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Analytical / Chromatography > Analytical Standards  > Application Area & Technique > Biofuels > Water Determination
Biofuels

Water Determination

Karl Fischer Titration - HYDRANAL® Reagents for the Determination of Water in Biodiesel 

The presence of water in biodiesel poses problems for a number of reasons. Some of the water is residual from processing while some comes from condensation in the storage tanks. Water content can be determined accurately and reproducibly by Karl Fischer Titration (volumetric, coulometric, and KF-oven methods) using reliable, superior, and proven HYDRANAL reagents (EN 14214).

Volumetric Titration
Coulometric Titration
Karl Fischer Oven Method

biodiesel karl fischer

Volumetric Titration back to top

Biodiesel contains components of different chain lengths. Therefore, a solubilizer is often required to dissolve or disperse it in order to extract the moisture. A number of HYDRANAL media are available for effective dispersion of biodiesel. HYDRANAL-Composite 2 is used as the titration agent.

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Coulometric Titration back to top

The coulometric procedure is more sensitive than the volumetric titration method. Determination of water is carried out in a coulometric cell (with or without diaphragm). The precision of the coulometric cell and the sample manipulation can be tested by means of HYDRANAL Water Standard 0.10.


Karl Fischer Oven Method back to top

This method is suitable for samples that release water at a higher temperature. In this method, HYDRANAL-Coulomat CG is placed in the cathode chamber and HYDRANAL Coulomat AG Oven is added to the anode chamber of a coulometric cell with diaphragm. A cell without a diaphragm requires only the Coulomat AG Oven. HYDRANAL Coulomat AG-H or HYDRANAL Coulomat AD may be used as a replacement for HYDRANAL Coulomat AG Oven. HYDRANAL Molecular Sieve 0.3 mm is a drying medium for the carrier gas.

HYDRANAL Coulometric Titration

Karl Fischer Oven products

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