Ascorbic acid is the safest and cheapest way to neutralize chlorine and chloramine.
One gram of ascorbic acid will neutralize 1 milligram per liter of chlorine per 100 gallons of water. The reaction is very fast. The chemical reaction (Tikkanen and others 2001) of ascorbic acid with chlorine is shown below:
C5H5O5CH2OH + HOCL → C5H3O5CH2OH + HCl + H2O
Ascorbic acid + Hypochlorous acid → Dehydroascorbic acid + Hydrochloric acid + water
Approximately 2.5 parts of ascorbic acid are required for neutralizing 1 part chlorine.
