Small zirconia/zirconates

Zirconium oxide is used in the production of ceramic colors or stains for ceramic tile and sanitary wares. Zirconia and siHca are fired together to form zircon in the presence of small amounts of other elements which are trapped in the zircon lattice to form colors such as tin—vanadium yellow, praseodymium—zircon yellow [68187-15-5] vanadium—zircon blue [12067-91 -3] iron—zircon pink [68412-79-3] indium—vanadium orange (105—108). 

In 1787 Johann Christian Wiegleb analyzed a zircon from Ceylon and reported only silica, with small amounts of magnesia, lime, and iron (54). Only two years later, Klaproth discovered the earth zirconia in a j argon,... 

Industrial by-products that contain zirconium are mainly zircon and zirconia, both of which are insoluble in water, largely inert, and of low toxicity. Water-soluble zirconium compounds are converted at pH 4-9.5 into insoluble zirconia. The only possible atmospheric emission of other zirconium compounds is that of chlorinated and/or hydrolyzed oxychlorides from the processing of sponge zirconium using the Kroll process (reduction of ZrCl4). Analytical data corresponding to the extent of these emissions do not exist (Smith and Carson 1978), but there is no doubt that the exposure of the general population to zirconium compounds is small. 

After different manufacturing processes only a small part (5%) of this quantity is used for production of zirconium metal and alloys. The main quantity is used as zirconium silicate (the mineral zircon), as zirconia (zirconium oxide) in conventional and advanced ceramic appHcations and for production of zirconium chemicals. 

Stawski, X.M., Besselink, R., Veldhuis, S.A., Castricum, H.L., Blank, D.H.A., and ten Elshof, J.E. (2012) Xime-resolved small angle X-ray scattering study of sol-gel precursor solutions of lead zirconate titanate and zirconia. /. Colloid Interface ScL, 369, 184-192. 

---