Patent · US Expired

Method for recovering reusable rare earth compounds

US5728355A · kind A · utility

10Cited by
4References
13Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 23, 1996
Grant dateMar 17, 1998
Priority date
Expiry dateSep 23, 2016

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02P10/20
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

A method for recovering reusable rare earth compounds such as rare earth oxides, rare earth fluorides, or rare earth metals from rare earth alloy scrap in an effective and safe manner. The method includes the steps of: (a) pulverizing rare earth alloy scrap at least by hydrogenating the alloy scrap to obtain pulverized alloy scrap, (b) heating the pulverized alloy scrap to obtain an oxide, (c) contacting the oxide with an acid solution to leach rare earth element into the acid solution in the form of ions, and filtering a resulting solution containing rare earth ions to obtain a filtrate, and (d) forming a precipitate containing rare earth element from the filtrate.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.