Abstract: Heterogeneous catalysis for water decontamination through advanced oxidation processes has been widely investigated for decades. There is voluminous literature on lab-scale investigations of heterogeneous photocatalysis, sulfate-radical based oxidation processes, Fenton and Fenton-like processes, and catalytic ozonation for degradation of recalcitrant organic pollutants in water. Despite all the efforts to improve the catalysts, there are still very limited applications of heterogeneous catalytic oxidation processes in the real-world water treatment. This presentation provides an overview of heterogeneous catalysis for water decontamination, and addresses the several fundamental and practical issues that have hindered their adoption for real water treatment by the industry. One possible solution to overcome the challenges will be addressed. This involves coupling membrane separation process based on ceramic membrane and catalytic oxidation with nanocatalysts. In this hybrid system, the porous ceramic membrane serves as nanocatalyst support and the nanocatalysts-decorated micropores create a contiguous microreactor environment that can intensify the degradation of recalcitrant micropollutants leading to their mineralization within the ceramic membrane. Through a delicate technique of layer-by-layer depositions to form a hierarchically porous filtration layer, the water matrix constituents that can hinder the catalytic reaction process, including bulk organics and colloidal particles can be separated out by the catalytic membrane. The synergistic coupling of the two processes is demonstrated in a laboratory pilot-scale experiment.

Biography: Professor Lim obtained his PhD degree in Environmental Engineering from the Nanyang Technological University, Singapore, in 1998. He joined NTU in 2000 as Assistant Professor and is now a professor of environmental engineering. His fields of research include nanomaterials for environmental decontamination, environmental catalysis, advanced water treatment and waste-to-energy/materials. He has published over 200 journal papers and book chapters, with Web of Science citation count of 11,000. He is one of the founding editors of the Journal of Environmental Chemical Engineering, Elsevier. He has led various research projects with a total funding of over US$6 millions. Some of his inventions have resulted in 10 filed intellectual properties including PCT patents. Besides contributing to the scientific communities, Prof Lim also applied his water treatment technology to provide safe drinking water to the Asia’s developing communities.