Photo-active porous polymer composite fibers and membranes for water treatment

J. Markovski, R. Mathews, V.V.K. Pentapati, G. Athanasaki, B. Azeredo, K. Hristovski
Arizona State University,
United States

Keywords: nano-enabling, titanium dioxide, UV transparency, photocatalysis, scalability

Summary:

Photocatalysis has emerged as a promising transformative technology capable of reducing some priority contaminants to innocuous product. No photocatalytic technologies are currently commercially available mainly due to problems associated with the cost-effective application of the nano-sized catalyst under realistic conditions. To address this scalability gap, goal of this work is to fabricate polymer composite fibers and membranes that meet UV transparency, photocatalytic functionality and controlled porosity required for photocatalytic treatment of water under fast continuous water flow. For that purpose, UV stable and un-expensive polymethyl methacrylate is nano-enabled with titanium dioxide and composite porosity is controlled by polyethylene glycol as a porogen and low-temperature boiling solvents as co-porogen agents. Thin-films polymer composite have been developed and their morphology, permeability and optical properties are under investigation. Preliminary results suggest that polymethyl methacrylate fibers with 100 μm diameter and membranes with 50 μm thickness can be fabricated by micromachined die inserts for extrusion and drop casting, respectively. The developed media might be manufactured at scale and applied in UV LED-based modular POU treatment systems where coupling photo-redox processes with fabricated fibers and membranes have potential to improve selectivity and quantum yield for removal of priority contaminants while enabling scaling and fouling control beyond the membrane’s surface.