A three-dimensional photo/electrodialysis unit includes four compartments. A first compartment holds a three-dimensional electrode and a group of one or more electrochemically active redox species. A first electroactive cation selective membrane couples the first compartment to a second compartment that provides a first feedstock. An electroactive anion selective membrane couples the second compartment to a third compartment that provides a second feedstock. And a second electroactive cation selective membrane couples the third compartment to a fourth compartment

The present disclosure is directed ion-exchange systems and devices that include composite ion-exchange membranes having 3D printed spacers on them. These 3D printed spacers can drastically reduce the total intermembrane spacing within the system/device while maintaining a reliable sealing surface around the exterior border of the membrane. By adding the spacers directly to the membrane using additive manufacturing, the amount of material used can be reduced without adversely impacting the manufacturability of the composite membrane as well as allow for complex spacer geometries that can reduce the restrictions to flow resulting in less pressure drop associated with the flow in the active area of the membranes.

A water purification apparatus and method for optimizing efficiency of the water purification apparatus comprising a fluid circuit including a Reverse Osmosis, RO, unit (3), providing a permeate flow, and an electrically controlled deionization unit (4) downstream the RO unit (3) receiving at least part of the permeate flow. The method comprises obtaining (S1) a value indicative of power consumption by the electrically controlled deionization unit and determining (S2) whether the obtained value indicative of the power consumption meets at least one criterion. The method further comprises controlling recirculation of reject water produced by the water purification apparatus, based on a result of the determining (S2), in order to optimize efficiency of the water purification apparatus.

Disclosed are a hybrid system and method of waste heat utilization-based photovoltaic power generation and seawater desalination, wherein a photovoltaic power generation unit includes a linear Fresnel lens, a beam-splitting cooling tube, a solar cell, and a heat collecting tube; a seawater supply unit includes a seawater storage tank and a pre-treatment storage tank; a heat storage and temperature control unit includes a phase-change heat reservoir and heat exchangers; an electrodialysis unit includes poles, an ion-selective membrane, a desalination chamber, a concentration chamber, pole chambers, a concentrated liquid storage tank and a desalinated liquid storage tank; and an electricity storage and control unit includes a battery pack and a circuit controller. Incident sunlight achieves photovoltaic power generation by a light condensation followed by beam splitting mode; nanoparticle doped seawater absorbs long-wavelength light and transmits short-wavelength light.

Disclosed are a hybrid system and method of waste heat utilization-based photovoltaic power generation and seawater desalination, wherein a photovoltaic power generation unit includes a linear Fresnel lens, a beam-splitting cooling tube, a solar cell, and a heat collecting tube; a seawater supply unit includes a seawater storage tank and a pre-treatment storage tank; a heat storage and temperature control unit includes a phase-change heat reservoir and heat exchangers; an electrodialysis unit includes poles, an ion-selective membrane, a desalination chamber, a concentration chamber, pole chambers, a concentrated liquid storage tank and a desalinated liquid storage tank; and an electricity storage and control unit includes a battery pack and a circuit controller. Incident sunlight achieves photovoltaic power generation by a light condensation followed by beam splitting mode; nanoparticle doped seawater absorbs long-wavelength light and transmits short-wavelength light.

The present disclosure is directed ion-exchange systems and devices that include composite ion-exchange membranes having 3D printed spacers on them. These 3D printed spacers can drastically reduce the total intermembrane spacing within the system/device while maintaining a reliable sealing surface around the exterior border of the membrane. By adding the spacers directly to the membrane using additive manufacturing, the amount of material used can be reduced without adversely impacting the manufacturability of the composite membrane as well as allow for complex spacer geometries that can reduce the restrictions to flow resulting in less pressure drop associated with the flow in the active area of the membranes.

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.

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.

A cell for enhancing a lithium (Li) concentration in a stream includes a housing; a dense lithium selective membrane located in the housing and dividing the housing into a first compartment and a second compartment; a cathode electrode located in the first compartment; an anode electrode located in the second compartment; a first piping circuit fluidly connected to the second compartment and configured to supply a feed stream to the second compartment; a second piping circuit fluidly connected to the first compartment and configured to circulate an enrichment stream through the first compartment; and a power source configured to apply a voltage between the cathode electrode and the anode electrode to initiate an oxidative electrochemical reaction on the anode electrode and a reductive electrochemical reaction on the cathode electrode. The dense lithium selective membrane has a thickness less than 400 m.

Methods for improving ion flux and energy efficiency in a membrane stack of an electrodialysis unit wherein the membrane stack is disposed between an anode and a cathode each in an electrolyte of a selected concentration. Methods include increasing the concentration of the electrolyte, adding a strong base to the electrolyte and adding buffering anions to the electrolyte. Methods for cleaning the electrodes of such a unit involving involve applying a pulsed polarity reversal to the electrodes. Also provided are methods for improving unit operation by increasing the basicity of the electrolyte to the anode and increasing the acidity of the electrolyte to the cathode or alternatively or in addition, by applying heat to increase the operating temperature of at least one of the electrolyte and the treated water stream.