Zirconium Arsenates

Zirconium Orthoarsenate, Zr₃(AsO₄)₄.5H₂O, has been obtained as a voluminous white precipitate by adding sodium monohydrogen orthoarsenate to a solution of zirconyl fluoride in hydrochloric acid. Zirconium monohydrogen orthoarsenate, Zr(HAsO₄)₂, appears to be formed slowly by adsorption of arsenic acid by zirconium dioxide.

Zirconyl Pyroarsenate, (ZrO)₂As₂O₇.nH₂O, is obtained as a white precipitate when sodium monohydrogen orthoarsenate is added to a solution of zirconium sulphate. When dried at 110° C. the monohydrate, (ZrO)₂As₂O₇.H₂O, remains. It is insoluble in water, but readily dissolves in hydrochloric acid.