Shell Seminar Series

Bio

Dr. Susannah Scott is a Distinguished Professor in both Chemical Engineering and in Chemistry & Biochemistry at the University of California, Santa Barbara. She received her Ph.D. in Inorganic Chemistry from Iowa State University, under the direction of Jim Espenson and Andreja Bakac, for her work on the activation of O2 and transition metal-catalyzed oxidation mechanisms. She was awarded a NATO Postdoctoral Fellowship for work with Jean-Marie Basset at the Institut de recherches sur la catalyse (CNRS) in Lyon, France. In 1994, she joined the faculty of the University of Ottawa (Canada), where she was named a Canada Research Chair. In 2003, she moved to the University of California, Santa Barbara, where she currently holds the Duncan and Suzanne Mellichamp Chair in Sustainable Catalysis and is Chair of the Santa Barbara Division of the University of California’s Academic Senate. She is an Executive Editor for ACS Catalysis, and a member of the Board of Reviewing Editors for Science. Her research interests include the design of heterogeneous catalysts with well-defined active sites for the conversion of conventional and unconventional carbon-based feedstocks, including the use of renewable and recycled carbon.

Abstract

Valorization of polyolefins via tandem catalytic upcycling, from monomers to higher value molecules

The use of polyolefins to make small molecules, not limited to monomers which can be repolymerized, is an intriguing approach to recycle carbon and thereby keep plastic out of the natural environment. While catalytic hydrogenolysis leads to lower value alkanes, tandem ethenolysis-isomerization allows the selective conversion of polyethylene to the commodity monomer propylene. Hydrogen redistribution in the absence of added H2 can achieve tandem hydrogenolysis and dehydrocycloaromatization, resulting in higher value alkylaromatics at moderate reaction temperatures. The coupled reactions are greatly accelerated by the use of bifunctional hydrocracking catalysts whose acidity can be used to tune the selectivity towards surfactant-range alkylbenzenes. The key rate-determining and selectivity-controlling steps involve Brønsted acid catalysis. Unexpectedly, the presence of low pressure H2 in the reactor enhances rather than suppresses alkylbenzene formation, while suppressing undesired polyaromatic formation and accelerating the desired reduction in molecular weight. The number of alkyl substituents on the aromatic rings can be optimized via catalytic transalkylation. Other tandem processes, including the selective conversion of polyethylene to monomers under mild reaction conditions, can be designed to achieve alternative desired reaction outcomes.

Bio

Dr. Sibani Lisa Biswal is the William M. McCardell Professor in the Department of Chemical and Biomolecular Engineering and Senior Associate Dean in the George R. Brown School of Engineering at Rice University in Houston, Texas. She has a B.S in chemical engineering from Caltech and a Ph.D. in chemical engineering from Stanford University. She leads the Soft Matter Engineering Laboratory, where she focuses on establishing connections between the rheological behaviour of particulate and multiphase systems. Her research aims to uncover new insights and ideas that can be used to engineer innovative solutions for a diverse range of technological challenges in the fields of materials and energy.

Abstract

Physicochemical Characterization of Asphaltenes Using Microfluidic Porous Media

Asphaltenes constitute the heaviest and most polarizable fraction of crude oil. They are usually referred to as the “cholesterol of petroleum” because of their tendency to aggregate and precipitate, causing clogging problems not only in the wellbore and near wellbore regions, but also in pipelines and production equipment and facilities.  Microfluidic devices, which mimic the characteristics of reservoir rocks, have emerged as powerful tools for studying the transport, reactions, and chemical interactions of fluids in the oil and gas industry. By understanding microscale phenomena, these devices have improved the design of macroscale industrial processes. A notable advancement is in chemical analysis under flowing conditions, where microfluidics provide in situ imaging. This imaging, combined with other chemical characterization methods, offers detailed insights into the interactions between oil, water, and added chemicals at the pore scale. I will describe the use of microfluidic devices in providing new physical, chemical, and dynamic information on asphaltene. Examples of successful applications will be demonstrating new remediation strategies to addressing key asphaltene-related problems in the oil and gas industry.

Bio

Akif Tezcan is a Professor in the Department of Chemistry and Biochemistry and a member of the Materials Science and Engineering (MSE) Program and the Institute of Materials Discovery and Design at UCSD.  He was educated at the German High School in Istanbul, Macalester College in St. Paul, MN (BS in Chemistry and Biology) and Caltech in Pasadena, CA, USA (PhD in Bioinorganic Chemistry with Harry Gray), followed by postdoctoral research at Caltech as a Helen Hay Whitney fellow (with Doug Rees). His research program at UCSD, started in 2005, focuses on developing new chemical tools and strategies to study biological nitrogen fixation, to design functional proteins and enzymes, and to create new protein-based materials.  Akif and his group’s research program at UCSD has been recognized with an NSF CAREER Award, Sloan Fellowship, Beckman Young Investigator Award, Frasch Foundation Award, Moore Distinguished Scholarship (Caltech), Leslie Orgel Scholarship (UCSD), Saltman Lectureship at the GRC on Metals in Biology, Swift Lectureship (Caltech), Witten Lectureship (UNC), Schaeffer Lectureship (U. New Mexico), the Early Career Award from the Society of Biological Inorganic Chemistry, and a Guggenheim Fellowship.

Abstract

Chemical Design of Functional Protein Materials

Proteins represent the most versatile building blocks available to living organisms or the laboratory scientist for constructing functional materials and molecular devices. Underlying this versatility is an immense structural and chemical heterogeneity that renders the programmable self-assembly of proteins an extremely challenging design task. To circumvent the challenge of designing extensive non-covalent interfaces for controlling protein self-assembly, our group has endeavored to use chemical bonding strategies based on fundamental principles of inorganic chemistry and molecular symmetry. These strategies (combined with some supramolecular and polymer chemistry) have resulted in discrete or infinite, 0-, 1-, 2- and 3D protein architectures that display high structural order over large length scales, yet are dynamic, adaptive and possess new emergent chemical/physical properties. In this talk, I will present some of these functional “bioinorganic materials” constructed in our laboratory.

Bio

Dr. Xun Tang obtained his Ph.D. in Chemical Engineering from Georgia Tech in 2016, with his thesis work focused on optimal control for colloidal self-assembly. He then worked at postdoc at UC Riverside and Penn State University, before he joined Ford as a research engineer in 2018.

Since 2020, Dr. Xun Tang joined the Cain Department of Chemical Engineering at Louisiana State University as a tenure track Assistant Professor. The current focus of research in his lab is on machine learning, optimal control, molecular self-assembly, and synthetic biology.

Abstract

Model-based Control for Stochastic Systems

Control theory studies the design strategies to deliver desired performance of the process of interest. Applications of control theory has benefited a wide range of fields from self-assembly to gene expression regulation.

In this talk, I will focus on a colloidal self-assembly system and a wound healing process to discuss the application of mathematical modeling, including both data-driven and first principle-based approaches and control theory, in tackling challenging issues with colloidal self-assembly and the regulation of biological processes. Specifically, I will talk about the current efforts from the group on developing a generalizable optimal control framework for the control of a high dimensional stochastic colloidal self-assembly process, especially on state representation and control inputs identification. I will also talk about the ongoing work on how we leverage model-based analysis and synthetic gene circuits to realize regulation of wound healing process.

Bio

Dr. Jason Weaver earned a Ph.D. degree from Stanford University in 1998, working with Robert Madix to investigate alkane adsorption on transition metal surfaces using molecular beam scattering techniques and molecular dynamics simulations. He joined the faculty at the University of Florida in 1999, where he is currently the Dow Chemical Company Foundation Professor of Chemical Engineering, and an Affiliate Professor of Chemistry. Prof. Weaver’s research interests are in heterogeneous catalysis and the chemistry and physics of solid surfaces. His research aims to develop a molecular-level understanding of surface catalyzed reactions through application of ultrahigh vacuum and in situ surface analysis methods as well as molecular simulations. Specific topics of focus include the growth and surface chemistry of late transition-metal oxides, mixed-metal oxides and dilute alloy surfaces, and the oxidation chemistry of small molecules particularly alkanes.

Abstract

Oxidation of light alkanes on the IrO₂(110) surface

Developing catalysts that can efficiently convert light alkanes to value-added products is critical to achieving global decarbonization and could have a transformative impact on the chemical industry. Catalytic combustion also remains vital for mitigating the release of harmful compounds in power generation applications that utilize natural gas. In this talk, I will discuss our investigations of alkane oxidation on IrO₂(110) thin films in ultrahigh vacuum as well as under catalytic conditions. I will discuss studies of the growth of IrO₂(110) films, and our discovery of low temperature C-H activation of light alkanes (C₁-C₃) on IrO₂(110) and the subsequent oxidation chemistry. I will also discuss microkinetic simulations of the catalytic oxidation of CH₄ on IrO₂(110) and their accuracy in reproducing measurements of the catalytic kinetics as well as species coverages determined using operando x-ray photoelectron spectroscopy (XPS). Our kinetic studies show that IrO₂(110) films are highly active for the catalytic combustion of CH₄ at moderate temperatures (~500-650 K), and measurements using near-ambient pressure, synchrotron XPS demonstrate that high coverages of OH groups and CH_yO₂ species form on IrO₂(110) during catalytic CH₄ oxidation at all conditions studied. This information guided our development of a microkinetic model, derived from density functional theory calculations, that accurately reproduces the measured kinetic behavior and identifies how different surface species mediate the reaction kinetics. Lastly, I will highlight our efforts to enhance the partial oxidation selectivity of IrO₂(110) by substituting Cl into the surface and synthesizing IrO₂-based mixed metal-oxides. The exceptional activity of IrO₂(110) toward alkane C-H bond cleavage, along with the ability to manipulate the subsequent oxidation pathways, may provide new opportunities for developing IrO₂-based catalysts that are capable of directly and efficiently transforming light alkanes to value-added products.

Bio

Dr. Reginald E. Rogers, Jr. is an Associate Professor and Director of Graduate Studies in the Department of Chemical and Biomedical Engineering at the University of Missouri.  He received his B.S. degree from the Massachusetts Institute of Technology, his M.S. degree from Northeastern University, and his Ph.D. degree from the University of Michigan, all in Chemical Engineering.  From 2010-2012, Dr. Rogers served as a Postdoctoral Fellow in the Department of Chemical Engineering at Rochester Institute of Technology.  He then served the faculty at RIT from 2012-2019 before transitioning to the University of Missouri. His research interests are focused on improved water resources using novel nanomaterials and advanced cathode materials for sodium-ion batteries.  As an educator, Dr. Rogers has continuously integrated undergraduate students within his research efforts to broaden their perspectives on their potential roles on societal challenges as rising engineers.  He has given numerous presentations and published multiple articles on his research in addition to education and DEI-related papers.  Dr. Rogers has been recognized for his teaching, research, and service efforts through numerous invited speaking engagements and awards.  He has been invited to speak on the responsible development of nanotechnology at the National Academies.  He is the inaugural recipient of the Award for Excellence in Chemical Engineering Teaching Practice presented by the Education Division of the American Institute of Chemical Engineers.  He is also the recipient of the Joseph Cannon Award in Chemical Engineering, the Dr. Henry C. McBay Outstanding Teaching Award, and the Dr. Tyrone Mitchell Mentor on the Map Award from the National Organization for the Professional Advancement of Black Chemists and Chemical Engineers; the Dr. Janice A. Lumpkin Educator of the Year Award from the National Society of Black Engineers; and the American Chemical Society Stanley C. Israel Regional Award for Advancing Diversity in the Chemical Sciences. 

Abstract

Carbon Nanomaterial Aerogels for Wastewater Treatment: Translating the Research Experience to Promote Diversity, Equity, and Inclusion Efforts

Carbon nanomaterials have become of high interest in many applications.  One area of interest involves separation techniques towards clean water.  As one of the Grand Challenges, providing improved clean water for the growing population will continue to be of great need.  Carbon nanomaterials have been established as one pathway to creating enhanced purification systems that could improve the way in which clean/purified water is obtained.  Recently, we have established the use of carbon nanomaterial aerogels as a means for rapid adsorption of contaminants with high uptake capabilities.  Depending on the mass loading of carbon nanomaterials and the contaminant of interest, adsorption results provide a potential pathway for using these aerogels in continuous flow processes.  Integration of students in this research effort has been of high importance, especially when focusing on diversity, equity, and inclusion.  The term “DEI” has become commonplace in many vision statements for education institutions and corporations.  However, has the use of DEI blinded us to what it means to “practice what we preach”?  On many campuses, there is still a struggle to implement DEI initiatives due to internal and external forces.  A grassroots understanding of diversity, equity, and inclusion needs to happen in order people to properly engage in practicing its true meaning.  This starts by understanding the broad array of groups that are impacted by our daily actions.  In this talk, recent results on utilizing CNM aerogels for water purification will be connected to ideas on best practices for enhancing the culture around the campus and in the research laboratory.  A deep dive into the integration of Diversity, Equity, and Inclusion will open the door for more in-depth conversations on how diversity is only one element of creating an environment where people, especially undergraduate students, feel a sense of belonging.  Change and value must be embraced to cause each individual to self-reflect on their own actions towards promoting DEI at all levels.

Bio

Jingjie Wu is an associate professor of chemical engineering at the University of Cincinnati. He holds a Ph.D. in Chemical Engineering from the University of South Carolina and completed his postdoctoral studies at Rice University. His research endeavors are centered on pioneering advancements in catalysts, electrodes, and processes for the environmentally sustainable synthesis of chemicals and fuels utilizing C₁ small molecules feedstock. His contributions to the field have been recognized by the University of Cincinnati’s Research Award for Early Career Faculty and the ORAU Ralph E. Powe Junior Faculty Enhancement Award. Additionally, he has been recognized as an Emerging Investigator or Rising Star by several high-end journals, such as Journal of Materials Chemistry A, Chemical Communications, Chem Catalysis, and Energy & Fuels.

Abstract

Transitioning Chemical Manufacturing to Net Zero: Electrochemical Conversion of Carbon Dioxide to Valuable Chemicals

CO₂ capture and utilization can be a feasible way for the net-zero transition of the chemical industry when concerted efforts build up the carbon-capture-and-utilization value chain worldwide. The frontier research on CO₂ electrolyzers focuses on increasing selectivity toward a single product, promoting energy efficiency, reducing CO₂ crossover, and enhancing stability. This presentation will introduce our recent progress in developing tandem electrodes for promoting the C-C coupling (rate-determining step, RDS) kinetics and designing catalysts based on reaction descriptor for steering the post-C-C coupling selectivity (selectivity-determining step, SDS). The collective control of RDS and SDS could direct CO₂ conversion to C₂H₄ with 70% Faradaic efficiency and a partial current density of >1.0 A cm^-2. This presentation will also address the coupled carbon and energy efficiencies by pairing CO₂ reduction with efficient oxygen evolution reaction under pure water conditions. Finally, this talk will present the visualization of electrode flooding causing CO₂ reduction performance degradation and discuss strategies to mitigate flooding when operating at a current density of industrial relevance.

Bio 

Davi Salmin is a Subsea Flow Assurance (FA) and Systems Engineer working for Shell. He is experienced in offshore deepwater exploration and production, specializing in FA systems engineering and technology development. Davi’s role includes improving operational efficiency and developing solutions for complex FA challenges. He holds a PhD in Chemical Engineering from the Colorado School of Mines and is skilled in advanced technical modeling and collaborations with both internal and external multi-disciplinary teams.  

Abstract

Flow Assurance in Deepwater Oil Production: Assessing Risks and Technological Gaps

Subsea tiebacks in oil and gas production often face significant flow assurance (FA) challenges, such as asphaltenes, wax, sand, scale, and hydrates. With increasing scrutiny on capital expenditures for new projects and the trend towards deploying longer and deeper flowlines, it is crucial to thoroughly understand and address these risks in a safe and cost-effective manner.

This presentation aims to provide insights into FA risk assessment for oil single-tie backs, highlighting the role of technology development as a critical enabler rather than a “nice to have”. The talk will address FA risks considering variables such as flowline length, insulation, production rates, and fluid properties and provide a gap analysis highlighting existing technologies that can mitigate these risks but pinpointing areas where further advancements are necessary.

Bio

Michael R. King is the E.D. Butcher Chair of Bioengineering at Rice University, and Special Advisor to the Provost on Life Science Collaborations with the Texas Medical Center. He is also a Scholar of the Cancer Prevention and Research Institute of Texas (CPRIT). Previously, King was the J. Lawrence Wilson Professor and Department Chair of Biomedical Engineering at Vanderbilt University, and before that was the Daljit S. and Elaine Sarkaria Professor at Cornell University. He completed a PhD in chemical engineering at the University of Notre Dame and postdoctoral training in bioengineering at the University of Pennsylvania. He has written textbooks on the subjects of statistical methods and microchannel flows, and has received several awards including the NSF CAREER Award, Outstanding Research Awards from the American Society of Mechanical Engineers and the American Society of Clinical Chemistry, and the Christopher Jacobs Award for Excellence in Leadership. King is a Fellow of the American Institute of Medical and Biological Engineering (AIMBE), Biomedical Engineering Society (BMES), International Academy of Medical and Biological Engineering (IAMBE), American Association for the Advancement of Science (AAAS), and the National Academy of Inventors (NAI), and served as founding Vice President of the International Society of Bionic Engineering. Since 2013 he has been the Editor-in-Chief of Cellular and Molecular Bioengineering, an official journal of the BMES. He previously served as Chair of the BME Council of Chairs, and Chair of the AIMBE College of Fellows.

Abstract

Cancer Mechanotherapy: Harnessing Cellular Mechanotransduction to Understand and Treat Metastatic Cancer

Many types of cancer metastasize via the bloodstream, where circulating tumor cells (CTCs) originating from the primary tumor can travel through the circulation or lymphatic system and engraft in distant organs. Previously, our laboratory found that cancer cells exposed to physiological levels of fluid shear stress (FSS) are dramatically more susceptible to undergoing apoptosis via TRAIL protein, inspiring a new therapeutic drug delivery approach to target metastatic cells in the circulation. The FSS response of CTCs and their neutralization by nanoscale liposome conjugation to the surface of circulating immune cells has been demonstrated with in vitro cell line experiments, orthotopic mouse models of metastasis, and analysis of primary CTC aggregates isolated from metastatic cancer patients. We learned that this shear stress response is primarily mediated by Piezo1 activation, and is modulated by interactions with aggregated stromal cells such as cancer-associated fibroblasts. Interestingly, we also discovered that FSS activation of Piezo1 dramatically enhances the activation of T cells and dendritic cells, which may have important implications for various immunotherapy applications. Our ongoing research is also exploring whether cellular mechanosensors can be non-invasively stimulated using focused ultrasound, to improve clinical outcomes in cancer.

Bio

Andrew Ferguson is a Professor and Vice Dean for Education and Outreach at the Pritzker School of Molecular Engineering at the University of Chicago. He received an M.Eng. in Chemical Engineering from Imperial College London in 2005, and a Ph.D. in Chemical and Biological Engineering from Princeton University in 2010. From 2010 to 2012 he was a Postdoctoral Fellow of the Ragon Institute of MGH, MIT, and Harvard in the Department of Chemical Engineering at MIT. He commenced his independent career as an Assistant Professor of Materials Science and Engineering at the University of Illinois at Urbana-Champaign in August 2012 and was promoted to Associate Professor of Materials Science and Engineering and Chemical and Biomolecular Engineering in January 2018. He joined the Pritzker School of Molecular Engineering in July 2018. His research uses theory, simulation, and machine learning to understand and design self-assembling materials, macromolecular folding, and antiviral therapies. He is the recipient of a 2020 Dreyfus Foundation Award for Machine Learning in the Chemical Sciences and Engineering, 2018/19 Junior Moulton Medal of the Institution of Chemical Engineers, 2017 UIUC College of Engineering Dean’s Award for Excellence in Research, 2016 AIChE CoMSEF Young Investigator Award for Modeling & Simulation, 2015 ACS OpenEye Outstanding Junior Faculty Award, 2014 NSF CAREER Award, 2014 ACS PRF Doctoral New Investigator, and was named the Institution of Chemical Engineers North America 2013 Young Chemical Engineer of the Year. He is the co-founder of the protein engineering company Evozyne, Inc. (www.evozyne.com).

Abstract

Artificial Intelligence for Biomolecular Backmapping and Functional Protein Design

Data-driven modeling and deep learning present powerful tools that are opening up new paradigms and opportunities in the understanding, discovery, and design of soft and biological materials. In the first part of this talk, I will describe approaches based on flow matching to restore all-atom resolution to coarse-grained molecular dynamics simulations of proteins and DNA to help break the time scale barrier in biomolecular simulations. In the second part of the talk, I will discuss recent work on autoregressive discrete diffusion models employing physicochemical and natural language conditioning for data-driven functional protein design within machine learning-guided directed evolution campaigns.