A microchannel-membrane device comprises a microchannel extending through at least one electrode, the microchannel having a predetermined depth; an ionic permselective medium, such as a membrane, across the microchannel between the electrodes; and a heater, or array of heaters, embedded below the microchannel on at least one side of the permselective membrane. The heaters can be either prefabricated or dynamically patterned using laser illumination with/without photoconductive coating. The heaters are on the depletion side of the membrane and induce a vortex which limits the growth of the diffusion area. Operation of the heaters allows for controlled positioning of the end of the diffusion area and with it also the position of the preconcentrated molecule plug.

A method for separation and enrichment of lithium includes the following steps: pretreatment: carrying out at least two dilutions and at least two filtrations on salina aged brine to obtain pretreated brine; separation: separating the pretreated brine via a nanofiltration separation system to obtain nanofiltration permeate and nanofiltration concentrate; first concentration: carrying out first concentration on the nanofiltration permeate via a reverse osmosis system to obtain reverse osmosis concentrate and reverse osmosis permeate; second concentration: carrying out second concentration on the reverse osmosis concentrate via an electrodialysis system to obtain electrodialysis concentrate and electrodialysis permeate, and the electrodialysis concentrate is solution enriching lithium ions. The present application couples several different membrane separation technologies and dilutes the salina aged brine for many times, thereby realizing the purposes of improving separation efficiency of magnesium and lithium and improving the enrichment efficiency of lithium.

The invention relates to a dialysis cell for sample preparation for a chemical analysis method, in particular for ion chromatography. The dialysis cell comprises a donor channel and an acceptor channel extending parallel thereto. The donor channel and the acceptor channel are separated from each other by a selectively permeable dialysis membrane. In particular, an analyte that is dissolved in a donor solution in the donor channel can enter through the dialysis membrane into the acceptor solution in the acceptor channel. The acceptor channel has at least in some sections a volume that is smaller than the volume of the donor channel extending parallel thereto. Acceptor and donor channels are formed from half-cells, between which the dialysis membrane is arranged, wherein the donor channel and the acceptor channel are designed in each case as a recess in a contact surface of one of the half-cells with the dialysis membrane.

A low energy water treatment system and method is provided. The system has at least one electrodialysis device that produces partially treated water and a brine byproduct, a softener, and at least one electrodeionization device. The partially treated water stream can be softened by the softener to reduce the likelihood of scale formation and to reduce energy consumption in the electrodeionization device, which produces water having target properties. At least a portion of the energy used by the electrodeionization device can be generated by concentration differences between the brine and seawater streams introduced into compartments thereof. The brine stream can also be used to regenerate the softener.

A liquid desiccant regeneration system comprises an electrodialysis apparatus having first and second reservoirs, wherein concentration of an input solution in the first reservoir increases to a threshold concentration and concentration of the input solution decreases in the second reservoir during an operation mode. A first redox-active electrolyte chamber comprises a first electrode and a first solution of a redox-active electrolyte material and has a reversible redox reaction with the first electrolyte material to drive an ion into the first reservoir. A second redox-active electrolyte chamber comprises a second electrode and a second solution of a redox-active electrolyte material and has a reversible redox reaction with the second electrolyte material to accept an ion from the second reservoir. A first type of membrane is disposed between the first and second reservoirs, and a second type of membrane, different from the first, is disposed between the respective electrode chambers and reservoirs.

A system comprises an electrodialysis apparatus, which includes first and second reservoirs, wherein a salt concentration in the first reservoir reduces below a threshold concentration, and salt concentration in the second reservoir increases during an operation mode. A first electrode comprises a first solution of a first redox-active electrolyte material, and a second electrode comprises a second solution of a second redox-active electrolyte material. In a first reversible redox reaction between the first electrode and first electrolyte material at least one ion is accepted from the first reservoir, and in a second reversible redox reaction between the second electrode and second electrolyte material at least one ion is driven into the second reservoir. A first type of ion exchange membrane is disposed between the first and second reservoirs, and a second type of ion exchange membrane, different from the first type, is disposed between the respective electrodes and reservoirs.

Electrochemical cell array for the treatment of a sample via electro-(end-)osmotic flow, comprising (i) an electrode chamber, comprising a cathodic compartment (CC) and an anodic compartment (AC), (ii) a cathode (C), being arranged in the cathodic compartment (CC), (iii) an anode (A), being arranged in the anodic compartment (AC), (iv) an intermediate cathodic compartment (C1) (v) an intermediate anodic compartment (A1) (iv) a first selective membrane (M1) being arranged between said cathodic compartment (CC) and said first intermediate cathodic compartment (C1) (v) a second selective membrane (M2) being arranged between said anodic compartment (AC) and said first intermediate anodic compartment (A1) (vi) a treatment compartment (T) for the sample being arranged between said intermediate cathodic compartment (C1) and said intermediate anodic compartment (A1), further comprising a first separator membrane (S1) between said treatment compartment (T) and said intermediate cathodic compartment (C1) and a second separator membrane (S2) arranged between said treatment compartment (T) and said intermediate anodic compartment (A1).

A high recovery variable volume reverse osmosis system where the volume of concentrate cycled through the RO system is reduced in response to recovery levels increasing. By reducing the volume of concentrate cycled through the RO system, this reduces the cycle time of highly saturated concentrate passing through the RO system. Reducing the cycle time of concentrate passing through the RO system tends to minimize or reduce membrane scaling.

[Object] To provide a method for isolating and purifying a minute useful substance. [Solution] Disclosed is a method for isolating and purifying a minute useful substance. The method includes filtering a liquid containing a minute useful substance through a hollow fiber membrane. The hollow fiber membrane has an inner diameter of 0.2 mm to 1.4 mm and a molecular weight cut-off of 100000 to 1000000. The filtering includes a first filtration process of press-fitting the liquid containing the minute useful substance from a first opening on one end side of the hollow fiber membrane and filtering the liquid to separate the liquid into a permeate and a first concentrate, and a second filtration process of press-fitting the first concentrate from a second opening on the other end side of the hollow fiber membrane and filtering the first concentrate to separate the first concentrate into a permeate and a second concentrate. A concentrate is produced in which a concentration of the minute useful substance is increased by filtration in which the first filtration process and the second filtration process are alternately performed a plurality of times at a membrane surface velocity of 0.3 m/sec to 2 m/sec.

The invention is in the field of methods for preparing polymer films, and of such polymer films. The method involves phase separation and requires only aqueous solution, eliminating the need for organic solvents. The aqueous phase separation involves contacting a polymer solution comprising a trigger-responsive polymer with an aqueous coagulation solution in which the trigger-responsive polymer is not soluble.