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Chemistry Forums for Students => Analytical Chemistry Forum => Topic started by: wintermute on November 27, 2009, 04:18:20 AM

Title: Karl Fisher titration of compound insoluble in ROH, ROH/DMSO or ROH/formamide mx
Post by: wintermute on November 27, 2009, 04:18:20 AM
Hello everybody,

May I ask anybody skilled in Karl Fisher titration how to determine water content (presumably 0.1 - 3%) in organic compound, which is insoluble either in methanol (ethanol) or in DMSO/methanol mixture. Moreover, addition of formamide failed in solubilizing the compound in methanol.

Is there commercially available alternative to alcohol based titration systems?

Thanks in advance for any comment.

wintermute
Title: Re: Karl Fisher titration of compound insoluble in ROH, ROH/DMSO or ROH/formamide mx
Post by: marquis on November 28, 2009, 01:57:11 PM
I suggest discussing your problem with the technical representative from one of the Karl Fisher (KF) companies.

One other approach is to add the organics directly to the KF solution.  I've done this with fine organic powders.  You want to make sure the solution is magnetically stirred, to maximize contact with the solution.  And the titration is slower.  Not the best approach, but maybe as a last resort.