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Coulometric microdetermination of water
1Department of Analytical Chemistry, Chemical Center, University of Lund, S-220 07 Lund 7, Sweden.
Talanta
|May 1, 1971
Summary
A new electroanalytical method precisely determines small water amounts using controlled potential coulometry and Karl Fischer reagent. This technique offers accurate water content analysis in just 3-12 minutes.
Area of Science:
- Analytical Chemistry
- Electrochemistry
Background:
- Accurate determination of trace water is crucial in various scientific and industrial applications.
- Traditional Karl Fischer titration methods can be time-consuming and require manual operation.
Purpose of the Study:
- To develop a precise and efficient electroanalytical method for quantifying small amounts of water.
- To optimize Karl Fischer reagent composition and electrolysis cell design for improved water determination.
Main Methods:
- Controlled potential coulometry was employed for iodine generation and consumption.
- An electronic integrator was used to measure coulombs consumed during the cell reaction.
- A specialized glass and Teflon electrolysis cell was designed and utilized.
Main Results:
- The method accurately determined water samples containing 0.1-2 mg of water with an accuracy of +/- 0.15%.
- Analysis times ranged from 3 to 12 minutes, demonstrating significant efficiency.
- Various Karl Fischer reagent compositions were evaluated to establish optimal conditions.
Conclusions:
- The devised electroanalytical method provides a rapid and accurate means for determining trace water content.
- The optimized Karl Fischer reagent and specialized electrolysis cell contribute to the method's high performance.
- This coulometric approach offers a valuable alternative for precise water analysis.
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