Bio: 

Dr. Rui Shi is an Assistant Professor of Chemical Engineering at Pennsylvania State University, with a joint appointment in the Institute of Energy and the Environment. Her research has focused on systems analysis, with current work centered on life cycle assessment (LCA), sustainable process design, and systems-level optimization. Her group develops agile sustainability assessment tools that are applied to a wide range of emerging technologies. Ongoing research spans engineering systems for biofuels and bioproducts, advanced materials and food systems, and waste valorization. Her work has been supported by agencies including the National Science Foundation (NSF), U.S. Department of Energy (DOE), U.S. Department of Agriculture (USDA), and the REMADE Institute. In addition to her research, Rui is passionate about science communication and public engagement, and has collaborated with multiple international organizations and NGOs on sustainable development topics. 

Abstract: 

Translating lab-scale innovations into large-scale sustainability outcomes requires more than technical breakthroughs —it demands systems thinking. As we transition toward a decarbonized and circular economy, systems engineering plays a critical role in designing technologies that are not only technically viable but also economically and environmentally sustainable. Rare earth elements (REEs, consisting of lanthanides, scandium, and yttrium) are considered critical materials and are used in a variety of modern technologies including wind turbines, lasers, consumer devices, and electric vehicles. However, the current production of REEs relies on energy and chemically intensive processes (beneficiation, leaching, solvent extraction, and refinement) from mining REE ores primarily in one geopolitical region, posing significant sustainability and supply chain vulnerabilities. Investigations into more sustainable supplies of REEs from abundant secondary sources, such as impaired waste streams, are vital to securing a stable REE supply chain while also mitigating the environmental risks associated with waste storage and disposal. This work presents a systems-level approach to addressing these challenges by exploring a novel opportunity to recover REEs from phosphogypsum (PG), an abundant industrial waste byproduct of phosphate fertilizer production. With REE contents of ~0.02 wt%, PG could meet the entire annual U.S. REE demand (~9,000 tons/year). We investigated a low technology readiness level (<TRL 3) process that incorporates a bio-inspired
adsorptive separation step to recover a purified REE stream. Using integrated life cycle assessment (LCA), techno-
economic analysis (TEA), and global uncertainty and scenario analysis, we assess the system's environmental
impacts, financial viability, and opportunities for further optimization. The system analysis results provide insights for
advancing sustainable REE recovery from secondary sources and securing critical materials for the clean energy
transition. This work highlights how an integrated framework, combining lab-scale experimental data, process design,
sustainability metrics, and decision analysis, can guide the development of emerging technologies.

Wednesday, April 16, 2025: 

Seminar will start 2:30 PM in Washkewicz Hall, WH405.