The present invention includes a novel salt-free water softening method that utilizes an exchange medium (such as a gel exchange polymer, a macroporous exchange polymer, or an inorganic cation exchanger) that is pre-loaded with a polyvalent cation that has low solubility in aqueous phase at nearly neutral pH. The method of the invention does not require use of a sodium salt or mineral acid in the regeneration of the exchange medium.

The present invention includes a novel salt-free water softening method that utilizes an exchange medium (such as a gel exchange polymer, a macroporous exchange polymer, or an inorganic cation exchanger) that is pre-loaded with a polyvalent cation that has low solubility in aqueous phase at nearly neutral pH. The method of the invention does not require use of a sodium salt or mineral acid in the regeneration of the exchange medium.

The present invention comprises a method for the generation of .sup.227Th of pharmaceutically tolerable purity comprising i) preparing a generator mixture comprising .sup.227Ac, .sup.227Th and .sup.223Ra; ii) loading said generator mixture onto a strong base anion exchange resin; iii) eluting a mixture of said .sup.223Ra and .sup.227Ac from said strong base anion exchange resin using a first mineral acid in an aqueous solution; iv) eluting .sup.227Th from said strong base anion exchange resin using a second mineral acid in an aqueous solution whereby to generate a first .sup.227Th solution containing contaminant .sup.223Ra and .sup.227Ac; v) loading the first .sup.227Th solution onto a strong acid cation exchange resin; vi) eluting at least a part of the contaminant .sup.223Ra and .sup.227Ac from said strong acid cation exchange resin using a third mineral acid in aqueous solution; and vii) eluting the .sup.227Th from said strong acid cation exchange resin using a first aqueous buffer solution to provide a second .sup.227Th solution. Purified thorium-227 of pharmaceutical purity and a pharmaceutical composition comprising the same are also provided.

The present invention comprises a method for the generation of .sup.227Th of pharmaceutically tolerable purity comprising i) preparing a generator mixture comprising .sup.227Ac, .sup.227Th and .sup.223Ra; ii) loading said generator mixture onto a strong base anion exchange resin; iii) eluting a mixture of said .sup.223Ra and .sup.227Ac from said strong base anion exchange resin using a first mineral acid in an aqueous solution; iv) eluting .sup.227Th from said strong base anion exchange resin using a second mineral acid in an aqueous solution whereby to generate a first .sup.227Th solution containing contaminant .sup.223Ra and .sup.227Ac; v) loading the first .sup.227Th solution onto a strong acid cation exchange resin; vi) eluting at least a part of the contaminant .sup.223Ra and .sup.227Ac from said strong acid cation exchange resin using a third mineral acid in aqueous solution; and vii) eluting the .sup.227Th from said strong acid cation exchange resin using a first aqueous buffer solution to provide a second .sup.227Th solution. Purified thorium-227 of pharmaceutical purity and a pharmaceutical composition comprising the same are also provided.

The present invention comprises a method for the generation of .sup.227Th of pharmaceutically tolerable purity comprising i) preparing a generator mixture comprising .sup.227Ac, .sup.227Th and .sup.223Ra; ii) loading said generator mixture onto a strong base anion exchange resin; iii) eluting a mixture of said .sup.223Ra and .sup.227Ac from said strong base anion exchange resin using a first mineral acid in an aqueous solution; iv) eluting .sup.227Th from said strong base anion exchange resin using a second mineral acid in an aqueous solution whereby to generate a first .sup.227Th solution containing contaminant .sup.223Ra and .sup.227Ac; v) loading the first .sup.227Th solution onto a strong acid cation exchange resin; vi) eluting at least a part of the contaminant .sup.223Ra and .sup.227Ac from said strong acid cation exchange resin using a third mineral acid in aqueous solution; and vii) eluting the .sup.227Th from said strong acid cation exchange resin using a first aqueous buffer solution to provide a second .sup.227Th solution. Purified thorium-227 of pharmaceutical purity and a pharmaceutical composition comprising the same are also provided.

An ion exchange membrane having a structure that an ion exchange resin is filled in spaces of a porous base film, the porous base film has a structure that at least two porous olefin resin layers are laminated with a bonding strength of 100 gf/cm or more to less than 700 gf/cm and a Gurley air permeance of 500 sec/100 ml or less in terms of a 100 μm thick film. In this ion exchange membrane, base film has high air permeability though it has a multi-layer structure that a plurality of porous resin films are bonded together, and therefore a rise in electric resistance caused by the lamination of the base sheets is effectively suppressed.

An ion exchange membrane having a structure that an ion exchange resin is filled in spaces of a porous base film, the porous base film has a structure that at least two porous olefin resin layers are laminated with a bonding strength of 100 gf/cm or more to less than 700 gf/cm and a Gurley air permeance of 500 sec/100 ml or less in terms of a 100 μm thick film. In this ion exchange membrane, base film has high air permeability though it has a multi-layer structure that a plurality of porous resin films are bonded together, and therefore a rise in electric resistance caused by the lamination of the base sheets is effectively suppressed.

To provide an ion exchange membrane for alkali chloride electrolysis which has high membrane strength and low membrane resistance, thereby capable of reducing the electrolysis voltage during alkali chloride electrolysis. In this ion exchange membrane (1) for alkali chloride electrolysis, a reinforcing material 20 formed by weaving reinforcing yarns 22 and sacrificial yarns 24 is disposed in a layer (S) 14, and layer (S) 14 has elution portions 28 formed by elution of at least portions of the sacrificial yarns 24. In a cross section perpendicular to reinforcing yarns of the warp, the average distance (d1) from the center of a reinforcing yarn 22 to the center of the adjacent reinforcing yarn 22, the total area (P) obtained by adding the cross-sectional area of an elution portion 28 and the cross-sectional area of a sacrificial yarn 24 remaining in the elution portion 28, the number (n) of elution portions between adjacent reinforcing yarns 22, and the ion exchange capacity of a layer (Sa) located on the most anode side in the layer (S) 14 during alkali chloride electrolysis, are controlled to be within specific ranges, respectively.

To provide an ion exchange membrane for alkali chloride electrolysis which has high membrane strength and low membrane resistance, thereby capable of reducing the electrolysis voltage during alkali chloride electrolysis. In this ion exchange membrane (1) for alkali chloride electrolysis, a reinforcing material 20 formed by weaving reinforcing yarns 22 and sacrificial yarns 24 is disposed in a layer (S) 14, and layer (S) 14 has elution portions 28 formed by elution of at least portions of the sacrificial yarns 24. In a cross section perpendicular to reinforcing yarns of the warp, the average distance (d1) from the center of a reinforcing yarn 22 to the center of the adjacent reinforcing yarn 22, the total area (P) obtained by adding the cross-sectional area of an elution portion 28 and the cross-sectional area of a sacrificial yarn 24 remaining in the elution portion 28, the number (n) of elution portions between adjacent reinforcing yarns 22, and the ion exchange capacity of a layer (Sa) located on the most anode side in the layer (S) 14 during alkali chloride electrolysis, are controlled to be within specific ranges, respectively.

This invention relates to a process for the recovery of cobalt ions and tungstic acid and/or its derivatives from aqueous solutions, such as in particular the spent catalytic waters deriving from processes for the oxidative cleavage of vegetable oils. In particular this invention relates to a process for the recovery of cobalt ions and tungstic acid and/or its derivatives which provides for the use of cation-exchange resins.