Bachelor theses / Master theses / Diploma theses

The r4 project "Theisenschlamm" deals with the processing of a production residue of the former copper shale processing in the Mansfeld region (Germany). In addition to larger amounts of zinc and lead, this material also contains small concentrations of e.g. molybdenum. The first step of the hydrometallurgical processing is leaching of the Theisenschlamm. Recovery and enrichment of molybdenum from the leaching solution is achieved by solvent extraction. Due to its selectivity the extractant Cyanex 272 is particularly suitable for molybdenum.
In order to further characterize and optimize this extraction system, the influence of the extracting agent (0.05 - 0.5 mol/L) and molybdenum concentration (0.1 - 2 g/L) as well as the influence of the pH-value (0 < pH < 2.5) on the extraction of molybdenum are to be determined by constructing the respective extraction isotherms. Furthermore, extraction isotherms for scrubbing (selective removal of co-extracted elements from the organic phase) of e.g. iron and zinc with sulphuric acid as well as stripping (back-extraction into an aqueous phase) of molybdenum with ammonium hydroxide or ammonium carbonate are to be determined. The data for construction of the isotherms is obtained by mixing the organic and aqueous phases at different phase ratios in the range of 1:10 to 10:1 until the chemical equilibrium is reached. The experiments will be carried out in 15 or 50 mL tubes.

• Study programme in the fields of process engineering, industrial chemistry, metallurgy or similar courses of studies
• Basic knowledge about metallurgical processes, especially solvent extraction, is favourable
• Basic knowledge in conducting experimental investigations in laboratories as well as the scientific interpretation
• Ability to work independently

• Start: April 1st, 2018
• Place of work: Freiberg
• Paid according to HZDR guidelines