▎ 摘　　要

NOVELTY - Separation of gaseous carbon dioxide from ambient atmospheric air containing the gaseous carbon dioxide and other gases different from the gaseous carbon dioxide involves performing cyclic adsorption/desorption using a sorbent material for adsorbing the gaseous carbon dioxide using a unit (A). The unit (A) contains an adsorber structure (6) containing the sorbent material. The adsorber structure is capable of sustaining a temperature of at least 60 degrees C for the desorption of at least gaseous carbon dioxide. The unit (A) is openable to flow-through the ambient atmospheric air, and for contacting the sorbent material for the adsorption step. The adsorber structure comprises an array of individual adsorber elements (5). Each adsorber element comprises at least one support layer, and at least one sorbent layer comprising the sorbent material(s). The sorbent material ensures selective adsorption of carbon dioxide over the other major non-condensable gases in air. USE - Separation of gaseous carbon dioxide for direct air capture or for direct recovery of carbon dioxide from ambient atmospheric air (all claimed). ADVANTAGE - The method enables efficient and economic capture of carbon dioxide from ambient atmospheric air or highly dilute sources. The adsorption and desorption of the sorbent is carried out in a simple and cost-effective manner. DETAILED DESCRIPTION - Separation of gaseous carbon dioxide from ambient atmospheric air containing the gaseous carbon dioxide and other gases different from the gaseous carbon dioxide involves performing cyclic adsorption/desorption using a sorbent material for adsorbing the gaseous carbon dioxide using a unit (A). The unit (A) contains an adsorber structure (6) containing the sorbent material. The adsorber structure is capable of sustaining a temperature of at least 60 degrees C for the desorption of at least gaseous carbon dioxide. The unit (A) is openable to flow-through the ambient atmospheric air, and for contacting the sorbent material for the adsorption step. The adsorber structure comprises an array of individual adsorber elements (5). Each adsorber element comprises at least one support layer, and at least one sorbent layer comprising the sorbent material(s). The sorbent material ensures selective adsorption of carbon dioxide over the other major non-condensable gases in air in the presence of moisture or water vapor. The adsorber elements in the array are arranged parallel to each other and spaced apart from each other forming parallel fluid passages (7) for flow-through of ambient atmospheric air and/or steam. The method preferably involves (a) contacting ambient atmospheric air with the sorbent material for adsorbing at least gaseous carbon dioxide on the sorbent material by flowing through the parallel fluid passages under ambient atmospheric pressure and temperature in the adsorption step, (b) isolating the sorbent containing adsorbed carbon dioxide in the unit (A) from the flow-through while maintaining the temperature in the sorbent, (c) injecting a stream of saturated or superheated steam through the fluid passages by flow-through to induce an increase of the temperature of the sorbent to 60-110 degrees C required for desorption of carbon dioxide, and (d) extracting at least the desorbed gaseous carbon dioxide from the unit (A) and separating gaseous carbon dioxide from the steam by condensation in or downstream of the unit (A) while contacting the sorbent material with steam by injecting and/or partially circulating saturated or superheated steam into the unit (A) to flush and purge both steam and carbon dioxide from the unit (A) at a molar ratio of 4:1-40:1. The extraction and/or steam supply is regulated to maintain the temperature and pressure in the sorbent at the end of the step (c). The sorbent material is brought to ambient atmospheric temperature conditions. In the step (a), the flow speed of the ambient atmospheric air through the adsorber structure is 2-9 m/second. In the step (d), the flow speed of the steam through the adsorber structure is at least 0.2 m/second. The steam is used in the steps (c) and (d) for delivering heat energy during the desorption process. An INDEPENDENT CLAIM is included for device for separating gaseous carbon dioxide from a gas mixture in the form of ambient air. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of the adsorber structure. Adsorber element (5) Adsorber structure (6) Fluid passages (7)