Preparation method of alumina powder

A technology of alumina powder and aluminum hydroxide, applied in the preparation of alumina/hydroxide, etc., can solve the problems of affecting the appearance and performance of alumina products, difficult to obtain high-purity products, and generating corrosive gases, etc. Environmentally friendly, low production process requirements and low cost effects

Inactive Publication Date: 2009-11-11
大连光科纳米材料有限公司
View PDF6 Cites 34 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Chinese patent document 93110316.9 relates to a high-purity ultra-fine alumina production process and device. Aluminum oxide powder is produced after thermal decomposition of ammonium aluminum sulfate. Corrosive gases are generated during the calcination process, which has great environmental problems.
[0003] Although the choline method has many advantages, the choline (molecular formula [(CH 3 ) 3 N(CH 2 CH 2 OH)]OH) is relatively difficult to synthesize and prepare, and it is difficult to obtain high-purity products, which limits its application, and the alcoholic hydroxyl groups in choline will interact with the generated aluminum hydroxide, thereby affecting the morphology and performance of alumina products

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
  • Preparation method of alumina powder
  • Preparation method of alumina powder

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0031] 6.5 grams of 99.7% aluminum flakes that weighed are put into the beaker of 500 milliliters, then add the tetrapropyl ammonium hydroxide (molecular formula (CH) of 100 milliliters 0.45mol / L 3 CH 2 CH 2 ) 4 N + Oh - ) aqueous solution, control the heating temperature in a water bath at 75°C, vibrate and stir for 5 hours, pass the reaction solution through a white steel sieve with a pore size of 150 microns, sieve out a small amount of unreacted aluminum chips, filter under reduced pressure and wash with 20 ml of deionized water The aluminum hydroxide filter cake is obtained by washing, and the filtrate is retained for recycling. After drying the filter cake at 120° C. for 2 hours, dry aluminum hydroxide was obtained, and the aluminum hydroxide was further calcined at 1080° C. for 6 hours to obtain 11.6 grams of α-phase alumina powder.

Embodiment 2

[0033] 4.5 grams of 99.9% metal aluminum foil that weighed is put into the beaker of 500 milliliters, then add the tetraethylammonium hydroxide (molecular formula (CH) of 100 milliliters 0.25mol / L 3 CH 2 ) 4 N + Oh -) aqueous solution, control the heating temperature of the water bath at 65°C, vibrate and stir for 8 hours, pass the reaction solution through a white steel sieve with a pore size of 120 microns, sieve out a small amount of unreacted aluminum chips, filter under reduced pressure and wash with 20 ml of deionized water The aluminum hydroxide filter cake is obtained by washing, and the filtrate is retained for recycling. The filter cake was dried under reduced pressure at 70°C and -0.08MPa for 1.5 hours to obtain dry aluminum hydroxide, which was further calcined at 500°C for 6 hours to obtain 8.3 grams of γ-phase alumina powder.

Embodiment 3

[0035] 7.0 grams of 99.99% metallic aluminum powder that weighed is put into the beaker of 500 milliliters, then add the benzyl trimethylammonium hydroxide (molecular formula C of 100 milliliters 1.5mol / L) 6 h 5 CH 2 (CH 3 ) 3 N + Oh - ) aqueous solution, control the heating temperature in a water bath at 70°C, vibrate and stir for 2 hours, pass the reaction solution through a white steel sieve with a pore size of 120 microns, sieve out a small amount of unreacted aluminum chips, filter under reduced pressure and wash with 20 ml of deionized water The aluminum hydroxide filter cake is obtained by washing, and the filtrate is retained for recycling. After the filter cake was dried at 120°C for 2 hours, dry aluminum hydroxide was obtained, and the aluminum hydroxide was further calcined at 600°C for 6 hours to obtain 13.1 g of γ-phase alumina powder.

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 preparation method of alumina powder. The preparation method of the alumina powder comprises the following steps: metal aluminum and a quaternary ammonium base aqueous solution react in a hot bath to prepare an aluminum hydroxide precipitate, the aluminum hydroxide precipitate is filtered, washed, dried, calcined at high temperature and crushed to prepare alpha-phase alumina powder and gamma-phase alumina powder, and the quaternary ammonium base aqueous solution is still used as filtrate capable of being repeatedly used. A quaternary ammonium base is an organic base with a structural formula of R1R2R3R4NOH, wherein R1, R2, R3 and R4 can be same (or different) alkyl groups (or aromatic groups). The invention has the advantages of low technological condition requirements, environmental protection, low cost and good product repetitiveness, is particularly suitable for mass production and can prepare high-pure ultra-fine alumina powder if high-pure aluminum sheets are adopted as an aluminum source, thereby being applied to the fields, such as high-voltage sodium lighting tubes, long-afterglow luminescent materials, tricolor fluorescent powder, advanced grinding materials, artificial lenses, and the like.

Description

technical field [0001] The invention relates to a preparation method of alumina powder, which belongs to the field of preparation of inorganic non-metallic material powder. Specifically, the present invention relates to a method for preparing aluminum hydroxide by reacting metal aluminum with an aqueous solution of quaternary ammonium alkali, and then calcining to obtain alumina powder. Background technique [0002] Alumina is an inorganic non-metallic material with a wide range of uses. It can be used in various ceramics, rare earth luminescent materials, abrasives, fillers, catalyst carriers and other fields. Common alumina is obtained from mining bauxite, but the alumina thus obtained does not meet the quality requirements for many uses. In order to improve the performance of alumina, people have developed other alumina production methods with industrial value, mainly as follows: (1) Improved Bayer process. Such as Chinese patents 200410023998.3 and 200410021968.9, usin...

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): C01F7/42
Inventor 陈杨英孙颖李明刘辉肖志国
Owner 大连光科纳米材料有限公司
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