A method of purifying a gas composed of a product gas and one or more impurity gases including combining a feed stream with a second stream thereby forming a combined feed stream, introducing the combined feed stream into a pressure swing adsorption device, thereby producing a high purity product gas stream and an off-gas stream, and introducing the off-gas stream into a membrane separation device, thereby producing a gas stream lean in product gas and a permeate stream.

A system and method for processing unconditioned syngas first removes solids and semi-volatile organic compounds (SVOC), then removes volatile organic compounds (VOC), and then removes at least one sulfur containing compound from the syngas. Additional processing may be performed depending on such factors as the source of syngas being processed, the products, byproducts and intermediate products desired to be formed, captured or recycled and environmental considerations.

A system and method for processing unconditioned syngas first removes solids and semi-volatile organic compounds (SVOC), then removes volatile organic compounds (VOC), and then removes at least one sulfur containing compound from the syngas. Additional processing may be performed depending on such factors as the source of syngas being processed, the products, byproducts and intermediate products desired to be formed, captured or recycled and environmental considerations.

The present invention provides a method (1) and system for the removal of tar from a synthesis gas (10) using a chemical loop (23). A first reactor (20, 55) is fed with mineral particles and the synthesis gas. The mineral particles catalyse the tar in the synthesis gas to produce a mixture comprising hydrogen and a mineral carbonate. A second reactor (15, 70) is fed with oxygen and the mineral carbonate. The oxygen reacts with the mineral carbonate to produce a flue gas (25) comprising carbon dioxide and mineral particles, which are then separated and the mineral particles are recycled to the first reactor.

The invention relates to a process for purifying synthesis gas, comprising at least one stage for separating the crude synthesis gas to be treated into at least two effluents, namely a first part and a complementary part, in which the said first part is subjected to a carbon monoxide conversion stage with steam and the said complementary part is subjected to a COS and HCN catalytic hydrolysis stage, the two gas flows, namely the first part and complementary part, are then each treated separately in two stages intended to remove acid gases such as CO.sub.2 and H.sub.2S, by washing with aqueous solutions of specific amines, before a recombination stage of the two treated effluents.

A system and method for processing unconditioned syngas first removes solids and semi-volatile organic compounds (SVOC), then removes volatile organic compounds (VOC), and then removes at least one sulfur containing compound from the syngas. Additional processing may be performed depending on such factors as the source of syngas being processed, the products, byproducts and intermediate products desired to be formed, captured or recycled and environmental considerations.

Provided is a process for producing synthesis gas with minimized emissions of ammonia. The process includes converting hydrocarbon containing feed stream in reformer tubes (104A-N) and discharging a crude synthesis gas stream and a flue gas stream, routing the flue gas stream through a catalyst unit (112), cooling the crude synthesis gas stream to form an aqueous condensate stream comprising ammonia, tripping the aqueous condensate stream comprising ammonia with a stripping gas stream, routing out a condensate stream depleted in ammonia and a stripping gas stream enriched in ammonia, introducing the stripping gas stream enriched in ammonia into a flue gas duct (110), where both the at least a portion of the flue gas stream and the at least a portion of the stripping gas stream enriched in ammonia pass through a first catalyst zone (114) and subsequently through a second catalyst zone (116) of the catalyst unit (112).

A system and method for processing unconditioned syngas first removes solids and semi-volatile organic compounds (SVOC), then removes volatile organic compounds (VOC), and then removes at least one sulfur containing compound from the syngas. Additional processing may be performed depending on such factors as the source of syngas being processed, the products, byproducts and intermediate products desired to be formed, captured or recycled and environmental considerations.

Provided is a facilitated CO.sub.2 transport membrane having an improved CO.sub.2 permeance and an improved CO.sub.2/H.sub.2 selectivity. The facilitated CO.sub.2 transport membrane includes a separation-functional membrane that includes a hydrophilic polymer gel membrane containing a CO.sub.2 carrier and a CO.sub.2 hydration catalyst. Further preferably, the CO.sub.2 hydration catalyst at least has catalytic activity at a temperature of 100? C. or higher, has a melting point of 200? C. or higher, or is soluble in water.

Process and system for producing an ammonia synthesis gas, the process comprises the steps of: (a) providing a separate stream comprising nitrogen by pressure swing absorption of ambient air; (b) providing a separate stream comprising hydrogen by electrolysis of water and/or steam; (c) combining the separate streams obtained in steps a) and b) into a mixed stream comprising hydrogen and nitrogen; (d) pressurizing the mixed stream from step (c); and (e) removing residual amounts of oxygen further contained in the mixed stream by catalytic hydrogenation of the oxygen with a part of the hydrogen contained in the mixed stream upstream step (d) and/or downstream step (d) and/or during step (d) to produce the ammonia synthesis gas.