METHOD OF REMOVAL OF CHLORINE AND FLUORINE FROM DUST-LIKE ZINC-CONTAINING MATERIALS Russian patent published in 2008 - IPC C22B19/00 C22B7/02 

FIELD: non-ferrous metallurgy; removal of chlorine and fluorine from dust-like zinc-containing materials of lead-zinc processes, for example from Waelz sublimates or slag sublimates.

SUBSTANCE: proposed method includes calcination of materials for obtaining chlorine- and fluorine-containing sublimates followed by leaching-out which is conducted in sulfuric acid solution at separation of solid from solution. Then, solution is cleaned from chlorine step by step by sedimentation with the aid of univalent copper and from fluorine by sedimentation with the aid of lime, thus obtaining fluorine-containing lime cake which is dried to moisture content of 20-30% and is subjected to Waelz process treatment at extraction of zinc into Waelz oxide and conversion of fluorine and calcium into waste clinker.

EFFECT: possibility of utilization and removal of fluorine from zinc production process with waste or copper-containing clinker.

1 dwg, 1 tbl, 1 ex