An H.sub.2-rich fuel gas stream can be advantageously produced by reforming a hydrocarbon/steam mixture in to produce a reformed stream, followed by cooling the reformed stream in a waste-heat recovery unit to produce a high-pressure steam stream, shifting the cooled reformed stream a first shifted stream, cooling the first shifted stream, shifting the cooled first shifted stream to produce a second shifted stream, cooling the second shifted stream, abating water from the cooled second shifted stream to obtain a crude gas mixture stream comprising H.sub.2 and CO.sub.2, and recovering a CO.sub.2 stream from the crude gas mixture stream. The H.sub.2-rich stream can be advantageously combusted to provide thermal energy needed for residential, office, and/or industrial applications including in the H.sub.2-rich fuel gas production process. The H.sub.2-rich fuel gas production process can be advantageously integrated with an olefins production plant comprising a steam cracker.

Methods and systems for reducing greenhouse gas emissions, including producing a waste gas stream comprising form greater than 0 vol % to less than 20 vol %, inclusive, carbon dioxide, pre-concentrating the waste gas stream to increase a concentration of carbon dioxide, producing a concentrated byproduct stream comprising more than 40 vol %, dissolving carbon dioxide contained in the concentrated byproduct stream in water, producing a dissolved byproduct stream and an undissolved byproduct stream, injecting the dissolved byproduct stream or a portion thereof into a reservoir containing mafic rock, and allowing components of the dissolved byproduct stream to react in situ with components of the mafic rock to precipitate and store components of the byproduct stream in the reservoir.

Methods and systems for reducing greenhouse gas emissions, including producing a waste gas stream comprising form greater than 0 vol % to less than 20 vol %, inclusive, carbon dioxide, pre-concentrating the waste gas stream to increase a concentration of carbon dioxide, producing a concentrated byproduct stream comprising more than 40 vol %, dissolving carbon dioxide contained in the concentrated byproduct stream in water, producing a dissolved byproduct stream and an undissolved byproduct stream, injecting the dissolved byproduct stream or a portion thereof into a reservoir containing mafic rock, and allowing components of the dissolved byproduct stream to react in situ with components of the mafic rock to precipitate and store components of the byproduct stream in the reservoir.

The invention provides a process for separating hydrogen from a gaseous feed stream in a polymerisation process, comprising the steps i) polymerising an olefin monomer and optionally at least one olefin comonomer, in the presence of a solvent optionally in the presence of hydrogen, so as to form a polymerisation reaction mixture comprising a polyolefin polymer, unreacted monomer(s), solvent and hydrogen; ii) separating said polyolefin polymer from said unreacted monomer(s), solvent and hydrogen; iii) feeding said unreacted monomer(s) and hydrogen to a condenser so as to form said gaseous feed stream; iv) contacting said gaseous feed stream with a hydrogen separating membrane so as to form a hydrogen-rich gaseous stream and a hydrogen-lean gaseous stream.

A method of using a feedstock gas reactor is described. A hydrocarbon, such as methane, is chemical decomposed in the feedstock gas reactor using heat of combustion generated from the combustion of a combustible gas. A mixed product stream is extracted from the feedstock gas reactor. The mixed product stream comprises hydrogen, carbon, and water. At least a portion of the one or more combustion product gases are vented from the combustion chamber. At least some of the carbon is activated using the vented one or more combustion product gases. At least some of the activated carbon is recycled to the feedstock gas reactor.

The present disclosure relates to a hydrogen gas production method including: a first step of generating a mixed gas containing hydrogen and carbon dioxide from a hydrogen storage agent by dehydrogenation reaction using a catalyst in a reactor; a second step of purifying the generated mixed gas to acquire a gas having a high hydrogen concentration; a third step of separating a solution in the reactor into a solution enriched with the catalyst and a permeate using a separation membrane unit; and a fourth step of supplying the solution enriched with the catalyst to the reactor for reusing in the first step.

A membrane is described for purifying or separating hydrogen from a multi-component gas stream such as syngas. This membrane uses a molecular pre-treatment, a transition metal, fluorine containing polymer, carbon fibers and carbon matrix sintered on a supportive screen. The membrane may be a bilayer membrane comprised of a layer containing high surface area carbon and another layer containing lower surface area carbon. Methods for purifying hydrogen are also described.

A reforming method may include: reforming a hydrocarbon with steam plasma to generate a first synthetic gas, which includes hydrogen and carbon dioxide, from the hydrocarbon; cooling the first synthetic gas to a predetermined temperature, removing water vapor included in the first synthetic gas, and separating hydrogen from the first synthetic gas; reforming the first synthetic gas, from which hydrogen is separated, and a hydrocarbon with steam plasma to generate hydrogen, and generating a second synthetic gas in which carbon dioxide is decreased; and cooling the second synthetic gas to a predetermined temperature, removing water vapor included in the second synthetic gas, and separating hydrogen from the second synthetic gas.

A high selectivity and high CO.sub.2 plasticization resistant polymer comprises a plurality of repeating units of formula (I) for gas separation applications. The polymer may be synthesized from a superacid catalyzed poly(hydroalkylation) reaction.

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Membranes made from the polymer and gas separation processes using the membranes made from the polymer are also described.

Provided are a hydrogen purification device and a hydrogen purification method whereby hydrogen having a high purity can be purified at a high yield from a starting gas. The hydrogen purification device comprises: a starting gas source that supplies a starting gas, said starting gas containing hydrogen molecules and/or a hydride, to a discharge space; a plasma reactor that defines at least a part of the discharge space; a hydrogen flow channel that is connected to the discharge space; and leads out purified hydrogen from the starting gas source; a hydrogen separation membrane that partitions the discharge space from the hydrogen flow channel defines at least a part of the discharge space by one surface thereof and defines at least a part of the hydrogen flow channel by the other surface thereof; an electrode that is positioned outside the discharge space; and an adsorbent that is filled in the discharge space and adsorbs the starting gas. In the hydrogen purification method according to the present invention, the starting gas is adsorbed by the adsorbent in the discharge space. Hydrogen molecules, which have been desorbed from the adsorbent by discharge, are allowed to penetrate through the hydrogen separation membrane 4 and led out into the hydrogen flow channel.