Hoogovens Groep B.v.

Noranda Inc.

Anthonie Van Sandwijk

Gezinus Van Weert

Serge Payant

Carole Allen

Peter Kondos

Job Dijkhuis

The present invention relates to an apparatus and a process for producing zinc oxide from a zinc-bearing material. The process according to the present invention comprises the steps of leaching the complex sulfide material with hydrochloric acid and oxygen; precipitating iron from the leach solution using magnesium oxide and oxygen; removing copper, silver, cadmium, cobalt and lead from the leach solution by cementation with zinc dust; precipitating zinc oxide from the leach solution using magnesium oxide; and spray roasting the remaining magnesium chloride leach solution to regenerate hydrochloric acid and magnesium oxide. The present invention further relates to processes for recovering copper, silver, lead, and iron from complex sulfide materials.

Production of zinc oxide from complex sulfide concentrates using chloride processing

A method for selectively separating Zn from an acidic aqueous solution containing ions of Zn and Fe obtained by leaching of blast furnace dust using hydrochloric acid comprises first precipitating Fe from the solution and then treating the resultent Zn-containing solution with an alkali to precipitate Zn. The Zn-containing solution is treated in two stages; in the first precipitation step the pH is adjusted to from 4.0 to 4.3.

Method for selectively separating a non-ferrous metal

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Leiden, Netherlands

Anthonie Van Sandwijk