Catalytic Conversion of Methane to Partially Oxidized Products over Copper-Exchanged Zeolites

TOPIC:            Catalytic Conversion of Methane to Partially Oxidized Products over Copper-Exchanged Zeolites

SPEAKER:      Dr. Kimberly Dinh, Senior Research Specialist in Dow’s Core R&D: Chemical Science group

DATE:              Tuesday, May 10th

TIME:               6:00 – Introduction

                             6:05 - Carrer Discussion

                             6:15 Technical Presentation

                             7:15 Q&A

COST:               Free, Registration Required          

LOCATION:    Online Zoom meeting

ABSTRACT:   The selective activation and conversion of methane to liquid oxygenated compounds is a grand challenge in catalysis. Although natural gas can be processed industrially in largescale facilities, new catalytic processes are required for the direct, low-temperature conversion of methane to liquid products in small-scale units to exploit highly abundant but difficult-to-access gas reserves in distributed fields or stranded wells. Narsimhan et al. reported the first instance of a continuous, gas phase catalytic process for the direct conversion of methane to methanol using copper-exchanged zeolites by feeding only methane, water, and oxygen at 473 K.1 While this continuous system is an attractive route for the mild conversion of methane to value-added products, fundamental understanding of the reaction pathway and active site is necessary to engineer improved catalysts and an improved process.

Thus, we first demonstrated a reaction pathway where C-H bond scission of methane is rate-limiting and a [Cu-O-Cu]2+ motif as the active site for the selective catalytic conversion of methane to methanol. Water is required for methanol desorption and carbon dioxide is generated from the sequential over oxidation of partially oxidized intermediates and downstream methanol oxidation. Selective partial oxidation was achieved with catalyst samples of high Al content and moderate Cu content (Cu/cage70% selectivity for partial oxidation products at 0.6% methane conversion.3 These findings resulted in a process that can circumvent methane’s selectivity-conversion limit and provide a new avenue of research in product protection to increase methane conversion while maintaining high product selectivity over heterogeneous catalysts. 

1. Narsimhan, K.; Iyoki, K.; Dinh, K.; Roman-Leshkov, Y., Catalytic Oxidation of Methane into Methanol over Copper-Exchanged Zeolites with Oxygen at Low Temperature. ACS Cent. Sci. 2016, 2 (6), 424-429.
2. Dinh, K. T.; Sullivan, M. M.; Narsimhan, K.; Serna, P.; Meyer, R. J.; Dincă, M.; Román-Leshkov, Y., Continuous Partial Oxidation of Methane to Methanol Catalyzed by Diffusion-Paired Copper Dimers in Copper-Exchanged Zeolites. J. Am. Chem. Soc. 2019, 141 (29), 11641-11650.
3. Dinh, K. T.; Sullivan, M. M.; Serna, P.; Meyer, R. J.; Román-Leshkov, Y., Breaking the Selectivity-Conversion Limit of Partial Methane Oxidation with Tandem Heterogeneous Catalysts. ACS Catal. 2021, 11 (15), 9262-9270.

SPEAKER BIOGRAPHY:  Kimberly Dinh (she/her) is a Senior Research Specialist in Dow’s Core R&D: Chemical Science group where she works on catalyst discovery for more sustainable processes such as ethane conversion and waste hydrocarbon upgrading. Prior to Dow, Dinh earned a B.S. in Chemical Engineering from the University of Wisconsin-Madison in 2015, a M.S. of Chemical Engineering Practice in 2017 and a Ph.D. in 2020 in Chemical Engineering from the Massachusetts Institute of Technology under the guidance of Professor Yuriy Román-Leshkov. At MIT, she was an NSF Graduate Research Fellow and was awarded a 2019 Kokes Travel Award by the North American Catalysis Society.

Dinh is a passionate advocate for improving diversity, equity and inclusion in STEM and sports. She served on MIT’s Chemical Engineering Department’s Graduate Student Advisory Board that worked on improving graduate student quality of life and is currently Mid-Michigan AIChE’s Equity, Diversity, and Inclusion Committee Chair and a New Hire co-Chair for Dow’s Young Researchers Community. Dinh also volunteers her time as an assistant coach with the high school golf teams.

In her free time, Dinh enjoys staying active – playing golf competitively and ultimate frisbee recreationally. She also enjoys cooking, bread baking, watching a good TV show, and listening to podcasts.