In this disclosure, a process of recycling acid, base and the salt reagents required in the Li recovery process is introduced. A membrane electrolysis cell which incorporates an oxygen depolarized cathode is implemented to generate the required chemicals onsite. The system can utilize a portion of the salar brine or other lithium-containing brine or solid waste to generate hydrochloric or sulfuric acid, sodium hydroxide and carbonate salts. Simultaneous generation of acid and base allows for taking advantage of both chemicals during the conventional Li recovery from brines and mineral rocks. The desalinated water can also be used for the washing steps on the recovery process or returned into the evaporation ponds. The method also can be used for the direct conversion of lithium salts to the high value LiOH product. The method does not produce any solid effluent which makes it easy-to-adopt for use in existing industrial Li recovery plants.

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.

The present disclosure provides devices and methods of using same for cleansing a solution (e.g., a salt or used dialysis 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.

This combined dehydration device continuously supplies primarily dehydrated sludge to a sludge supply part, the combined dehydration device including: a multiple rotary disk-type solid-liquid separation device and an electroosmosis dehydration device. In the multiple rotary disk-type solid-liquid separation device, a plurality of rotary shafts in which a plurality of rotary disks are fitted and mounted are arranged from the upstream side toward the downstream side and pivotally supported; while the rotary disks are rotated, water to be treated including sludge is supplied from over the rotary disks at the upstream side and is subjected to a primary dehydration treatment; and first dehydrated sludge on the rotary disks is fed and discharged from a sludge discharge part located at the most downstream portion of the rotary disks. In the electroosmosis dehydration device, a sludge supply part is provided at the upstream side of an endless filtration fabric spread between rollers.

A method of cleaning used dialysis fluid having urea to produce a cleaned dialysis fluid, the method including passing the used dialysis fluid having urea through a combination electrodialysis and urea oxidation cell, the cell including (i) a first set of electrodes for separation of the used dialysis fluid having urea into an acid stream and a basic stream, wherein the first set of electrodes includes an anode and a cathode; (ii) one or more second set of electrodes positioned to contact the basic stream with an electrocatalytic surface for decomposition of urea via electrooxidation, wherein the one or more second set of electrodes includes an anode and a cathode; and (iii) at least one power source to provide the first and second sets of electrodes with an electrical charge to activate the electrocatalytic surface.

The present invention relates to a method for preparing high-purity vanadium pentoxide from vanadium-bearing shale by all-wet process. The technical solution is: the Gradient continuous leaching system of vanadium-bearing shale is used to wet activate and compound leach vanadium-bearing shale to obtain vanadium-containing acid leachate. The pH adjusting device of the vanadium-containing acid leachate is used to adjust the pH of vanadium-containing acid leaching leachate. The post-treatment solution is subjected to hydroxime countercurrent extraction after oxidation, and the raffinate returns to the water using in the wet activation and electrodialysis after neutralization, and the loaded organic phase is regenerated by countercurrent reduction stripping. The regenerated organic phase directly returns to hydroxime countercurrent extraction. The pH is adjusted for vanadium precipitation with chemical valence conversion, and the mother liquor after vanadium precipitation is incorporated into the vanadium-containing acid leachate, and the vanadium-containing hydroxide is oxidized and roasted to prepare vanadium pentoxide.

The composite anion exchange membrane includes: a surface layer on a single surface or both surfaces of an anion exchange membrane substrate, in which the above-described surface layer contains a copolymer of a monomer A which is a water-soluble polyfunctional monomer and a monomer B which is a cationic monomer, an anion exchange capacity of the above-described surface layer is 0.05 meq/cm.sup.3 to 0.50 meq/cm.sup.3, and an anion exchange capacity of the above-described anion exchange membrane substrate is 1.0 meq/cm.sup.3 to 5.0 meq/cm.sup.3.

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 combination electrodialysis and urea oxidation cell.

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 object of the present invention is to provide an ultrapure water production method and an ultrapure water production system that are capable of suppressing deterioration in a two-stage reverse osmosis membrane device of the ultrapure water production system caused by an oxidant and further suppressing occurrence of biofouling. The ultrapure water production method using an ultrapure water production system including a two-stage reverse osmosis membrane device including a chlorine-resistant reverse osmosis membrane device at a previous-stage and a non-chlorine-resistant reverse osmosis membrane device to perform a treatment at a subsequent-stage, and the method comprises treating a water-to-be-treated having a total of a free chlorine concentration in Cl equivalent and a free bromine concentration in Br equivalent of 0.01 mg/L or more and less than 0.1 mg/L using the chlorine-resistant reverse osmosis membrane device followed by the non-chlorine-resistant reverse osmosis membrane device of the two-stage reverse osmosis membrane device.