NSF Nanoscale Science and Engineering Grantees Conference, Dec 4-6, 2006 Grant # : 0506828 Self-cleaning Ceramic Membranes for the Removal of Natural and Synthetic Nanomaterials from Drinking Water Using Hybrid Ozonation-Nanofiltration NSF NIRT Grant 0506828 Jeonghwan Kim 1,2 , Alla L. Alpatova 1 , Lindsay M. Wright 2 , Thomas L. Deits 3 Simon H. R. Davies 1 , Melissa J. Baumann 2 , Volodymyr V. Tarabara 1 , Susan J. Masten 1,4 1 Department of Civil and Environmental Engineering, Michigan State University, East Lansing, MI 48824, USA; 2 Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI 48824, USA; 3 Science Department, Lansing Community College, Lansing, MI 48823, USA; 4 Department of Civil Engineering, McMaster University, Hamilton, ON L8S4L7, Canada Motivation and Objectives The trademark of the science of the 21 st century is environmental awareness that dictates a proactive approach to ensuring that novel technologies fit well within the framework of ecologically sustainable development. The recent explosion in nanotechnology research has resulted in the synthesis of a range of novel materials often possessing unique properties that have yet to be fully understood. As environmental scientists, we are asking and looking for answers to the following questions: What will happen when nanomaterials enter our environment? What are their transport pathways and fate in the environment? Should they and how can they be removed from the environment? Which treatment systems are most effective to remove nanomaterials from air and water? The aim of this project is to build a base of fundamental knowledge pertaining to the hybrid ozonation filtration process and to apply this new knowledge to develop an effective water treatment system targeting the removal of nanoparticles from water. Novel high performance membranes, an integral component of the O 3 - NF system, featuring reduced permeability and improved catalytic properties are also being developed [1]. Research Activities and Findings Combined effect of ozonation and hydrodynamic conditions on the permeate flux in the hybrid ozonation-filtration system. Bench-scale, hybrid ozonation/high-pressure membrane filtration apparatus was installed to investigate the effect of ozonation on membrane fouling at Michigan State University. A key feature of the installation is the design and operation of relatively high- pressure membrane filtration system combined with ozonation process. The effects of ozone concentration and hydrodynamic conditions on the permeate flux in a hybrid ozonation-ceramic membrane filtration system treating prefiltered (0.45 µm) natural water (Lake Lansing, MI) were investigated. In one set of experiments, continuous ozonation was initiated after 50% of flux decline was observed. The extent of the permeate flux recovery upon the application of ozone was found to depend on the ozone dosage, transmembrane pressure, and crossflow velocity. Higher recoveries were achieved at greater ozone concentrations, lower transmembrane pressures and higher crossflow velocities (Figures 1-3) [3]. When ozone was continuously applied during the entire fouling experiment, higher permeate fluxes were observed. The difference in the behavior observed in the two sets of experiments suggest that the permeate flux recovery is affected by the accessibility of the oxidants generated at the membrane surface to the materials fouling the surface.