The present invention relates to an adsorbent comprising an alumina support and at least one alkali element, said adsorbent being obtained by introducing at least one alkali element, identical to or different from sodium, onto an alumina support the sodium content of which, expressed as Na.sub.2O equivalent, before the introduction of the alkali element or elements, is comprised between 1000 and 5000 ppm by weight with respect to the total weight of the support. The invention also relates to processes for the preparation of said adsorbent and use thereof in a process for the elimination of acidic molecules such as COS and/or CO.sub.2.

A plant includes delivery piping (50) transporting aeriform effluent from a production station (200) to a first purification apparatus (10) that comprises at least one static type adsorber device (2) within which at least one filter element (3) is arranged to carry out an initial aeriform effluent adsorption operation, and an emission device (6) of a high temperature fluid that performs a regeneration of the filter element (3) and recovers contaminant adsorbed by the filter element (3). A second purification apparatus (20) is placed along the delivery piping (50), downstream of the first purification apparatus (10), and includes a roto-concentrator (30) that performs at least one second aeriform effluent adsorption operation and at least one desorption operation of contaminants accumulated on the roto-concentrator (30). Lastly, a return pipeline (60) connects the roto-concentrator (30) to an inlet portion (14) of the delivery piping (50).

The invention relates to a VOC reduction apparatus (1) comprising first and a second rotor elements (2, 3) configured to separate VOC (9) from air by adsorption and desorption; a first adsorption zone (16) configured to guide a process airflow (8) through the first rotor element (2); a first desorption zone (13) configured to guide a first regenerating airflow (18) through the first rotor element (2); a converter (36) configured to convert the VOC (9) to residual products (37). The second rotor element (3) is configured to receive the first regenerating airflow (18), after passing through the first rotor element (2), at a second adsorption zone (38). A second desorption zone (34) is configured to guide a second regenerating airflow (32) through the second rotor element (3). The converter (36) is configured to receive the second regenerating airflow (32) after the second regenerating airflow (32) has passed the second rotor element (3).

A system for capturing atmospheric carbon dioxide is disclosed, including a track and a plurality of panels moveably coupled to the track, each panel having a sorbent material. The system also includes a harvest house having a sorbent regeneration system and at least one aperture, and a propulsion system coupled to the track and configured to move each panel in a circuit having a collection phase and a release phase. For each panel, the collection phase of the circuit includes the panel moving along the track to expose the sorbent material to an airflow and allow the sorbent material to capture carbon dioxide. For each panel, the release phase of the circuit includes the panel being sufficiently enclosed inside the harvest house that the sorbent regeneration system may operate on the sorbent material to release captured carbon dioxide from the sorbent material and form an enriched gas.

A system and method of pre-purification of a feed gas stream is provided that is particularly suitable for pre-purification of a feed air stream in cryogenic air separation unit. The disclosed pre-purification systems and methods are configured to remove substantially all of the hydrogen, carbon monoxide, water, and carbon dioxide impurities from a feed air stream and is particularly suitable for use in a high purity or ultra-high purity nitrogen plant. The pre-purification systems and methods preferably employ two or more separate layers of hopcalite catalyst with the successive layers of the hopcalite separated by a zeolite adsorbent layer that removes water and carbon dioxide produced in the hopcalite layers.

A system and method for sulfur recovery, including hydrogenating Claus tail gas, quenching the hydrogenated gas, adsorbing water and hydrogen sulfide from the quenched gas, and regenerating adsorbent with carbon dioxide and/or nitrogen and heating the adsorbent in a regeneration temperature ramp to desorb primarily hydrogen sulfide in a first part of the temperature ramp.

An apparatus (10, 110, 210, 310) for the separation and recovery of CO.sub.2, from air, by a cyclic adsorption/desorption process using a loose particulate sorbent for gas adsorption. The apparatus has a plurality of adjacent, parallel, spaced-apart layers (24, 124, 224, 324), each having a stiff frame supporting a flexible, gas-permeable fabric enclosure for the sorbent. The gas inlet (14, 114, 214, 314) and outlet (18, 118, 216, 316) of the apparatus are on its axially opposite sides, and each layer (24, 124, 224, 324) extending axially within the apparatus. The recovered CO.sub.2 can be either supplied to an enclosed space, recycled to an enclosed space, from which the CO.sub.2 had been separated, or vented to the exterior of the latter enclosed space.

Provided herein are atmospheric water harvesting systems that are tailored with an optimal adsorption threshold, based on energy cost and water availability considerations. The systems include a plurality of adsorbent modules, each containing metal organic frameworks of various adsorption thresholds. Such a design enables real time adjustment to achieve optimal harvesting conditions in changing atmospheric conditions, whether for daily or seasonal humidity variations.

Systems and methods for generating water for an end user are provided herein. The systems include a water generating unit that utilizes and/or controls internal heat sources, as well as external heat, electricity, and/or fluid sources, in response to ambient conditions. The systems may be monitored, optimized, and controlled remotely.

An activated carbon device for adsorbing solvent from a flow of air is regenerated by feeding heated inert gas to the activated carbon and by applying a reduced pressure to the heated activated carbon.