A pre-processing electrodialysis process for adjusting the proportion of constituents of mixed salt electrolytes for the production of various chemicals, or for facilitating precipitation through passing the feed through an electrodialysis cell operated with a relatively small salinity step increase, resulting in changed proportionality of constituent anions and cations in the dilute product or the concentrate product.

The present disclosure provides devices and methods of using same for cleansing a solution (e.g., a salt solution) of urea via electrooxidation, and more specifically to cleansing a renal therapy solution/dialysis solution of urea via electrooxidation so that the renal therapy solution/dialysis solution can be used or reused for treatment of a patient. In an embodiment, a device for the removal of urea from a fluid having urea to produce a cleansed fluid includes a urea decomposition unit and an electrodialysis unit.

Provided are water treatment systems and methods of treating water that include separating boron and concentrating lithium. For example, described are water treatment systems comprising: a first phase comprising a first plurality of electrodialysis units configured to separate boron from a feed stream, and a second phase comprising a second plurality of electrodialysis units, wherein the feed stream of at least one electrodialysis unit of the second plurality of electrodialysis units comprises an outlet brine stream of at least one electrodialysis unit of the first plurality of electrodialysis units, and wherein the second plurality of electrodialysis units are configured to produce a product brine stream achieving 90-99% lithium recovery.

A hybrid electro-pressure driven method for the recovery, purification, and concentration of lithium salts is described. A fractionating electrodialysis stack equipped with selective ion exchange membranes is used to separate a lithium containing brine into a monovalent enriched fraction and a divalent enriched fraction. The monovalent enriched fraction is further processed to remove remaining impurities by use of pressure driven nanofiltration. An optional concentrating electrodialysis device may further concentrate the monovalent enriched fraction in lithium content. The method may be combined with a subsequent solvent extraction and electrolysis step to produce lithium hydroxide, a Li+ selective sorbent step for producing purified lithium chloride, or a Li+ selective sorbent and precipitative step to produce lithium carbonate.

A bipolar electrodialysis (BPED) cell is able to bipolar convert salt solutions into acid and base solutions. However, protons migrate through the anion exchange membranes and tend to neutralize the base solution. In a bipolar electrodialysis system described herein, multiple BPED cells are arranged to provide a multi-stage treatment system. Up to half, or up to one third, of the stages have cells with acid block anion membranes. The one or more stages with acid block anion membranes are located at the acid product output end of the system, where the acid concentration in the system is the highest. Replacing the traditional anion membranes in some of the stages with acid block anion membranes allows higher concentration products to be produced with moderate increase in energy consumption.

A process for preparing an ion-exchange membrane having a textured surface profile comprising the steps (i) and (ii): (i) screen-printing a radiation-curable composition onto a membrane in a patterned manner; and (ii) irradiating and thereby curing the printed, radiation-curable composition; wherein the radiation-curable composition has a viscosity of at least 30 Pa.Math.s when measured at a shear rate of 0.1 s.sup.1 at 20 C.

A method of recovering purified partly-hydrolyzed cellulose particles from a composition comprising agglomerated partly-hydrolyzed cellulose particles and an acid, using electrodialysis. The invention addresses the problem of reducing the acid to very low levels while avoiding the high capital and operating costs, high water usage and large filtration surface area or dilution time requirements of the prior art processes. Following dilution, concentration by centrifuging or settling, and/or dialysis of the composition, the composition is treated in an electrodialysis cell to remove ions, such as free sulfate from sulfuric acid. The method may include having an anion exchange resin in the feed compartment of the electrodialysis cell, adding a base to the receiving solution in the electrodialysis cell, and a second step of electrodialysis of the purified partly-hydrolyzed cellulose particles.

A device selected from the group consisting of an electrodialysis or reverse electrodialysis unit, an electrodeionization module and a flow through capacitor, the device comprising a membrane obtained from a process comprising the following steps: applying a curable composition to a support; and curing the composition to form a membrane; wherein the curable composition comprises: (i) 2.5 to 50 wt % crosslinker comprising at least two acrylamide groups; (ii) 12 to 65 wt % curable ionic compound comprising an ethylenically unsaturated group and a cationic group; (iii) 10 to 70 wt % solvent; (iv) 0 to 10 wt % of free radical initiator; and (v) non-curable salt comprising a cation and an anion, wherein the anion is not sulfate; wherein the molar ratio of (i):ii) is greater than 0.10 and less than 5.

Described herein is a process for upgrading effluent treatment plants for pulp and paper production processes, where salts are removed from the effluent for water reuse and chemical recovery. The process comprises a first dialysis system for salt removal, a second treatment system for recovery or re-concentration, and optionally a post-treatment of the re-concentrate preventing liquid discharges to the environment. In the first system, a reversible electrodialysis or reversible pulsed step is carried out, separating the salts from the effluent, which are sent to the second treatment system to concentrate the salts (re-concentrate) or transform them into useful chemicals for the same process (recovery). Chemical recovery is achieved by electrodialysis with bipolar membranes or metathesis, to reduce the re-concentrate stream, which cannot be reused in the same plant. Lastly, this stream may be treated by spray drying, crystallization or evaporation.

An electrodialysis desalination device includes a first electrode including a first-stage side; a second electrode including a first-stage side; and a first stage between the first-stage side of the first electrode and the first-stage side of the second electrode. The first stage includes at least one first-stage cell pair positioned between the first-stage side of the first electrode and the first-stage side of the second electrode, and each cell pair includes a pair of first-stage selectively permeable ion-exchange membranes with alternating selectivity that define first-stage channels on opposite sides of each first-stage membrane for respective flows of a first-stage diluate stream and a first-stage concentrate stream. A single pump is configured to pump the diluate streams and the concentrate streams through the first stage.