Methods for enzyme-enhanced CO.sub.2 capture include contacting a CO.sub.2-containing gas with an aqueous absorption solution at process conditionssuch as high temperature, high pH, and/or using carbonate-based solutionsin the presence of Thermovibrio ammonificans carbonic anhydrase (TACA) or functional derivative thereof for catalyzing the hydration reaction of CO.sub.2 into bicarbonate and hydrogen ions and/or catalyzing the desorption reaction to produce a CO.sub.2 gas. The TACA may be provided to flow with the solution to cycle through a CO.sub.2 capture system that includes an absorber and a stripper.

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.

Disclosed herein are acid gas absorbents that afford high acid gas (CO2) absorption amount per unit volume and high absorption speed and can prevent the absorbent. components from diffusing. The acid gas absorbent contains an amine compound of the form is (1) and a cyclic amine compound of the formula (3) or (3):

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Disclosed herein are acid gas absorbents that afford high acid gas (CO2) absorption amount per unit volume and high absorption speed and can prevent the absorbent components from diffusing. Also disclosed herein is a method and device for removing an acid gas, in which the energy required for separating the acid gas and regenerating the absorbent is reduced, are provided.

The present invention relates to a process and contactor vessel in which gas and liquid contact occurs to facilitate mass transfer therebetween. In one embodiment, the process includes a fluidised bed including mobile inert primary objects and secondary particles that facilitate turbulent mixing and enhanced gas/liquid surface area in the contactor.

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: ##STR00001##
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.

A method for capturing CO.sub.2 comprising dissolving at least one pure amino acid (AA) in water without the use of a catalyst for establishing protonation of an amino group of the amino acid, adding at least one base solution to the amino acid and water solution to deprotonate the protonated amino group of the amino acid and forming an amino acid-XOHH.sub.2O wherein X is sodium or potassium, and subjecting CO.sub.2 to the amino acid-XOHH.sub.2O to form new nanomaterials is provided. A regenerable nanofiber is disclosed comprising a NaHCO.sub.3 nanofiber, a KHCO.sub.3 nanofiber, or an amino acid nanofiber made from subjecting a CO.sub.2 gas to an amino acid aqueous solvent. Preferably, the amino acid aqueous solvent is one or more of a Gly-NaOHH.sub.2O, an Ala-NaOHH.sub.2O, a Phe-NaOHH.sub.2O, a Gly-KOHH.sub.2O, an Ala-KOHH.sub.2O, and a Phe-KOHH.sub.2O.

Disclosed herein is a porous material comprising a biopolymer functionalized with a carbon dioxide capturing moiety; where the biopolymer is in the form of a foam or an aerogel having a bulk density of 500 grams per cubic meter to 2500 grams per cubic meter. Disclosed herein too is a method comprising functionalizing a biopolymer with a carbon dioxide capturing moiety; dissolving the biopolymer in an aqueous solution to form a first solution; reducing the temperature of the first solution to below the freezing point of the aqueous solution; displacing the aqueous solution with a first solvent that has a lower surface tension than a surface tension of the aqueous solution; and drying the first solvent to produce a porous biopolymer having a bulk density of 500 grams per cubic meter to 2500 grams per cubic meter.

A method for separating carbon dioxide from a gas stream, in particular from a flue gas stream, wherein, a gas stream is brought into contact with a washing medium in an absorber of a separation device and the carbon dioxide contained in the gas stream is separated; the charged washing medium is supplied to a desorber of the separation device to release the carbon dioxide; a vapor stream is removed from the desorber and is supplied to a cooling unit to form a condensate; degradation products, in particular nitrosamines, contained in at least a partial stream of the condensate are photolytically decomposed to decomposition products; at least the decomposition products, in particular nitrites and amines, are removed; and at least a partial stream of the condensate is returned to the desorber. A corresponding separation device separates carbon dioxide from a gas stream.

A processing unit for a liquid washing medium contaminated with sulphur oxides and/or nitrogen oxides, has an evaporation stage for concentrating the active components of the washing medium by an evaporator and/or by a heat exchanger, and has a collecting tank connected to the evaporator and/or to the heat exchanger. The collecting tank is configured as a crystallizer for removing sulfur oxides from the washing medium by crystallization of a sulphate, in particular of potassium sulphate. A separating device for carbon dioxide has a corresponding processing unit, and a method for processing a washing medium contaminated with sulphur oxides and/or nitrogen oxides uses a corresponding processing unit.