86 JOURNAIv OF THE 



Applied Chem. VoL Vp. SS^]- Bailey's method [/o/^r;/. 

 London Cheni. Trans. iSS6, p. i^g] of precipi- 

 tation by means of hydrogen peroxide is very expen- 

 sive, aside from the difficulties one encounters in pre- 

 paring- the reag-ent pure. 



Having* learned that zirconium could be precipitated 

 completely, freed from iron and aluminium, [Baskerville 

 J. A??i. Cheni. Soc. XVI, p. 475.] by means of sulphu- 

 rous acid, when working* with the small amounts usually 

 employed in analysis, I proposed to apply the same 

 treatment to quantities in bulk for the purpose of 

 obtaining* a pure salt of zirconium. 



The powdered zircon, washed with hydrochloric acid, 

 (100 g*rams) w^as fused and treated according* to the 

 directions g*iven by Venable \loc. c/L] up to the point 

 where the impure zirconium chloride had been freed 

 from silicic acid and was in a dilute hydrochloric 

 acid solution. 



This solution was nearly neutralized with ammo- 

 nium hydroxide. A strong* stream of washed sulphur 

 dioxide g*as was then led into the cold solution to thor- 

 ough saturation. This required about fifteen minutes. 

 Partial precipitation occurred in the cold, but other 

 experiments had shown that the precipitation would be 

 more complete if this solution saturated with sulphur 

 dioxide was diluted largely and boiled. Five to ten times 

 as much distilled water was accordingly added and 

 the whole boiled half an hour in larg'e evaporating 

 dishes. The zirconium precipitated out and settled 

 nicely. No bumping occurred during the cooking — 

 while hot, the liquid w^as rapidly gotten away by 

 means of an unglazed porcelain suction filter. The 

 precipitate was washed two or three times with 

 hot water, then boiled in water and again washed after 



