CALCINATION
with the best equipment for the best quality and reliable production
DEVELOPMENT
of diverse calcined alumina and alumina-based products
QUALITY CONTROL
during production steps and for final product; composition, article size, density, etc.
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Calcined Alumina (α-Alumina)

to achieve high corrosion resistance

ALPHA offers calcined alumina (α-Alumina) products suitable for a wide range of applications. Calcined alumina is a type of aluminum oxide that has been heated to over 1200°C to remove almost all of the chemically incorporated water and transform to the alpha phase. These products are classified according to their calcination degree, soda content and grinding mechanism. Considering calcination degree, they are classified as Hard Calcined and Medium Calcined. Higher calcination degrees of alumina leads to more crystal growth and higher alpha phase content. The soda content of calcined alumina is precisely controlled in order to achieve higher refractoriness and improved high-temperature mechanical properties. The soda content is classified as Normal Soda, Medium Soda, Low Soda and Ultra Low Soda. Depending on final usage, calcined alumina is used unground or ground. Grinding may be done in batch milling process or continuous milling processes including ball milling and jet milling. In a batch mill, milling is continued until the complete disintegration of particles into their constituent crystals, leaving no residual agglomerates. In continuous milling, more amounts of agglomerates are left behind. The water absorption of alumina is defined by the amount of residual agglomerates.

Advantages:

Applications:

Chemical Analysis (by XRF, %)

Hard Calcined:

Unground
Unit
AH200 (Normal Soda)
AH210 (Medium Soda)
AH220 (Low Soda)
Physical Properties
BET
m2/g
1-2
1-2
1-2
D50
µm
75
75
75
Screen Residue >45 µm
%
Chemical Properties
Alpha Alumina Content
%
≈95
≈95
≈95
Al2O3
%
99.6
99.7
99.7
Na2O
ppm
3500
2500
15003
CaO
ppm
150
150
150
SiO2
ppm
100
550
850
Fe2O3
ppm
115
115
115
MSDS
pdf
TDS
pdf
Ground
Unit
AH202-45 (Normal Soda)
AH212-45(Medium Soda)
AH222-45 (Low Soda)
Physical Properties
BET
m2/g
1-2
1-2
1-2
D50
µm
6
6
6
Screen Residue >45 µm
%
<2
<2
<2
Chemical Properties
Alpha Alumina Content
%
≈95
≈95
≈95
Al2O3
%
99.6
99.7
99.7
Na2O
ppm
3500
2500
15003
CaO
ppm
150
150
150
SiO2
ppm
100
550
850
Fe2O3
ppm
115
115
115
MSDS
pdf
TDS
pdf

Medium Calcined:

Unground Normal Soda
Unit
AM100
AM300
AM700
Physical Properties
BET
m2/g
2-3
3-5
9-15
D50
µm
80
80
80
Screen Residue >45 µm
%
Chemical Properties
Alpha Alumina Content
%
≈93
≈90
≈75
Al2O3
%
99.6
99.6
99.6
Na2O
ppm
3500
3500
3500
CaO
ppm
150
150
150
SiO2
ppm
100
100
100
Fe2O3
ppm
115
115
115
MSDS
pdf
TDS
pdf
Unground Low Soda
Unit
AM120
AM320
Physical Properties
BET
m2/g
2-3
3-5
D50
µm
80
80
Screen Residue >45 µm
%
Chemical Properties
Alpha Alumina Content
%
≈93
≈90
Al2O3
%
99.7
99.7
Na2O
ppm
15003
15003
CaO
ppm
150
150
SiO2
ppm
850
850
Fe2O3
ppm
115
115
MSDS
pdf
TDS
pdf
Ground Low Soda
Unit
AM702-45
Physical Properties
BET
m2/g
9-15
D50
µm
6
Screen Residue >45 µm
%
<2
Chemical Properties
Alpha Alumina Content
%
≈75
Al2O3
%
99.6
Na2O
ppm
3500
CaO
ppm
150
SiO2
ppm
100
Fe2O3
ppm
115
MSDS
pdf
TDS
pdf

Low Calcined:

Unground Normal Soda
Unit
AL100
AL500
Physical Properties
BET
m2/g
15-20
35-40
D50
µm
85
85
Screen Residue >45 µm
%
Chemical Properties
Alpha Alumina Content
%
<70
<70
Al2O3
%
99.6
99.6
Na2O
ppm
3500
3500
CaO
ppm
150
150
SiO2
ppm
100
100
Fe2O3
ppm
115
115
MSDS
pdf
TDS
pdf
Ground Normal Soda
Unit
GA102-45
Physical Properties
BET
m2/g
60-70
D50
µm
6
Screen Residue >45 µm
%
<2
Chemical Properties
Alpha Alumina Content
%
≈25
Al2O3
%
99.5
Na2O
ppm
4300
CaO
ppm
150
SiO2
ppm
100
Fe2O3
ppm
115
MSDS
pdf