Method for removing sodium from coarse lithium by gas agitation under condition of vacuum, distillation at moderate temperature

A gas stirring and vacuum technology is applied in the field of gas stirring crude lithium vacuum medium temperature distillation and sodium removal, which can solve the problems of complex installation, high cost, complex production process, etc., and achieve the effects of simple process, high recovery rate and reasonable process.

Inactive Publication Date: 2004-10-27
KUNMING UNIV OF SCI & TECH
View PDF0 Cites 14 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The high-temperature distillation method needs to evaporate most of the lithium, which consumes a lot of power and the distillation efficiency is low. Due to the high distillation temperature, lithium has a serious corrosion effect on the equipment. In order to improve the distillation efficiency, some equipment is equipped with electromagnetic or mechanical stirring. The mixing method has disadvantages such as complicated installation and high operation and maintenance costs
Another process is to purify lithium chloride, then electrolyze the lithium chloride with higher purity to obtain metal lithium with lower sodium content, and then distill it to obtain pure lithium. The production process of this method is complicated, the cost is high, and the production volume Small

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 removing sodium from coarse lithium by gas agitation under condition of vacuum, distillation at moderate temperature
  • Method for removing sodium from coarse lithium by gas agitation under condition of vacuum, distillation at moderate temperature

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0016] Embodiment 1. The furnace height is 1500mm, the diameter is Φ500mm, and the processing capacity is 20 kg / furnace; the inert gas distribution pipe is a straight pipe with a pipe diameter of Φ5mm, and the filter diameter is Φ50mm, and the thickness is 5mm. The crude lithium raw material has a sodium content of 0.7%, which is directly put into a vacuum furnace for melting, the distillation temperature is 440°C, the vacuum degree is 3Pa, filled with argon gas and stirred and distilled for 3 hours, the sodium content of the refined lithium is less than 0.005%, reaching Requirements for battery-grade lithium; the direct recovery rate is greater than 90%.

Embodiment 2

[0017] Embodiment 2: The furnace height is 1800mm, the diameter is Φ700mm, and the processing capacity is 70 kg / furnace; the inert gas distribution pipe is two rows of straight pipes, the pipe diameter is Φ8mm, the filter diameter is Φ60mm, and the thickness is 8mm. The crude lithium raw material has a sodium content of 1.0%. After melting, it is put into a vacuum furnace. The distillation temperature is 500° C., the vacuum degree is 3 Pa, and it is filled with argon gas to stir and distill for 5 hours. The sodium content of the refined lithium is less than 0.005%, reaching Requirements for battery-grade lithium; the direct recovery rate is greater than 90%.

Embodiment 3

[0018] Embodiment 3: The furnace height is 2000mm, the diameter is Φ1000mm, and the processing capacity is 100 kg / furnace; the inert gas distribution pipe is surrounded by a circle, the pipe diameter is Φ10mm, the filter diameter is Φ70mm, and the thickness is 10mm. The crude lithium raw material has a sodium content of 1.5%. After melting, it enters a vacuum furnace at a temperature of 440°C and a vacuum of 3 Pa. It is filled with argon and stirred and distilled for 8 hours. The sodium content of refined lithium is less than 0.005%, reaching battery grade. Lithium requirements; direct yields are greater than 90%.

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
diameteraaaaaaaaaa
diameteraaaaaaaaaa
diameteraaaaaaaaaa
Login to view more

Abstract

A process for removing sodium from the coarse lithium includes smelting the coarse lithium containing Na (0.1-1.5%) in the pot of vacuum furnace at 200+/-10 deg.C, flowing in vacuum furnace, heating to 400-520 deg.C under 1-5 Pa, flushing inertial gas into molten lithium for stirring for 3-8 hrs while evaporating Na, filtering, and casting ingot.

Description

[0001] 1. Technical Field: Vacuum Metallurgy 2. Background technology: [0002] Lithium metal is generally produced by electrolysis of potassium chloride-lithium chloride molten salt, the purity of the product is 98-99%, and the impurity sodium content is 0.1-1.5%. The metal lithium used in lithium batteries requires the content of sodium to be less than 2×10 -4 , for which electrolytic lithium needs to be refined. At present, the preparation of lithium with a purity greater than 99.9% requires filtration, vacuum distillation, rectification or regional methods. The high-temperature distillation method needs to evaporate most of the lithium, which consumes a lot of power and the distillation efficiency is low. Due to the high distillation temperature, lithium has a serious corrosion effect on the equipment. In order to improve the distillation efficiency, some equipment is equipped with electromagnetic or mechanical stirring. The mixing method has disadvantages such as compli...

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 Applications(China)
IPC IPC(8): C22B26/12
Inventor 杨斌戴永年杨部正魏剑刘永成刘大春旦义明吴昆华陈为亮
Owner KUNMING UNIV OF SCI & TECH
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