Home > DoHippies

Daniel Varga

Varga Dániel, graduated at the Budapest University of Technology and Economics with a Master Degree of Chemical Engineering. During my studies I was mainly focused on analytical chemistry but as a student researcher the more application oriented and preparative work in process engineering took my interest. I have been working with supercritical carbon dioxide since three years. During my studies I carried out extraction reactions, recently I am dealing with supercritical impregnation of polymers under the supervision of Prof. Thomas Gamse in Graz, Austria. In my spare time I usually do sports like jogging, climbing and mountain hiking or going out with my friends.

Topic

Supercritical fluid impregnation is an environmental friendly and effective method for creating new materials. By the use of supercritical media, usage of organic solvent can be reduced or totally excluded, no solvent residues remain in the product and no drying step is necessary at the end of the process. Most recent examples for sc. impregnation are dying of cotton fibers, wood impregnation with biocides, introducing metallic complexes into aerogels as catalysts and realizing polymerization reactions in situ in supercritical media; performing all these in one single step. During the process, the solid matrix and the solute are placed in a high pressured vessel which is sealed and then pressurized with carbon dioxide. The solute dissolves in the supercritical fluid accordingly to its solubility. CO2-dissolved solute penetrates then in the matrix governed by diffusion. Mostly temperature, pressure, concentration of the solute, impregnation time, solubility and the properties of the solid matrix determines the efficiency. During a controlled depressurization, carbon dioxide leaves the system while solute is left behind trapped in the matrix. Depressurization rate is crucial here. Within my topic I am mainly focused on impregnation of different polymer pellets with fibers to create fibers reinforced materials.



Coordinator's office:
Dr. S. Kareth
IC 3/65
Chair for Process Technology
Faculty Mechanical Engineering
Ruhr-University Bochum
D-44780 Bochum, Germany
e-mail: Kareth@vtp.rub.de
www.vtp.rub.de