Processes for the recovery of ruthenium from materials containing ruthenium or ruthenium oxides or from ruthenium-containing noble metal ore concentrates

摘要

Processes for the recovery of ruthenium from materials containing ruthenium or ruthenium oxides or from ruthenium-containing noble metal ore concentrates, with the steps ofA. the introduction of the material into a highly alkaline alkali hydroxide melt in the presence of nitrate as oxidizing agent with the formation of an oxidized melt residue with water-soluble ruthenate (RuO₄)²⁻,B. the dissolution of the oxidized melt residue obtained in water,C. the addition of a reducing agent,D. the precipitation of the metals formed, can also be used for separating off selenium.;Optionally, ruthenium is separated off by distillation, instead of precipitation, following step B, with the steps of5C the treatment of the ruthenate-containing solution with an oxidizing agent,5D distilling off of the RuO₄ obtained,5E taking up of the RuO₄ from step 5D in hydrochloric acid.By way of further subsequent purification steps, processes for the recovery of ruthenium targets are obtained.