The Institute for Integrated Catalysis (IIC) at Pacific Northwest National Laboratory (PNNL) in Washington State is advancing the ability to control chemical transformations and chemical-electrical energy interconversions to significantly reduce the global energy system's carbon footprint. Our strategy is to develop new technologies that can operate at lower temperatures and pressures, and with higher selectivities. To achieve this, we learn from applied problems, develop a foundational understanding of the catalytic chemistries, and design new catalysts and catalytic synthesis routes. Research areas central to this strategy, as well as other environmentally friendly technologies encompassed within the IIC, include the following:
- Using electrocatalysis to produce hydrogen and hydrogenated compounds (focus of the Center for Molecular Electrocatalysis, an Energy Frontier Research Center (EFRC) led by PNNL, and of the laboratory-wide Chemical Transformations Initiative)
- Adding hydrogen to oxo-functionalized renewable carbon resources (i.e., biomass components or carbon dioxide, which store, in essence, solar energy in chemical bonds and allow use of existing chemistry and infrastructure)
- Cleaving and manipulating carbon-carbon and carbon-heteroatom bonds (i.e., ensuring the cleanest energy carriers possible and optimally produced chemicals)
- Low-temperature vehicle emission control catalysis.
These activities involve basic and applied research to understand the chemical aspects of catalysis and to use it to advance both science and practical applications.
The key PNNL programs that focus on advancing the science and technology in these critical areas are briefly summarized below.
Basic Research: Answering Tough Questions
Core Basic Energy Sciences Catalysis Program: Sponsored by the U.S. Department of Energy (DOE), our research focuses on gaining a fundamental understanding of catalytic transformations that reductively convert oxo-functionalized carbon resources, such as bio-derived molecules and carbon dioxide, using acid-base as well as metal-catalyzed pathways. Our strategy is to bridge catalysis disciplines, by exploring molecular and atomistic pathways of selected reactions on catalysts spanning from single-crystal surfaces to heterogeneous complexes to molecular and bioinspired complexes. Identifying common themes in the fundamentals of the elementary steps of reaction sequences will open new possibilities to develop strategies in catalysis by mutual learning. By emulating two properties of enzymes, the spatial constraints at enzyme active sites and the chemical functionalities around the site, we determine catalyst design principles to enhance catalytic activity at lower temperatures and levels than practiced today.
Energy Frontier Research Center (EFRC): Center for Molecular Electrocatalysis: At the Center for Molecular Electrocatalysis, an EFRC funded by DOE's Office of Science, PNNL scientists and university partners are advancing transformational developments on the design of molecular electrocatalysts for the interconversion of electricity and fuels. The EFRC is providing the insights to understand, predict, and control the intramolecular and intermolecular flow of protons in electrocatalytic multi-proton, multi-electron processes of critical importance to a secure energy future, including H2, O2, and N2. The target reactions are required to design catalysts for precise proton delivery in reactions of rising complexity. We focus on identifying, understanding, and developing the scientific principles that allow us to realize such catalysts.
Early Career Program: Combined Capture and Conversion of CO2: As part of an early career research grant from DOE's Office of Science, IIC member David Heldebrant and his collaborators are combining experiment and theory to explore potentially new heterogeneous, micro-domain solvent structures in switchable ionic liquids. Determining how these structures affect separation, concentration, and conversion of carbon dioxide into energy carriers is the focus of the early career program.
Physical Biosciences Program: Enzymatic Energy Conversion: This research focuses on elucidating the core principles used by enzymes that catalyze energy-relevant reactions, such as H2 production and oxidation, carbon dioxide reduction, and N2 reduction. The suite of enzymes that catalyze these reactions operate with high efficiency under mild conditions. We use our team's wide-ranging capabilities, including biochemistry, kinetics, advanced computational methods, single-molecule imaging, and molecular catalyst functionalization, to determine how these enzymes efficiently use energy. This knowledge will be essential to designing next-generation synthetic molecular catalysts for industry.
From Basic to Applied
Chemical Transformations Initiative: Carbon-containing feedstocks that can be transformed into zero-carbon footprint products, either liquid fuel or valuable chemical intermediates, are abundant but highly decentralized. In the Chemical Transformations Initiative, we are developing the science and engineering that will serve as a foundation of new technologies to be implemented at a small scale (typically less than the equivalent of 200 barrels of oil per day). The small-scale processing needs to occur at temperatures and pressures close enough to ambient that the reactants and products will remain in the liquid phase. Therefore, we are designing new catalysts that are very active, selective, and durable when confronted with liquid phase reaction media, likely rich in water and high concentrations of corrosive chemical species.
Applied Research: Solving Real World Problems
Vehicle Emissions: The IIC supports DOE's vehicle technologies mission of advanced combustion engine R&D through its work on emissions controls technologies that enable improved engine designs. We have developed expertise and capabilities for this work in large part by programs funded by DOE's Office of Science. For example, our work in efficient particulate controls, hydrocarbons/carbon monoxide oxidation, and NOx trapping and reduction catalysts involves the use of sophisticated surface science techniques, advanced computational chemistry, modeling and simulation, and systems optimization. We also employ state-of-the-art characterization tools at the Environmental Molecular Sciences Laboratory (EMSL), as well as facilities funded by DOE's Office of Basic Energy Sciences within the IIC. Our work focuses on reducing efficiency losses in emissions control devices with improved catalyst materials and processes. We are minimizing regeneration penalties, optimizing systems, and enabling new combustion strategies.
Bioenergy Technologies Office Program: The DOE Bioenergy Technologies Office (BETO) focuses on accelerating the development and deployment of cost-competitive technologies to convert the nation's abundant domestic, renewable biomass resources into advanced biofuels and bio-based products, including cutting-edge technologies designed to produce “drop-in” biofuels. Utilizing these domestic sources of energy helps promote U.S. competitiveness, jobs, and national security. The program provides supports for converting biomass into high-value chemicals and products historically derived from petroleum that can simultaneously enhance the economics of biofuel production. Breakthroughs in catalytic bioconversion technologies and ensuring that these technologies can be scaled up provide the risk reduction needed by industry. PNNL is a recognized leader in the applying science to the production of fuels and chemicals. Recently, we have worked successfully with industry partners to develop an alcohol-to-jet fuel catalytic process from waste gases. The process is currently being scaled up. Additionally, we have developed a process that uses high pressure and temperature to convert wet sludge to biocrude oil on very short time scales.
Fuel Cell Technology Office Program: Fuel cells are being considered as one of the most attractive—efficient and clean—technologies for electric power generation. Catalysis plays an important role in fuel cell development. We are conducting detailed studies of both oxygen reduction kinetics at the cathode/electrolyte interface and fuel oxidation kinetics at the anode/electrolyte interface. A combination of advanced electrochemical techniques and surface science methods is being used to elucidate the mechanism of these reactions and identify rate-determining step(s). In addition to electrochemical catalyst development, PNNL is a leader in thermochemical hydrocarbon processing for hydrogen production. We have pioneered new catalysts and reactors for turning bio-derived liquids into hydrogen, removing sulfur from fuels and subsequent reforming, cleaning up hydrogen gas, and using hydrocarbons as hydrogen carriers for safe hydrogen transportation.