Strategic metals

Cote, G. Hydrometallurgy of strategic metals. Solvent Extr. Ion Exch. 2000, 18, 703-727. 

Another issue with metals is availability. For example, cobalt is not produced in the United States, but it used extensively in a wide variety of alloys and in the production of one of the most common types of lithium batteries. The availability of cobalt is crucial to several segments of American industry. For example, batteries being developed for use in automobiles powered by alternate energy sources are currently envisioned to use a lithium ion battery that also contains cobalt. However, cobalt is not the only strategic metal, and there is concern about the availability of several metals that are vital to industries in the United States, China, and Japan. There will be competition and stockpiling of strategic metals as the reserves become less accessible. 

Other areas of geologic research that can be explored using a combined instrumentation approach are many. Surface reactions of solids that have been suspended in aqueous solutions can be studied this type of work has important applications in mineral processing research. The analysis of precious and strategic metal ores can be studied in order to monitor their inherent material and chemical properties and their surface characteristics before and after reaction. 

Organophosphorus acid extractants have found considerable use in recent years for the recovery of uranium as a byproduct in the manufacture of wet-process phosphoric acid. This acid is obtained by the digestion of phosphate rock with sulfuric acid, and typically contains 0.1 to 0.2 g of uranium per litre.120 It has been estimated that, in 1976, the wet-process acid produced in the USA alone contained some 2500t of dissolved uranium 121 this therefore represents a valuable potential source of this strategic metal. 

Strategic Metals Recovery Research Facility, Department of Chemistry, University of Arizona, Tucson, AZ 85721... 

Wenrich, K.J. and Silberman, M.L. (1984) Potential precious and strategic metals as by-products of uranium mineralized breccia pipes in northern Arizona. AAPG Bulletin, 68(7), 954. 

Such a diversity of structural positions enables seafloor manganese nodule deposits to enrich a variety of strategic metals. 

In all these instances, a cartridge may either be consumed in its entirety or for ballistic reasons a metal base used, leading to a partially combustible case. The advantages of a combustible case are obvious. Enormous amounts of strategic metal would be released for other purposes and there is no question of collection and reuse of such metal. Special benefits are derived for the gunner within a tank The hot used metal cases are an encumbrance in the close quarters, and residual toxic gases from burned propellant powder remain in the conventional metal cases. 

NDSX techniques have been deployed in separation science applications such as metal recovery from leach solutions, recovery of precious and strategic metals, and treatment of large volumes of effluents including toxic and hazardous waste generated by chemical industries [33-36]. Recovery of Sb, Cu, and Zn from industrial waste has been reported using NDSX method [37,38]. 

This work has been carried out by a group at Texas Tech University, within the Department of Chemistry and Biochemistry and the Strategic Metals Recovery Research Center, under the leadership of Professor D. Max Roundhill. The effort there has focused upon developing both computational and experimental strategies related to the safe removal and processing of nuclear materials. The group has collaborative interactions with both LANL, in conjunction with the ANRCP, and the Pacific Northwest Laboratory (PNL). 

It should also be emphasized the ecological aspects inherent to biofuel cells that contrarily to fuel cells, require no metal catalysts (platinum, nickel, palladium, rhodium, iridium, etc.). Indeed, materials, fuels, and products used in the design of all biofuel cells are biodegradable. Consequently, these biofuel cells are not subjected to major economic issues related to metal catalyst. Indeed, the increasing demand for strategic metals and metal alloys by high-tech industries, aerospace or automotive industry causes a process of depletion of these materials. 

Strategic Metals Ltd Amersham, Buckinghamshire, UK www.strategicmetals.co.uk/ Fax +44 (0) 1494 581159 M0S2 powder in various grades... 

A third conclusion that may be deduced from Fig. 10.15b is that there is a difference of 0.18 V between the overall average Fonset for the N-doped carbons catalysts prepared with Fe or Co in their synthesis (dark square) and the N-doped carbons obtained without either Fe or Co (open square). The latter may not seem large, but in fact means that a N-doped carbon made with a strategic metal will be able to generate (at about 0.8 V vs. RHE) = 63 times more current... 

The reason for this factor of about 60 in ORR activity between the two types of N-doped carbon catalysts, i.e., N-doped carbons made with strategic metals like Fe or Co and those made without any strategic metal, is what divides the scientific community. One camp believes the presence of Fe-Nx or Co-Nx catalytic sites explains the drastic improvement while the other defends the hypothesis that a larger number of N atoms (pyridinic or graphitic) or a larger number of graphene edges catalyzed by Fe or Co is what explains the difference. 

We have shown several examples in this chapter where residual strategic metals contents <0.2 wt% (Fe or Co) in N-doped catalysts, considered negligible by some researchers, can in fact result in non-negligible catalytic activity for ORR in acid medium, given that this activity increases quickly with the Fe or Co content in N-doped catalysts (see Figs. 10.3 and 10.16b). We also believe that the existence of Fe-Nx sites in Fe/N/C catalysts have now been proven with little or no doubt by ToF-SIMS, Mossbauer spectroscopy, STEM imaging and EELS analysis, and by some carefully performed poisoning experiments. These four types of proofs are now discussed. 

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