Title: Knowledge-based Development of Catalytic Processes
Speaker: Dr. Yanhui Yang (Nanyang Technological University)
Time: 15:00-16:00p.m., Dec. 17th, 2015
Venue: Room 214, 2F of Building No.16, Wushan Campus
Brief introduction to Dr. Yanhui Yang
Dr. Yang received his B.S. degree in chemical engineering from Tsinghua University and Ph.D. degree in chemical engineering from Yale University in 1998 and 2005, respectively. His doctoral advisor is Prof. Gary L. Haller. Dr. Yang joined School of Chemical and Biomedical Engineering (SCBE), Nanyang Technological University (NTU), Singapore as an assistant professor in August 2005 right after He graduated from Yale. Dr. Yang’s primary research area is heterogeneous catalysis over metals and metal oxides. In particular, Dr. Yang is interested in understanding the fundamental catalytic concepts and phenomena using well-defined model catalyst and chemically probed reactions. Dr. Yang has published over 150 research articles, 2 book chapters. Dr. Yang was promoted to be associate professor with tenure in chemical engineering in 2010.
Knowledge-based development of catalytic processes
Yanhui Yang
School of Chemical and Biomedical Engineering
Nanyang Technological University
yhyang@ntu.edu.sg
Abstract:
Two examples will be shown to demonstrate the “knowledge-based” understanding on the catalytic processes and design of novel catalyst. The first example is a classic heterogeneous catalysis approach in which an integrated experimental and computational investigation reveals that the surface lattice oxygen of copper oxide (CuO) nanoleaves activates the formyl C–H bond in glucose and incorporates itself into the glucose molecule to oxidize it to gluconic acid.The reduced CuO catalyst regains its structure, morphology and activity upon reoxidation. The activity of lattice oxygen is shown to be superior to that of the chemisorbed oxygen on the metal surface and the hydrogen abstraction ability of the catalyst is correlated with the adsorption energy. Based on the present investigation, it is suggested that surface lattice oxygen is critical for the oxidation of glucose to gluconic acid, without further breaking down the glucose molecule into smaller fragments, due to C–C cleavage. Using CuO nanoleaves as the catalyst, excellent yield of gluconic acid is also obtained for the direct oxidation of cellobiose and polymeric cellulose, as biomass substrates.
The second example is to attempt metal-organic frameworks (MOFs) as a new member of heterogeneous catalyst, showing great promise for catalytic reactions due to their flexible as well as designable structure and outstanding properties. Further, the potential catalysis application of MOFs can be extended by incorporation varieties of nanoparticles (NPs). A facile encapsulation strategy to incorporate NPs into MOFs family will be introduced and the synthesized NPs/MOFs catalyst exhibits the unprecedented site-selectivity for oxidation of diol and hydrogenation of alkadiene by simple physical space limitation of MOFs pore. A strategy to introduce mesopores to MOF structures will also be investigated to overcome the limitation of pore diffusion resistance in liquid phase reaction.
