Ezra's Round Table / Systems Seminar: Jillian Goldfarb (Cornell)
Frank H. T. Rhodes Hall 253
Chasing Carbon: Reimagining Valorization Pathways for the Integrated Biorefinery
In the absence of massive government subsidies, the economic viability of large-scale thermochemical conversions of biomass to biofuels is tenuous at best. Pyrolysis converts dry biomass waste into a bio-oil and solid biochar, while hydrothermal processes are efficient ways to convert wet wastes into hydrochars and biocrude. Yet biofuels and biochars require significant upgrading to be of any real value, while hydrochar is unstable and biocrudes are difficult to separate from their aqueous process media. A profitable biorefinery will require new in situ catalytic approaches to modular unit operations, the valorization of all byproducts, and the coupling of conversion processes to maximize renewable fuel extraction and carbon upcycling. Moreover, we need tools for policy makers and entrepreneurs alike that demonstrate the environmental and economic viability of investments in such biorefineries. In this talk, we think beyond the literature norms of “make and characterize a fuel” to envision integrated processes for holistic carbonaceous waste valorization.
Jillian Goldfarb is an associate professor of chemical and biomolecular engineering at Cornell University. She received her Ph.D. from Brown University in chemical engineering in 2008 and B.S. in chemical engineering from Northeastern University in 2004. Research in the Goldfarb group tackles critical "last mile" issues surrounding renewable fuel production from in situ catalysis during thermochemical conversion of biomass to byproduct valorization and technology-policy integration. Work spans fundamental science all the way to large-scale industry collaborations to scale up pyrolysis biofuel production. Her novel concepts for the integrated biorefinery go beyond converting biomass to biofuels. They also produce their own biofuel upgrading and pollution prevention materials by utilizing carbonaceous and heterogeneous organic-inorganic residues remaining after thermochemical conversions.
Her NSF CAREER Award pushed her biorefinery work into the area of Hydrothermal Liquefaction (HTL). One of the advantages of HTL over other biomass conversion techniques is the direct treatment of wet wastes without an energy-intensive pre-drying step. To date, the majority of HTL research explores the impact of process conditions on products produced from a range of feedstocks. However, this approach cannot overcome the primary challenges to widespread application of HTL for biofuels, namely that (1) we cannot accurately control or predict product distributions, which subsequently requires significant downstream upgrading of the biocrude, and (2) the resulting process water requires considerable treatment, making large scale HTL economically infeasible. Controlling hydrothermal liquefaction (HTL) requires us to treat it not as a series of reactions, but rather as a reactive process by which we form supersaturated solutions of aqueous-organic mixtures and a separate organic biocrude. Taking a fundamental thermodynamic approach to HTL and product recovery could accelerate our transition to a renewable energy future by facilitating the design of more efficient and selective HTL processes.
Beyond the biorefinery, Prof. Goldfarb tackles the design of sustainable materials for water treatment and other environmental applications using computational modeling integrated with experimental fabrication and characterization. She and her collaborators developed and validated a new framework on heterogeneous hierarchical porous media for point-of-use water treatment. Using greener fabrication methods (solvent recycling loops, bio-templating and low-temperature processes) we are designing polymer foam scaffolds with high light penetration and water permeability into which we embed photocatalytically active nanocomposites for the destruction of organic pollutants in water.