Zirconium Peroxide and Perzirconates

Cleve prepared a hydrated zirconium peroxide, supposed to be ZrO₃.nH₂O, by precipitating with ammonia a mixture of zirconium sulphate solution and hydrogen peroxide; and Bailey obtained a gelatinous precipitate which he believed to be hydrated Zr₂O₅, by adding hydrogen peroxide to a neutral solution of zirconium sulphate.

More recently Pissarjewski has investigated the action of hydrogen peroxide and of sodium hypochlorite on hydrated zirconia, and represents the reactions in the following way:

Zr(OH)₄ + H(O₂H) = Zr(O₂H)(OH)₃ + H₂O.
Zr(OH)₄ + NaOCl = Zr(O₂H)(OH)₃ + NaCl.

It is noteworthy that hydrogen peroxide and sodium hypochlorite, which usually differ widely in oxidising action, are here represented as yielding identical oxidation products. From this it is argued that the product is really a derivative of ZrO₃ and not the double compound Zr(OH)₄.H₂O₂.

No precipitate is obtained on adding hydrogen peroxide to a zirconium salt solution in presence of sodium or potassium hydroxide, because the alkali perzirconates are soluble salts. Salts having the formula Na₄Zr₂O₁₁.9H₂O and K₄Zr₂O₁₁.9H₂O respectively are obtained by dissolving zirconium peroxide in alkaline hydrogen peroxide solution and precipitating with alcohol.