A method for recovering an acidic gas, includes: a step of bringing a gas to be treated that contains an acidic gas into gas-liquid into contact with an amine absorbing solution, allowing the amine absorbing solution to absorb the acidic gas, thereby removing the acidic gas from the gas to be treated; a step of allowing the amine absorbing solution that has absorbed the acidic gas to release the acidic gas, thereby regenerating the amine absorbing solution, and at the same time, recovering the released acidic gas; and an analysis step of calculating concentrations of iron ions and/or heavy metal ions in the amine absorbing solution.

Disclosed is an ion exchange resin comprising a polymer having strong acid and strong base groups on the same polymer. In some forms the resin comprises a high density of polymers having strong acid and strong base groups on the same polymer. In some forms the strong acid and strong base groups are in close proximity to one another on the polymer. The disclosure further relates to a mixed bead resin for high salt level desalination.

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Disclosed is an ion exchange resin comprising a polymer having strong acid and strong base groups on the same polymer. In some forms the resin comprises a high density of polymers having strong acid and strong base groups on the same polymer. In some forms the strong acid and strong base groups are in close proximity to one another on the polymer. The disclosure further relates to a mixed bead resin for high salt level desalination.

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A method for conditioning of spent ion exchange resins from nuclear facilities comprises the steps of: mixing the spent ion exchange resins with water to form a reaction mixture; setting and controlling the pH of the reaction mixture in a range from 1.0 to 3.5, preferably in a range from 2.0 to 3.0; adding an oxidant to the reaction mixture, with the temperature of the reaction mixture maintained at 90 ° ° C. or less so that the spent ion exchange resin and the oxidant react with each other to form an aqueous reaction solution comprising the organic reaction products of the spent ion exchange resin; and electrochemically oxidizing the organic reaction products, wherein carbon dioxide is produced and a carbon-depleted aqueous reaction solution having a TOC (total organic carbon) value of less than 50 ppm is obtained. Furthermore, an apparatus for the conditioning of spent ion exchange resins from nuclear facilities is described.

A method for conditioning of spent ion exchange resins from nuclear facilities comprises the steps of: mixing the spent ion exchange resins with water to form a reaction mixture; setting and controlling the pH of the reaction mixture in a range from 1.0 to 3.5, preferably in a range from 2.0 to 3.0; adding an oxidant to the reaction mixture, with the temperature of the reaction mixture maintained at 90 ° ° C. or less so that the spent ion exchange resin and the oxidant react with each other to form an aqueous reaction solution comprising the organic reaction products of the spent ion exchange resin; and electrochemically oxidizing the organic reaction products, wherein carbon dioxide is produced and a carbon-depleted aqueous reaction solution having a TOC (total organic carbon) value of less than 50 ppm is obtained. Furthermore, an apparatus for the conditioning of spent ion exchange resins from nuclear facilities is described.

A fluid treatment apparatus comprising a tank containing a bed of at least one fluid treatment medium, a distributor plate separating the bed from an end portion of the tank, and an inert medium comprising amorphous particles having a harmonic mean diameter from 2.5 to 250 mm and a density from 0.57 to 0.998 cm.sup.3/g. The volume of the end portion containing inert medium is from 25 to 95% of the total volume of the end portion.

A fluid treatment apparatus comprising a tank containing a bed of at least one fluid treatment medium, a distributor plate separating the bed from an end portion of the tank, and an inert medium comprising amorphous particles having a harmonic mean diameter from 2.5 to 250 mm and a density from 0.57 to 0.998 cm.sup.3/g. The volume of the end portion containing inert medium is from 25 to 95% of the total volume of the end portion.

A method for producing an ion exchange resin. The method comprises steps of: (a) providing a basic ion exchange resin in the acidic form which comprises amino polyol groups and has a volume % swell from 15 to 30% upon conversion from the basic form to the acidic form, and (b) washing the resin with water or aqueous acid.

A method for producing an ion exchange resin. The method comprises steps of: (a) providing a basic ion exchange resin in the acidic form which comprises amino polyol groups and has a volume % swell from 15 to 30% upon conversion from the basic form to the acidic form, and (b) washing the resin with water or aqueous acid.

In a method for recovering active metals of a lithium secondary battery according to an embodiment, a cathode active material mixture is collected from the cathode of the lithium secondary battery, the cathode active material mixture is reduced by a reducing reaction to prepare a preliminary precursor mixture, an aqueous lithium precursor solution is formed from the preliminary precursor mixture, and an aluminum-containing material is removed from the aqueous lithium precursor solution with an aluminum removing resin.