Development of an efficient e-waste recycling and beneficiation method into separable precious metals

• Published in: E3S web of conferences 2024-01, Vol.505, p.1036
• Main Authors: Nkhoma, Richard, Ngonda, Tiyamike, Mwale, Vincent Dodoma, Falayi, Thabo, Siyasiya, Charles
• Format: Article
• Language: English
• ISSN: 2267-1242; 2267-1242
• DOI: 10.1051/e3sconf/202450501036

The issue of e-waste recycling is the uncharted territory in in most developing countries with a full potential to be a source of secondary resources. Every year there are tonnes of electronic materials with precious metals in them that lie in the landfills as there are no economically viable methods to extract them. Many people have attempted to recover precious metals from e-waste and the challenge is to come up with a method that is fast, clean (environmentally friendly), cheap and safe. The aim of the research was to recover precious metals that are of high value such as gold using hydrometallurgical methods. To achieve the faster reaction rate, the process involved heating H 2 SO 4 to about 70±10°C and then washing with water after using a 1:1 solution of water to HNO 3 to get rid of other remaining metals. Afterwards, a 10:1 ratio of HCl to H 2 O 2 was added in order to strip the components of gold. Precipitation of the gold solution was done using Na 2 S 2 O 5 and left for 4 hrs to settle. The final result, after precipitating and drying , showed that with the devised method, it is possible to recover gold at a shortest possible period of 4 days.