Comparison of volumetric and coulometric titration cells.
In the volumetric technique, which is used to determine higher water contents generally at levels above 5%, the iodine is introduced via a burette or similar dosing system. For lower water content detection, down to ppm levels, the coulometric technique produces the iodine
in-situ by electrolysis. Coulometry improves the Karl Fischer technique by removing the need for reagent calibration and
provides an absolute result in micrograms of water.
Low reagent usage: multiple samples can be analysed with a single charge of reagent which means less waste and less handling of chemicals, good news for Health and Safety
Karl Fischer KF Reagent
Karl Fischer KF Reagent A is a general coulometric KF anolyte for use with generator electrodes which incorporate a frit or diaphragm to separate the anode and cathode chambers. Used in conjunction with Reagent C this formulation is supplied in a pack of 8 x 100ml bottles, 8 x 5ml cathode vials, all conveniently located in a single carton.
To conform to ASTM, API, EI, ISO (plus others) methodology for water content determination of oil and petroleum products, the anode regent must be modified with xylene to improve sample solubility and miscibility. Karl Fischer KF Reagent is pre-mixed with xylene, and other solubilizers to eliminate side reactions, so that the operator does not have to store or mix chemicals.
Karl Fischer KF Reagents combine speed and accuracy
VOLUMETRIC COULOMETR K.F. Titration Cell Differences
• Single shot bottles
• Safer to use
• Safer to store
• Low cost
• Faster precondition
• Reduced downtime
• Improved sample miscibility / solubility
• For use with all coulometers