A continuous desulfurization process and process system are described for removal of reduced sulfur species at gas stream concentrations in a range of from about 5 to about 5000 ppmv, using fixed beds containing regenerable sorbents, and for regeneration of such regenerable sorbents. The desulfurization removes the reduced sulfur species of hydrogen sulfide, carbonyl sulfide, carbon disulfide, and/or thiols and disulfides with four or less carbon atoms, to ppbv concentrations. In specific disclosed implementations, regenerable metal oxide-based sorbents are integrated along with a functional and effective process to control the regeneration reaction and process while maintaining a stable dynamic sulfur capacity. A membrane-based process and system is described for producing regeneration and purge gas for the desulfurization.

A continuous desulfurization process and process system are described for removal of reduced sulfur species at gas stream concentrations in a range of from about 5 to about 5000 ppmv, using fixed beds containing regenerable sorbents, and for regeneration of such regenerable sorbents. The desulfurization removes the reduced sulfur species of hydrogen sulfide, carbonyl sulfide, carbon disulfide, and/or thiols and disulfides with four or less carbon atoms, to ppbv concentrations. In specific disclosed implementations, regenerable metal oxide-based sorbents are integrated along with a functional and effective process to control the regeneration reaction and process while maintaining a stable dynamic sulfur capacity . A membrane-based process and system is described for producing regeneration and purge gas for the desulfurization.

A continuous desulfurization process and process system are described for removal of reduced sulfur species at gas stream concentrations in a range of from about 5 to about 5000 ppmv, using fixed beds containing regenerable sorbents, and for regeneration of such regenerable sorbents. The desulfurization removes the reduced sulfur species of hydrogen sulfide, carbonyl sulfide, carbon disulfide, and/or thiols and disulfides with four or less carbon atoms, to ppbv concentrations. In specific disclosed implementations, regenerable metal oxide-based sorbents are integrated along with a functional and effective process to control the regeneration reaction and process while maintaining a stable dynamic sulfur capacity . A membrane-based process and system is described for producing regeneration and purge gas for the desulfurization.

In a process for separating a mixture containing carbon monoxide, hydrogen and carbon dioxide, the mixture cooled in a heat exchanger is contacted by a stream of liquid methanol at a temperature below 40 C. to produce carbon dioxide enriched methanol and a carbon dioxide depleted gas relative to the cooled mixture, the carbon dioxide depleted gas is cooled in the heat exchanger and is sent to a separation unit to produce a carbon monoxide enriched stream and a hydrogen enriched stream and the streams enriched in carbon monoxide and hydrogen are heated in the heat exchanger by exchanging heat with the mixture.

Plant and process for separation of sulfur-containing components, H.sub.2S, COS and mercaptans from methanol which is used as absorbent within the Rectisol process by hot regeneration of the methanol laden in the absorption and an additional step for separation of the mercaptans from the methanol by stripping.

The present invention relates to a process for the purification of raw syngas comprising the steps of (a) contacting the raw syngas with water to remove soot, resulting in a soot-rich waste water and a soot-lean syngas; (b) cooling the soot-lean syngas resulting from step (a) to a temperature in the range of from (20) to (50) C.; and (c) contacting the cooled soot-lean syngas resulting from step (b) with water to remove HCN and NH3 resulting in clean syngas and HCN/NH3-rich waste water, wherein: (i) in step (a) the raw syngas is cooled below its dew point by its contact with water; (ii) the HCN/NH3-rich waste water resulting from step (c) is passed through at least one stripping column resulting in a clean water stream and a waste stream; and (iii) at least 50% (v/v) part of the clean water stream is recycled to step (c).

The invention relates to a process for regenerating a laden scrubbing medium from a gas scrubbing for purifying raw synthesis gas in which the laden scrubbing medium is at least partially freed of bound gas constituents in a regeneration stage to obtain a regenerated scrubbing medium. According to the invention it is provided that after withdrawal from the regeneration stage the regenerated scrubbing medium is supplied to an intermediate vessel and the regenerated scrubbing medium is withdrawn from the intermediate vessel and supplied to an absorption apparatus for purifying raw synthesis gas. The invention further relates to an apparatus for performing the process according to the invention comprising a regeneration apparatus in which bound gas constituents are removable from a laden scrubbing medium, wherein according to the invention it is provided that the apparatus comprises an intermediate vessel into which a regenerated scrubbing medium producible in the regeneration apparatus is transferable and in which the regenerated scrubbing medium is storable.

Mixed adsorbent/desiccant beds comprising in some embodiments from about 20 vol % (volume percent) to about 90 vol % of one or more adsorbents and from about 10 vol % to about 80 vol % of one or more desiccants, based on the total volume of the adsorbent/desiccant mixture, prevent water reflux during thermal regeneration of adsorption beds in gas processing plants and methods.

In a process for separating a mixture containing carbon monoxide, hydrogen and carbon dioxide, the mixture cooled in a heat exchanger is contacted by a stream of liquid methanol at a temperature below ?40? C. to produce carbon dioxide enriched methanol and a carbon dioxide depleted gas relative to the cooled mixture, the carbon dioxide depleted gas is cooled in the heat exchanger and is sent to a separation unit to produce a carbon monoxide enriched stream and a hydrogen enriched stream and the streams enriched in carbon monoxide and hydrogen are heated in the heat exchanger by exchanging heat with the mixture.

A mixed salt composition adapted for use as a sorbent for carbon dioxide removal from a gaseous stream is provided, the composition being in solid form and including magnesium oxide, an alkali metal carbonate, and an alkali metal nitrate, wherein the composition has a molar excess of magnesium characterized by a Mg:X atomic ratio of at least about 3:1, wherein X is the alkali metal. A process for preparing the mixed salt is also provided, the process including mixing a magnesium salt with a solution comprising alkali metal ions, carbonate ions, and nitrate ions to form a slurry or colloid including a solid mixed salt including magnesium carbonate; separating the solid mixed salt from the slurry or colloid to form a wet cake; drying the wet cake to form a dry cake including the solid mixed salt; and calcining the dry cake to form a mixed salt sorbent.