Journal of Mining and Metallurgy, 41 B (2005) 17 - 32J. Min. Met. 41 B (2005) TEACHING AND LEARNINGADAPTIVE HYDROMETALLURGY-NANOHYDROMETALLURGYB. Peši}#Department of Materials Science and Engineering, College of Engineering, University of Idaho, Mc Clure Hall, Moscow, ID 83844-3024, USA(Received 29 December 2004; accepted 20 January 2005)AbstractThe weakness of the U.S. mining industry has caused a significant decline in academicprograms in mining and metallurgical engineering in the U.S. The author’s view on thereasons for such weaknesses is presented in a historical prospective covering some key eventswithin the last 30 years. Arguably, the decline of U.S. mining industry is due to many reasons,the most important being the lack of modernization, the difficulty to comply with stringentenvironmental laws, and global market forces, are the most important. The importance ofemerging nanotechnologies is viewed as an opportunity for the evolution of one component ofmetallurgical engineering— hydrometallurgy—into nanohydrometallurgy, thus extending itsviability.Keywords: Please provide 4-5 keywords1. IntroductionExtractive metallurgy has three components with overlapping aspects:# Corresponding author: [email protected] New.qxd 12/6/2005 7:09 PM Page 1B. Pe{i}J. Min. Met. 41 B (2005)18hydrometallurgy, pyrometallurgy, and electrometallurgy. In combination withpyrometallurgy, hydrometallurgy is an important contributor to the foundationof every extractive metallurgy academic program. As the name suggests,hydrometallurgy as an extractive metallurgy discipline involves the recoveryof metals by wet methods, i.e. from aqueous solutions. The third contributorto the extractive metallurgy—electrometallurgy—can also be regarded as asubset of hydrometallurgy, if electrowinning and/or electrorefining of metalsis performed from aqueous solutions. If, however, these two electrometallur-gical operations are performed from molten salts, requiring much higherprocessing temperatures, then electrometallurgy may also be classified aspyrometallurgy. (It is not uncommon to hear aluminum electrometallurgicalplants referred to as smelters, for example.) Some consider electrometallurgyto be a stand-alone extractive metallurgy discipline. Hydrometallurgy involves various processing steps, such as dissolution,separation, concentration, purification, and metal winning. Except forseparation, which may be physical, each of these steps relies on the chemicalprinciples of oxidation, reduction, solvation, chelation, hydrolysis, etc.Dissolution of metals, ores, and concentrates is usually the first step in atypical hydrometallurgical flowsheet, followed by physical separation ofphases, most likely by filtration. Solution purification and concentration stepsmay involve precipitation, solvent extraction, and ion exchange chemistries.Winning of metals from solutions is most widely achieved by electroreductionin an electrowinning process, or by other reduction methods, e.g. utilization ofgaseous reductants, such as hydrogen, sulfur dioxide, etc.It is important to recognize that each of the above processing steps is alsofound in traditional analytical chemistry (qualitative and quantitative); thus itis possible to regard hydrometallurgy as applied analytical chemistry, the soledifference being the scale of the involved steps. The identification withanalytical chemistry suggests that the solutions to the relevant industrial unitoperations may be found in the procedures already developed by analyticalchemists.In the academic world, all hydrometallurgy courses belong to schools withstrong mining and extractive metallurgy programs, the strength of which istied directly to the strength of the mining industry. Due to the ongoingeconomic globalization the strength of the mining industry has substantiallyBPesic New.qxd 12/6/2005 7:09 PM Page 2Teaching and learning adaptive hydromellurgy-nanohydrometallurgy J. Min. Met. 41 B (2005) 19changed. In some countries, the mining industry has been growing; in others,such as the U.S., the mining industry is struggling for survival. Consequently,many mining schools in this country have been shut down, or barely exist.From the extractive metallurgy (more specifically hydrometallurgy) teachingpoint of view, it is difficult to maintain the programs in the traditional formunless some programmatic modifications have been implemented.Hydrometallurgy must transform and adapt to the current industrial climate inorder to protect its own viability.2. Possible Reasons for a Demise of Mining/Extractive Metallurgy in the U.S.A.Perhaps the turning point for the health of U.S. Mining Industry can betraced back to the 1970s. This decade was politically turbulent (the end of aVietnam war, the ongoing ‘cold war’, the Middle East instability), alsocharacterized by severe price instability for raw materials, such as oil,minerals and metals. The high oil prices made many U.S. oil corporationsextremely rich. Having achieved control of oil as an important energyresource, the oil corporations boldly moved to control another strategicallyimportant resource: minerals. With plenty of cash at hand, major oilcorporations went on a shopping spree, buying one mining corporation afteranother. For example:- Anaconda was purchased by Atlantic Richfield Corporation (ARCO) in 1977.- Standard Oil of Ohio (SOHIO) bought out Kennecott in 1981.- Gulf Resources controlled the Bunker Hill Mine. - Duval Corporation, a textbook example for copper production based entirely on hydrometallurgical principles, was controlled by Pennzoil. The ‘70s saw exceptional economic volatility, reflected in oil and metalprices [1]. The year of 1973 was the year of greatest economic activity, onlyto be followed by a severe recession in 1975, with the oil embargo during1974 being its major culprit. The 1976 and 1977 were years of rapidBPesic New.qxd 12/6/2005 7:09 PM Page 3B. Pe{i}J. Min. Met. 41 B (2005)20economic recovery. The 1970s have another important event: the birth andgrowth of the U.S. Environmental Protection Agency (EPA) [2]. The early1980s were characterized by yet with another severe recession. Flanked byrecessionary effects on one side and by the EPA on another, the oilcorporations began losing the interest in the metals business. Not keen oninvesting in the new processing technologies to comply with the tightenedEPA standards, the oil corporations shut down