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

摘要

Recovery (M1) of ruthenium from materials containing ruthenium or ruthenium oxides or from ruthenium-containing noble metal ore concentrates involves introducing the material into an alkali hydroxide melt in the presence of nitrate as oxidizing agent and forming an oxidized melt residue with water-soluble ruthenate; subjecting the oxidized melt residue to dissolution in water; adding a reducing agent; and precipitating the metals formed. Recovery (M1) of ruthenium from materials containing ruthenium or ruthenium oxides or from ruthenium-containing noble metal ore concentrates involves either: introducing the material into an alkali hydroxide melt in the presence of nitrate as oxidizing agent and forming an oxidized melt residue with water-soluble ruthenate; subjecting the oxidized melt residue to dissolution in water; adding a reducing agent; and precipitating the metals formed; or introducing the material into an alkali hydroxide melt in the presence of nitrate as oxidizing agent to form water-soluble ruthenate; subjecting the oxidized melt residue to dissolution in water to obtain a ruthenate solution; treating the ruthenate-containing solution with an oxidizing agent; distilling off of the ruthenate obtained; and absorbing the ruthenate in hydrochloric acid. An independent claim is included for separation (M2) of selenium from materials containing ruthenium or ruthenium oxides or from ruthenium-containing noble metal ore concentrates involving: introducing the material into the alkali hydroxide melt in the presence of nitrate as oxidizing agent and forming the oxidized melt residue with water-soluble ruthenate; subjecting the oxidized melt residue to dissolution in water, where the solution subsequently contains ruthenate and selenate; adding the reducing agent; precipitating water-containing ruthenium(IV) oxide, where the selenium is dissolved quantitatively in second step as selenate.