Karl Fischer titration is a classic titration method in analytical
chemistry that uses coulometric or volumetric titration to determine trace
amounts of water in a sample. It was invented in 1935 by the German chemist
Karl Fischer.
Advantage of
analysis
The popularity of the Karl Fischer titration is due in large part to
several practical advantages that it holds over other methods of moisture
determination, including:
01. High accuracy and precision
02. Selectivity for water
03. Small sample quantities required
04. Easy sample preparation
05. Short analysis duration
06. Nearly unlimited measuring range (1ppm to 100%)
07. Suitability for analyzing:
Ø Solids
Ø Liquids
Ø Gases
08. Independence of presence of other volatiles
09. Suitability for automation
10. In contrast, loss on drying will detect the loss of
any volatile substance.
The major disadvantage is that the water has to be accessible and easily
brought into methanol solution. Many common substances, especially foods such
as chocolate, release water slowly and with difficulty, and require additional
efforts to reliably bring the total water content into contact with the Karl
Fischer reagents.
No comments:
Post a Comment