In a general aspect, a carbon dioxide removal system is presented. In some cases, a gas-liquid contactor is wetted with an alkaline capture solution. A first flow from a first gaseous feed including CO.sub.2 from a first source is directed to interact with the alkaline capture solution in the gas-liquid contactor, which forms a first CO.sub.2-rich alkaline capture solution. A second flow from a second gaseous feed including CO.sub.2 from a second, distinct source is directed to interact with the first CO.sub.2-rich alkaline capture solution, which forms a second CO.sub.2-rich alkaline capture solution. In some cases, the second flow is independent of the first gaseous feed, and a concentration of CO.sub.2 in the second CO.sub.2-rich alkaline capture solution is higher than a concentration of CO.sub.2 in the first CO.sub.2-rich alkaline capture solution. CO.sub.2 can be separated from the second CO.sub.2-rich alkaline capture solution.

A composition and a device for purification of nitrogen-oxide-containing gas is provided. It can purify harmful nitrogen-oxide-containing gases, such as nitric oxide or nitrogen dioxide. The composition includes an alkaline substance and at least one organic acid, the organic acids having an enediol group, enediamine group, or amine group of cyclopentane compounds, cyclohexane compounds, cycloheptane compounds, or phenanthrene compounds.

A formulation and process for capturing CO.sub.2 use an absorption mixture containing water, biocatalysts and a carbonate compound. The process includes contacting a CO.sub.2-containing gas with the absorption mixture to enable dissolution and transformation of CO.sub.2 into bicarbonate and hydrogen ions, thereby producing a CO.sub.2-depleted gas and an ion-rich solution, followed by subjecting the ion-rich solution to desorption. The biocatalyst improves absorption of the mixture comprising carbonate compounds and the carbonate compound promotes release of the bicarbonate ions from the ion-rich solution during desorption, producing a CO.sub.2 gas stream and an ion-depleted solution.

A process for desorbing CO.sub.2 gas from an ion-rich aqueous mixture comprising bicarbonate and hydrogen ions, includes providing micro-particles in the ion-rich aqueous mixture; and feeding the ion-rich aqueous mixture into a desorption reactor; the micro-particles comprising a support material and biocatalysts supported and stabilized by the support material and being sized and provided in a concentration in the desorption reactor such that the micro-particles are carried with the ion-rich aqueous mixture to promote transformation of the bicarbonate and hydrogen ions into CO.sub.2 gas and water, thereby producing a CO.sub.2 gas stream and an ion-depleted solution.

A method for separating carbon dioxide from a gas flow, in particular from a flue gas flow, where a gas flow is brought in contact with a scrubbing medium in an absorber of a separating device and carbon dioxide contained in the gas flow is separated, the loaded scrubbing medium is fed to a desorber of the separating device in order to release the carbon dioxide, a vapor flow is drawn from the desorber and is fed to a cooling device in order to form condensate, and the condensate formed in the cooling device is at least partially fed to a purifying device, in which degradation products contained in the condensate are removed by reverse osmosis and/or by an ion exchanger. A separating device is adapted for separating carbon dioxide from a gas flow.

An anesthetic circuit is provided for treating a patient. The anesthetic circuit includes a membrane having a plurality of hollow fibers. Also provided is a fluid separation apparatus connectable to an anesthetic circuit. In a further embodiment, a method is provided for anesthetic treatment of a patient.

A method of generating electricity from an amine-based acid gas capture process using an electrolytic cell containing an anode and a cathode and an amine based electrolyte comprising: contacting a metal based redox material with an amine based electrolyte in the presence of an anode to form a metal-ammine complex in solution; adding an absorbed or absorbable acid gas to the metal-ammine complex containing electrolyte to form an acid gas absorbed electrolyte; and contacting the acid gas absorbed electrolyte with a cathode deposit, wherein the acid gas breaks up the metal-ammine complex in the metal-ammine complex containing electrolyte thereby generating a potential difference between the anode and the cathode.

Methods for removing oxyanions from water according to the following steps: (i) dissolving an oxyanion precipitating compound into the aqueous source to result in precipitation of an oxyanion salt of the oxyanion precipitating compound; and (ii) removing the oxyanion salt from the water containing the oxyanion to result in water substantially reduced in concentration of the oxyanion; wherein the oxyanion precipitating compound has the following composition:

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wherein A is a ring-containing moiety and X.sup.m is an anionic species with a magnitude of charge m. The invention employs bis-iminoguanidinium compounds according to Formula (1a) as well as neutral precursor compounds according to Formula (1), which can be used for removing undesirable species from aqueous solutions or air, such as removal of sulfate from water and carbon dioxide from air.

Method for extracting a gas from a gas mixture by: during a purification step, bringing a first sorption medium into contact with the gas mixture in order to extract the gas from the gas mixture, whereby an enriched first sorption medium is formed in which the gas is at least partially sorbed; during a regeneration step, bringing a second sorption medium into contact with the enriched first sorption medium in order to extract the gas from the enriched liquid first sorption medium; whereby for the contact in the purification step and/or in the regeneration step use is made of a separate venturi ejector.

A high-flux direct air capture (DAC) contactor is provided. The contactor includes stainless steel mesh elements interlaced into a structured packing to increase the effective surface area for a suitable solvent. In laboratory testing, the contactor demonstrated significant potential in driving down the cost of solvent absorption-based DAC due to its high specific surface area and CO.sub.2 uptake efficiency, resistance to corrosion, optimal wettability, smaller relative size, and low manufacturing cost. As a potential breakthrough strategy, the highly efficient CO.sub.2 capture contactor can be employed to significantly reduce capital costs in a compact DAC system.