Preparation of Zirconium Hafnium Bromide Iodide

Preparation of Zirconium (Hafnium) Bromide (Iodide). To prepare a zirconium (hafnium) halide, use a multisection tube made from refractory glass with a test tube and offtake fused to it (Fig.123). 

When preparing zirconium bromide, place 1-2 g of phosphoric anhydride into test tube 1 and through offtake 2 pour in the amount of 

When preparing zirconium iodide, take 20% less iodine than the stoichiometric amount. Place the iodine into test tube 1 and spill a mixture of potassium iodide and freshly prepared calcium oxide (2-3 g) onto it. 

Seal off offtake 2 and spill metallic zirconium into section 5 via offtake 6. Tightly close offtake 6 with a rubber stopper. Connect the apparatus via offtake 8 to a vacuum system for 15-20 min. Next place test tube 1 into a Dewar vacuum flask with liquid nitrogen and seal off offtake 6. Perform this work wearing eye protection in the presence of your instructor ) After the pressure in the system becomes equal to 10 mmHg (in about 40-60 minutes), seal off offtake 8. Stop cooling test tube 1 and wait until the apparatus acquires room temperature. 

Fasten the sealed apparatus in a stand behind the protective window of a fume cupboard wear eye protection ) and slightly heat 

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