The invention provides a process of purifying a fluid useful in a manufacturing process, particularly in the manufacture of silicon wafers, by removing one or more impurities; and apparatus for use in the process.

The present invention relates to a gas scrubbing process and a plant for removing carbon dioxide (CO2) and water (H2O) from synthesis gas, wherein the synthesis gas includes at least hydrogen (H2), carbon dioxide (CO2) and water (H2O), The invention features a dedicated circuit for water removal which comprises a scrubbing apparatus for removal of water by means of the physical absorption medium used in the gas scrubbing process. The absorption medium supplied to the scrubbing apparatus is withdrawn from a thermal separation apparatus for separation of water and absorption medium. The circuit is arranged such that water entrained via synthesis gas to be purified cannot pass into the main absorption medium circuit which is formed inter alia by an absorption apparatus and a regeneration apparatus. The energy cost and the apparatus complexity especially in respect of the thermal separation apparatus is thus reduced.

The invention relates to a method and to a device for performing a process (P) having at least one heat-consuming process step (F). A first fluid (2), which arises in the process and contains acid gases and water vapor, is cooled indirectly against a second fluid (7), an acidic condensate thus being formed. The invention is characterized in that the first fluid (2) is cooled in at least two successive steps (E1, E2), between which heat for use in the heat-consuming process step (V) is indirectly drawn from the second fluid (10).

A device comprising an electrolyser, a compressor, and a membrane separating device, and to a method for changing the operating mode between normal and standby operation of said device, in the normal operation of which an electrolysis raw product comprising carbon dioxide is converted in the electrolyser into an electrolysis product containing carbon dioxide and carbon monoxide, at least one portion of which is conducted via the compressor and is fed at an increased pressure to the membrane separating device in order to obtain a retentate which is enriched in carbon monoxide and depleted of carbon dioxide compared with the electrolysis product. According to the invention, in order to change from the normal operation into the standby operation, the electrolyser is completely isolated from the membrane separating device in terms of flow and then shut down, wherein the pressure ratios in the membrane separating device are largely maintained.

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 invention relates to a process and a plant for removing thiols from synthesis gas. Thiols and optionally thiophene and carbon disulfide are absorbed in a dedicated absorption stage with methanol as physical absorption medium. Methanol laden with at least thiols is freed of thiols in a stripping stage with methanol vapours as stripping gas and the methanol vapours-containing thiols are freed of methanol in a scrubbing stage. The process according to the invention minimizes methanol losses and the amounts of coolant required for the process.

The present invention relates to a process for removing carbon dioxide from a synthesis gas having at least hydrogen and carbon dioxide in which the synthesis gas is at least partially freed of carbon dioxide in an absorption apparatus by physical absorption at elevated absorption pressure. The carbon dioxide is subsequently desorbed by pressure reduction relative to the absorption pressure in a plurality of serially arranged flash stages and an at least partially regenerated absorption medium is withdrawn from the last of the plurality of serially arranged flash stages, recompressed to absorption pressure and recycled into the absorption apparatus for use as absorption medium. It is also provided according to the invention that a partially regenerated absorption medium from a flash stage upstream of the last of the plurality of serially arranged flash stages is recompressed to absorption pressure and recycled into the absorption apparatus for use as absorption medium.

A method for separating a gas mixture flow, n which uses a temperature-change adsorption plant having a number of adsorption units which are operated in a first and a second operating mode. The first operating mode comprises guiding a gas mixture flow at least in part through an adsorption chamber of an adsorption unit and subjecting this flow to an adsorptive exchange with at least one adsorbent. The second operating mode comprises guiding a first heat transfer fluid flow at a first temperature through a heat-exchange arrangement of an adsorption unit. The first operating mode also comprises guiding a second heat transfer fluid flow at a second temperature through the heat-exchange arrangement of the respective adsorption unit. The adsorption units are operated in a third operating mode which comprises guiding a third heat transfer fluid flow at a third temperature through the heat-exchange arrangement of the respective adsorption unit.

Generation of bubbles in an organic-substance production apparatus is suppressed. A gas treatment method including: an adsorption step of passing a source gas containing at least carbon dioxide and nitrogen through an adsorption unit for adsorbing carbon dioxide to reduce a carbon dioxide concentration in the source gas; a supply step of supplying the source gas whose carbon dioxide concentration has been reduced by the adsorption step to an organic-substance production apparatus; and a monitoring step of monitoring a carbon dioxide concentration and a nitrogen concentration in the source gas; wherein the adsorption step has an ability regulation step of enhancing an ability of the adsorption unit to reduce a carbon dioxide concentration in the source gas, when a total concentration of the carbon dioxide concentration and the nitrogen concentration monitored in the monitoring step exceeds a threshold value.

An aminated siliceous adsorbent, which is the reaction product of dried acidified rice husk ash having disordered mesopores and an amino silane, wherein amine functional groups are present on an external surface and within the mesopores of the dried acidified rice husk ash, and wherein the aminated siliceous adsorbent has a carbon content of 24 to 30 wt. %, based on a total weight of the aminated siliceous adsorbent. A method of making the aminated siliceous adsorbent and a method of capturing CO.sub.2 from a gas mixture with the aminated siliceous adsorbent.