METHYL ISOBUTYL KETONE

Abstract

Reactor grade zirconium is required to keep hafnium content below 0. 01% (as metal ratio). However, zircon (ZrSiO//4), a major source of zirconium, contains about 2. 5% hafnium (as metal ratio), and it is extremely difficult to remove 99. 7% of hafnium from the material, because of similar chemical properties of zirconium and hafnium. Experience acquired in industrial production of about 600 tons of hafnium-free zirconium oxide by title process is discussed.