KNUST Research Week and Scientific Conference: Empowering Researchers to Achieve Impactful Outcomes

Ghana’s gold mining sector plays a crucial role in national economic development with fire assay method serving as a technique for accurate determination of precious metal content. One key component of this process is the use of cupels, a small porous ceramic material used in cupellation process to quantify the amount of Gold present in ore. As part of the process, lead metal is absorbed into the cupel in a form of lead oxide leaving gold and silver prill as a solid. This reasearch aims to analyse the physical, chemical and mineralogical features of both unspent and spent cupels from three mine assay laboratories in Ghana. Mass fraction showed significant negative correlation with unspent cupel weight (p=0.012) and positive correlation with weight difference. Lead was found to be averagely 28 wt% in spent cupels. Analytical techniques were used and the results revealed variations in mineral and elemental phase in unspent and spent cupel from the selected mine assay laboratories which influences the performance and also its environmental impact. Building on these features, practical recovery of the lead using green solvent for selective leaching followed by sodium carbonate precipitation of lead as lead carbonate. The remaining MgO rich residue has potentials to be used for non-assay materials such as ceramic and composite fillers. This approach reduces hazardous load. This research connect material characterization to process design giving assay laboratories a realistic pathway to divert waste as well as recover value and promote sustainable mining practices.