Sources and Uses of Zirconium Element

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Natural silicate ores containing zirconium are known as zircon or hyacinth, widely distributing in the nature. They are called as gems since ancient times for their beautiful colors. Chemists analyze zircon and find that zircon is an oxide containing silicon, aluminum, calcium and iron. In 1789, Klaproth, a German chemist, published the report on the study of the zircon from Sri Lanka. As the report mentioned, he found an unknown oxide which is unique and simple, and he proposed to name it Zirconerde. Soon, Dermouval and Vauquelin, two French chemists both proved that Klaproth’s analysis is correct. Therefore, Zirconerde is confirmed and gets its name as zirconium and its symbol as Zr.

Zirconium is generally regarded as rare metals. In fact, its content in the Earth’s crust is quite large, exceeding common metals such as zinc, copper, tin, etc. Initial study of zirconium silicate experimental operation by Klaproth until today is still the basis for the extraction of zirconium in the industry. Until 1914, pure zirconium metal is obtained when zirconium tetrachloride reacts with sodium metal by two researchers Leli and Humburg from a factory producing metal incandescent lamp in Holland.

Zirconium metal looks like steel, but zirconium metal powder is dark grey. At room temperature, the surface is usually covered with a dense oxide layer, but there is still a metallic luster. Its melting point is 1,852°C with density of 6.49 g/cm3. For its good plasticity, zirconium is easy to process into the plate, wire, etc. As zirconium can absorb oxygen, hydrogen, nitrogen and other gases in large quantities when heating, it can be used as hydrogen storage materials. Corrosion resistance of zirconium is better than that of titanium, close to that of niobium and tantalum. Zirconium and hafnium are similar in chemical property and they have a symbiosis with radioactive material. Zirconium’s content ranked 20th in the Earth’s crust, almost equal to that of the chrome. Currently, zircon and baddeleyite are mainly zirconium-containing minerals of industrial value in the nature.

With small capture cross section and prominent nuclear capability, zirconium’s thermal neutron is indispensable materials for the development of atomic energy industry, and can be used for structural materials for the reactor core. Zirconium powder is flammable in the air so that it can be used for detonators and smokeless gunpowder. Zirconium can be as additives for stainless steel to achieve deoxy desulphurization, and it also can be as components for stainless steel, heat-resistant steel, armoured steel and steel for cannons. Zirconium is an important alloying element for the magnesium alloy, and it can improve tensile strength and process ability of magnesium alloy. As modifier of aluminum-magnesium alloy, zirconium can refine the grain. Zirconium dioxide and zircon are the most valuable refractory compounds. Zirconium dioxide is a new and major ceramic material, and it can not be used as heating material to resistant to high oxidation. Zirconium dioxide can be used as acid-resistant enamel and glass additives, and can significantly improve flexibility, chemical stability and heat resistance of the glass. Zircon has strong light reflection and good thermal stability, so it can be used as sunscreens for ceramics and glass. With heating, zirconium can absorb a large amount of oxygen, hydrogen, ammonia and other gases, so it is the ideal getter. For example, zirconium powder can be used for degassing agent of tubes, and zirconium wire and sheet can be used for gate bracket and anode bracket.

Flash powder can be made from powdered iron mixing with zirconium nitrate. Almost all of the zirconium metal is used for the cladding of uranium fuel element in nuclear reactors. It is also used for manufacture of photographic flash, and corrosion-resistance containers and piping, particularly resistant to hydrochloric acid and sulfuric acid. Besides, its chemicals can be used as a cross linking agent for the polymer.

Production of Zirconium:

Zircon sand is main raw material of zirconium products. China produces 90%of global zirconium oxychloride (primary products). Currently, China can process zirconium of 120,000 tons per year, with actual production at 80,000 tons per year, of which, more than 85% for export. Now, the demand for zirconium exceeds the supply in the global market. Therefore, the unit price of zirconium continues to rise.