Zirconium perchlorate as cold as possible. Zirconium perchlorate is very hydroscopic forming hydrates, and it is hydrolysed by water to yield zirconyl perchlorate, ZrO(ClO). Zirconium perchlorate reacts with vaseline, methyl nitrate or acetonitrile. Zirconium perchlorate is inert towards carbon tetrachloride, chloroform, and dimethylformamide. Zirconium perchlorate reacts with benzene at 20°C, but at -10°C crystals of Zr(ClO)•CH are deposited. Zirconium perchlorate has solid state transition around 45°C, a melting point between 95.5 and 96.0°C and a decomposition point starting around 120°C. The zirconyl perchlorate formed in the heat decomposition, itself decomposes around 290°C to form zirconia, chlorine and oxygen. In the gas phase
Zirconium alloy zirconium alloys elevates requirement for their resistance to oxidation-related nodular corrosion. Furthermore, oxidative reaction of zirconium with water releases hydrogen gas, which partly diffuses into the alloy and forms zirconium hydrides. The hydrides are less dense and are weaker mechanically than the alloy; their formation results in blistering and cracking of the cladding – a phenomenon known as hydrogen embrittlement. Commercial non-nuclear grade zirconium typically contains 1–5% of hafnium, whose neutron absorption cross-section is 600x that of zirconium. Hafnium must therefore be almost entirely removed (reduced to < 0.02% of the alloy) for reactor applications. Nuclear-grade zirconium alloys contain more