Determination of water content in ketones with Karl Fischer reagents can be tricky. Side reactions from the alcohol found in most KF reagents can lead to incorrect results – even more so when performing coulometric Karl Fischer titration. Alcohol-free KF reagents allow the water content to be determined in ketones via a different pathway and stoichiometric ratio with the Bunsen reaction. Honeywell’s Hydranal™ NEXTGEN FA reagents are alcohol free and contain a stabilizer to suppress the Bunsen reaction. The end result is a quick and reliable 1:1 reaction of water and iodine with fewer side reactions than other existing KF reagents for ketones on the market.
The reaction of ketones with alcohol in conventional KF reagents forms ketals which ultimately release water. The extra water falsifies the titration results and can be especially problematic for coulometric Karl Fischer titration.
Hydranal™ NEXTGEN FA reagents from Honeywell contain no alcohol component and suppress side reactions better than other Karl Fischer reagents during moisture analysis in ketones. As these alcohol-free KF reagents are sensitive to light, tests were performed to gauge the effectiveness of various experimental setups against the light-induced release of iodine.
Other experiments were carried out to test the ability of alcohol-free Hydranal™ KF reagents from Honeywell to help measure water content in a range of samples. Aside from two different water standards, several ketones (including acetone, butanone, 1-methyl-2-pyrrolidone, 2,4-dimethyl-3-pentanone, and acetylacetone) were used. Water content determination in various ketones is shown to be fast and reproducible with the tested Hydranal™ NEXTGEN FA reagents.
Learn more about water content determination in ketones with coulometric KF titration and alcohol-free reagents here.
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