Johannes Hermanus (Herman) Potgieter is a visiting research professor in the School of Chemical and Metallurgical Engineering at the University of the Witwatersrand (Wits) in SA. He holds a Ph.D from Wits and Doc.Tech. from Technikon Pretoria (now TUT) and has more than 3 decades of research experience. His research interests cover hydrometallurgy, minerals processing, electrochemistry and water treatment. He is a C.Eng fellow of IOM3 and a member of several other learned and professional societies.