I am trying to make a 3 M potassium glycinate solution using equimolar amounts of KOH and glycine. However, my pH ends up too high (~13) and the solution smells of ammonia, indicating that the glycine is hydrolysing or degrading? A huge amount of citric acid is needed to even drop the pH slightly, and the ammonia smell does not seem to go away.
What could be the problem?
Such a high pH exceeds the PKb of NH3, so that matches your observation. Someone else mat know why the NH3 is being released .
Tal Cohen Paul Milham Rajiv .. True.Glycine being an amino acid, is releasing ammonium . Under the KOH induced high pH , this ammonium is being transformed to free ammonia and producing the smell. An weak acid like citric acid is probably acting as a buffer and not being able to reduce the KOH alkalinity substantially to reduce ammonia formation.I am not a competent person in this matter but suggest you to explore the possibility of using some other K compound , in stead of KOH, for preparing K glycinate.The problem is interesting.Please inform if you get a solution.
I'm not sure about the preparation, but may it be possible to use KHCO3 and heat to displace the CO2? An alternative may be K2SO4 to end up precipitating Ba SO4 with K glycinate in soln?
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