Magnetschwebewaage - LCVT

Die Zukunft muss heute gedacht werden Prof. Dr. Andreas Jess, Lehrstuhl für chemische Verfahrenstechnik an der Universität Bayreuth, über die Zukunftsfähigkeit seiner Wissenschaft, Ethos und die Frage, wie viel Erde braucht der Mensch.
Gefragt sind Studenten und Absolventen, welche sich im Rahmen einer Studien-, Teamprojekt-, Bachelor-, Master- , Diplom- oder Doktorarbeit auch im Rahmen einer Industriekooperation mit verschiedensten Fragestellungen der chemischen Verfahrenstechnik beschäftigen möchten.
Zusammen mit Prof. Peter Wasserscheid vom Lehrstuhl für Chemische Reaktionstechnik der Universität Erlangen/Nürnberg veröffentliche Prof. Andreas Jess im Februar 2013 das Fachbuch mit dem Titel "Chemical Technology - An Integrated Textbook" .

Magnetic suspension balances (MSB)

Magnetic suspension balances (MSB) allow obtaining extremely precise measurements of mass changes which act on samples under defined environments (pressure, temperature, aggressive atmospheres etc.). These measurements enable to determine transport quantities and state quantities quickly and accurately, (sorption, diffusion, surface, tension, density).

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Fig. 1: MSB at Department of Chemical Engineering

In this method, the measuring force is transmitted contactless via magnetic coupling from the measuring chamber to a microbalance, which is located outside the chamber under ambient atmospheric conditions. The suspension magnet, which is used for transmitting the force, consists of a permanent magnet inside of the measuring chamber; a sensor core and an electromagnet outside the chamber attached to the microbalance (see Fig.2). 
The atmospheric disjunction of microbalance and sample in the MSB allows the measurement of weight changes of samples under severe conditions (T< 250 °C, p < 400 bar). Because of the very high precision (- 0.01 mg) of the microbalance, this technique is particularly suitable to study the sorption of gases in liquids or solids. Therefore an interesting field for application of a MSB is the determination of sorption and diffusion properties of gases and gas components in ionic liquids (ILs) or in polymers.

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Fig. 2: Schematic depiction of a MSB

Selected publications:

Dreisbach, F.; Losch, H. W.: Magnetic suspension balance for simultaneous measurement of a sample and the density of the measuring fluid. of Thermal Analysis and Calorimetry (2000), 62(2), 515-521.

Dreisbach, Frieder; Seif A. H., Reza; Loesch, Hans Wilhelm: Measuring techniques for gas-phase adsorption equilibria. Chemie Ingenieur Technik (2002), 74(10), 1353-1366 (in german).

Kern, C.; Jess, A.; Altstaedt, V.; Langenfelder, D.; Woellecke, F.: Measurement of solubility and mass transfer of CO2 in polymeric materials using a magnetic suspension weighing device. Chemie Ingenieur Technik (2004), 76(9), 1352 (in german).

Kern, C.; Jess, A.; Korth, W.: Use of a magnetic suspension weighing device for determination of gas solubility and mass transfer in ionic liquids. Chemie Ingenieur Technik (2004), 76(9), 1351-1352 (in german).

Kern, C.; Korth, W., Jess, A.: Determination of Gas Sorption and Mass Transfer in Ionic Liquids by Means of a Magnetic Suspension Balance. 1st International Congress on Ionic Liquids (COIL), 19.-22.6. 2005, Salzburg /Austria.

Contact: C. Kern