A temperature-regenerated hydrophobic liquid composition includes an extracting molecule of a non-alkaline cationic species, a solvating molecule of a complimentary anionic species and a fluidizing agent. The extracting molecule of a non-alkaline cationic species is a macrocycle of which the ring is formed from 24-32 carbon atoms and has the following formula (I) or (II): wherein -n is an integer ranging from 5 to 8, -p is 1 or 2, -m is 3 or 4, -q and t, which may be identical or different, are 0, 1 or 2, —R is a tert-butyl, tert-octyl, O-methyl, O-ethyl, O-propyl, O-isopropyl, O-butyl, O-isobutyl, O-pentyl, O-hexyl, O-heptyl, O-octyl, or OCH.sub.2Phenyl group or a hydrogen atom, and—R′ and R″, which may be identical or different, are chosen from methyl, ethyl, propyl, isopropyl, butyl, isobutyl, heptyl and octyl groups or R′ and R″ together form a pyrrolidine, piperidine or morpholine ring.

A temperature-regenerated hydrophobic liquid composition includes an extracting molecule of a non-alkaline cationic species, a solvating molecule of a complimentary anionic species and a fluidizing agent. The extracting molecule of a non-alkaline cationic species is a macrocycle of which the ring is formed from 24-32 carbon atoms and has the following formula (I) or (II): wherein —n is an integer ranging from 5 to 8, —p is 1 or 2, —m is 3 or 4, —q and t, which may be identical or different, are 0, 1 or 2, —R is a tert-butyl, tert-octyl, O-methyl, O-ethyl, O-propyl, O-isopropyl, O-butyl, O-isobutyl, O-pentyl, O-hexyl, O-heptyl, O-octyl, or OCH.sub.2Phenyl group or a hydrogen atom, and —R′ and R″, which may be identical or different, are chosen from methyl, ethyl, propyl, isopropyl, butyl, isobutyl, heptyl and octyl groups or R′ and R″ together form a pyrrolidine, piperidine or morpholine ring.

A method for extracting a rare earth metal from a mixture of one or more rare earth metals, said method comprising contacting an acidic solution of the rare earth metal with a composition which comprises an ionic liquid to form an aqueous phase and a non-aqueous phase into which the rare earth metal has been selectively extracted; recovering the rare earth metal from the non-aqueous phase; and processing the recovered rare earth metal into a rare earth metal oxide.

A method for extracting a rare earth metal from a mixture of one or more rare earth metals, said method comprising countercurrently contacting an acidic solution of the rare earth metal with a composition which comprises an ionic liquid to form an aqueous phase and a non-aqueous phase into which the rare earth metal has been selectively extracted.

A temperature-regenerated hydrophobic liquid composition includes an extracting molecule of a non-alkaline cationic species, a solvating molecule of a complimentary anionic species and a fluidizing agent. The extracting molecule of a non-alkaline cationic species is a macrocycle of which the ring is formed from 24-32 carbon atoms and has the following formula (I) or (II): wherein —n is an integer ranging from 5 to 8, —p is 1 or 2, —m is 3 or 4, —q and t, which may be identical or different, are 0, 1 or 2, —R is a tert-butyl, tert-octyl, O-methyl, O-ethyl, O-propyl, O-isopropyl, O-butyl, O-isobutyl, O-pentyl, O-hexyl, O-heptyl, O-octyl, or OCH.sub.2Phenyl group or a hydrogen atom, and —R′ and R″, which may be identical or different, are chosen from methyl, ethyl, propyl, isopropyl, butyl, isobutyl, heptyl and octyl groups or R′ and R″ together form a pyrrolidine, piperidine or morpholine ring.

A method for extracting a rare earth metal from a mixture of one or more rare earth metals, said method comprising contacting an acidic solution of the rare earth metal with a composition which comprises an ionic liquid to form an aqueous phase and a non-aqueous phase into which the rare earth metal has been selectively extracted; recovering the rare earth metal from the non-aqueous phase; and processing the recovered rare earth metal into a rare earth metal oxide.

Provided is a method for efficiently purifying scandium by separating scandium and impurities from an acidic solution which contains scandium and impurities that include iron. A method for purifying scandium according to the present invention subjects an acidic solution, which contains an element component including at least ion, while containing scandium, to solvent extraction by means of a mixed extractant containing a phosphoric acid-based extractant and a neutral extractant, thereby extracting scandium from the acidic solution. It is preferable that the phosphoric acid-based extractant is contained in the mixed extractant at a mixing molar ratio within the range of from 5% to 50% (inclusive). It is also preferable that the pH of the acidic solution is adjusted to a value within the range of from 0.0 to 2.0 (inclusive) before the solvent extraction.

Methods for separating and recovering Mn, Co, and Ni from leach solutions include selectively recovering and producing high purity products of Mn, Co, and Ni from leach solutions, combining staged precipitation, sulfide precipitation, and solvent extraction to separate contaminants from the leach solution to isolate and recover Mn, Co, and Ni in high yield and purity.

The invention discloses a treatment method of a chlorine-containing zinc oxide secondary material, which comprises the following steps: 1) leaching the chlorine-containing zinc oxide secondary material I through an acid solution; 2) selectively extracting zinc through di-(2-ethylhexyl)phosphoric acid (P204)-kerosene solvent; 3) implementing stripping-electrolysis zinc recovery; 4) repeating steps 1)-4); 5) taking out the raffinate obtained from the Step (4), mixing the residual taken out raffinate with chlorine-containing zinc oxide secondary material II when balance on chlorine ion input and taking out is achieved; carrying out liquid-solid separation; leaching the separated deposit through acid raffinate of the step 1); 6) after separated solution achieves preset conditions, purifying the chlorine-containing aqueous phase; 7) evaporating and concentrating to crystallize out KCl and NaCl products. The invention is environment-friendly and energy-saving, and free from process wastewater emission; production cost is greatly reduced and secondary pollution of the current dechloridation process is eliminated thoroughly.