MINATAUR™: the Mintek alternative technology to gold refining

This paper presents the Minataur™ leach-solvent extraction-precipitation technology developed by Mintek as a cost-effective alternative to traditional gold refining processes. The objective of this study is to detail the operational methodology and advantages of the Minataur™ process, which was first commercialized at the Harmony Gold Refinery. The methodology involves three key operations: dissolution of the feed material through oxidative leaching, selective solvent extraction of gold-chloride species, and the subsequent reduction of gold from an aqueous phase using a suitable reductant. Unlike conventional methods, the Minataur™ process employs a less expensive extractant and eliminates the need for direct precipitation, thus enhancing efficiency and reducing costs. The results demonstrate that the process allows for efficient extraction of gold from various feed materials, producing high-purity gold up to 99.99 percent. Additionally, the technology facilitates the recovery of gold with reduced organic losses and provides an amenable solution for refining jewellery scraps and other gold waste. This work provides insight into the effectiveness and efficiency of the Minataur™ process as a modern solution for gold refining challenges.