Date: February 9, 2012
Time: 4:30 PM -
Location: Friend Center Room 006
The first spring semester speaker of the Andlinger Center’s Highlight Seminar Series will be Dr. James E. Miller, Principal Member of the Technical Staff at Sandia National Laboratories. Dr. Miller will address the topic “Solar Thermochemical Conversion of Carbon Dioxide and Water to Hydrocarbon Fuels.” The seminar will take place on Thursday, February 9, 2012 at 4:30PM in Friend Center, Room 006. A reception will follow and all members of the community are invited to attend.
Two of the most daunting problems facing humankind in the twenty-first century are energy security and climate change. The vision of Sunshine to Petrol (S2P) is to address these interconnected challenges by developing a technology for producing solar fuels that is underpinned by deep scientific understanding. A guiding principle is that the technology must be both scalable to the magnitude of the problem and ultimately economically viable. Our vision is captured by one deceptively simple chemical equation:
Solar Energy + x CO2 + (x+1) H2O → CxH2x+2 (liquid fuel) + (1.5x+.5) O2
Practical implementation of this equation may seem far-fetched. Yet, it is representative of the photosynthetic processes responsible for much of life on earth and, as such, summarizes the biomass approach to fuels production. It is our contention however that an additional alternative is needed to complement biofuels. This alternative or alternatives should avoid the inherent limitation on sunlight-to-fuel efficiency imposed by photosynthesis, and additionally should minimize processing losses by providing a very direct pathway to a liquid fuel. We propose that the conversion of CO2 and H2O to CO and H2, which are the universal building blocks for synthetic fuels, should serve as the basis for this revolutionary alternative, and that the sunlight be used in the form of heat. More specifically we advocate accomplishing the conversion via a solar-driven two-step metal oxide thermochemical cycle. A thermochemical cycle can be visualized as an engine that converts heat to chemical work. Creating a device that in effect applies captured sunlight to reverse combustion poses numerous chemical, materials, and engineering challenges.
In this talk the basic principles of thermochemical cycles will be introduced and progress made towards implementation of these principles will be discussed. We have recently demonstrated solar-driven conversion of CO2 to CO at 1.7% efficiency in a first-of-kind prototype known as the counter-rotating-ring receiver/reactor/recuperator (CR5). Advances in characterizing and understanding the remarkably dynamic behavior of the active metal oxide materials that are the heart of these systems will be discussed. The results of systems and economic analyses will be briefly introduced to provide important context.
This work was supported by the Laboratory Directed Research and Development program at Sandia National Laboratories, in the form of a Grand Challenge project entitled “Reimagining Liquid Transportation Fuels: Sunshine to Petrol,” Ellen Stechel, program manager. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy’s National Nuclear Security Administration under contract DE-AC04-94AL85000.
Jim Miller has been involved in heterogeneous catalysis and chemical processing research at Sandia National Laboratories for over 20 years. He is the principal investigator of the Sunshine to Petrol Grand Challenge project where his activities include the development of a new high temperature thermochemical water- and carbon dioxide – splitting reactor and composite oxide materials for that reactor. Other recent activities have included the development and characterization of novel nanostructured Pt materials, catalysts for solid oxide and PEM fuel cells, catalysts for selective hydrocarbon oxidation (to olefins and syngas), catalysts for NOx storage and reduction, and materials and concepts for low-temperature hydrogen combustion. He has also been involved in desalination, developing and characterizing catalysts for upgrading (hydrotreating/hydrocracking) coal and petroleum liquids, characterizing mass transfer in novel 3-dimensional catalytic monoliths, and developing and characterizing processes for lignin depolymerization. Early in his tenure at Sandia, he worked on radioactive waste disposal/treatment technologies including steam reforming and cesium-selective crystalline silicotitanate ion exchangers. Jim holds a B.S. degree in Chemical Engineering from Texas A&M University and a Ph.D. in Chemical Engineering from the University of Texas at Austin.