A process and plant are proposed for separating a feed mixture predominantly or exclusively containing carbon monoxide and hydrogen, in which the feed mixture is subjected to a cryogenic separation process in which a carbon monoxide-rich liquid and at least one residual gas mixture which is depleted in carbon monoxide and enriched in hydrogen, in comparison with the feed mixture, are formed. It is intended that the at least one residual gas mixture is subjected to a membrane separation process in which at least one hydrogen-rich permeate and at least one carbon monoxide-rich retentate are formed, wherein the or at least one of the carbon monoxide-rich retentates is recirculated to the cryogenic separation process.

The present invention relates to a method for obtaining a hydrogen rich gas from a natural gas comprising gas stream. The present invention relates to a system for obtaining a hydrogen rich gas from a gas stream comprising natural gas. The invention can be used in a chemical plant for hydrocarbon synthesis.

Provided are processes for production of hydrogen to be used in various industrial processes, including in processes for production of ammonia and urea. Included are polygeneration processes that result in ultra-low emissions.

A method of recovering a hydrogen-enriched gas at least 70 percent by volume hydrogen includes introducing into the feed device to a rotary furnace defining a tubular interior space, starting materials containing carbon or hydrocarbons. A mass of water being added to the starting material is regulated according to the content of hydrogen in the gas mixture leaving the rotary furnace. The tubular interior space of the rotary furnace is expanded axially to accommodate thermally expanding the starting material and water in the interior space of the rotary furnace.

A method for hydrogen production starting from a hydrocarbon feed, including a step of reacting the hydrocarbon feed with water steam to obtain a gas stream including hydrogen, carbon monoxide, and carbon dioxide (syngas), heat being provided to the step of reacting the hydrocarbon feed with water steam, the heat being obtained by electrically powered sources; and including removing carbon dioxide from the gas stream. The embodiments further relate to a plant for hydrogen production starting from a hydrocarbon feed, including an electrically powered steam reformer and at least one CO.sub.2 capture system, arranged downstream the electrically powered steam reformer.

The present disclosure relates to systems and methods useful for power production. In particular, a power production cycle utilizing CO.sub.2 as a working fluid may be configured for simultaneous hydrogen production. Beneficially, substantially all carbon arising from combustion in power production and hydrogen production is captured in the form of carbon dioxide. Further, produced hydrogen (optionally mixed with nitrogen received from an air separation unit) can be input as fuel in a gas turbine combined cycle unit for additional power production therein without any atmospheric CO.sub.2 discharge.

Provided are processes for production of hydrogen to be used in various industrial processes, including in processes for production of ammonia and urea. Included are polygeneration processes that result in ultra-low emissions.

A plant for producing ethylene having a reactor to effect oxidative coupling of methane, a work-up unit connected to the reactor to separate a first material stream produced by the reactor into a C.sub.1 material stream and an ethylene product stream and a separation unit connected to the work-up unit to separate the C.sub.1 material stream into a hydrogen-rich product stream and a hydrogen-lean residual gas stream. The plant also includes a steam cracker to produce (5) for producing an olefin-containing and hydrogen-containing crude gas stream. The steam cracker is connected to the work-up unit that separates the crude gas stream along with the first material stream into the C.sub.1 material stream and the ethylene product stream. A portion of the residual gas stream is recycled to the reactor. A process for producing ethylene using the plant is also described.

The process can be used in any hydrocarbon process in which it is desirable to recover hydrogen. The process can include catalytically reforming a hydrocarbon feed, a paraffin dehydrogenation to produce light olefins or a synthesis gas generating process. There is an effluent stream having hydrogen and hydrocarbons that is first sent to an adsorption zone to produce a pure hydrogen stream and a tail gas stream. The tail gas stream is then sent across a feed side of a membrane having the feed side and a permeate side. The membrane that is selected is selective for hydrogen over one or more C1-C6 hydrocarbons and light ends including CO, CO2, N2 and O2, and withdrawing from the permeate side a permeate stream enriched in hydrogen compared with a residue stream withdrawn from the feed side. The permeate stream is then recycled to be sent through the adsorption zone.

Methods of separating CO.sub.2 from a hydrogen synthesis product stream to produce a CO.sub.2 depleted hydrogen stream are provided. Aspects of the methods include combining the hydrogen synthesis product stream with a capture liquid and a cation source in a manner sufficient to produce a CO.sub.2 sequestering solid and separate CO.sub.2 from the hydrogen synthesis product stream to produce the CO.sub.2 depleted hydrogen stream. Also provided are systems for practicing the methods.