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07:49
On-line Analysis of Nitrogen Containing Compounds in Complex Hydrocarbon Matrixes
Published on: August 5, 2016
Urea as the basic component in pyridine-free Karl Fischer reagent
1Department of Chemical Technology, Technical University Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands.
Talanta
|July 1, 1984
Summary
A novel methanol-based solvent containing urea, sulfur dioxide, and sodium salicylate offers advantages for Karl Fischer titration, particularly for amine samples.
Area of Science:
- Analytical Chemistry
- Titration Methods
Background:
- Karl Fischer titration is a standard method for water determination.
- Existing reagents may have limitations, especially with certain sample types like amines.
Purpose of the Study:
- To introduce and evaluate a new solvent system for Karl Fischer titration.
- To assess the suitability of this new solvent for analyzing amine-containing samples.
Main Methods:
- A methanol-based solvent comprising urea, sulfur dioxide, and sodium salicylate was prepared.
- This solvent was used as the medium for Karl Fischer titration with a separate iodine titrant.
- Performance was compared against commercial Karl Fischer reagents.
Main Results:
- The proposed solvent demonstrated effective performance in Karl Fischer titrations.
- Distinct advantages were observed when titrating samples containing amines.
Conclusions:
- The urea, sulfur dioxide, and sodium salicylate in methanol solvent is a viable alternative for Karl Fischer titration.
- This method shows particular promise for the accurate water content analysis of amine samples.
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