Innovations in Hydrometallurgical and Electrometallurgical Processing: A TMS2012 Symposium Sampling

Abstract

Hydrometallurgical and electrometallurgical processing is becoming more common in a variety of industrial applications. In metal extraction, technologies such as solvent extraction have helped to facilitate large-scale, low-grade extraction of metals such as copper by hydrometallurgical processing, which is followed by electrometallurgical recovery. In other areas, hydrometallurgical and electrometallurgical technologies are being utilized to enable recycling and by-product recovery of metals and metal compounds. Improvements in technologies have been applied to the development of resources in common as well as rare metals that would not otherwise be possible. The use of hydrometallurgical and electrometallurgical technologies is increasing; as the world demand for metals increases, the natural resources become lower in grade and more challenging to process, and the need to recycle metals to conserve resources and energy grows. Hydrometallurgical processing has been used to enable the large-scale extraction and recovery of many metals. Most metals, including relatively inert metals such as gold and platinum, can be extracted, processed, and recovered using aqueous solutions. The availability of water and the interaction and amenability of metal processing in water-based solutions makes hydrometallurgical processing an attractive method for the processing of many metals, many of which come from ore bodies that were formed in part by hydrometallurgical processing in the Earth’s crust. Some of the main challenges that face hydrometallurgical processing include energy utilization, environmental viability, chemistry limitations, and separation technologies. Electrolytic processing is used commercially to recover and/or refine metals that include large-scale production for aluminum, copper, magnesium, nickel, and zinc. In addition, electrometallurgical processing is used on a smaller scale for recovery and refining of gold and silver. There are also exciting opportunities to utilize electrometallurgy in the production of titanium, lead, and other metals. Electrolytic processing of metals faces common challenges that include energy utilization, chemistry, productivity, and safety. To meet the present challenges in commercial electrometallurgy, a variety of technological advances have been made. Similar challenges will be faced in the future, requiring process improvements and innovations. Two international symposia covering hydrometallurgy and electrometallurgy topics were held at the TMS2012 Annual Meeting in Orlando, Florida. The T.T. Chen Symposium was held in honor of T.T. Chen, who has made great contributions to the scientific and industrial communities in materials characterization, electrometallurgy, and hydrometallurgy. Tzong T. Chen, or T.T. as he is often called, is an Emeritus Scientist, who has worked for CANMET for the past 38 years, where he has served the global metallurgical industry through his application of mineralogical methods to evaluate metallurgical processes and to assist with their development. Chenite, as shown in Fig. 1, a photo of the blue crystals, Pb4Cu(SO4)2(OH)6, was named in honor of Chen. To celebrate Chen’s outstanding contributions to the science and practice of extractive metallurgy and especially to honor his pioneering studies on the characterization of metallurgical products, Shijie Wang and several friends and colleagues organized the T.T. Chen Honorary Symposium on Hydrometallurgy, Electrometallurgy and Materials Characterization that was held at the TMS2012 Annual Meeting. Many individuals from the world’s metallurgical community saluted Dr. Chen for his numerous scientific achievements at this event. There were 69 presentations in eight sessions, and 76 papers, including the poster session, were included in the published proceedings. The symposium included plenary session, Copper JOM