VUV assisted photocatalytic degradation of environmental pollutants and disinfection


VUV assisted photocatalytic degradation of environmental pollutants and disinfection

Fri, 25/08/2017 - 14:40 to 15:40


Prof. Dennis Y.C. Leung
Department of Mechanical Engineering, the University of Hong Kong, Hong Kong

Photocatalytic oxidation (PCO) is one of the fastest developed technologies for the control of environmental pollutants (in both gaseous and aqueous state) as well as for energy production (such as hydrogen generation and dye-sensitized solar cell). The PCO process is normally triggered by the irradiation of UV light. The most widely used UV sources in PCO are 254 nm and 365 nm UV lamp. However, conventional PCO process has disadvantages such as recombination of electron-hole pair in photocatalyst leading to low process efficiency and photocatalyst deactivation. In order to improve the efficiency and stability of the PCO process, UV lamps with partial 185 nm UV irradiation (denoted as VUV lamp) can be used to activate photocatalysts. 185 nm VUV lamps cannot only irradiate photocatalyst but also generate active oxidants such as O and OH radicles, and ozone all of which enhance the oxidation of the organic components in the nearby pollutants. These can also kill microbes in the air and water, and therefore have disinfection effect. In this speech, the results of VUV enhanced photocatalytic degradation of common VOCs (such as toluene and benzene) and water pollutants (such as methyl blue and acrylic wastewater) together with its disinfection effect will be presented and discussed. In addition, ozone is a byproduct generated in the process that can enhance the oxidation and disinfection effects but can also cause harmful effects on our health. The removal of the residue ozone using modified catalyst will also be discussed.


Prof. Dennis Y.C. Leung received his BEng (1982) and PhD (1988) from the Department of Mechanical Engineering at the University of Hong Kong. He had worked with the Hongkong Electric Co., Ltd. for five years heading the air pollution section of the company before joining the University of Hong Kong in 1993. Professor Leung is now a full professor of the Department of Mechanical Engineering specializing in environmental pollution control and renewable & clean energy development. He has published more than 400 articles in this area including 230+ peer reviewed top SCI journal papers. He was invited to publish more than 20 review articles in leading energy and environment related journals. His current h-index is 54 and total citations are more than 15000. He is one of the top 1% highly cited scientists in the world in energy field since 2010 (Essential Science Indicators) until now. Prof. Leung has delivered more than 50 keynote and invited speeches in many conferences as well as public lectures.
Prof. Leung is a chartered engineer, a fellow of the IMechE, and Energy Institute. He is also the Past Chairman of the Institute of Energy (HK Branch), and served as an editorial board member of a number of journals including Applied Energy and Journal of Power & Energy. He is also the Specialty Chief Editor of the Frontiers in Environmental Science since 2014. He currently serves as a board member of the Hong Kong Institution of Science, chairman and member of a few government committees and appeal panel related to sustainable energy and environment, and an external examiner of the IVE Engineering Programme. In 2008, Prof. Leung received the Outstanding Earth Champion Hong Kong award in recognizing his contributions in protecting the environment.