Peer-reviewed publications
For the most up-to-date list, please refer to my Google Scholar page.
2024
Mixed community microalgal wastewater treatment technologies have the potential to advance the limits of technology for biological nutrient recovery while producing a renewable carbon feedstock, but a deeper understanding of their performance is required for system optimization and control. In this study, we characterized the performance of a 568 m3·day–1 Clearas EcoRecover system for tertiary phosphorus removal (and recovery as biomass) at an operating water resource recovery facility (WRRF).
H. R. Molitor, G.-Y. Kim, E. Hartnett, B. Gincley, M. M. Alam, J. Feng, N. M. Avila, A. Fisher, M. Hodaei, Y. Li, K. McGraw, R. D. Cusick, I. M. Bradley, A. J. Pinto, and J. S. Guest. Intensive Microalgal Cultivation and Tertiary Phosphorus Recovery from Wastewaters via the EcoRecover Process. Environ. Sci. Technol. 2024, 58 (20), 8803–8814.
25.
Characterizing the Opportunity Space for Sustainable Hydrothermal Valorization of Wet Organic Wastes
Resource recovery from wet organic wastes can support circular economies by creating financial incentives to produce renewable energy and return nutrients to agriculture. In this study, we characterize the potential for hydrothermal liquefaction (HTL)-based resource recovery systems to advance the economic and environmental sustainability of wastewater sludge, FOG (fats, oils, and grease), food waste, green waste, and animal manure management through the production of liquid biofuels (naphtha, diesel), fertilizers (struvite, ammonium sulfate), and power (heat, electricity). Overall, our work demonstrates the potential of HTL-based resource recovery systems to reduce the costs and carbon intensity of resource-rich organic wastes.
J. Feng, Y. Li, T. J. Strathmann, and J. S. Guest. Characterizing the Opportunity Space for Sustainable Hydrothermal Valorization of Wet Organic Wastes. Environ. Sci. Technol. 2024, 58 (5), 2528–2541.
2023
Catalytic hydrothermal processing is a promising technology for the production of biofuels used in transportation to alleviate the energy crisis. An important challenge for these processes is the need for an external supply of hydrogen gas to accelerate the deoxygenation of fatty acids or lipids. This study reports on the use of various alcohol and carboxylic acid amendments as sources for in situ hydrogen production to accelerate Ru/C-catalyzed hydrothermal deoxygenation of stearic acid. Addition of these amendments significantly increases yields of liquid hydrocarbon products, including the major product heptadecane, from stearic acid conversion at subcritical conditions (330 °C, 14–16 MPa during the reaction). This research provided guidance for simplifying the catalytic hydrothermal process of biofuel production, making the production of the desired biofuel in one pot possible without the need for an external H2 supply.
J. Wang, X. Yao, Y. Li, J. Zhang, C. Zhao, and T. J. Strathmann. Catalytic Hydrothermal Deoxygenation of Stearic Acid with Ru/C: Effects of Alcohol- and Carboxylic Acid-Based Hydrogen Donors. ACS Omega 2023, 8 (22), 19969–19975.
Achieving safely managed sanitation and resource recovery in areas that are rural, geographically challenged, or experiencing rapidly increasing population density may not be feasible with centralized facilities due to space requirements, site-specific concerns, and high costs of sewer installation. Nonsewered sanitation (NSS) systems have the potential to provide safely managed sanitation and achieve strict wastewater treatment standards. One such NSS treatment technology is the NEWgenerator, which includes an anaerobic membrane bioreactor (AnMBR), nutrient recovery via ion exchange, and electrochlorination. The system has been shown to achieve robust treatment of real waste for over 100 users, but the technology’s relative life cycle sustainability remains unclear. This study characterizes the financial viability and life cycle environmental impacts of NEWgenerator and prioritizes opportunities to advance system sustainability through targeted improvements and deployment.
S. Watabe, H. A. C. Lohman, Y. Li, V. L. Morgan, L. S. Rowles, T. Stephen, H.-Y. Shyu, R. A. Bair, C. J. Castro, R. D. Cusick, D. H. Yeh, and J. S. Guest. ACS Environ. Au 2023, 3 (4), 209–222.
In resource-limited settings, conventional sanitation systems often fail to meet their goals – with system failures stemming from a mismatch among community needs, constraints, and deployed technologies. This work introduces a multi-criteria decision analysis framework and the open-source tool DMsan for the sustainability analyses of sanitation and resource recovery technologies.
H. A. C. Lohman, V. L. Morgan, Y. Li, L. S. Rowles, X. Zhang, R. D. Cusick, S. M. Cook, and J. S. Guest. ACS Environ. Au 2023, 3 (3), 179–192.
21.
Design of a High-Rate Wastewater Treatment Process for Energy and Water Recovery at Biorefineries
This work introduces a high-rate, multistage anaerobic wastewater treatment process that has the potential to substantially improve the economic and environmental sustainability of biorefineries.
Y. Li, G. A. Kontos, D. V. Cabrera, N. M. Avila, T. W. Parkinson, M. B. Viswanathan, V. Singh, F. Altpeter, R. A. Labatut, and J. S. Guest. ACS Sustainable Chem. Eng. 2023, 11 (9), 3861–3872.
This study evaluates the influence of U.S. state-level tax incentives and economic parameters on cellulosic and conventional biofuel production costs.
D. W. Stewart, Y. R. Cortés-Peña, Y. Li, A. S. Stillwell, M. Khanna, and J. S. Guest. Environ. Sci. Technol. 2023, 57 (6), 2262–2271.
An engineered Saccharomyces cerevisiae capable of producing 2,3-butanediol (2,3-BDO) from glucose without accumulating ethanol and glycerol was constructed in this work. Techno-economic analysis (TEA) and life cycle assessment (LCA) of the production of methyl ethyl ketone (MEK) through catalytic dehydration of 2,3-BDO was performed and demonstrated the feasibility of cost-competitive and sustainable bio-based MEK production via yeast fermentation. Further, the fermentation broth containing 2,3-BDO was also tested in Arabidopsis thaliana for its potential to be used as a biostimulant, proving the broth could induce drought tolerance without a complicated purification process.
J. W. Lee, S. S. Bhagwat, N. Kuanyshev, Y. B. Cho, L. Sun, Y.-G. Lee, Y. R. Cortés-Peña, Y. Li, C. V. Rao, J. S. Guest, and Y.-S. Jin. Chem. Eng. J. 2023, 451, 138886.
2022
Research, development, and deployment (RD&D) of innovative technologies are often impeded by the lack of transparent, systematic, and agile approaches to prioritize investment across the expansive landscape of technologies and design/operational decisions. This tutorial review synthesizes research on sustainability analyses to present Quantitative Sustainable Design (QSD) – a structured methodology to expedite the RD&D of water, sanitation, and resource recovery technologies.
Y. Li, J. T. Trimmer, S. Hand, X. Zhang, K. G. Chambers, H. A. C. Lohman, R. Shi, D. M. Byrne, S. M. Cook, and J. S. Guest. Environ. Sci.: Water Res. Technol. 2022, 8 (11), 2439-2465.
In this study, the metal–organic framework (MOF) was applied as a precursor template to synthesize Co3O4 nanoparticles with a carbon matrix shell (M-Co3O4). The effects of catalyst dosage, methanol dosage, water dosage, temperature, and reaction time on catalytic efficiency were examined with stearic acid as the model reactant. Under the designed condition, M-Co3O4 exhibited high catalytic performance and the catalyst showed higher conversion of stearic acid (98.7%) and selectivity toward C8–C18 alkanes (92.2%) in comparison with Pt/C (95.8% conversion and 93.2% selectivity toward C8–C18). The catalysts were also characterized by a series of characterization techniques including electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), nitrogen adsorption isotherms (Brunauer–Emmett–Teller (BET) method), and thermogravimetric analysis (TGA). Finally, we proposed that decarbonization (deCO) could be the presumably mechanistic pathway for the production of C8–C18 alkanes from the decomposition of stearic acid.
D. Zeng, Y. Li, T. Xia, F. Cui, and J. Zhang. ACS Omega 2022, 7 (37), 33482–33490.
16.
Financial Viability and Environmental Sustainability of Fecal Sludge Treatment with Omni Processors
In this study, QSDsan was used to characterize the financial viability and environmental implications of fecal sludge treatment via pyrolysis-based omni processor technology (biogenic refinery) treating mixed and source-separated human excreta and to elucidate the key drivers of system sustainability.
L. S. Rowles, V. L. Morgan, Y. Li, X. Zhang, S. Watabe, T. Stephen, H. A. C. Lohman, D. DeSouza, J. Hallowell, R. D. Cusick, and J. S. Guest. ACS Environ. Au 2022, 2 (5), 455–466.
Robust and agile tools are needed to support the research, development, and deployment (RD&D) of sanitation and resource recovery technologies. This work introduces QSDsan – an open-source Python tool that integrates system design, simulation, and sustainability characterization (techno-economic analysis and life cycle assessment) to quickly identify critical barriers, prioritize research opportunities, and navigate multi-dimensional sustainability tradeoffs for technology RD&D.
Y. Li, X. Zhang, V. L. Morgan, H. A. C. Lohman, L. S. Rowles, S. Mittal, A. Kogler, W. A. Tarpeh, and J. S. Guest. Environ. Sci.: Water Res. Technol. 2022, 8 (10), 2289–2303.
2021
14.
Sustainable Production of Acrylic Acid via 3-Hydroxypropionic Acid from Lignocellulosic Biomass
Sustainable design of lignocellulosic 3-hydroxypropionic acid biorefineries producing acrylic acid, with agile techno-economic analysis and life cycle assessment under uncertainty.
S. S. Bhagwat, Y. Li, Y. R. Cortés-Peña, E. C. Brace, T. A. Martin, H. Zhao, and J. S. Guest. ACS Sustainable Chem. Eng. 2021, 9 (49), 16659–16669.
Deoxygenation of fatty acids to diesel-like hydrocarbons over Metal–Organic Framework (MOF)-derived metal oxides.
D. Zeng, Y. Li, H. Ma, F. Cui, and J. Zhang. ACS Sustainable Chem. Eng. 2021, 9 (46), 15612–15622.
12.
Vapor-Phase Catalytic Conversion of Aqueous 3-Hydroxybutyric Acid and Crotonic Acid to Propylene
Vapor-phase dehydration and decarboxylation of polyhydroxybutyrate-derived monomer acids (3-hydroxybutyric acid and crotonic acid) to propylene over solid acid catalysts using a packed-bed continuous-flow reactor for dilute waste carbon valorization.
S. Leow, A. J. Koehler, L. E. Cronmiller, X. Huo, G. D. Lahti, Y. Li, G. R. Hafenstine, D. R. Vardon, and T. J. Strathmann. Catal. Sci. Technol. 2021, 11 (20), 6866–6876.
Solids residence time can be leveraged as a selective pressure to tailor mixed phototrophic communities for wastewater nutrient removal and biofuel production.
I. M. Bradley, Y. Li, and J. S. Guest. Environ. Sci. Technol. 2021, 55 (18), 12574–12584.
10.
Catalytic Hydrothermal Deoxygenation of Lipids and Fatty Acids to Diesel-like Hydrocarbons: A Review
This reviews summarizes the reactions, catalysts, and influencing factors in the hydrothermal deoxygenation of lipids and fatty acids to diesel-like hydrocarbons.
X. Yao, T. J. Strathmann, Y. Li, L. E. Cronmiller, H. Ma, and J. Zhang. Green Chem. 2021, 23 (3), 1114–1129.
9.
Sustainable Lactic Acid Production from Lignocellulosic Biomass
Sustainable design of lignocellulosic biorefineries for lactic acid production with agile techno-economic analysis and life cycle assessment under uncertainty.
Y. Li, S. Bhagwat, Y. Cortés-Peña, D. Ki, C. V. Rao, Y.-S. Jin, and J. S. Guest. ACS Sustainable Chem. Eng. 2021, 9 (3), 1341–1351.
2020
This study shows that PFAS sorbed to sludge degrade to varying degrees when sludge is subjected to hydrothermal liquefaction for production of liquid fuel.
J. Yu, A. Nickerson, Y. Li, Y. Fang, and T. J. Strathmann. Environ. Sci.: Water Res. Technol. 2020, 6 (5), 1388–1399.
2019
Investigation of reaction mechanism and development of a kinetic network model for hydrothermal conversion of polyhydroxybutyrate (PHB) for wastewater valorization.
Y. Li and T. J. Strathmann. Green Chem. 2019, 21 (20), 5586–5597.
6.
Catalytic Hydrothermal Decarboxylation and Cracking of Fatty Acids and Lipids over Ru/C
Low-cost Ru catalysts can be applied to produce a mixture of alkanes, matching properties of existing petroleum diesel or jet fuel.
J. Zhang, X. Huo, Y. Li, and T. J. Strathmann. ACS Sustainable Chem. Eng. 2019, 7 (17), 14400–14410.
Evaluation of the treatment efficacy and economic performance of an algal wastewater treatment and valorization system across different seasons.
Y. Li, S. A. Slouka, S. M. Henkanatte-Gedera, N. Nirmalakhandan, and T. J. Strathmann. Environ. Sci.: Water Res. Technol. 2019, 5 (9), 1545–1557.
4.
Demonstration and Evaluation of Hybrid Microalgae Aqueous Conversion Systems for Biofuel Production
Experiments and model predictions show increased algal biofuel yields at lower prices via proposed hybrid conversion systems.
Y. Li, S. Leow, T. Dong, N. J. Nagle, E. P. Knoshaug, L. M. L., Laurens, P. T. Pienkos, J. S. Guest, and T. J. Strathmann. ACS Sustainable Chem. Eng. 2019, 7 (6), 5835-5844.
2018
3.
A Unified Modeling Framework to Advance Biofuel Production from Microalgae
Integrating biological cultivation model with thermochemical/biological unit process models to increase modeling fidelity, provide mechanistic links among unit operations, and quantify minimum selling prices of algal biofuels via techno-economic analysis.
S. Leow, B. D. Shoener, Y. Li, J. L. DeBellis, J. Markham, R. Davis, L. M. L. Laurens, P. T. Pienkos, S. M. Cook, T. J. Strathmann, and J. S. Guest. Environ. Sci. Technol. 2018, 52 (22), 13591-13599.
Design, demonstration, and economic anlaysis of an aqueous-based system for the conversion of wastewater-derived algae and upgrading of crude products.
Y. Li, W. A. Tarpeh, K. L. Nelson, and T. J. Strathmann. Environ. Sci. Technol. 2018, 52 (21), 12717-12727.
2017
1.
Quantitative Multiphase Model for Hydrothermal Liquefaction of Algal Biomass
A multiphase component additivity (MCA) model to quantitatively predict both yields and characteristics of products from hydrothermal liquefaction of microalgae.
Y. Li, S. Leow, A. C. Fedders, B. K. Sharma, J. S. Guest, and T. J. Strathmann. Green Chem. 2017, 19 (4), 1163-1174.
Public Media
Y. Li., The Conversation, 2019.
Presentations
Select conference presentations.
2022
24.
Y. Li and J. S. Guest. Research Prioritization and Systems-Level Optimization: Advancing Precision Fermentation in an Urban Context (Invited Talk). Precision Fermentation and Sustainability: Urban Solutions for Singapore, Singapore/Online, September 16, 2022.
23.
J. S. Guest, D. M. Byrne, S.M. Cook, R. D. Cusick, Y. Li, W. A. Tarpeh. Introducing Quantitative Sustainable Design (QSD) as a Structured Approach for Research and Education (Workshop). AEESP Research and Education Conference, St. Louis, MO, United States, June 28-30, 2022. Workshop materials.
22.
Y. Li, X. Zhang, V. L. Morgan, H. A. C. Lohman. The QSDsan Platform: Open-Source Tools for Quantitative Sustainable Design and Decision-Making of Sanitation and Resource Recovery Technologies (Workshop). 27th Environmental Engineering and Science Symposium, Urbana, IL, United States, April 22, 2022. YouTube link; workshop materials.
2021
21.
Y. Li, X. Zhang, L. S. Rowles, V. L. Morgan, H. A. C. Lohman, S. Mittal, A. Kogler, S. E. Aguiar, W. A. Tarpeh, R. D. Cusick, J. S. Guest. An Integrated Platform for Quantitative Sustainable Design of Sanitation and Resource Recovery Systems under Uncertainty (Poster). IWA Water Resources Recovery Modelling Conference (Virtual), August 21-25, 2021.
20.
Y. Li, G. A. Kontos, N. Avila, D. V. Cabrera, M. Viswanathan, V. Singh, R. A. Labatut, and J. S. Guest. Design of a Small-footprint Wastewater Treatment and Energy Recovery Process for Biorefineries. International Conference on Resource Sustainability (Virtual), July 19-23, 2021.
19.
Y. Li. Advancing the Sustainability of Engineered Systems through Experimentation and Quantitative Sustainable Design (QSD) (Invited talk). AEESP AJAR Future Faculty Seminar Series (Virtual). March 12, 2021. YouTube link.
2020
18.
Y. Li, S. S. Bhagwat, Y. Cortes-Peña, D. Ki, C. V. Rao, Y.-S. Jin, and J. S. Guest, Sustainable Lactic Acid Production from Lignocellulosic Biomass. 2nd Bioenergy Sustainability Conference (Virtual), October 13-15, 2020.
17.
Y. Li, S. S. Bhagwat, Y. Cortes-Peña, D. Ki, C. V. Rao, Y.-S. Jin, and J. S. Guest, Evaluating the Sustainability of Lactic Acid Production from Lignocellulosic Biomass. ACS Fall 2020 Virtual Meeting & Expo, August 17-20, 2020.
2019
16.
Y. Li and J.S. Guest. Navigating Tradeoffs in Design of Pretreatment Strategies for Lignocellulosic Biomass of Varying Composition. Bioenergy Sustainability Conference, Nashville, TN, United States, October 21-22, 2019.
15.
Y. Li, S. Leow, T. Dong, L.M.L. Laurens, P.T. Pienkos, J.S. Guest, and T.J. Strathmann. Demonstration and Evaluation of Integrated Microalgae Systems for Biofuel Production (Invited talk for Gonter Award). 258th ACS National Meeting & Exposition, San Diego, CA, United States, August 25-29, 2019.
14.
Y. Li, D. R. Vardon, and T. J. Strathmann. Advancing Resource Recovery from Wastewater: Part 2 – Hydrothermal Conversion of Polyhydroxybutyrate (PHB)-Containing Biomass (Poster). AEESP Research and Education Conference, Arizona State University, Tempe, AZ, United States, May 14-16, 2019.
13.
Y. Li, S. Leow, W. A. Tarpeh, T. Dong, N. J. Nagle, E. P. Knoshaug, L. M. L. Laurens, P. Tienkos, K. L. Nelson, J. S. Guest, and T. J. Strathmann (Poster). Advancing Resource Recovery from Wastewater: Part 1 – Aqueous Conversion Processes for Algal Biomass. AEESP Research and Education Conference, Arizona State University, Tempe, AZ, United States, May 14-16, 2019.
2018
12.
Y. Li, S. Leow, T. Dong, L. M. L. Laurens, P. T. Pienkos, J. S. Guest, and T. J. Strathmann. Demonstration and Evaluation of Integrated Microalgae Systems for Biofuel Production (Oral and poster). 256th ACS National Meeting & Exposition, Boston, MA, United States, August 19-23, 2018.
11.
Y. Li, W. Tarpeh, K. L. Nelson, and T. J. Strathmann. Complete Valorization of Wastewater Algae via an Integrated Thermo- and Electrochemical Processing Strategy (Oral). 256th ACS National Meeting & Exposition, Boston, MA, United States, August 19-23, 2018.
10.
Y. Li, W. Tarpeh, K. L. Nelson, and T. J. Strathmann. Energy and Nutrient Recovery from Hydrothermal Process Co-products (Oral). 256th ACS National Meeting & Exposition, Boston, MA, United States, August 19-23, 2018.
9.
Y. Li, S. A. Slouka, S. M. Henkanatte-Gedera, N. Nirmalakhandan, W. A. Tarpeh, K. L. Nelson, and T. J. Strathmann. Re-inventing Wastewater Treatment Systems (Student spotlight oral presentation). 2018 ReNUWIt Annual Meeting, Stanford, CA, United States, May 23, 2018.
8.
Y. Li, S. A. Slouka, S. M. Henkanatte-Gedera, N. Nirmalakhandan, W. A. Tarpeh, K. L. Nelson, and T. J. Strathmann. Transformation of Wastewater Treatment: Energy and Nutrient Recovery from Municipal Wastewater (Oral). 15th RMSAWWA/RMWEA Joint Student Conference, Golden, CO, United States, May 14, 2018.
2017
7.
Y. Li, T. J. Strathmann, S. Leow, N. Nirmalakhandan, W. A. Tarpeh, J. S. Guest, and D. R. Vardon. Integrated Bio-Hydrothermal-Catalytic Pathways for Optimum Conversion of Algal Biomass and Wastewater Biosolids to Liquid Transportation Fuels (Invited talk). 9th National Conference on Environmental Chemistry, Hangzhou, China, October 19-22, 2017.
6.
Y. Li, S. A. Slouka, S. M. Henkanatte-Gedera, N. Nirmalakhandan, and T. J. Strathmann. Transformation of Wastewater Treatment – Energy and Nutrient Recovery from Municipal Wastewater (Oral). Student Paper Night of Colorado Scientific Society, Golden, CO, United States, September 21, 2017.
5.
Y. Li, S. Leow, A. C. Fedders, J. S. Guest, and T. J. Strathmann. Quantitative Evaluation of Hydrothermal Liquefaction for Algal Biomass Valorization (Poster). AEESP Research and Education Conference, Ann Arbor, MI, United States, June 20-22, 2017.
4.
Y. Li, S. Leow, J. S. Guest, and T. J. Strathmann. Hydrothermal Liquefaction for Biomass Valorization (Invited talk). ENN Group, Langfang, Hebei, China, February 7, 2017.
2016
3.
Y. Li, S. Leow, A. C. Fedders, B. K. Sharma, J. S. Guest, T. Dong, N. J. Nagle, P. T. Pienkos, and T. J. Strathmann. A Comprehensive Model for Hydrothermal Liquefaction (HTL) of Microalgae (Oral and Poster). 10th Algae Biomass Summit, Phoenix, Arizona, United States, October 23-26, 2016.
2.
Y. Li, S. Leow, A. C. Fedders, B. K. Sharma, J. S. Guest, T. Dong, N. J. Nagle, P. T. Pienkos, and T. J. Strathmann. Quantitative prediction of microalgae hydrothermal liquefaction (Oral). 252nd American Chemical Society (ACS) National Meeting & Exposition, Philadelphia, PA, United States, August 21-25, 2016.
1.
Y. Li, S. Leow, J. S. Guest, and T. J. Strathmann. A Quantitative Multiphase Component Additivity Model for Hydrothermal Liquefaction of Microalgae (Poster). STREAM (Skills, Technology, Research and Management) Challenge Week, Torquay, UK, July 10-15, 2016.