Abstract: A process for the treatment of acidic wastewater which comprises hydrochloric acid, nitric acid as an optional component, 0.1 to 30 wt.-% of one or more dissolved metals selected from the group consisting of aluminum and heavy metals other than precious metals, and 10 to 500 wt.

Abstract: A process for the treatment of acidic wastewater which comprises hydrochloric acid, nitric acid as an optional component, 0.1 to 30 wt.-% of one or more dissolved metals selected from the group consisting of aluminum and heavy metals other than precious metals, and 10 to 500 wt.

Abstract: A recycling furnace is provided for processing potentially explosive precious metal-containing materials having organic fractions that combust with great energy. The furnace includes a switching facility for alternating operation of two burning-off chambers of the furnace between: (A) pyrolysis or carbonization under protective furnace gas in an atmosphere comprising maximally 6 wt-% oxygen, and (B) oxidative combustion of the organic fractions including carbon. The furnace has indirect heating and a control that determines the end of the pyrolysis or carbonization by a sensor and controls the switching facility to supply air or oxygen to the interior of the furnace. A continuous conveyor for dosing of liquids or liquefied substances during the pyrolysis is controlled by at least one parameter of post-combustion, preferably a temperature sensor. A single waste gas treatment facility is used for thermal post-combustion for the two furnace chambers.

Abstract: A recycling furnace is provided for processing potentially explosive precious metal-containing materials having organic fractions that combust with great energy. The furnace includes a switching facility for alternating operation of two burning-off chambers of the furnace between: (A) pyrolysis or carbonization under protective furnace gas in an atmosphere comprising maximally 6 wt-% oxygen, and (B) oxidative combustion of the organic fractions including carbon. The furnace has indirect heating and a control that determines the end of the pyrolysis or carbonization by a sensor and controls the switching facility to supply air or oxygen to the interior of the furnace. A continuous conveyor for dosing of liquids or liquefied substances during the pyrolysis is controlled by at least one parameter of post-combustion, preferably a temperature sensor. A single waste gas treatment facility is used for thermal post-combustion for the two furnace chambers.

Abstract: Processes for the recovery of ruthenium from materials containing ruthenium or ruthenium oxides or from ruthenium-containing noble metal ore concentrates, with the steps of A. 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 of 5C 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.

Abstract: A recycling furnace and method are provided for processing potentially explosive precious metal-containing materials having organic fractions that combust with great energy, the furnace including a switching facility for alternating operation of a burning-off chamber of the furnace between: (A) pyrolysis or carbonization under protective furnace gas in an atmosphere comprising maximally 6 wt-% oxygen, and (B) oxidative combustion of the organic fractions including carbon. The furnace has indirect heating and a control that determines the end of the pyrolysis or carbonization by a sensor and controls the switching facility to supply air or oxygen to the interior of the furnace. Steps (A) and (B) are carried out sequentially in the furnace chamber, wherein neither the batch is changed, nor the furnace is opened. After the end of step (A) is determined, step (B) proceeds right after the pyrolysis or carbonization by supplying air or oxygen.

Abstract: Processes for the recovery of ruthenium from materials containing ruthenium or ruthenium oxides or from ruthenium-containing noble metal ore concentrates, with the steps of A. the introduction of the material into a highly alkaline alkali hydroxide melt in the presence of nitrate as oxidising agent with the formation of an oxidised melt residue with water-soluble ruthenate (RuO4)2-, B. the dissolution of the oxidised 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 of 5C the treatment of the ruthenate-containing solution with an oxidising 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.

Abstract: Processes for the recovery of ruthenium from materials containing ruthenium or ruthenium oxides or from ruthenium-containing noble metal ore concentrates, with the steps of A. the introduction of the material into a highly alkaline alkali hydroxide melt in the presence of nitrate as oxidising agent with the formation of an oxidised melt residue with water-soluble ruthenate (RuO4)2?, B. the dissolution of the oxidised 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 of 5C the treatment of the ruthenate-containing solution with an oxidising 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.

Abstract: A recycling furnace and method are provided for processing potentially explosive precious metal-containing materials having organic fractions that combust with great energy, the furnace including a switching facility for alternating operation of a burning-off chamber of the furnace between: (A) pyrolysis or carbonization under protective furnace gas in an atmosphere comprising maximally 6 wt-% oxygen, and (B) oxidative combustion of the organic fractions including carbon. The furnace has indirect heating and a control that determines the end of the pyrolysis or carbonization by a sensor and controls the switching facility to supply air or oxygen to the interior of the furnace. Steps (A) and (B) are carried out sequentially in the furnace chamber, wherein neither the batch is changed, nor the furnace is opened. After the end of step (A) is determined, step (B) proceeds right after the pyrolysis or carbonization by supplying air or oxygen.