Metallgesellschaft Aktiengesellschaft

Vereinigte Aluminum-werke Aktiengesellschaft

Ernst Bareuther

Hubert Bings

Werner Stockhausen

Martin Rahn

Hartmut Pietsch

Fritz Kampf

Wolfgang Turke

Jochen Kauper

A fluidized bed reactor is supplied with fuel, oxygen-containing gas, and kaolinite, which contains water of crystallization. At least 80% by weight of the kaolinite have particle sizes in the range from 0.1 to 3 mm. A fluidized bed at temperatures in the range from 850.degree. to 950.degree. C. is formed in the fluidized bed reactor. A meta-kaolin white pigment which contains water of crystallization not in excess of 2% by weight is withdrawn from the fluidized bed reactor.

Process for preparing a meta-kaolin white pigment from kaolinite

Gold and/or silver is leached from comminuted ore with an alkaline cyanide lixiviant at a superatmospheric pressure of at least 25 bar and with high purity oxygen (at least 90% pure) to reduce the residence time at high yield.

Method of extracting gold and silver from an ore

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Butzbach, Germany

Ernst Bareuther