Development of an environmentally friendly and low-cost leaching procedure for the recovery of gold in sewage sludge

Sofian El Yazidi, Natacha Brion, Marc Elskens

Research output: ThesisMaster's Thesis

Abstract

Due to the importance of metals and precious metals in industrial applications and their limited availability in natural resources and complexity to retrieve them, it is important to find secondary sources for their recovery. This paper focuses on the recovery of gold and platinum from a secondary source that has recently been proven to be rich in precious metals namely sewage sludge. This sewage sludge is a byproduct formed in wastewater treatment plants and forms the starting point for this study. The recovery methods used were leaching with thiosulfate and thiourea and they were chosen because of their relatively low cost and low toxicity, thus being environmentally friendly. During this research, the leaching protocol was optimized with regards to the S/L ratio and the leaching time which resulted in gold extraction efficiencies of 74% for thiosulfate and 68% for thiourea. Further optimization of the leaching protocols is crucial if both methods should be used in industrial applications since the estimated cost for the leaching of 1 oz of gold was calculated to be $16 566 for thiosulfate and $10 699 for thiourea. This cost is much higher than the $919 average all-in sustaining cash cost reported for all gold mines globally that is needed for the recovery of 1 oz of gold from gold mines.
Original languageEnglish
Awarding Institution
  • Vrije Universiteit Brussel
Supervisors/Advisors
  • Elskens, Marc, Supervisor
  • Brion, Natacha, Co-Supervisor
Award date3 Sep 2021
Publication statusPublished - 1 Sep 2021

Fingerprint

Dive into the research topics of 'Development of an environmentally friendly and low-cost leaching procedure for the recovery of gold in sewage sludge'. Together they form a unique fingerprint.

Cite this