A process is described for treating water, in particular for obtaining ultrapure water, in which a decationized water stream is passed at least through a first strong base anion exchange bed and a second strong base anion exchange bed, which is arranged downstream, in particular directly downstream, of the first strong base anion exchange bed. Furthermore, a water treatment system and a counter-current ion exchange unit for carrying out such a process are described.

The present invention relates to a method of removing chromate ions from an ion-exchange effluent, the method comprising: (i) providing an ion-exchange effluent comprising chromate ions obtained from the regeneration of an ion-exchange material, (ii) admixing the ion-exchange effluent with a source of alkali metal dithionite to form a first precipitate, and (iii) removing the first precipitate

The present invention provides methods for cleaning or regenerating a chromatography material for reuse. The methods of the invention can be used for cleaning or regenerating ion exchange chromatography columns for reuse in the large-scale manufacture of multiple polypeptide products where the ion exchange chromatography column in used in overload mode.

The present invention provides methods for cleaning or regenerating a chromatography material for reuse. The methods of the invention can be used for cleaning or regenerating ion exchange chromatography columns for reuse in the large-scale manufacture of multiple polypeptide products where the ion exchange chromatography column in used in overload mode.

An organic polymer composition (OPC) comprising guanidinium-containing A units interconnected with B units of the formula *—R*).sub.r, wherein each asterisk (*) in A units denotes a connection point with an asterisk in B units; R is a hydrocarbon linking group containing at least one carbon atom; r is an integer of 1, 2, or 3; and the composition necessarily includes an anionic species X.sup.m− with a magnitude of charge m of at least 1, wherein the sum of negative charge provided by anionic species X.sup.m− counterbalances the total positive charge provided by the A units. Also described herein is a method for removing one or more oxoanions from an aqueous source by (i) contacting the aqueous source with the above described OPC to result in absorption of the oxoanion into the OPC to produce an oxoanion-containing OPC; and (ii) removing the oxoanion-containing OPC from the aqueous source.

Provided is a process for treating water, wherein the water comprises dissolved ions that comprise an undesired cation, wherein the processes comprises (a) providing a collection of specified polymeric beads wherein 90% or more of the beads by volume are uniform beads; (b) then passing the water through a bed of the collection of polymeric beads to exchange the undesired ion for ions (iv), (c) then passing a regeneration solution comprising dissolved ions (v) of the same species as ions (iv) through the bed of the collection of polymeric beads to exchange ions (v) for the undesired ions.

Provided is a process for treating water, wherein the water comprises dissolved ions that comprise an undesired cation, wherein the processes comprises (a) providing a collection of specified polymeric beads wherein 90% or more of the beads by volume are uniform beads; (b) then passing the water through a bed of the collection of polymeric beads to exchange the undesired ion for ions (iv), (c) then passing a regeneration solution comprising dissolved ions (v) of the same species as ions (iv) through the bed of the collection of polymeric beads to exchange ions (v) for the undesired ions.

Provided are a device and a method for purifying an organic amine solution. The device includes an ion exchange bed having an upper feeding port, through which the ion exchange bed is communicated with an inert gas cylinder, a fifth liquid storage tank and a second liquid adding pump; a lower feeding port, through which the ion exchange bed is communicated with a first liquid adding pump; a lower discharging port, through which the ion exchange bed is communicated with a second liquid storage tank, a third liquid storage tank and a fourth liquid storage tank; and an upper discharging port, through which the ion exchange bed is communicated with the fourth liquid storage tank.

The present invention relates to a method for identifying the unit causing a raw water leak in a condenser of a thermal power plant consisting of n units.

The present invention relates to a method for identifying the unit causing a raw water leak in a condenser of a thermal power plant consisting of n units.