Oxidation: When glycerol is oxidised with H₂O₂ in slight alkaline solution in the presence of iron salt, a mixture of trioses, glyceric aldehyde, and dihydroxy acetone is formed.

Acrolein formation: When glycerol is heated either alone or in the presence of dehydrating agent like KHSO₄, a substance called acrolein, which is an unsaturated aldehyde, is obtained.