The present invention provides a method for removing a divalent metal cation from a macromolecular compound having an anionic functional group and containing the divalent metal cation, including (1) suspending a macromolecular compound having an anionic functional group and containing a divalent metal cation in a solution in which an electrolyte that releases an alkali metal ion is dissolved at a concentration at which the macromolecular compound is salted out, and (2) performing, in the obtained suspension, an ion exchange reaction to exchange the divalent metal cation contained in the macromolecular compound with the alkali metal ion.

The present invention provides a method for removing a divalent metal cation from a macromolecular compound having an anionic functional group and containing the divalent metal cation, including (1) suspending a macromolecular compound having an anionic functional group and containing a divalent metal cation in a solution in which an electrolyte that releases an alkali metal ion is dissolved at a concentration at which the macromolecular compound is salted out, and (2) performing, in the obtained suspension, an ion exchange reaction to exchange the divalent metal cation contained in the macromolecular compound with the alkali metal ion.

Disclosed is a new continuous lithium-sodium separation method. A lithium-sodium separation mother solution, a first leacheate, a desorption solution, a second leacheate and a lithium-sodium separation adsorption tail solution respectively pass through a lithium-sodium separation mother solution feeding pipe (2), a first leacheate feeding pipe (3), a desorption solution feeding pipe (4), a second leacheate feeding pipe (5) and an adsorption tail solution top desorption solution feeding pipe (6) that are located above and below a rotary disc of a multi-way change-over valve system (1), respectively enter corresponding resin columns (7) by means of pore channels and channels in the multi-way change-over valve system (1), and then are discharged from an adsorption tail solution discharging pipe (8), a first leacheate discharging pipe (9), a qualified liquid discharging pipe (10), a second leacheate discharging pipe (11) and an adsorption tail solution top desorption solution discharging pipe (12), so as to complete the whole technological process, wherein the resin columns (7) are connected in series or in parallel by means of the channels located in the multi-way change-over valve system (1). The method is simple and easy to operate, the resin utilization rate is improved by 20% or more, the efficiency is improved by 40% or more, and the production cost can be reduced by 30-50%. The production reliability is improved, and all-year continuous operation can be realized.

Disclosed is a new continuous lithium-sodium separation method. A lithium-sodium separation mother solution, a first leacheate, a desorption solution, a second leacheate and a lithium-sodium separation adsorption tail solution respectively pass through a lithium-sodium separation mother solution feeding pipe (2), a first leacheate feeding pipe (3), a desorption solution feeding pipe (4), a second leacheate feeding pipe (5) and an adsorption tail solution top desorption solution feeding pipe (6) that are located above and below a rotary disc of a multi-way change-over valve system (1), respectively enter corresponding resin columns (7) by means of pore channels and channels in the multi-way change-over valve system (1), and then are discharged from an adsorption tail solution discharging pipe (8), a first leacheate discharging pipe (9), a qualified liquid discharging pipe (10), a second leacheate discharging pipe (11) and an adsorption tail solution top desorption solution discharging pipe (12), so as to complete the whole technological process, wherein the resin columns (7) are connected in series or in parallel by means of the channels located in the multi-way change-over valve system (1). The method is simple and easy to operate, the resin utilization rate is improved by 20% or more, the efficiency is improved by 40% or more, and the production cost can be reduced by 30-50%. The production reliability is improved, and all-year continuous operation can be realized.

In one aspect, separation media are described herein operable for removing one or more water contaminants including NOM and derivatives thereof. Briefly, a separation medium includes a nanoparticle support and an oligomeric stationary phase forming a film on individual nanoparticles of the support, the film having thickness of 1 to 100 nm. In some embodiments, oligomeric chains of the stationary phase are covalently bonded to the individual nanoparticles.

In one aspect, separation media are described herein operable for removing one or more water contaminants including NOM and derivatives thereof. Briefly, a separation medium includes a nanoparticle support and an oligomeric stationary phase forming a film on individual nanoparticles of the support, the film having thickness of 1 to 100 nm. In some embodiments, oligomeric chains of the stationary phase are covalently bonded to the individual nanoparticles.

A stack of ion exchange membranes suitable for water purification comprising a plurality of anion exchange membranes (AEMs) and a plurality of cation exchange membranes (CEMs), wherein the colour properties of the AEMs are visibly different to the colour properties of the CEMs. The invention also provides a process for making membrane stacks in which the likelihood of there being two consecutive membranes of like charge is reduced. Furthermore, it is easy to identify whether there are two consecutive membranes of like charge present in the stacks.

A stack of ion exchange membranes suitable for water purification comprising a plurality of anion exchange membranes (AEMs) and a plurality of cation exchange membranes (CEMs), wherein the colour properties of the AEMs are visibly different to the colour properties of the CEMs. The invention also provides a process for making membrane stacks in which the likelihood of there being two consecutive membranes of like charge is reduced. Furthermore, it is easy to identify whether there are two consecutive membranes of like charge present in the stacks.

A method for purifying a nonaqueous liquid substance includes: filling a cartridge container with a macroporous or porous type ion exchange resin in a water-wet state to obtain an ion exchange resin-filled cartridge filled with the macroporous or porous type ion exchange resin before water content reduction; reducing a water content of the macroporous or porous type ion exchange resin in the cartridge container until a water content (A) of the macroporous or porous type ion exchange resin after water content reduction becomes 90 to 97% of a water content (B) of the macroporous or porous type ion exchange resin in a saturated equilibrium state; an initial blowing step of allowing the nonaqueous liquid substance before being purified to pass inside the cartridge container filled with the macroporous or porous type ion exchange resin after water content reduction and discharging an initial blow effluent from inside the cartridge container; and purification.

A method for purifying a nonaqueous liquid substance includes: filling a cartridge container with a macroporous or porous type ion exchange resin in a water-wet state to obtain an ion exchange resin-filled cartridge filled with the macroporous or porous type ion exchange resin before water content reduction; reducing a water content of the macroporous or porous type ion exchange resin in the cartridge container until a water content (A) of the macroporous or porous type ion exchange resin after water content reduction becomes 90 to 97% of a water content (B) of the macroporous or porous type ion exchange resin in a saturated equilibrium state; an initial blowing step of allowing the nonaqueous liquid substance before being purified to pass inside the cartridge container filled with the macroporous or porous type ion exchange resin after water content reduction and discharging an initial blow effluent from inside the cartridge container; and purification.