1. Research Institute on Membrane Technology
2. ITM-CNR
3. I-87030 Rende
4. Italy
5. On leave from Gdansk University of Technology
6. Department of Chemical Technology ul., G. Narutowicza 11/1280-233 Gdańsk
7. Poland
8. Department of Physical and Chemical Sciences
9. University of L'Aquila
10. 67100 L'Aquila
11. Department of Environmental and Chemical Engineering