Method for separating rare earth element

• Main Authors: OGATA, Takeshi, TANAKA, Mikiya, NARITA, Hirokazu, MUROTA, Tadatoshi
• Format: Patent
• Language: English
• Published: 30.04.2020
• Subjects: CHEMISTRY; FERROUS OR NON-FERROUS ALLOYS; METALLURGY; PRETREATMENT OF RAW MATERIALS; PRODUCTION AND REFINING OF METALS; TREATMENT OF ALLOYS OR NON-FERROUS METALS

Provided is a method for easily separating a rare earth element contained in an aqueous solution at low cost. A method for separating a rare earth element, which is characterized by comprising: an adsorption step wherein a solution containing rare earth element ions and tetravalent ions of a metal element other than the rare earth element ions is brought into contact with an adsorbent, thereby having the rare earth element ions and the tetravalent ions adsorbed on the adsorbent; a rare earth element ion removal step wherein the adsorbent after the adsorption step is brought into contact with a first acidic aqueous solution, thereby having the rare earth element ions removed from the adsorbent; and a tetravalent ion removal step wherein the adsorbent after the rare earth element ion removal step is brought into contact with a second acidic aqueous solution, thereby having the tetravalent ions removed from the adsorbent. This method for separating a rare earth element is also characterized in that: the adsorbent is composed of a substrate and diglycolamic acid introduced into the substrate; the first acidic aqueous solution is from 0.1 mol/L to 4 mol/L (inclusive) of hydrochloric acid or nitric acid; and the second acidic aqueous solution is from 0.5 mol/L to 10 mol/L (inclusive) of sulfuric acid.