1. Kev npaj kev lag luam alumina (purity 98-99. 5%)
BAYER Txheej txheem:
Core process: Bauxite (containing Al ₂ O ∝ 40-60%) → Caustic soda leaching (150-250 degree , 3-5 MPa) → Seed decomposition → Calcination (1100-1200 degree ).
Advantages: Low energy consumption (3.5-4.5 GJ/ton), suitable for processing high alumina silica ratio (A/S>7) ores, accounting rau ntau tshaj 90% ntawm lub ntiaj teb ntau lawm.
Sintering hom:
Haum rau cov alumina qes silica silica piv (a \/ s =3-5}), sodium decumination, nrog kev siv hluav taws xob ntau (} gj \/ tuj).
2. Cov Purity Alumina (Purity ntau dua lossis sib npaug rau 99.9%)
Tshuaj Txuj Ci Qauv:
Alcoholic salt hydrolysis method: Using aluminum isopropoxide as raw material, hydrolysis generates Al (OH) 3 precipitate, which is calcined to obtain 5N grade (99.999%) alumina with controllable particle size (50-200 nm), suitable for semiconductor substrates.
Txhuas Ammonium Carbonate Thermal Decomposition Txoj Kev: Los ntawm kev tswj cov pyrolygring kub ntawm (n}}) α ({{}<50 ppm.
Electrolytic exclining hom:
Siv cov alumina ua cov khoom siv raw, huv los ntawm cov tshuaj ntsev (cryolite alumina
3. NANO Alumina (Particle Loj<100 nm)
Sol gel txoj kev: Aluminium ntsev yog hydrolyzed thiab condensed los ua sol, uas yog ces pel, qhuav, nrog nqaim loj faib (CV<10%), suitable for polishing solution and coating materials.
Gas deposition method: AlCl ∝ reacts with O ₂ in the gas phase at high temperatures (1500-2000 ℃) to generate nano-sized α - Al ₂ O ∝ particles with a purity of>99.9% thiab kev ua tau zoo heev.