PRODUCTION OF HIGH-QUALITY IRON OXIDE POWDER FOR FERRITE MAGNETIC MATERIAL

摘要

PURPOSE:To obtain the titled iron oxide powder economically, from the zinc- leaching residue produced as a by-product of wet zinc refining, by leaching the residue with an acid in reducing atmosphere, removing Si, Al, As, etc., from the leachate, precipitating iron from the liquid by oxidation, and purifying the precipitate. CONSTITUTION:The zinc-leaching residue produced as a by-product of wet zinc refining process is leached with an acid in a reducing atmosphere, and the leachate is neutralized with CaCO3 or slaked lime to 4-5 pH, and Si, Al, etc., are precipitated and removed together with gypsum. The leachate is added with copper ion and zinc powder to effect the precipitation and removal of arsenic in the form of copper arsenide. The leachate is adjusted to an iron concentration of =35g/l and made to react with oxidizing gas in an autoclave at =200 deg.C to effect the oxidization of ferrous ion. The precipitated iron compound composed mainly of iron oxide is separated, the soluble components are removed with water, end the iron oxide is dried, calcined and pulverized. After removing the soluble components again with water, the residue is dried to obtain the titled iron oxide powder.