Sciencemadness Discussion Board

Converting Pyridine HCl Powder to Pyridine?

xobon - 25-7-2012 at 14:25


Is there a way to convert pyridine hcl powder to pure pyridine (solvent)?

kristofvagyok - 25-7-2012 at 14:33

Add some solid sodium/potassium hydroxide, a little water and distill the resulting liquid.

Abs. pyridine could be made by adding molten KOH to relative anhydrous pyridine.

But if you had no idea how should this made, I would suggest to learn a bit more from chemistry and start the "experimental" part after that.

[Edited on 25-7-2012 by kristofvagyok]

xobon - 25-7-2012 at 14:47

What should be the ratios?

For example, 100g Pyridine HCl to how many grams of NaOH and how many ml of H20? Will the distillate be pure Pyridine, or should I use a distillation column to separate the distillates?

At what temperature should it be heated for distillation? Should it be under vacuum?

gypsyNo2 - 26-7-2012 at 05:30

you will need to heat it up past pyridines boiling point to get it to distill over. Water is a biproduct of of the "neutralisation" process so I wouldn't add too much. Maybe dissolve your pyridine salt into the water and add it to KOH pellets.

It might just be worth adding X number of moles of pyridine HCL to 1.2 mol excess of KOH mix it up, start distillation, discard the distillates until vapour temp reaches bp of pyridine (115 or so from memory but don't quote me) and distill into a flask and stor over KOH pellets until needed.

Good Luck

G.No.2