domingo, 28 de octubre de 2012

La Importancia Estratégica de Metales y Minerales

High technology’s building blocks
by Guillermo Martínez Funes*
For the Herald
Modern industry demands the use of certain metals and minerals for the development and production of high technology systems. They are generically called strategic minerals and their availability is vital in strategic fields such as aerospace, nuclear, electronic, communications, and oil and gas industries. Without them it would be impossible to built spacecrafts, modern jet engines and structures, rockets and missiles, electronic components, nuclear reactors, high resistance steels and alloys, and special tools and machinery.
The world’s reserves of some of these vital compounds are concentrated in a few countries that can control of their supply.
The number of these minerals may be as high as 90, but explaining the uses of a dozen of them is enough to understand their importance.
1. Chromium
2. Cobalt
3. Nickel
4.Titanium
5. Manganese
6. Cadmium
7. Platinum group
8. Rare earths
9. Zirconium and Hafnium
10. Lithium
Chromium is found as chromite, an iron-chromium oxide, and is an essential component of stainless steel. It forms alloys (with nickel, titanium, aluminum and cobalt), resistant to high temperature, oxidation and corrosion that are used in jet engine casings, turbine blades, high-speed drills, refractory parts, and ball bearings. Four countries produce 85 percent of the world total chromite (23.7 million metric tons): South Africa (46 percent), Kazakhstan (16 percent), India (16 percent) and Turkey (7 percent).
Cobalt is a metal that forms alloys resistant to wear and corrosion that are used in jet engines, high speed tools, magnets, rechargeable battery electrodes, and nuclear control rods. It is also used as catalyst in the chemical and petroleum industries.
The 2010 world’s total cobalt mine production was 89.5,000 metric tons of cobalt content, 53 percent of which was produced by Congo (Kinshasa). Other producers were China (7.3 percent), Russia (6.9 percent) and Zambia (6.4 percent).
Manganese is an important component of special steels, used in machine tools, railroad equipment, and power shovels. It is also used, as manganese dioxide, for dry cell batteries.
In 2010, the world’s production of manganese was 14.2 thousand metric tons, main producers being Australia (21.9 percent South Africa (20.5 percent), China (28.3 percent), Gabon (10 percent) and India (7 percent).
The Platinum group comprises Platinum, Iridium, Osmium, Palladium, Rhodium and Ruthenium. They are byproducts of nickel mining and very expensive elements used only when there are no substitutes. They are used as catalysts in the petroleum and chemical industries.
In 2011, the world platinum production was 195 metric tons. Three countries, South Africa (74.2 percent), Russia (12.8 percent) and Zimbabwe (5.4 percent), accounted for more than 90 percent of the world total production.
Palladium production was 215 metric tons. Two countries concentrate its production: Russia (40 percent) and South Africa (38.2 percent).
Nickel is an important component of stainless steel. In 2010, stainless steel continued to account for more than 60 percent of global primary nickel consumption. It is also used for special alloys (e.g., Inconel 600, for nuclear reactors heat exchangers) and nonferrous alloys (e.g., Cupronickel), turbines for jets and electric power generation stations; and nuclear reactor systems.
In 2010, the world production of nickel ore and other compounds was 1.62 million metric tons of contained nickel. The nickel ore main producers were Indonesia, Australia, Canada, New Caledonia, Brazil and China.
Titanium is a transition metal, paramagnetic, resistant to corrosion and high temperature. It is used in the aerospace industry, as its high strength-to-weight ratio and its melting point of 1,668 C (compared to the 1,500 C melting point of an average steel) makes it an essential component of high technology aircraft and spacecraft. Approximately 95 percent of titanium is consumed in the form of titanium dioxide (TiO2). The Soviet Union used titanium alloys for its submarines hulls.
In 2010, the world production of titanium concentrates, ilmenite and leucoxene, was 6.87 million metric tons, top producers being Australia (24 percent), China (14.6 percent), India (13 percent), and Vietnam (12.8 percent). Another titanium concentrate, rutile, was produced by Australia, South Africa, and Sierra Leone, for an additional 0.71 million metric tons.
Niobium (Columbium) is a transition metal used as component of special steels and superalloys (with Nickel, Cobalt, Hafnium, and Iron) is used for jet engines, liquid rocket thruster nozzles, and high-temperature resistant equipment.
In 2010, the niobium world total production was 62,900 tons. Brazil was the dominant producer with 58,000 tons of niobium content, followed by Canada with 4,400 tons.
Tantalum is a a highly corrosion resistant transition metal used in electronics, machine tools and superalloys for jet engine components.
Three countries, Brazil, Congo (Kinshasa), Mozambique and Rwanda, were the 2010 tantalum main producers, for a world total production of 682 tons of tantalum content.
Cadmium is a metal used mainly in rechargeable nickel-cadmium batteries that can operate in a wide temperature range with a high rate of charge-discharge cycles.
As cadmium telluride, it is used for thin and flexible solar cells. The nuclear industry uses cadmium as a neutron absorber in nuclear reactors’ control rods.
Global production in 2011 was 22.2 thousand tons. Three Asian countries, China, Japan and South Korea were the top producers. About 25 percent of the cadmium production derives from the nickel-cadmium battery recycling.
Vanadium is used as a component of special steels, increasing their toughness at high temperatures. World production in 2011 was 61,200 metric tons of vanadium content, with China, South Africa and Russia as top producers.
Rare earths, also known as Lanthanides, are a group of 15 elements of increasing importance in modern high technology.
Their uses comprise lasers, magnets, luminescent phosphor compounds, precision lenses and fiber optics, electronic counter measures systems, jet engines, missile guidance systems, satellite power units, and telemetry and communications systems.
In 2010, China was the dominant producer of rare earths, with 120,000 tons of rare earths oxide equivalent, followed very far behind by India, with 2.800 tons.
Zirconium is a corrosion-resistant, transition metal that has a high melting point of 1,855 °C. Under the form of its heat-resistant oxide it is used in spacecraft s structure. Its low thermal neutron absorption cross section makes it ideal for nuclear fuel rods cladding, a function it takes in the form of a very special zirconium-based alloy, zircaloy, which usually has up to two percent additions of either tin or niobium. A ceramic, yttrium oxide-stabilized alloy is used to protect high temperature components in gas turbines and jet engines.
Zirconium is also used in the communications industry for the production of fiber optics connectors.
Australia, South Africa, China, Indonesia, India and Mozambique own the world largest zirconium mineral reserves.
Hafnium is usually found along Zirconium and some shared properties such as heat resistance make them suitable components of ceramics. But they grossly differ in one very important property; the thermal neutron absorption cross section of Hafnium is about 600 times that of Zirconium. Therefore they have to be separated through expensive separation processes. While zirconium is used for nuclear fuel rods cladding, hafnium, together with cadmium, is used for neutron-absorbing nuclear control rods. A niobium-based, hafnium-titanium alloy is used in liquid rocket thruster nozzles.
Hafnium-producing countries are the same as those of zirconium.
Lithium is becoming an important strategic element mainly as a component of high energy-density rechargeable lithium-ion batteries. Most of the lithium is produced in Chile, with smaller productions in China and Argentina. Chile and Australia own the world{s main reserves.
These strategic minerals are the building blocks of modern high technology systems and their reserves are concentrated in a few countries in Southern Africa, Central and East Asia, and Australia.
Most of them have very expensive substitutes or have no substitutes at all, and their supply is in the hands of a small number of nations.
*Guillermo Martínez Funes is an engineer and director of www.energyworld.org. He also directs a graduate course on energy geopolitics at EST/IESE, and Belgrano University.

Fuente: Buenos Aires Herald, On Sunday