Dysprosium bromate

Yttrium is one of the most abundant rare earth elements and its purification is easily accomplished. Yttrium fractions from a bromate series are freed from dysprosium, holmium, and erbium by fractional precipitation with ammonia, K2OO4, or NaNC>2. The latter is probably the most effective. Yttrium salts give no absorption lines ini the viable portion of the spectrum, consequently the removal of holmium and erbium is easily observed by the direct vision spectroscope. 

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