28 августа, 2015 
Pokraskin Not all manufacturers produce cadmium oxide, as some prefer to dissolve cadmium metal directly in acid. However cadmium oxide is used in many other applications, including nickel cadmium batteries and stabilizers for polymers.
The oxide can be produced by first melting the metal, then allowing it to flow into a carbon or silicon carbide crucible where, at typically 800 °C, it will boil. The metal vapor is contacted with air by means of an extraction duct positioned over the crucible. A large air flow provided by a fan effects oxidation, and takes the oxide particles to a filtration unit, typically of the reversed jet type, which is a large series of filter bags arranged in a housing. The oxide collects on the outside of the bag while the gases pass through. Intermittent blasts of compressed air into the filter bags expand the bags and cause the oxide to fall off and collect in the bottom of the hopper.
The oxide is then packed and sold, or metered into water to form a slurry suitable for dissolving in acid. Sulfuric acid (50%) is preferred, as the heat of solution is not too violent. In this way, a strong stock solution of about 300 g/L Cd2+ can be produced. The solution is treated as necessary to remove other undesirable metal contaminants, filtered and diluted down to the required strength prior to precipitation.
Clean air from the filter bag housing is typically passed to a scavenger unit to ensure that discharged gases are within permitted limits for cadmium emissions.
3.4.3
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