Adsorbent for rare earth element and method for recovering rare earth element

Patent metadata

Field	Value
Publication number	US-10023937-B2
Application number	US-201514862866-A
Country	US
Kind code	B2
Filing date	Sep 23, 2015
Priority date	Mar 25, 2013
Publication date	Jul 17, 2018
Grant date	Jul 17, 2018

Abstract

An adsorbent for rare earth element and a method for recovering a rare earth element, in which a rare earth element contained in an aqueous solution can be simply and inexpensively adsorbed and recovered, and a rare earth element present in an aqueous solution in combination with a base metal can be selectively adsorbed and recovered. The adsorbent includes a base material and diglycolamic acid introduced into the base material. The method for recovering a rare earth element includes steps of: bringing an aqueous solution containing a rare earth element into contact with the adsorbent for rare earth element to allow the rare earth element to be adsorbed on the adsorbent for rare earth element; and desorbing the rare earth element adsorbed on the adsorbent for rare earth element with an acid of 1 N or less.

First claim

The invention claimed is:

1. An adsorbent for rare earth element which is brought into contact with an aqueous solution containing a rare earth element to adsorb and recover the rare earth element, the adsorbent comprising:
a base material; and
diglycolamic acid introduced into the base material,
wherein the base material is polyethylene or polypropylene.

2. The adsorbent for rare earth element according to claim 1 , wherein the diglycolamic acid has been introduced into the base material by reacting diglycolic acid or diglycolic anhydride with a carrier having a primary amine and/or a secondary amine on the base material.

3. The adsorbent for rare earth element according to claim 2 , wherein the carrier is selected from the group consisting of poly(allylamine), polyethyleneimine, and chitosan.

4. A method for recovering a rare earth element comprising:
bringing an aqueous solution containing a rare earth element into contact with an adsorbent for rare earth element to adsorb the rare earth element on the adsorbent, the adsorbent comprising a base material and diglycolamic acid introduced into the base material; and
desorbing the rare earth element with an acid of 1 N or less.

5. The method for recovering a rare earth element according to claim 4 , wherein the acid is hydrochloric acid.

6. The method for recovering a rare earth element according to claim 5 , wherein the aqueous solution containing a rare earth element is a mixed aqueous solution containing a rare earth element and a base metal in which pH is not adjusted, and the rare earth element is selectively adsorbed and recovered from the mixed aqueous solution.

Assignees

• Aist

Inventors

• Ogata Takeshi
• Tanaka Mikiya

Classifications

• C02F1/286

  using natural organic sorbents or derivatives thereof · CPC title

• C08K3/36

  Silica · CPC title

• B01J20/261

  obtained by reactions only involving carbon to carbon unsaturated bonds (macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds per se C08F) · CPC title

• B01J20/3425

  of sorbents or filter aids comprising organic materials · CPC title

• C08G73/0206

  Polyalkylene(poly)amines · CPC title