Production process of lithium hydroxide

A lithium hydroxide and production process technology, applied in the direction of alkali metal oxides/hydroxides, inorganic chemistry, alkali metal compounds, etc., can solve the problems of low product quality, low production efficiency, high production cost, etc., to improve purity, The effect of improving production efficiency and improving quality

Active Publication Date: 2015-06-24
SHANGHAI KAIXIN ISOLATION TECH CO LTD
View PDF2 Cites 16 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Therefore, existing technology production cost is high,...

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

[0040] Li 2 The O concentration is 55g / L, and the sulfate content is 60g / L. Pump the clear liquid into the nanofiltration membrane separation system at a temperature of 1-50 degrees Celsius, and operate at a pressure of 2.5 MPa. Filter while adding dialysis water. When the amount of dialysis water is doubled to that of the feed solution, it is concentrated to a concentration of sulfuric acid of 90-100g / L. Permeate Li 2 O concentration 17g / L. The sulfate content in the permeate is less than 0.02g / L, and the sulfate removal rate reaches over 99%. The recovery rate of lithium is 78%.

[0041] The permeate is pumped into a plate evaporator to be concentrated to a lithium hydroxide concentration of 6-8%, and then sent to a crystallization tank for concentration and crystallization. Centrifugal filtration to obtain lithium hydroxide monohydrate crystals. The content of sodium sulfate in the lithium hydroxide monohydrate crystal obtained by primary crystallization is ≤150ppm. ...

Embodiment 2

[0044] Li in supernatant 2 The O concentration is 60g / L, and the sulfate content is 45g / L. Pump the clear liquid into the first-stage nanofiltration membrane separation system at a temperature of 2-40 degrees Celsius and operate at a pressure of 3.8 MPa. Filter while adding dialysis water. When the amount of dialysis water is increased to 1 times of the feed liquid, the permeate of the primary nanofiltration membrane separation system is collected, concentrated in a three-effect evaporator, and then enters a crystallization tank to obtain lithium hydroxide monohydrate crystals. The concentrated solution enters the secondary nanofiltration membrane separation system and continues to add water for dialysis. The filtrate of the secondary nanofiltration membrane separation system is collected and used as dialysis water for the primary membrane separation system. The secondary membrane system is concentrated to a sulfate concentration of 8%, and the Li2O concentration in the per...

Embodiment 3

[0047] The clear liquid first enters the ultrafiltration system for pretreatment. The form of filtration through the ultrafiltration unit is cross-flow filtration, the membrane surface flow velocity is 3 m / s, the operating pressure is 0.1 MPa, and the operating temperature is 40°C. The filter membrane of the ultrafiltration unit adopts a plate type, and the filter aperture of the filter membrane of the ultrafiltration unit is 10nm-1000nm. Then carry out separation, concentration, crystallization according to the method of implementation example 1 or implementation example 2 to obtain the product.

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 discloses a production process of lithium hydroxide. According to the production process of lithium hydroxide, the crystallization mother liquor with high-concentration sodium sulfate and lithium hydroxide is used as the raw material, wherein the crystallization mother liquor with high-concentration sodium sulfate and lithium hydroxide is obtained after crystallization precipitation of sodium sulfate decahydrate in the production process of lithium hydroxide by the lithium sulfate method. Lithium hydroxide is prepared by the following steps: step A, introducing the crystallization mother liquor into a membrane separation system, wherein concentrated sodium sulfate solution is the intercept liquid and lithium hydroxide solution is the permeate liquid; step B, cooling (or cooling after further concentration) the sodium sulfate solution obtained in the step A, separating the sodium sulfate solution by centrifugation and drying the centrifuged sodium sulfate solution, so that crystal of sodium sulfate decahydrate is obtained; step C, concentrating the lithium hydroxide solution obtained in the step A by a steamer and further concentrating the concentrated lithium hydroxide solution in a crystallizing tank, then cooling, crystallizing and separating the concentrated lithium hydroxide solution by centrifugation and drying the centrifuged lithium hydroxide solution to obtain crystal of lithium hydroxide monohydrate. According to the production process, sodium sulfate and lithium hydroxide are effectively separated by the membrane separation technology, so that the purity of the lithium hydroxide solution is improved; thus, the quality of the lithium hydroxide product is effectively improved and production efficiency of the lithium hydroxide product is raised while the production cost is reduced.

Description

technical field [0001] The invention relates to chemical production, in particular to a production process for lithium hydroxide. Background technique [0002] Lithium hydroxide is one of the most important lithium compounds. It has a wide range of uses. The use of lithium hydroxide to produce lithium-based grease has become the largest consumption area of ​​lithium hydroxide due to its wide temperature range, good fire resistance, difficult oxidation, resistance to cold and heat changes, long service life, and strong water resistance. In addition, it is also widely used in chemical industry, national defense, and battery fields. [0003] The production process of lithium hydroxide by lithium sulfate method is usually: spodumene is roasted, acidified, pulped, leached and initially concentrated to obtain lithium sulfate solution. Then, the metathesis reaction of lithium sulfate solution and caustic soda is used to form a mixture of sodium sulfate and lithium hydroxide solu...

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): C01D1/38C01D5/16
CPCC01D1/38C01D5/16
Inventor 葛文越张崇能张芸申雅维
Owner SHANGHAI KAIXIN ISOLATION TECH CO LTD
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