• Mendes, Am
• Magalhaes, Fd
• Costa, Cav

Abstract

Research on membrane science and technology has undergone a tremendous increase along the last 20 years. Nowadays, about 6% and 10%, respectively, of the total amount of papers published in two Chemical Engineering reference journals, Chemical Engineering Science and AIChE Journal, are related to membrane research. On the other hand, the international journal exclusively dedicated to this subject, the Journal of Membrane Science, is publishing about eight times more papers now than twenty years ago. The largest industrial applications of membranes in the past were for military purposes (ceramic membranes for the enrichment of uranium 235), hemodialysis and desalinization. Soon technologies such as micro-, ultra-, nano- and hyperfiltration (also known as reverse osmosis) were introduced in waste-water treatment and food industry. Membranes started also being used for gas separation, namely for removing VOC's from air streams. The research on more conventional membrane technologies, such as the filtrations, is now more focused on the optimization of membrane modules and membrane life time and cost. Nevertheless, a rising research activity can be found in the area of material development, since it has been found that ultramicroporous membranes such as carbon molecular sieve, zeolite and nanocomposite glassy polymeric membranes show far higher permeabilities and selectivities than the conventional polymeric membranes. New areas of application of membrane related technologies are also being explored, namely in promising fields such as pharmaceutical and chemical specialties. Several research laboratories, both in academia and industry, now have major work topics like drug delivery systems (mainly nanocapsules), pigment container systems (mainly microcapsules), gas concentration sensors, polymeric, ceramic or metallic catalytic membranes (used simultaneously as catalyst support and separation medium), membranes in nanotechnology or proton conductive membranes for fuel cells. The present lecture alms to give an overview on the rising trends in this area, providing an interested reader with the basic information on the following membrane related research topics: a) nano- and microcapsules delivery systems; b) intelligent membranes; c) membrane-based sensors; d) membranes in fuel cells; e) catalytic membranes reactors and f) nanoporous membranes for gas separations.

Topics

• nanocomposite
• impedance spectroscopy
• Carbon
• ceramic
• Uranium