Case: Hg2+ is adsorbed on a titanium carbide and 0.1 M HCl/HNO3 is used for the desorption of Hg2+. During the reaction, the solution turns into a pale yellow color. I want to understand what sort of reaction is going on there.
Note: the adsorbent is stable in 0.1M HCl/HNO3 and there is such coloring in the control experiment.
Good morning, are you observing the same coloring in the control experiment as well. If the control experiment done have pale yellow coloration then there might be interference from adsorbent material. If not there might be the formation of calomel due to released Hg2+ and free cl- ions. It is also important to measure the released Hg2+. However, the kind of adsorption also plays an important role, if there is chemisorption the release will be less and physisorption release will high.
Mercury does not react with dil. HCl but reacts with HNO3. Hg (ll) reacts with HNO3 and changes into mercury nitrate, mercurous nitrate Hg 2 (NO3)2. Pale yellow color may be due to other materials
Thank you Prof. Kadam for responding, I have checked the adsorbent is stable in 0.1M HCl/HNO3 because the solution is colorless. Regarding the release of mercury, there is only 3-5% desorption of mercury in 0.1M HCl/HNO3 solution, whereas EDTA resulted in 100% desorption (and there is no color in the case of EDTA).
- Badges
- Science topic