Unlock instant, AI-driven research and patent intelligence for your innovation.

A method for extracting rare earth elements from waste fluorescent powder

A rare earth element and phosphor technology, applied in the direction of improving process efficiency, can solve the problems of complicated operation procedures, high processing cost, poor extraction effect, etc., to overcome poor extraction effect, improve extraction rate, reduce melting temperature and The effect of viscosity

Active Publication Date: 2019-03-26
ANHUI UNIVERSITY OF TECHNOLOGY
View PDF2 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0013] The purpose of the present invention is to overcome the problem that hydrometallurgy is usually used to extract the rare earth elements in the waste fluorescent powder in the prior art. The extraction effect of cerium and terbium with less content in the powder is poor, and a method for extracting rare earth elements from waste phosphor powder is provided.

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

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0039] A method for extracting rare earth elements from waste fluorescent powder in this embodiment is to mix and react the waste fluorescent powder with molten salt of halides, and then obtain mixed molten salts containing rare earth halides through solid-liquid separation. The halide is a mixture of aluminum chloride and lithium fluoride powder. The method specifically includes the following steps:

[0040] (1) Accurately weigh aluminum chloride and lithium fluoride according to the mass ratio of 2:1, then mix them evenly and add them into a graphite crucible to obtain a mixed halide. Specifically in this embodiment, both aluminum chloride and lithium fluoride powders are anhydrous halides that do not contain crystal water and are analytically pure. Weigh 40.0g of aluminum chloride powder and 20.0g of lithium fluoride powder and mix evenly. Dry it at 100°C before use to avoid deliquescence due to water absorption.

[0041] (2) Sieve the waste fluorescent powder with a 100-...

Embodiment 2

[0049] A method for extracting rare earth elements from waste fluorescent powder in this embodiment is to mix and react the waste fluorescent powder with molten salt of halides, and then obtain mixed molten salts containing rare earth halides through solid-liquid separation. The halide is a mixture of aluminum chloride and lithium fluoride powder. The method specifically includes the following steps:

[0050] (1) Accurately weigh aluminum chloride and lithium fluoride according to a mass ratio of 3:1, then mix them evenly and add them into a graphite crucible to obtain a mixed halide. Specifically in this embodiment, both aluminum chloride and lithium fluoride powder are anhydrous halides that do not contain crystal water and are analytically pure. Weigh 45.0g of aluminum chloride powder and 15.0g of lithium fluoride powder and mix evenly. Dry it at 140°C before use to avoid deliquescence due to water absorption.

[0051] (2) Sieve the waste fluorescent powder with a 100-mesh ...

Embodiment 3

[0057] A method for extracting rare earth elements from waste fluorescent powder in this embodiment is to mix and react the waste fluorescent powder with molten salt of halides, and then obtain mixed molten salts containing rare earth halides through solid-liquid separation. The halide is a mixture of aluminum chloride and lithium fluoride powder. The method specifically includes the following steps:

[0058] (1) Accurately weigh aluminum chloride and lithium fluoride according to the mass ratio of 4:1, then mix them evenly and add them into a graphite crucible to obtain a mixed halide. Specifically in this embodiment, both aluminum chloride and lithium fluoride powders are anhydrous halides that do not contain crystal water and are analytically pure. Weigh 48.0g of aluminum chloride powder and 12.0g of lithium fluoride powder and mix evenly. Dry it at 200°C before use to avoid deliquescence due to water absorption.

[0059] (2) Sieve the waste fluorescent powder with a 100-...

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

PropertyMeasurementUnit
particle diameteraaaaaaaaaa
Login to View More

Abstract

The invention discloses a method for extracting the rare earth element from waste fluorescent powder, and belongs to the technical field of resource recovery. The method includes the specific steps that (1) aluminum chloride and lithium fluoride powder are accurately weighed and evenly mixed to obtain mixed halide; (2) the waste fluorescent powder is screened, large-particle impurities are removed, and fluorescent powder waste with low impurity content is obtained; (3) the mixed halide is heated and melted, then the fluorescent powder waste is added into fuse salt of the halide, and a reaction is made at 600 DEG C to 1100 DEG C for 5 h to 10 h; and (4) an obtained reaction product is subject to clarification and separation after the reaction, solid remnants and fused salt are obtained, the solid remnants are parts not reacted with the halide fused salt, and the fused salt is a mixture of rare-earth halide-aluminum chloride-lithium fluoride. The aluminum chloride in the method can be selectively reacted with rare earth oxide in the waste fluorescent powder, the lithium fluoride can improve the physical property of the fused salt, and the cerium and terbium extraction efficiency can be effectively improved.

Description

technical field [0001] The invention belongs to the technical field of recovery of rare earth resources and clean utilization of secondary resources, and more specifically relates to a method for extracting rare earth elements from waste fluorescent powder. Background technique [0002] Rare earth phosphors have been widely used in tricolor energy-saving lamps, plasma displays, cathode ray tube TVs, and liquid crystal display backlights because of their high luminous brightness and luminous efficiency, good color purity and stability, long service life and harmlessness. and other fields. With the expansion of the application field of rare earth phosphors and the continuous development of the industry, its output continues to increase. At the same time, a large amount of waste phosphors has also emerged as the times require. It is estimated that about 2,000 tons of rare earth phosphor wastes can actually be recycled in my country every year. Phosphor powder waste contains a...

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
Patent Type & Authority Patents(China)
IPC IPC(8): C22B7/00C22B59/00
CPCC22B7/002C22B59/00Y02P10/20
Inventor 华中胜唐泽韬王鹤赵卓樊友奇刘欢
Owner ANHUI UNIVERSITY OF TECHNOLOGY