Preparation
Technical grade V2O5 is produced as a black powder used for the production of vanadium metal and ferrovanadium. A vanadium ore or vanadium-rich residue is treated with sodium carbonate to produce sodium metavanadate, NaVO3. This material is then acidified to pH 2–3 using H2SO4 to yield a precipitate of "red cake" (see above). The red cake is then melted at 690 °C to produce the crude V2O5.
Vanadium(V) oxide is produced when vanadium metal is heated with excess oxygen, but this product is contaminated with other, lower oxides. A more satisfactory laboratory preparation involves the decomposition of ammonium metavanadate at around 200 °C:
- 2 NH4VO3 → V2O5 + 2 NH3 + H2O
Read more about this topic: Vanadium(V) Oxide
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