Researchers peer inside catalyst used in biofuel processing to investigate why it clogs
November 23, 2016 
RICHLAND, Wash. - Catalysts known as zeolites are vital to fuel production and other processes. Coke deposits in zeolites are a costly problem in petroleum refinement and in petrochemical production.
"Understanding coke molecules in zeolites will provide broad benefits across the refinery and renewable energy industries, and zeolite is one of the most highly utilized catalysts," said Karthikeyan Ramasamy, a chemical engineer at the D.O.E.'s Pacific Northwest National Lab.
To explore ways to fix the issue, Ramasamy and other researchers from PNNL, with help from DOE's Lawrence Berkeley National Lab, zoomed in at the highest resolution yet on these problematic carbon-based deposits.
They found zeolites's porous nature makes it a great chemical catalyst, but also traps tiny clusters of carbon-containing molecules that can ultimately disrupt the catalysis process. An uneven distribution of aluminum in the fresh zeolite catalyst causes an uneven distribution of coke deposits during chemical reactions.
"We wanted to understand this coking mechanism and where it blocks the reaction and how it blocks it. By using a combination of techniques we could compare them to one another and form a complete story," said PNNL materials scientist Arun Devaraj, who co-led the study with Ramasamy.
Some of the work was performed at 2 D.O.E. Office of Science User Facilities - EMSL, the Environmental Molecular Sciences Lab on the PNNL campus and the Advanced Light Source at Berkeley Lab.
Read more in Lawrence Berkeley National Laboratory's news release.
Reference: Arun Devaraj, Vijayakumar Murugesan, Jie Bao, Mond F. Guo, Mirosław A. Derewinski, Zhijie Xu, Michel J. Gray, Sebastian Prodinger, Karthikeyan K. Ramasamy. Discerning the Location and Nature of Coke Deposition from Surface to Bulk of Spent Zeolite Catalysts, Scientific Reports, November 23, 2016, DOI: 10.1038/srep37586.
Tags: Energy, Fundamental Science, EMSL, Energy Production, Chemistry, Catalysis, Materials
EMSL, the Environmental Molecular Sciences Lab, is a D.O.E. Office of Science User Facility. Located at Pacific Northwest National Lab in Richland, Wash., EMSL offers an open, collaborative environment for scientific discovery to researchers around the world. Its integrated computational and experimental resources enable researchers to realize important scientific insights and create new technologies. Follow EMSL on Facebook, LinkedIn and Twitter.
Interdisciplinary teams at Pacific Northwest National Lab address many of America's most pressing issues in energy, the environment and national security through advances in basic and applied science. Founded in 1965, PNNL employs 4,400 staff and has an yearly budget of nearly $1 billion. It is managed by Battelle for the D.O.E.'s Office of Science. As the single biggest supporter of basic research in the physical sciences in the United States, the Office of Science is working to address some of the most pressing challenges of our time. For more information on PNNL, visit the PNNL News Center, or follow PNNL on Facebook, Google+, LinkedIn and Twitter.
