a kind of na 3 fso 4 Method for preparing flaky single crystal α-alumina for seeding

A kind of flaky single crystal, alumina technology

Inactive Publication Date: 2017-07-04
CHENGDU UNIVERSITY OF TECHNOLOGY
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The raw materials used in this method are expensive and the calcination temperature is high
[0008] The existing preparation method of flaky single crystal α-alumina has high calcination temperature (>1000°C), high energy consumption, long cycle and complex production process

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
  • a kind of na  <sub>3</sub> fso  <sub>4</sub> Method for preparing flaky single crystal α-alumina for seeding
  • a kind of na  <sub>3</sub> fso  <sub>4</sub> Method for preparing flaky single crystal α-alumina for seeding
  • a kind of na  <sub>3</sub> fso  <sub>4</sub> Method for preparing flaky single crystal α-alumina for seeding

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0041] The above-mentioned one is Na 3 FSO 4 A method for preparing flaky single crystal α-alumina as a seed crystal, wherein in step a, Na 3 FSO 4 Seed crystals can be prepared by the following method: Take NaF and Na 2 SO 4 , add water to dissolve, stir and mix, then evaporate, so that Na 3 FSO 4 Crystals are precipitated and separated to obtain Na 3 FSO 4 Crystal; where, according to the molar ratio, NaF:Na 2 SO 4 =1:0.5~2. Wherein the Na mentioned in step a 2 SO 4 for Na 2 SO 4 ·nH 2 O, where n is an integer between 0 and 10, namely Na 2 SO 4 including anhydrous (Na 2 SO 4 ) and other different hydrous compounds (Na 2 SO 4 ·nH 2 O).

[0042] The above-mentioned one is Na 3 FSO 4 The method for preparing flake single crystal α-alumina as a seed crystal, wherein the aluminum-containing raw material in step a is at least one of aluminum hydrate or transition phase alumina.

[0043] Further, the above-mentioned one is Na 3 FSO 4 A method for preparin...

Embodiment 1

[0050] Weigh 4.2g NaF and 7.1g NaF at a molar ratio of 1:0.5 2 SO 4 , add 50g of water, heat and stir to dissolve to obtain a clear solution, then evaporate the excess water to promote Na 3 FSO 4 Crystal precipitation, solid-liquid separation, Na 3 FSO 4 Crystal 9g. Weigh anhydrous sodium sulfate (Na 2 SO 4 ) 10g to form a solution, then add monohydrate boehmite (Boehmite, AlOOH) 10g, stir evenly and dry in an oven, then weigh 1.75g ​​seed crystal Na 3 FSO 4 (to generate 20% of the mass of α-alumina), grind and mix evenly, then transfer to a corundum crucible for calcination. After heating up to 900°C at a rate of 3°C / min, keep it warm for 2 hours, cool down to room temperature with the furnace, dissolve the material in the crucible with hot water, wash it several times to remove residual molten salt, and dry to obtain flaky α-alumina.

Embodiment 2

[0052] Weigh 4.2g NaF and 14.2g NaF at a molar ratio of 1:1 2 SO 4 , add 100g of water, heat and stir to dissolve to obtain a clear solution, and then evaporate the excess water to promote Na 3 FSO 4 Crystal precipitation, solid-liquid separation, Na 3 FSO 4 Crystals 18.2 g. X-ray diffraction pattern (see attached figure 1 ) confirmed that the prepared product was compatible with Na 3 FSO 4 The standard card (00-015-0678) matches well for Na 3 FSO 4 ; optical micrographs (see attached figure 2 ) can be seen that the prepared Na 3 FSO 4 The crystal morphology is a complete hexagonal plate with uniform size.

[0053] Weigh sodium chloride (NaCl) 12g, anhydrous sodium sulfate (NaCl) 2 SO 4 ) 42g, after mixing evenly, add 18g aluminum hydroxide (Al(OH) 3 ) Grinding and mixing, adding 2.19g seed crystal Na 3 FSO 4 (to generate 18% of the mass of α-alumina), after grinding and mixing evenly, put it into a corundum crucible for calcination. After heating up to 750°...

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 method for preparing platy-monocrystal alpha-aluminum oxide with Na3FSO4 as seed crystals and belongs to the field of preparation of inorganic nonmetal power materials. The method comprises the following steps that firstly, fused salt and Na3FSO4 crystals are added into raw materials containing aluminum and mixed evenly, and a mixed material is obtained; secondly, the mixed material is roasted at 650-1000 DEG C, the roasted mixed material is cooled to the room temperature and then dissolved with hot water at 50-100 DEG C, washing, filtering and drying are carried out, and platy-monocrystal alpha-aluminum oxide is obtained. According to the method, Na3FSO4 seed crystals for preparation are of an obvious hexagonal platy structure, and greatly assist in forming platy aluminum oxide; the roasting temperature is low, and reduction of energy consumption is promoted.

Description

technical field [0001] The invention relates to a preparation method of flaky single crystal α-alumina, in particular to a 3 FSO 4 Method for preparing platelet single crystal alpha-alumina for seeding. Background technique [0002] Flaky single crystal α-alumina is a special type of alumina, which has a flat hexagonal shape and a large diameter-to-thickness ratio, and is a single crystal. Flaky single crystal α-alumina has many excellent properties: (1) high melting point, high hardness, oxidation resistance, corrosion resistance, wear resistance, high resistivity, high thermal conductivity, etc.; (2) high degree of crystallization, unique Hexagonal plate shape, smooth surface and uniform particle size distribution, no agglomeration or less agglomeration. The ratio of diameter to thickness is large, the thickness can reach nanometer level, and the diameter is micron level, which has the dual properties of nanometer and micron powder; (3) good adhesion, strong ability to ...

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): C01F7/44C01D5/00
CPCC01D5/004C01F7/44C01P2002/72C01P2004/02C01P2004/03C01P2004/22C01P2004/61
Inventor 张力唐春梅王明清
Owner CHENGDU UNIVERSITY OF TECHNOLOGY
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