Method for recovering rare earth elements from a solid mixture containing a halophosphate and a compound of one or more rare earth elements

A halophosphate, rare earth element technology, applied in the preparation/processing of rare earth metal compounds, rare earth metal compounds, rare earth metal oxides/hydroxides, etc., can solve the problem of high production cost

Inactive Publication Date: 2012-03-28
RHODIA OPERATIONS SAS
View PDF4 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0007] Now, the emitter compounds present in these powders are expensive ma...

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for recovering rare earth elements from a solid mixture containing a halophosphate and a compound of one or more rare earth elements

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0101] This example relates to a method of the invention wherein nitric acid is used in the acid attack operation.

[0102] As a raw material mixture, luminescent body powder having the following composition expressed as oxides of various elements per 100 grams is used as a raw material:

[0103] Table 1

[0104] Eu 2 o 3

[0105] acid attack

[0106] In a stirred reactor, the phosphor powder was dispersed in water to obtain a dispersion heated to a temperature of 70° C. with a concentration of 170 g / l. The nitric acid solution was poured into the dispersion (which was stirred and heated) within 1 hour until the pH of the solution remained below 1. The mixture was then allowed to digest for 1 hour with stirring, keeping it at the same temperature and the same pH.

[0107] A solution of caustic soda having a concentration equal to 4N was then added to the mixture within 1 hour, so that the pH of the mixture rose to 2. The mixture was stirred for 1 hour.

[...

Embodiment 2

[0131] This example relates to the method according to the invention in which hydrochloric acid is used for the first acid attack of the phosphor powder. Subsequent steps of the method were performed in the same manner as in Example 1.

[0132] The table below shows the analysis of the filtered water recovered at the end of the first acid attack (Table 5) and at the end of the second acid attack (Table 6).

[0133] table 5

[0134] Al 2 o 3

[0135] Table 6

[0136] Eu 2 o 3

[0137] The total yield of rare earth elements was 84.1%.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention relates to a method for recovering rare earth elements from a solid mixture containing a halophosphate and at least one compound of one or more rare earth elements, including: (a) acid etching the mixture; (b) adding a base to bring the pH back up to a value of at least 1,5; (c) etching the solid from step (b) with a solution of soda or potash; (d) acid etching the solid from step (c) until a pH of less than 7 is obtained, resulting in a solid phase and a liquid phase including at least one rare earth salt, and separating the solid phase from the liquid phase.

Description

technical field [0001] The present invention relates to a method for recovering rare earth elements from a solid mixture containing a halophosphate and one or more rare earth element compounds. Background of the invention [0002] The market for energy-saving lamps is expanding rapidly. It is known that lighting is actually a major item in energy consumption in industrialized countries, and using these lamps instead of incandescent lamps will likely reduce the level of lighting energy consumption. [0003] Government directives issued by some countries will strengthen this trend in favor of energy-saving lamps. [0004] Furthermore, the development of this type of lamps has made it necessary to manage their recovery and recycling, taking into account not only the presence of mercury in them, but also the metals included in their composition. [0005] Currently, almost all materials (glass, mercury, metal, etc.) resulting from the processing of lamps of this type are recycl...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): C01B25/32C01B25/37C01F17/00H01J9/52C09K11/01C01F17/206
CPCC01F17/0043C01F17/0068C01B25/37C01B25/32C09K11/7792C01F17/0075C09K11/01H01J9/52C01F17/276C01F17/271C01F17/206Y02W30/50Y02W30/82C01F17/10
Inventor J-J·布拉科尼耶A·罗拉
Owner RHODIA OPERATIONS SAS
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap