Nanostructured polyelectrolyte bilayers deposited by Layer-by-Layer deposition on nanoporous membranes can be selectively crosslinked to modify the polyelectrolyte charge density and control ionic selectivity independent of ionic conductivity. For example, the polyelectrolyte bilayer can comprise a cationic polymer layer, such as poly(ethyleneimine), and an anionic polymer layer, such as poly(acrylic acid). Increasing the number of bilayers increases the cation selectivity when the poly(ethyleneimine) layer is crosslinked with glutaraldehyde. Crosslinking the membranes also increases the chemical and mechanical strength of the polyelectrolyte films. This controllable and inexpensive method can be used to create ion-selective and mechanically robust membranes on porous supports for a wide range of applications.

The present disclosure provides a method of producing a cation exchange polymer, the method includes polymerizing an anionic monomer in the presence of a polymerizable crosslinker having a cationic functional group. A sufficient amount of anionic monomer is used to provide both the anionic charges necessary for cation exchange, and the anionic charges necessary to pair with the cationic functional groups in the crosslinker.

Method of desalination and wastewater treatment in a microbial desalination cell reactor is provided, the microbial desalination cell reactor has three compartments, an anodic compartment, a cathodic compartment and a saline compartment, the method is carried out by (a) adding electrically conductive particles or electrically conductive material in the anodic compartment and cathodic compartment, (b) adding bacteria species of the genus Geobacter in the anodic compartment and several solutions in the compartments (c) replacing the solutions in the cathodic compartment and in the saline compartment and (d) oxidizing organic matter present in wastewater by bacteria from the genus Geobacter in the anodic compartment and desalinating the solution in the saline compartment and (e)after 20 to 30 operation cycles, replacing the solution in the saline compartment by a solution of hypochlorite salt

Provided are water treatment systems and methods of treating water that include separating dissolved salts from a feed stream using an organic solvent brine stream. For example, described are water treatment systems comprising: an electrodialysis device comprising an inlet feed stream, an inlet brine stream, an outlet product stream, and an outlet brine stream; and a precipitation tank comprising an inlet stream and an outlet stream, wherein the inlet stream of the precipitation tank comprises the outlet brine stream of the electrodialysis device, and the inlet brine stream of the electrodialysis device comprises the outlet stream of the precipitation tank, and wherein inlet brine stream and outlet brine stream comprises an organic solvent.

The present disclosure relates to methods and systems for algae cultivation including the integration of electrochemical carbonate production for enhancing algae growth. More particularly, the present disclosure relates to methods and systems for producing a sodium hydroxide from brine using an electrochemical cell, contacting the sodium hydroxide stream with a CO.sub.2 gas sweep and producing a carbonate stream, and cultivating an algae slurry in a cultivation vessel comprising at least a portion of the carbonate stream.

A waste water treatment system including an electrolysis treatment system and three membrane concentration systems. The electrolysis treatment system includes a first chamber that receives waste water and produces treated waste water, a second chamber that receives first recycled water and produces dilute acid discharge, and a third chamber that receives second recycled water and produces dilute caustic discharge. An anion exchange membrane separates the first chamber from the second chamber. A cation exchange membrane separates the first chamber from the third chamber. The membrane concentration system receives the treated waste water and produces a concentrated aqueous sodium sulfate product and a pure water product. A first thermal concentration system receives the dilute acid discharge and produces first recycled water and a concentrated acid product. The second thermal concentration system receives the dilute caustic discharge and produces second recycled water and a concentrated aqueous sodium sulfate product.

This disclosure provides systems and methods for direct production of lithium hydroxide by utilizing cation selective, monovalent selective, or preferably lithium selective membranes. Lithium selective membranes possess high lithium selectivity over multivalent and other monovalent ions and thus prevent magnesium precipitation during electrodialysis (ED) and also address the presence of sodium in most naturally occurring brine or mineral based lithium production processes.

The present invention provides for nutrient extraction and recovery devices that use the Donnan Membrane Principle (DMP) to cause spontaneous separation of dissolved ions along electrochemical potential gradients, wherein anions and cations such as H.sub.2PO.sub.4.sup.+, HPO.sub.4.sup.2?, PO.sub.4.sup.3?, Mg.sup.2+, Ca.sup.2+, NH.sub.4.sup.+, and K.sup.+ are moved from manure containing waste streams through cation and anion exchange membranes into a recovery stream thereby precipitating target compounds including but not limited to struvite, potassium struvite and hydroxyapatite.

Electrodeionization apparatuses, systems including a reactor system and an electrodeionization system, and methods of purifying acetic acid are provided herein. In some embodiments, the electrodeionization apparatus includes an anode, and three spaced apart membranes located between the anode and the cathode: a first cation exchange membrane, a first anion exchange membrane, a second cation exchange membrane, defining: a first electrode rinse passage between the anode and the first cation exchange membrane, a first concentrate passage between the first cation exchange membrane and the first anion exchange membrane, a feed stream passage located between the first anion exchange membrane and the second cation exchange membrane, and a second electrode rinse passage between the second cation exchange membrane and the cathode. In some embodiments, the electrodeionization apparatus also includes at least one propionate-selective ion exchange resin wafer within the feed stream passage.

An electrode material for extracting an elemental ion from a liquid medium includes at least one electrode material having at least one ion sieve that is capable of retaining or releasing an elemental ion, or a mixture of such ion sieves, wherein the ion sieve or ion sieves is or are coated with carbon.