Surface modification of microfiltration membranes to decrease biofouling

ENVR 91

Ramamoorthy Malaisamy, malaisamy@gmail.com1, David Berry2, Tanna B. Borrell2, Diane Holder2, Lutgarde Raskin, raskin@umich.edu2, and Kimberly L. Jones, kljones@howard.edu1. (1) Department of Civil Engineering, Howard University, 2300 Sixth St., NW, Washington, DC 20059, (2) Department of Civil and Environmental Engineering, University of Michigan, 1351 Beal Ave, 17 EWRE Bldg, Ann Arbor, MI 48109-2125
Biofouling is a significant problem during microfiltration (MF) of biologically active feeds. Disinfectants are often used to discourage biological growth on membrane surfaces; however, many membranes are oxidant sensitive, so an alternative approach is desirable. We are exploiting the bactericidal potential of quaternary ammonium acrylic polymers by grafting them onto MF membrane surfaces. Specifically, [2-(acryloyloxy)ethyl]trimethylammonium chloride (AETMA) was graft-polymerized onto polyethersulfone membrane surfaces using UV initiation. Modification was quantified by the degree of grafting, streaming potential and FTIR spectroscopy. Permeability decreased, however, the Escherichia coli suspension flux decline was only ~30% and flux recovery after hydraulic cleaning was almost 100% for the modified membranes, compared to 40% for the unmodified membranes. Fluorescence microscopic imaging of AETMA grafted membranes indicated that the E. coli cell membranes were damaged, while no such evidence was noticed on unmodified membranes. Thus the modification improved flux recovery and antimicrobial properties of the membranes.
 

Membrane Technology for Water Treatment and Reuse
1:30 PM-5:10 PM, Monday, April 7, 2008 Morial Convention Center -- Rm. 237, Oral

Division of Environmental Chemistry

The 235th ACS National Meeting, New Orleans, LA, April 6-10, 2008