We have located links that may give you full text access.
Progress in Karl Fischer coulometry using diaphragm-free cells.
Analytical Chemistry 2001 November 16
Different designs of a semiopen, drainable cathode compartment of a medium-sized coulometric Karl Fischer (KF) cell for the determination of water in the range 0.1-500 microg were evaluated. The main criterion for the design was to keep the resistance between the anolyte and catholyte low enough to permit the generation of currents larger than 20 mA (for an output voltage of 28 V). It was found that a good compromise between the size of this current and a minimal influence from diffusing/migrating oxidizable reduction products from the catholyte was achieved by means of an interface having a channel length and diameter of 8 and 2.1 mm, respectively (catholyte volume, approximately 1 mL). To show the general applicability of the concept, the following different types of coulometric reagents suitable for nonpolar and polar samples, as well as for samples containing active carbonyl compounds, were investigated: Hydranal Coulomat A, AD, AK, AG-H (modified with chloroform, Merck), and two homemade methanolic reagents modified with 40% (v/v) chloroform and 50% (v/v) formamide, respectively. Except for Hydranal Coulomat A, the mean value of five consecutive titrations of 50 microg water did not deviate by more than 0.2% from the expected value for all reagents. Draining after every titration was sufficient to obtain accurate results, even for Coulomat A which, when used in the commercial diaphragm-free system of Metrohm, gave values which were about 10% too high. As compared to earlier reported results for diaphragm-free coulometry, the descibed modified cell represents a significant improvement, mainly because of the high accuracy achieved for all types of reagents.
Full text links
Related Resources
Trending Papers
Obesity pharmacotherapy in older adults: a narrative review of evidence.International Journal of Obesity 2024 May 7
SGLT2 Inhibitors in Kidney Diseases-A Narrative Review.International Journal of Molecular Sciences 2024 May 2
Get seemless 1-tap access through your institution/university
For the best experience, use the Read mobile app
All material on this website is protected by copyright, Copyright © 1994-2024 by WebMD LLC.
This website also contains material copyrighted by 3rd parties.
By using this service, you agree to our terms of use and privacy policy.
Your Privacy Choices
You can now claim free CME credits for this literature searchClaim now
Get seemless 1-tap access through your institution/university
For the best experience, use the Read mobile app