Microfluidic filtration

ENVR 90

Ikenna S. Ngene, i.s.ngene@utwente.nl1, Rob G. H. Lammertink, r.g.h.lammertink@utwente.nl2, Matthias Wessling, M.Wessling@utwente.nl2, and Walter G. van der Meer, walter.vandermeer@vitens.nl1. (1) Membrane Process Technology, University of Twente, P.O. Box 217, 7500AE, Enschede, Netherlands, (2) Membrane Technology Group, University of Twente, P.O. Box 217, 7500 AE Enschede, Netherlands
This study investigates the flow of liquids in, along and through the porous walls of microfluidic chips using direct observation through the membrane (DOTM). It monitors the development of fouling in scaled down membrane filtration systems. Microfiltration membranes with channel structures are prepared using phase separation micro molding (PSµM). The channels are separated by a porous structure which mimics the filtration membrane. The flow pattern of liquids along the walls of the channel is traced using polystyrene latex particles of size 3-10 µm. Permeation of the liquid is observed through the feed channel wall into the adjacent channel with a deposition of the particles on the surface of the feed membrane wall. Particle deposition occurs on a surface which is observed in cross-section. This ensures that with cake build up, subsequent layers can be observed and quantified. Increasing cake thickness has been observed along the feed flow direction.