A composite extractant-enhanced polymer resin comprising an extractant and a polymer resin for direct extraction of valuable metals such as rare earth metals, and more specifically, scandium, from an acid-leaching slurry and/or acid-leaching solution in which ferric ions are not required to be reduced into ferrous ions. The extractant may be cationic, non-ionic, or anionic. More specifically, the extractant di(2-ethylhexyl)phosphoric acid may be used. The polymer resin may be non-functional or have functional groups of sulfonic acid, carboxylic acid, iminodiacetic acid, phosphoric acid, or amines. The composite extractant-enhanced polymer resin may be used for extraction of rare earth metals from acid-leaching slurries or solutions.

Provided is an underwater holding-type lithium recovering apparatus 1000 including: an underwater holder 100 installed on an offshore sea bed; a lithium adsorbent 200 held in the underwater holder 100 and adsorbing lithium ions contained in seawater; a moving ship 300 installed with a cleaning tank 320 cleaning the lithium adsorbent 200 transferred from the underwater holder 100 and a desorbing tank 330 desorbing lithium ions adsorbed in the lithium adsorbent 200 transferred from the cleaning tank 320, and moved to a coastline when lithium ions of a reference value or more are filled in the desorbing tank 330; and a transfer pump 400 transferring lithium ions filled in the desorbing tank 330 to a reservoir 500 installed at the coastline.

A system for nitrate removal from water combining: an ion exchange unit comprising at least one column of an ion exchange resin, a brine bioregeneration circuit comprising a sequential batch reactor (SBR), and an ozonation unit, is disclosed. A method for nitrate removal from water is further disclosed.

An ion exchange tank is provided. The ion exchange tank includes a processing chamber and an additive chamber separated by a weir system, the weir system having a flow channel fluidly connecting the processing chamber to the additive chamber, wherein the flow is divided from the additive chamber by a first partition and divided from the processing chamber by a second partition, wherein the additive chamber comprises a solids-absorbing material disposed therein.

An ion exchange tank is provided. The ion exchange tank includes a processing chamber and an additive chamber separated by a weir system, the weir system having a flow channel fluidly connecting the processing chamber to the additive chamber, wherein the flow is divided from the additive chamber by a first partition and divided from the processing chamber by a second partition, wherein the additive chamber comprises a solids-absorbing material disposed therein.

A process for mechanical separation of sorbent particles in a Direct Lithium Extraction (DLE) process using an ultrafiltration membrane and/or nanofiltration membrane. Also disclosed is a system for mechanical separation of sorbent particles in a Direct Lithium Extraction (DLE) process using an ultrafiltration membrane and/or nanofiltration membrane. Also disclosed is an improved DLE process with a pH controlled upload step.

A process for mechanical separation of sorbent particles in a Direct Lithium Extraction (DLE) process using an ultrafiltration membrane and/or nanofiltration membrane. Also disclosed is a system for mechanical separation of sorbent particles in a Direct Lithium Extraction (DLE) process using an ultrafiltration membrane and/or nanofiltration membrane. Also disclosed is an improved DLE process with a pH controlled upload step.