Recovery of Gold from Radioactive Gold Waste Using The Redox Replacement Method with Zn-Foil Reductor

The residual waste of synthesis and use of radioactive elements of gold Au-198 as a radiopharmaceutical and tracer after decaying can be reused as an irradiated target material. The gold recovery process was carried out on Au-198 radioactive nano gold waste with the redox replacement method using Zn-foil as metal reducing agent. Radioactive Au-gold waste was stored until it decayed to its background, so it is not dangerous and does not interfere with the optical characterization process. The sample was dissolved with aquaregia and evaporated so that the chelating or dendrimer material can be released and oxidized. The evaporation was done to reduce acidity and obtain the salt. Furthermore, the salt solution of HAuCl4 is reduced with Zn-foil so that the pure gold deposits can be obtained through a redox process. The results of the XRF analysis showed that the gold deposits formed have fairly good purity with little Zn and Zr impurities derived from the erosion of the melting container. The yield calculation results based on ICP-OES data obtained a recovery percentage of 68.73%. The method of taking gold deposits must be increased to reduce the gold particles attached to the bar stirrer and to the melting pottery container.