Posted in Products - Ionic Liquids
Solvents for Karl-Fischer-Titration
The determination of water in a broad variety of different samples is of great importance in many areas of industrial analytics such as food industry, pharmaceuticals and fine chemicals. The most common method for the quantitative determination of the water content of a sample is either volumetric or coulometric titration according to the Karl-Fischer procedure. The equipment for the titration process includes an automatic titrator, special reagents for the titration and a water free solvent that is able to dissolve many different substances completely.
The limiting factor in many cases in pharmaceutical and food industry is the poor solubility of the analyte in common solvents. For this reason huge efforts are undertaken in sample preparation to determine the water content by indirect methods. IOLITEC has developed a method that takes advantage of the manifold solvent properties of ionic liquids in matters of Karl-Fischer titration, especially to enable the determination of water content of materials that are almost insoluble in conventional solvents. Even though the classic solvents are applicable for a wide range of materials there are still problems in the analysis of food, pharmaceutical or polymer samples which can only be dissolved by introducing new Karl-Fischer solvents.
For a number of examples (e.g. cheese, nuts or some (bio-)polymers) IOLITEC has demonstrated that these materials can be dissolved completely in our innovative Karl-Fischer solvents. As a consequence, it is possible to determine the water content of these products directly without expensive sample preparation procedures.
Ionic Liquids for Heat Transfer
The use of ionic liquids as media for heat transfer was first described by Rogers et al.
Even though the initially published thermal stabilities of >400°C can not be achieved with most ionic liquids, materials with long term stabilities of up to 250°C have been identified.
Typical ionic liquids that have been studied by IOLITEC for this application consist of ammonium-, phosphonium-, imidazolium or pyrrolidinium-cations in combination with a variety of anions such as sulfate derivatives, fluorinated anions, phosphate derivatives or sulfonates.
Many ionic liquids from these combinations show high heat capacities, high heat storage densities and good thermal stabilities. In addition most of these compounds show low almost negligible vapor pressure which is a huge advantage over conventional heat transfer media.
IOLITEC has currently identified the following areas of applications
- · Solar thermal roof top devices
- · Special thermal oils for high stress applications
IOLITEC investigated the use of ionic liquids in solar thermal roof top devices in the feasibility study “IOFLAW” which was financed by the Deutschen Bundesstiftung Umwelt e.V. (DBU)
Further information on this topic can be found here http://www.dbu.de/123artikel25625_.html (only available in German).
If you are interested in additional information, please contact us.
Ionic Liquids – Lubricants, Lubricant Additives and hydraulic fluids with unique properties
Ionic liquids possess a couple of properties that make them interesting functional fluids in a variety of applications. Among these properties are::
- low vapor pressure
- inflammability
- interesting rheological and tribological properties
- wide thermal stability
- good chemical stability
- high surface tension
In ionic liquids the phenomenon of cavitation is less distinctive than in other materials due to their low vapor pressures. In addition some ionic liquids can act as corrosion inhibitors. These properties lead to many new areas of application in lubrication or hydraulics and have been investigated and published by different groups.
Literatur:
Tribological behavior of Dy-sialon ceramics sliding against Si3N4 under lubrication of fluorine-containing oils.
C. Ye, W. Liu, Y. Chen, Z. Ou, Wear 2002, 253, 579-584.
Room-temperature ionic liquids: a novel versatile lubricant.
C. Ye, W. Liu, Y. Chen, L. Yu., Chem. Comm. 2001, 2244-2245.
Friction and wear behaviors of ionic liquid of alkylimidazolium hexafluorophosphates as lubricants for steel/steel contact.
H. Wang, Q. Lu, C. Ye, Q. Liu, Z. Cui, Wear 2004, 256, 44-48.
Room temperature ionic liquid 1-ethyl-3-methyl-imidazolium bis(trifluoromethyl-sulfonyl)imide as lubricant for steel-steel contact.
Q. Lu, H. Wang, C. Ye, W. Liu, Q. Xue, Tribology International 2004, 37, 547-552.
IOLITEC hat einige Materialien hinsichtlich einiger Eigenschaften bereits untersucht. Sollten Sie Interesse an diesen Materialien haben, dann erhalten Sie uns selbstverständlich weiterführende Informationen.
