Karl Fischer moisture titratorUse the permanent stop method to determine the endpoint. When both I2 and I - are present in the solution, the above reaction occurs on two electrodes, where I2 is reduced on one electrode and I - is oxidized on the other electrode, resulting in a current passing through the solution. If there is only I - and no I2 in the solution, then there is no current passing through the solution. When there is a trace amount of Karl Fischer reagent present in the solution at the endpoint of titration, both I - and I2 are present simultaneously. At this time, the solution conducts electricity, and the ammeter pointer deflects, indicating that the endpoint has been reached. Calculate the moisture content based on the amount of iodine consumed in the titration reaction.
Application fields:
Liquid:
Chemical industry: products suitable for Karl Fischer method determination, such as alcohols, ethers, acids, benzenes, phenols, organic solvents, etc.
Petroleum and power industry: insulating oil, transformer oil and other oil products.
Pharmaceutical industry: pharmaceutical raw materials, etc.
Pesticide industry: emulsifiers, etc.
Other industries: lithium battery electrolytes, etc.
Solid: various inorganic salts, citric acid and other solid substances with good solubility
Gas: Nitrogen SF6、 Natural gas, liquefied gas, fluorocarbons, butadiene and other gases
The following industries require the use of card type heating furnaces:
Insoluble solids: lithium battery industry, plastic industry, medical industry, ceramic powder, metal powder, etc
Other insoluble solids: insoluble solids, easily contaminated and cross contaminated samples (lubricating oils, aldehyde ketone samples), samples that easily react with Karl Fischer reagent, samples with slow water release
Storage method of Karl Fischer reagent:
Sealing and light avoidance:
Brown bottles must be sealed and stored to avoid exposure to light and air, and to prevent the reagents from absorbing moisture or decomposing.
Immediately seal the bottle cap after use to reduce exposure time.
Storage environment:
Temperature control: It is recommended to store in refrigeration (4 ℃), and warm it back to room temperature 24 hours before use.
Drying measures: Molecular sieves or color changing silica gel desiccants should be placed inside the reagent bottle. If the silica gel changes color (such as blue → pink), it should be replaced or activated in a timely manner (dried at 120 ℃ for 4 hours).
Validity period and inspection:
When the reagent fails, there may be no significant appearance changes, but it can lead to detection errors exceeding 20 times.
Check the status of the reagents every month, and replace them immediately if there is turbidity, precipitation, or yellowing in color.