Fikile R. Brushett, PhD

Massachusetts Institute of Technology

Friday, November 4, 2022

9:30 AM

102 Benedum Hall

Towards Electrochemical Carbon Dioxide Capture

Using Soluble, Redox-active Carriers

Abstract:

Deep, society-wide decarbonization is a grand challenge of the 21^st century, requiring the development, manufacture, and deployment of transformative carbon-neutral and carbon-negative technologies on global scale.  Carbon dioxide (CO₂) capture coupled with storage or conversion is projected to play a key role in mitigating and even reversing carbon emissions.  Present-day carbon capture processes rely on thermochemical cycles where solvents/sorbents absorb and release CO₂ at lower and higher temperatures, respectively.  While functional and available at the commercial scale, these embodiments are energetically intensive and typically rely on fossil fuel derived heat for CO₂ desorption, ultimately limiting efficacy.  Electrochemical approaches may enable lower energy CO₂ separations, as electrode potential can be modulated to selectively activate sorbents rather than temperature and pressure swings that impact the entire capture media.  In addition, such systems may enable direct integration of renewables, modular deployment, and operation at ambient conditions.

While there are several promising electrochemical approaches for CO₂ separation, I will focus on systems that exploit soluble, redox active carriers with CO₂ binding strengths that vary with changes in oxidation state.  Within this nascent field, most efforts seek to discover stable carrier molecules and electrolyte formulations that enable high separation capacities and energetically-efficient operation.  However, at this early stage of development, modeling frameworks hold value in describing key relationships between molecular properties, cell performance, and system design.  Such knowledge may, in turn, inform ongoing molecular and device engineering campaigns, giving researchers a means of estimating carrier molecule effectiveness and reactor performance.  In this talk, I will describe our efforts to develop thermodynamic, electrochemical, and techno-economic models to articulate the performance-determining relationships between constituent components, configurations, and operating envelopes of electrochemical CO₂ separation systems.  I will also provide examples of how insights gained from modeling can focus experimental research efforts.

Bio: Fikile Brushett is an Associate Professor in the Department of Chemical Engineering at the Massachusetts Institute of Technology.  Before joining the Institute, he received his Ph.D. in Chemical Engineering from the University of Illinois at Urbana-Champaign and performed postdoctoral work in the electrochemical energy storage group at Argonne National Laboratory.  His research group seeks to advance the science and engineering of electrochemical technologies that enable a sustainable energy economy.  He is especially interested in the fundamental processes that define the performance, cost, and lifetime of present day and future electrochemical systems.  His group currently works on rechargeable batteries for grid energy storage and electrochemical processes for resource management.  He also serves as the Research Integration co-Lead for the Joint Center for Energy Storage Research, a DOE-funded Energy Innovation Hub.