The present subject matter is directed to a system and method for producing carbon and syngas from carbon dioxide (CO.sub.2). The system includes a first reactor (7) for producing solid carbon (15) from a feed including CO.sub.2 and a volatile organic compound such as methane (1), and a second reactor (20) for producing syngas. Reactions in the first reactor (7) are conducted in a limited oxygen atmosphere. The second reactor (20) can use dry reforming, steam reforming, and/or partial oxidation reforming to produce the syngas (22).

A process for producing synthesis gas, the process including the steps of: a) in a reforming reactor, reacting a hydrocarbon feed stream together with an oxidant gas stream, thereby producing a first synthesis gas stream; b) providing a heated CO.sub.2 rich gas stream to an adiabatic post converter including a second catalyst active for catalyzing steam methane reforming, methanation and reverse water gas shift reactions; and c) in the adiabatic reforming post converter, letting at least a part of the first synthesis gas stream and the heated CO.sub.2 rich gas stream undergo steam methane reforming, methanation and reverse water gas shift reactions to thereby provide a product gas stream, the product gas stream being a synthesis gas stream. Also, a system for producing synthesis gas.

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.

A process for producing syngas that uses the syngas product from an oxygen-fired reformer to provide all necessary heating duties, which eliminates the need for a fired heater. Without the flue gas stream leaving a fired heater, all of the carbon dioxide produced by the reforming process is concentrated in the high-pressure syngas stream, allowing essentially complete carbon dioxide capture.

Herein discussed is a hydrogen production system comprising: a catalytic partial oxidation (CPDX) reactor; a steam generator; and an electrochemical (EC) reactor; wherein the CPDX reactor product stream is introduced into the EC reactor and the steam generator provides steam to the EC reactor; and wherein the product stream and the steam do not come in contact with each other in the EC reactor. In an embodiment, the EC reactor generates a first product stream comprising CO and CO.sub.2 and a second product stream comprising H.sub.2 and H.sub.2O, wherein the two product streams do not come in contact with each other.

Devices and methods for reducing the specific energy required to reform or pyrolyze reactants in plasmas operating at high flow rates and high pressures are presented. These systems and methods include 1) introducing electrons and/or easily ionized materials to a plasma reactor, 2) increasing turbulence and swirl velocity of the flows of feed gases to have improved mixing in a plasma reactor, and 3) reducing slippage from a plasma reactor system. Such plasma systems may allow plasma reactors to operate at lower temperatures, higher pressure, with improved plasma ignition, increased throughput and improved energy efficiency. In preferred embodiments, the plasma reactors are used to produce hydrogen and carbon monoxide, hydrogen and carbon, or carbon monoxide through reforming and pyrolysis reactions. Preferred feedstocks include methane, carbon dioxide, and other hydrocarbons.

A system and method for producing hydrogen from hydrocarbon and steam, including a membrane reformer with multiple membrane reactors each having a tubular membrane. The bore of the tubular membrane is the permeate side for the hydrogen. The region external to the tubular membrane is the retentate side for carbon dioxide. A sweep gas flows through the bore to displace hydrogen in a direction countercurrent to flow of hydrocarbon and steam in the region external to the tubular membrane. The method includes discharging hydrogen as permeate with the sweep gas from the bore, and discharging carbon dioxide in the region external to the tubular membrane as retentate from the membrane reactor.

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.

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.

A system and method of producing hydrogen, including converting hydrocarbon to methane via steam and pre-reforming catalyst in a pre-reformer, converting the methane to hydrogen and carbon dioxide by steam reforming via a reforming catalyst in a membrane reformer, diffusing through hydrogen through a tubular membrane in the membrane reformer.