KARL FISCHER, AQUAGENT® REAGENTS AND STANDARDS

Karl Fischer titration is the globally accepted method for determining water content since the early 20th century. It is based on the Bunsen reaction, a two-phase reaction with a stoichiometric relationship between the consumed I2 and the amount of water in the sample. The initial KF reagents contained pyridine in their formulation, believed to be essential for the reaction. Subsequent experiments demonstrated that pyridine merely acted as a buffering substance and could be substituted with other basic compounds capable of performing the same function but with lower toxicity. For this reason, Karl Fischer reagents without pyridine, such as our Aquagent®, contain imidazole instead. Imidazole is a non-toxic base with good buffering capacity, allowing for the rapid attainment of stable endpoints in the titration.