Properties and Overview of Zirconium

Overview:

Zirconium (Zr) is a chemical element with the symbol Zr and atomic number 40. It is a lustrous, gray-white metal known for its strong corrosion resistance. Zirconium is primarily used in high-temperature environments and industries where corrosion resistance is crucial. This element is abundant in the Earth's crust, though it is rarely found in its pure form in nature. Zirconium has a high melting point of 1,855°C and a boiling point of 4,409°C, making it suitable for high-temperature applications. It is relatively lightweight with a density of 6.52 g/cm³. Zirconium is ductile and malleable, allowing it to be formed into various shapes without breaking. Its silvery sheen makes it visually appealing, though it can become brittle when it contains impurities like nitrogen or oxygen.
Zirconium is chemically similar to titanium and is highly corrosion-resistant, particularly by alkalis, acids, seawater, and other agents. It forms stable compounds, with zirconium dioxide (ZrO₂) being one of the most important. Zirconium does not react with water but can react with strong acids like hydrofluoric acid, where it forms soluble zirconium salts. In its compounds, zirconium typically exhibits a +4 oxidation state.
It's important to note that while zirconium is generally considered safe and non-toxic, it's crucial to handle it with care. Fine zirconium dust can pose a fire and explosion hazard, especially in the presence of air. Inhalation of zirconium compounds can cause respiratory issues, so it's vital to ensure adequate ventilation and use protective equipment like masks when handling zirconium powder or working in environments where zirconium dust is present. As with all metals, proper handling and storage are key to preventing accidents.

Production:

Zirconium is mainly extracted from zircon, a mineral widely found in sand deposits. The extraction process involves mining zircon, followed by separation and purification. The Kroll process, which involves reducing zirconium tetrachloride (ZrCl₄) with magnesium, is commonly used to produce pure zirconium metal. Leading producers of zirconium include Australia, South Africa, and the United States.

Applications:

Zirconium's primary use is in nuclear reactors as cladding for fuel rods, thanks to its low neutron-capture cross-section and high corrosion resistance. It is also used in the aerospace industry and for manufacturing high-performance ceramics. Zirconium dioxide (ZrO₂), or zirconia, is employed in making heat-resistant ceramics, dental implants, and protective coatings. Additionally, zirconium alloys are used in chemical processing equipment, and the element is also a component of some catalytic converters and surgical instruments.

Summary:

Zirconium is a versatile and valuable metal, with unique properties such as its resistance to corrosion, high melting point, and lightweight nature, making it essential in nuclear technology, industrial applications, and advanced materials. However, it must be handled carefully to mitigate potential hazards.

See a comprehensive list of atomic, electrical, mechanical, physical and thermal properties for zirconium below: