Improvement of the solvent extraction of rhenium from molybdenite roasting dust leaching solution using counter-current extraction by a mixer-settler extractor

Continuous counter-current extraction of rhenium from roasting dust leach liquor was carried out using a mixer-settler extractor. Tributylphosphate was used as the extractant diluted in kerosene. The effects of the flow rates and extraction stages were investigated. The extraction efficiency was affected by the flow rates of the aqueous and organic phases, and its mechanism was qualitatively discussed on the basis of the stoichiometric relations of the extraction. Rhenium extraction mass balance and simulation in the mixer-settler was also studied. A high rhenium extraction percentage (95.43%) in the phase ratio 1:1 was achieved using a counter-current four-stage extraction process. The continuous counter-current extraction technique was used in this research work showed to be effective for rhenium extraction from the leach solutions of the dust of the molybdenite roasting furnaces.