M8/0662—Treatment of gaseous reactants or gaseous residues, e.g. cleaning
  • H01M8/0668—Removal of carbon monoxide or carbon dioxide
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M8/00—Fuel cells; Manufacture thereof
  • H01M8/06—Combination of fuel cells with means for production of reactants or for treatment of residues
  • H01M8/0662—Treatment of gaseous reactants or gaseous residues, e.g. cleaning
  • H01M8/0675—Removal of sulfur
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D2251/00—Reactants
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D2255/00—Catalysts
  • B01D2255/20—Metals or compounds thereof
  • B01D2255/209—Other metals
  • B01D2255/2092—Aluminium
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D2256/00—Main component in the product gas stream after treatment
  • B01D2256/16—Hydrogen
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D2256/00—Main component in the product gas stream after treatment
  • B01D2256/24—Hydrocarbons
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D2257/00—Components to be removed
  • B01D2257/30—Sulfur compounds
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D2257/00—Components to be removed
  • B01D2257/50—Carbon oxides
  • B01D2257/502—Carbon monoxide
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
  • Y02A50/00—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE in human health protection, e.g. against extreme weather
  • Y02A50/20—Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02C—CAPTURE, STORAGE, SEQUESTRATION OR DISPOSAL OF GREENHOUSE GASES [GHG]
  • Y02C20/00—Capture or disposal of greenhouse gases
  • Y02C20/40—Capture or disposal of greenhouse gases of CO2
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
  • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
  • Y02E60/30—Hydrogen technology
  • Y02E60/50—Fuel cells

Definitions

• the present invention relates to a method for removing carbon monoxide and / or gaseous sulfur compounds from hydrogen gas and / or aliphatic hydrocarbons, preferably at low temperatures, with the aid of complex metal-aluminum hydrides.
• Hydrogen is the most important energy carrier for fuel cells.
• the polymer electrolyte fuel cell has gained importance as a low-temperature fuel cell in recent years.
• the polymer electrolyte fuel cell (“Polymer Electrolyte Fuel Cell" - PEFC - colloquially mostly called PEM - works at operating temperatures below 100 ° C.
• a characteristic feature of the polymer electrolyte fuel cell is the thin, gas-tight, proton-conducting, solid polymer membrane as the electrolyte. Acid groups are integrated into this plastic skin, ie the protons diffuse through the membrane, as in all acidic cells, from the anode to the cathode, where they recombine together with the oxygen ions to form water.
• the water content of currently available perfluorinated polymer membranes eg made from NAFION ®
• the electrical contact from the electrodes to the bipolar plates takes place via metallic or carbon-containing current conductors.
• the noble metal catalysts and electrolytes used require a comparatively high level of fuel gas purity. Only H 2 can be used as the fuel gas.
• the oxidizing agent is 0 2 , and unlike other fuel cells, air operation is also possible; this significantly expands the application possibilities of the PEFC.
• carbon monoxide (CO) is only tolerated in very small quantities of ⁇ 0.2 ppm, since it acts as a catalyst poison just like sulfur compounds.
• Hydrogen hardly occurs in pure form on earth and is therefore generated with energy expenditure.
• a manufacturing process often used in industry is the steam reforming of natural gas or hydrocarbons from other sources. The hydrogen is gradually withdrawn from the hydrocarbon chains using the various reforming processes. By-products include Carbon monoxide, nitrogen oxides and sulfur dioxide. If the gas produced during the reforming is in a low-temperature
• the fuel cell If the fuel cell is to be conducted, it must first be cleaned of carbon monoxide. For thermodynamic reasons, carbon monoxide is also formed during reforming and, like sulfur compounds, is a poison for the catalysts of the fuel cell. In the processes in the prior art, cleaning is carried out in the so-called water-gas shift reactor and in the reactor for preferential oxidation carried out. However, these processes are rather expensive and there is therefore a need for a simplified process for the production of hydrogen gas or gaseous aliphatic hydrocarbons from which catalyst poisons such as CO or sulfur compounds have been removed.
• the invention relates to a method for removing carbon monoxide and / or gaseous sulfur compounds from a gas containing carbon monoxide and / or gaseous sulfur compounds, in which the gas, selected from hydrogen gas and / or one or more gaseous aliphatic hydrocarbons or a mixture thereof, in a
• the reaction can be carried out in a vessel designed as a reaction vessel for a batch reaction or, preferably, as a reaction vessel for a continuous reaction into which the gas to be purified is introduced, brought into contact with the complex metal-aluminum hydride and after the reaction is passed out of the reaction vessel.
• This makes it possible to design the reaction vessel in the form of a permeable filter unit which is filled with one or more complex metal-aluminum hydrides of the formulas I to III.
• Such a through-flow filter unit can advantageously be used as a filter cartridge, in particular in front of fuel cells, in order to To protect the catalyst from the catalyst poisons in the hydrogen gas used.
• a through-flow filter unit can have an indicator display, which shows the degree of loading of the filter unit and allows timely replacement.
• the invention also relates to a fuel cell with at least one such filter unit according to the invention through which a flow can flow.
• the gas flow can be diverted depending on the degree of loading of a first filter unit to at least one second filter unit arranged "parallel" in the gas flow, so that continuous operation of the fuel cell is made possible.
• the first filter unit can be subjected to a step for recycling the complex metal hydride.
• Me stands for one or more arbitrary alkali or alkaline earth metals from the periodic table of the elements.
• the complex hydride used can be fully or only partially dehydrated. According to the invention, dehydrogenated is understood to mean that the hydrogen bound to the metal has been removed from the metal hydride by measures for dehydrogenation such as, for example, heating up to the decomposition temperature.
• the aforementioned complex hydrides can be mixed with one or more metals as metal compounds such as metal salts, for example metal halides, or also as metal in particle form, in order to increase the reactivity of the metal-aluminum hydrides.
• metals are transition metals from groups 3, 4, 5, 6, 7, 8, 9, 10, 11, in particular Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Y, Zr, Nb, Mo, La, Ce, Pr and Nd, or alloys or mixtures of these metals with one another or with aluminum, or compounds of these metals, for example as a metal salt such as metal halide, in the form of very small particles with a high degree of distribution, for example with particle sizes approx.
• metals such as Ti, Zr, Sc, Y, and rare earth metals.
• the metals can be produced from different precursors directly by reduction in-situ with the complex metal hydride or ex-situ by various reduction processes. In-situ production is preferred.
• Additives such as carbon (graphite, spheroidal carbon, activated carbon) in particle form with a particle size of 10 nm to 1000 nm or metal powders such as Al powder with particle sizes of 10 nm to 1000 nm can be added to the complex hydride or the mixture of metal and complex hydride in order to achieve a good distribution of catalyst and complex hydride on the surface of the particles.
• the complex hydrides described above, which have been partially oxidized, can also be used. The oxidation occurs through contact with oxygen (air), for example simply in air.
• the CO-containing hydrogen gas is passed in a reactor over the metal hydride powder composed of complex hydride and catalyst in flow or also in batch operation and is thus brought into contact with the latter.
• the contact can also take place in a fluidized bed reactor or in a closed reaction vessel such as in an autoclave.
• the flow rates of the CO-containing hydrogen gas are selected in a continuous operation so that a complete reaction and adsorption on the complex metal hydride takes place, and are usually 1.5 L / hg (complex metal hydride).
• the pressure in the reaction vessel is not critical and can be in the range of normal pressure from about 0.1 to 15 MPa.
• the reaction temperature is generally between -20 ° and 250 ° C. The invention is explained further with reference to the attached FIGS. 1 to 5 and the production examples.
• Figures 1 to 4 show the course of tests for the method according to the invention in comparison with a method not according to the invention.
• FIG. 4 illustrates the reusability of a flow tube filled with a complex metal-aluminum hydride used in the process according to the invention, which was subjected to a step to remove the adsorbed carbon monoxide, for example under the action of ambient air on the complex metal-aluminum hydride.
• FIG. 5 shows the test apparatus and serves to explain the test method.
• the test apparatus consists of the absorption tube 4, filled with a complex aluminum hydride, the storage vessel 5 for the gas mixture used, a mass flow meter 6, a vacuum pump 7 and an IR spectrometer 8 to control the CO concentration in the gas mixture.
• the individual work processes can be carried out under inert conditions via valves 1, 2 and 3.
• valve 2 Before starting the measurement, the entire apparatus is evacuated through valve 2 with valves 1 and 3 closed. Valve 2 is then closed and the apparatus is filled with an inert gas via valve 3. The gas mixture is supplied with valves 1 and 3 open, the gas flow being adjusted to the required amount of gas with the aid of the mass flow controller 6. After the gas mixture has flowed through the absorption tube 4, the CO concentration is determined with the aid of the IR spectrometer 8.
• a reduction in the absorption capacity of the complex aluminum hydrides when removing impurities from hydrogen gas can be made visible in a simple manner by means of a color reaction in a window cartridge in the direction of flow after the absorption tube 4 in front of the valve 1 and thus controlled.
• the released iodine causes a discoloration of the carrier material on which the color reaction takes place. This enables visual observation and control of a decreasing absorption capacity, and the absorption tube can be replaced in good time.
• Two or more absorption tubes 4 are preferably arranged in parallel in the direction of flow, and when the absorption capacity decreases, the gas flow can be switched from one to another absorption tube 4.
• FIG. 4 illustrates the reusability of a flow tube filled with a complex metal-aluminum hydride used in the method according to the invention, which was subjected to a step for removing the adsorbed carbon monoxide, for example under the action of ambient air on the complex metal-aluminum hydride.
• the gas concentration was determined with the aid of a gas-filled optopneumatic detector.
• the particle sizes were determined either by laser diffraction or, in the case of very small particles, by means of TEM analyzes (transmission electron microscopy). Manufacturing example
• Na 3 AlH 6 is ground with TiCl 3 (2-4 mol%) and, if necessary, other additives in a ball mill.
• the material obtained in this way is used to remove CO from hydrogen gas.
• Other impurities such as C0 2 , H 2 O and S compounds can also be eliminated from hydrogen gas using this process.

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• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Environmental & Geological Engineering (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Biomedical Technology (AREA)
• Analytical Chemistry (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Health & Medical Sciences (AREA)
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• Life Sciences & Earth Sciences (AREA)
• Sustainable Development (AREA)
• Sustainable Energy (AREA)
• Electrochemistry (AREA)
• Solid-Sorbent Or Filter-Aiding Compositions (AREA)
• Catalysts (AREA)
• Fuel Cell (AREA)
• Hydrogen, Water And Hydrids (AREA)
• Gas Separation By Absorption (AREA)

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• 2019
  • 2019-07-30 DE DE102019211379.6A patent/DE102019211379A1/de not_active Withdrawn
• 2020
  • 2020-07-26 CA CA3145150A patent/CA3145150A1/en active Pending
  • 2020-07-26 KR KR1020227006303A patent/KR20220040477A/ko active Search and Examination
  • 2020-07-26 US US17/631,751 patent/US20220266195A1/en active Pending
  • 2020-07-26 WO PCT/EP2020/071066 patent/WO2021018809A1/de unknown
  • 2020-07-26 JP JP2022505427A patent/JP2022543750A/ja active Pending
  • 2020-07-26 EP EP20746946.1A patent/EP3993896A1/de active Pending
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