Economical process for alpha alumina production

Details Economical process for alpha alumina production Economical process for alpha alumina production

1987-12-23

1989-07-11

Stoll, Robert L.

Chemistry of inorganic compounds

Oxygen or compound thereof

Metal containing

423628, 423135, 423127, 501153, 502415, C01F 702

Patent

active

048470643

ABSTRACT:
A process for making alpha alumina particles wherein a Bayer process caustic aluminate solution is treated with both alumina hydrate seed material and alpha alumina promoter particles to precipitate alumina hydrate particles. The precipitated particles are separated from the solution and then dried and calcined to produced alpha alumina particles. Addition of promoter particles in the precipitation step lowers the calcination temperture necessary to produce alpha alumina and results in smaller sized crystallites in the product.

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