Hydrometallurgy to Analyze a Chromite Sample
Chromium can be used in the production of stainless steel and other nonferrous alloys in order to enhance their harden ability and to make the alloys more resistant to corrosion and oxidation. It can also be used to plate metals, make pigments, process leather, catalyze, and treat surfaces. Chromite is the only ore of chromium. Chromite is iron magnesium chromium oxide. Metallurgy can be used in order to recover the chromium from the chromite ore.
This experiment is being performed in order to determine if an unknown sample is actually chromite. In order to do this, the sample must be separated using hydrometallurgy. This process consists of extraction of the metal by dissolving the metal in a solvent. The metal must then be recovered and the waste discarded. This can be done by leaching, separating the separating the waste and purifying the leach solution, then precipitating the the metal or one of its pure compounds from the leach solution by chemical or electrolytic mean.
Once this process is done, it can be determined if the sample is actually chromite or not. If the sample contains, magnesium, iron, and chromium, then the sample is indeed chromite. However, if the sample does not contain all of these, then it cannot be chromite.
All participants in the experiment must be wearing safety glasses, long pants, closed toe shoes, and a shirt.
The sample may be mineral chromite. Tests should be done to determine if the sample contains magnesium, iron, and chromium (chromite’s components).
A spectrophotometer may be used to determine if iron and chromium are in the sample, but magnesium neither absorbs nor emits light energy in the 200-900nm region of the spectrum so it can not be determined by a spectrophotometer.
Magnesium must be isolated and precipitated through the process of extraction.
Chromium must be extracted first.
Put 2.5mL of 4.0M NaOH solution into a graduated cylinder.