Mix 300 g of niacin and 4.6 g of copper chromite catalyst pour them into 1 L RBF distillation apparatus. Heat to 110°C and the pyridine starts to distill, some niacin will sublime. If a lot of the niacin starts to sublime you can heat them away with a gas torch. When no more of the pyridine comes off stop heating the mixture. Then redistill the pyridine. If you want to eliminate as much of the niacin from the pyridine you can at first reflux the niacin copper mixture for an hour and then distill the pyridine off.
Heating the niacin crystals with torch
After completion copper chromite residues are left in the RBF
Distillation of the pyridine