Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Method for removing sodium in preparation of high-purity alumina

A high-purity alumina and preparation process technology is applied in the field of high-purity material preparation, and achieves the effects of obvious sodium removal effect, simple use process and no pollution in use process

Active Publication Date: 2013-07-17
KUNMING METALLURGY INST
View PDF4 Cites 21 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, in the existing literature, the single pickling method can only remove sodium at a level of about 0.2%, and the high-purity alumina produced can only reach a purity of 99.99%.

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 in preparation of high-purity alumina
  • Method for removing sodium in preparation of high-purity alumina

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0027] Take 1# aluminum hydroxide powder with an initial sodium content of 137ppm and grind it to ≤500μm for later use; wash the finely ground aluminum hydroxide powder with 45g / L hydrochloric acid in a constant temperature water bath at 50-55°C for 2-3 times to obtain pure Aluminum hydroxide; wash the purified aluminum hydroxide to pH7.0~7.5, dry and dehydrate at 300°C; add 10g / L ammonium chloride to the washed and dried aluminum hydroxide at 30~50 Stir and wash in a constant temperature water bath at ℃ for 2 to 3 times for secondary purification; wash the aluminum hydroxide after secondary purification with pure water at 30 to 50 ℃, dry and dehydrate at 300 ℃ after washing, and transform it into a fluffy ultra-low sodium Aluminum hydroxide, the sodium content is 9ppm after testing.

Embodiment 2

[0029] Take 2# aluminum hydroxide powder with an initial sodium content of 296ppm and grind it to ≤500μm for later use; wash the finely ground aluminum hydroxide powder with 35g / L hydrochloric acid in a constant temperature water bath at 50-55°C for 2-3 times to obtain pure Aluminum hydroxide; wash the purified aluminum hydroxide to pH 7.0-7.5, dry and dehydrate at 350°C; add 15g / L ammonium carbonate to the washed and dried aluminum hydroxide at 30-50°C Stir and wash in a constant temperature water bath for 2 to 3 times for secondary purification; wash the aluminum hydroxide after secondary purification with pure water at 30 to 50°C, dry and dehydrate at 500°C after washing, and transform it into a fluffy ultra-low sodium hydroxide Aluminum, tested sodium content is 8ppm.

Embodiment 3

[0031] Take 3# aluminum hydroxide powder with an initial sodium content of 327ppm and grind it to ≤500μm for later use; wash the finely ground aluminum hydroxide powder with 35g / L hydrochloric acid in a constant temperature water bath at 50-55°C for 2-3 times to obtain pure Aluminum hydroxide; wash the purified aluminum hydroxide to pH 7.0-7.5, dry and dehydrate at 500°C; add 15g / L ammonium carbonate to the washed and dried aluminum hydroxide at 30-50°C Stir and wash in a constant temperature water bath for 2 to 3 times for secondary purification; wash the aluminum hydroxide after secondary purification with pure water at 30 to 50°C, dry and dehydrate at 500°C after washing, and transform it into a fluffy ultra-low sodium hydroxide Aluminum, tested sodium content is 7ppm.

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 method for removing sodium in a preparation of high-purity alumina. The method comprises the steps of purifying, secondary purifying, washing, drying, secondary washing and drying again. The method specifically comprises the following steps of: grinding aluminium hydroxide with high sodium content to be less than or equal to 500mu m, stirring and washing for 2-3 times in thermostatic water bath with temperature being 50-55 DEG C by utilizing a sodium removing agent I to obtain pure aluminium hydroxide; washing the purified pure aluminium hydroxide with water till pH value is 7.0-7.5, drying and dehydrating; adding a sodium removing agent II to the washed and dried aluminium hydroxide, and stirring and washing for 2-3 times in the thermostatic water bath with temperature being 30-50 DEG C; and washing the aluminium hydroxide which is purified for the second time by utilizing pure water with temperature being 30-50 DEG C, drying, dehydrating and transforming the washed aluminium hydroxide to fluffy ultralow sodium aluminium hydroxide. The method has the advantages of convenience, conciseness, no pollution and good sodium-removing effect.

Description

technical field [0001] The invention belongs to the technical field of high-purity substance preparation, and in particular relates to a method for removing sodium during the preparation of high-purity alumina. Background technique [0002] Sodium is considered to be one of the main impurities in the alumina production processes such as the Bayer method, sintering method, and combined method, and is one of the important indicators for the assessment of high-purity alumina grades. The sodium content in alumina mainly depends on the sodium in aluminum hydroxide. There are three main forms of sodium in aluminum hydroxide: ①adsorbed sodium, that is, sodium adsorbed on the surface of aluminum hydroxide and sodium wrapped in crystals, ②intergranular sodium, that is, during the decomposition and crystallization of aluminates, sodium replaces hydroxide The hydrogen atoms in aluminum are intercalated in the intercrystal and ③Crystalline sodium is Na formed during the decomposition 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
IPC IPC(8): C01F7/46
Inventor 谢刚和晓才李怀仁余强魏可李永刚徐庆鑫刁微之闫森陈家辉崔涛陈加希杨大锦包崇军于站良
Owner KUNMING METALLURGY INST
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com