A method of obtaining purified hydrogen and purified carbon monoxide from crude synthesis gas. A first crude synthesis gas stream is passed through a first separation zone to separate a hydrogen stream from a stream comprising carbon monoxide and methane. The carbon monoxide and methane are subjected to thermal reforming to produce a second crude synthesis gas, which is passed through a second separation zone to separate carbon monoxide from the second crude synthesis gas stream.

A method of obtaining purified hydrogen and purified carbon monoxide from crude synthesis gas. A first crude synthesis gas stream is passed through a first separation zone to separate a hydrogen stream from a stream comprising carbon monoxide and methane. The carbon monoxide and methane are subjected to thermal reforming to produce a second crude synthesis gas, which is passed through a second separation zone to separate carbon monoxide from the second crude synthesis gas stream.

The invention includes a gas processing system for transforming a hydrocarbon-containing inflow gas into outflow gas products, where the system includes a gas delivery subsystem, a plasma reaction chamber, and a microwave subsystem, with the gas delivery subsystem in fluid communication with the plasma reaction chamber, so that the gas delivery subsystem directs the hydrocarbon-containing inflow gas into the plasma reaction chamber, and the microwave subsystem directs microwave energy into the plasma reaction chamber to energize the hydrocarbon-containing inflow gas, thereby forming a plasma in the plasma reaction chamber, which plasma effects the transformation of a hydrocarbon in the hydrocarbon-containing inflow gas into the outflow gas products, which comprise acetylene and hydrogen. The invention also includes methods for the use of the gas processing system.

The invention includes a gas processing system for transforming a hydrocarbon-containing inflow gas into outflow gas products, where the system includes a gas delivery subsystem, a plasma reaction chamber, and a microwave subsystem, with the gas delivery subsystem in fluid communication with the plasma reaction chamber, so that the gas delivery subsystem directs the hydrocarbon-containing inflow gas into the plasma reaction chamber, and the microwave subsystem directs microwave energy into the plasma reaction chamber to energize the hydrocarbon-containing inflow gas, thereby forming a plasma in the plasma reaction chamber, which plasma effects the transformation of a hydrocarbon in the hydrocarbon-containing inflow gas into the outflow gas products, which comprise acetylene and hydrogen. The invention also includes methods for the use of the gas processing system.

A process for separating two gaseous streams, including purifying a first gaseous stream in a first acid gas removal absorber, purifying in a first temperature swing adsorption unit, and then separating at a cryogenic temperature in a separation unit to produce a stream of fluid enriched in carbon monoxide and a stream of fluid enriched in hydrogen, sending a second gaseous stream containing at least carbon monoxide, hydrogen and at least one acid gas to a shift reaction unit, the shifted second stream is purified in a second acid gas removal absorber to remove carbon dioxide and the purified second stream is sent as a feed stream to a pressure swing adsorption unit to produce a hydrogen enriched stream, and sending at least part of the stream enriched in hydrogen from the separation unit as a feed stream to the pressure swing adsorption unit to produce the hydrogen-enriched stream.

Some variations provide a process for producing mixed alcohols, comprising: purifying a biogas feedstock to generate a renewable natural gas stream comprising methane; introducing the renewable natural gas stream into a methane-to-syngas unit operated at effective conditions to convert the methane to a first syngas stream containing at least H.sub.2, CO, and CO.sub.2; purifying the first syngas stream, including separating the CO.sub.2 from the first syngas stream, and optionally separating some of the H.sub.2 from the first syngas stream, thereby generating a clean syngas stream; introducing the clean syngas stream into a mixed-alcohol reactor operated at effective alcohol synthesis conditions with an alcohol-synthesis catalyst, thereby generating mixed alcohols; and purifying the mixed alcohols to generate a mixed-alcohol product. The mixed-alcohol product may be blended with a hydrocarbon fuel, such as gasoline, to produce a blended fuel. The blended fuel has significantly lower carbon intensity than the base hydrocarbon fuel.

Some variations provide a process for producing mixed alcohols, comprising: purifying a biogas feedstock to generate a renewable natural gas stream comprising methane; introducing the renewable natural gas stream into a methane-to-syngas unit operated at effective conditions to convert the methane to a first syngas stream containing at least H.sub.2, CO, and CO.sub.2; purifying the first syngas stream, including separating the CO.sub.2 from the first syngas stream, and optionally separating some of the H.sub.2 from the first syngas stream, thereby generating a clean syngas stream; introducing the clean syngas stream into a mixed-alcohol reactor operated at effective alcohol synthesis conditions with an alcohol-synthesis catalyst, thereby generating mixed alcohols; and purifying the mixed alcohols to generate a mixed-alcohol product. The mixed-alcohol product may be blended with a hydrocarbon fuel, such as gasoline, to produce a blended fuel. The blended fuel has significantly lower carbon intensity than the base hydrocarbon fuel.

Embodiments of the invention are directed to methods, processes, and systems for safely and reliably purifying hydrogen from a gas mixture containing hydrogen and oxygen.

Embodiments of the invention are directed to methods, processes, and systems for safely and reliably purifying hydrogen from a gas mixture containing hydrogen and oxygen.

A plant and process for producing a hydrogen rich gas are provided, said process comprising the steps of: reforming a hydrocarbon feed in a reforming step thereby obtaining a synthesis gas comprising CH.sub.4, CO, CO.sub.2, H.sub.2 and H.sub.2O; shifting said synthesis gas in a shift configuration including a high temperature shift step; removal of CO.sub.2 upstream hydrogen purification unit, such as a pressure swing adsorption unit (PSA), and recycling off-gas from hydrogen purification unit and mix it with natural gas upstream prereformer feed preheater, prereformer, reformer feed preheater or ATR or shift as feed for the process.