By hvhipot 
The trace moisture analyzer under HV Hipot Electric Co., Ltd. power can help many power workers conduct various power tests more conveniently.
Karl Fischer titration (KF) is a technique for determining moisture content. It is based on the process of iodine reacting with water. The KF method is one of the few techniques for measuring water content that is not affected by other volatile compounds. Using HV Hipot Electric Co., Ltd. KF titration device, it is possible to determine free water and bound water, such as surface water on crystals or water contained within them. This method is suitable for a wide concentration range of 5 ppm to 100% and can provide reproducible and accurate results. Our equipment can effectively test various types of solid or liquid samples. The sample size can vary, typically between 0.5-5 grams, depending on the water content in the sample. There are two methods for performing Karl Fischer titration tests, namely volume and coulomb.
Volume titration is used for moisture content above the range of 1-2%. In this method, the sample is directly injected into an airtight titration cell containing a solvent and dissolved before titration begins. By using an automatic burette, adding reagents and reacting with water to return conductivity to the starting point. Calculate the water/water content in the sample based on the required amount of reagent to achieve this point. Its moisture content ranges from 100 parts per million to 100%.
For Coulombic titration, combine the reagent and solvent in the titration cell. When the sample is introduced into the titration cup and dissolved, the reagent is released through induced current. Moisture is determined by the amount of current required to consume water. The advantage of Coulomb KF method is that it can accurately measure small amounts of moisture. Our instrument has a sensitivity as low as 0.1 micrograms (μ g) of water. This method is typically used for samples with a moisture content below 1% or for samples with a moisture content below 200 micrograms.
Adding a dedicated oven can analyze the moisture in solid samples or analyze unique liquid samples through moisture evaporation. For samples that work by direct injection, they need to be dissolved in a solvent compatible with KF reagents. Substances that release water slowly or at high temperatures (such as plastics or inorganic salts) are not suitable for direct Karl Fischer titration. For these samples, we can use oven accessories to determine the moisture content.
Weigh the sample into its own sample bottle and seal it to minimize contamination and carryover effects. The use of PTFE covered spacers can prevent the surrounding air from absorbing any moisture. Place the small bottle in the oven chamber and heat it, transfer the released water to the titration cup with carrier gas, and then determine it by KF titration. Depending on the water content of the sample, subsequent KF water determination can be performed in volumetric or trace amounts. Due to the fact that only water enters the KF pool and the sample itself does not come into contact with the KF reagent, unwanted side reactions and matrix effects are eliminated.
These methods are widely used in transformer oil monitoring, crude oil and lubricant analysis, polymer analysis, as well as many application fields in solvent, pharmaceutical, and chemical industries.