Paul Anastas's picture Paul Anastas, Ph.D.

Teresa and H. John Heinz III Professor in the Practice of Chemistry for the Environment

Paul T. Anastas is the Teresa and H. John Heinz III Professor in the Practice of Chemistry for the Environment. He has appointments  in the School of the Environment, Department of Chemistry, and Department of Chemical Engineering. In addition, Prof. Anastas serves as the Director of the Center for Green Chemistry and Green Engineering at Yale.

Deputy Director
Julie B. Zimmerman's picture Julie B. Zimmerman, Ph.D.

Deputy Director

Senior Associate Dean of Academic Affairs

Professor in School of Engineering & Applied Science
Professor in School of the Environment

Senior Staff
Karolina Mellor's picture Karolina Mellor, Ph.D.

Program Director

The Global Green Chemistry Innovation and Network Program

- Karolina oversees all education, outreach and international partnerships at the Center. Before coming to Yale in 2014, Karolina received her Ph.D. in molecular biology from the University of Virginia. She also worked at the University Innovation Licensing and Ventures Group where she evaluated patent strategies and explored commercial potential of technologies developed at the university. Now, Dr. Mellor oversees the Yale-UNIDO collaboration that brings green chemistry to practitioners in emerging economies around the globe.  She works with industry, academia and governments to advance dissemination green chemistry and sustainability.

- Outside of the lab, Karolina is an avid runner, salsa dancer and a foodie. She also loves sci-fi and fantasy in any shape or form.


Hanno Erythropel's picture Hanno Erythropel, Ph.D.

Associate Research Scientist

- Hanno supports the oversight of research at the Center. He is passionate about building interdisciplinary bridges between chemistry, chemical engineering, material science, toxicology, and other disciplines to create green chemistry solutions using a systems thinking framework. His work has focused on valorizing different types of biomass, developing highly functional yet biodegradable and non-toxic materials such as plasticizers, and better understanding the composition and content of tobacco products.

- Outside of the lab, Hanno enjoys exploring new places and countries and learning about local language and culture. Hanno is also an avid bike-rider.


Yuan Yao's picture Yuan Yao, Ph.D.

Assistant Professor of Industrial Ecology and Sustainable Systems

Dr. Yao's research is motivated by the increasing need for sustainable solutions that can support industrial development without compromising the environment or depleting the resources for future generations. Her research investigates how emerging technologies and industrial development will affect the environment. She uses interdisciplinary approaches in industrial ecology, sustainable engineering, and machine learning to develop systems analysis tools to support engineering and policy decisions towards sustainability. She develops new methods and integrated modeling frameworks to assess, advance, and optimize industrial systems for improved environmental and societal outcomes.

Darren S. Lee's picture Darren S. Lee, Ph.D.

Associate Research Scientist

- Darren’s research interests lie at the interface of synthesis, flow chemistry and engineering. With a background in organic synthesis, he soon developed an interest in using technology and engineering to explore chemistries that are underutilized at large scales. He has been involved in developing novel reactor designs for photochemistry and electrochemistry. He arrived at Yale in 2022 and is developing green chemical processes using continuous flow technology.

- Outside of the lab Darren enjoys spending time with his family and friends. He is also a keen cook, enjoys reading and going on long walks to explore nature and wildlife.


Nicole Deziel's picture Nicole Deziel, Ph.D.

Assistant Professor of Epidemiology (Environmental Health Sciences) and Chemical and Environmental Engineering

Dr. Deziel obtained a Master’s of Industrial Hygiene and Doctorate in Environmental Health from the Johns Hopkins Bloomberg School of Public Health. Her research involves applying statistical models, biomonitoring techniques, and environmental measurements to provide comprehensive and quantitative assessments of exposure to combinations of traditional and emerging environmental contaminants. Her exposure assessment strategies aim to reduce exposure misclassification for epidemiologic studies, advancing understanding of relationships between of exposure to environmental chemicals and risk of cancer and other adverse health outcomes.

Brooke DeRosa

Program & Financial Administrator

-Brooke provides finance and budgeting support to the UNIDO project. Her prior experience includes public accounting audits of manufacturing and service sector clients, and management of financial reporting and development of budgets in the hospitality industry.

-Her interests include sourdough bread baking, outdoor activities like tennis and gardening, and volunteer work with individuals experiencing food insecurity.


Predrag Petrovic's picture Predrag Petrovic, Ph.D.

Associate Research Scientist

- Predrag obtained a Ph.D. degree in organometallic chemistry by applying experimental and theoretical approaches to studying non-covalent interactions in organometallic complexes. In 2017 he joined the Center where his main research focus is setting a foundation for the methodology that will help safer chemical design that complies with the 12 Principles of Green Chemistry by using various computational tools (DFT, ab initio, etc.).

- In his free time, Predrag loves reading sci-fi and fantasy books, riding a bike, taking long walks and (not-so-long) hikes, and very occasionally playing video games .

Krystal Pollitt's picture Krystal Pollitt, Ph.D.

Assistant Professor of Epidemiology (Environmental Health Sciences) and Chemical and Environmental Engineering

Dr. Pollitt’s research explores the human exposome through characterisation of environmental and biological samples using analytical and mass spectrometry (MS) techniques. Her group has developed various mass spectrometry (ICP-MS, LC-MS and GC-MS) to measure exposure to complex mixtures of trace elements and organic compounds. She has applied these exposure assessment methods in numerous in epidemiological studies.

Lars Ratjen's picture Lars Ratjen, Ph.D.

Associate Research Scientist

- Lars likes changing places and learning things from nature and people. Before coming to Yale in 2022 he spent almost 9 years in Chile, working for Fraunhofer, at the interface of academia and industry. He is focused on interdisciplinary projects, ranging from chemistry over engineering to environmental health. He is also involved in helping other countries in sustainable development in the Yale-UNIDO initiative, which he is very passionate about.

- Out of the lab Lars enjoys watersports, cooking and trying new food, reading pretty much anything and he is an occasional artisan. There are (almost) no animals he does not like.

Research Staff
Elise Gilcher, Ph.D. (she/her)

Postdoctoral Associate

- Elise received her PhD from the University of Wisconsin-Madison studying heterogeneous catalysis, biomass degradation and chemical conversion of products towards useful platform molecules. Her research interests and current projects at the Center focus on green solutions for sustainable extraction and chemical conversion of algae biomass to high value products that further an initiative towards a robust bioeconomy.

- Elise enjoys time outside gardening, running, and exploring the CT forests, lakes, and coastline. She also loves cooking and creating experimental, innovative recipes.

Heather LeClerc's picture Heather LeClerc, PhD (she/hers)

Donnelley Post-Doctoral Fellow

- Heather received her PhD studying the molecular degradation (and repolymerization) pathways of waste to energy in hydrothermal systems. Her work at Yale will focus on transferring these skills towards understanding the complexities of lignin valorization in continuous flow systems. Her research interests span the realm of sustainable waste utilization and using analytical techniques as puzzle pieces to reveal chemical mechanisms.

- Outside of the lab, Heather loves to play with her dog Stanley and go on walks on the Farmington Canal train. She also loves traveling and has been to over 30 countries!


Tetyana Budnyak's picture Tetyana Budnyak, , PhD (She/Her)

Research Fellow

Tetyana Budnyak's research endeavors revolve around developing functional materials for environmental applications. Her primary focus lies in finding green solutions to valorize biopolymers, thereby producing value-added materials for promoting water purification. An ongoing joint project between the Center for Green Chemistry and Green Engineering and Uppsala University is dedicated to developing green lignin-biochar composites capable of removing organic and inorganic pollutants from water. 

Elena Subbotina, Ph.D.

Postdoctoral Associate

- During my PhD studies at the department of organic chemistry at Stockholm University my work was focused on the production and transformation of organic compounds from lignin via catalytic approaches. After the graduation I joined the group of Prof. Lars Berglund at KTH, where I expanded my research interests to include nanocellulose based materials. Currently, as a postdoctoral fellow at the Center for Green Chemistry & Green Engineering at Yale, I am involved in a project where we aim to develop novel recyclable materials from bio-based building blocks.

- Outside of the lab, Elena enjoys making chemical reactions and publishing papers in Nature Chemistry for leisure.

Hannah Feldman, (she/her)

Program Coordinator

- Hannah will provide administrative, clerical, and program support to the Center, specifically the Yale-UNIDO project (Global GreenChem Innovation and Network Programme). She has a background in environmental history, with a specific interest in energy and climate change. She wrote her Master's thesis on the 1970s energy crisis and the use of alternative energy sources. Previously, Hannah also worked at Rutgers University.

- Outside of work, Hannah loves reading books and listening to (and playing) music of all types. You can probably find her somewhere with headphones on.


Ho Yin TSE's picture Ho Yin TSE, Ph.D. (He/His)

Postdoctoral Associate


-Leo’s research focuses primarily on the sustainable photonic functional materials development, with a particular emphasis on the fabrication of new lignin-based photo-responsive nanoparticles and their fundamental photo-physics studies. During his Ph.D. training, he also involved in a numerous of professional consultation projects, including biotechnology assisted food-waste upcycling, energy and elements recovery from wastewater treatment processes and urban biorefinery engineering, etc. Currently, he is further developing new bio-based photonic materials and carbon sequestration processes at the Center.

-Outside of the lab, Leo enjoys driving, watching movies and documentaries on science & philosophy discussion.


Avery Long's picture Avery Long, (he/him)

Undergraduate Research Assistant

- Avery is studying the functionalization of gold nanoparticles; specifically, investigating whether particle anisotropy leads to increased sensitivity in glutathione-based Pb2+ detectors. Broadly, he hopes to apply chemistry to the development of sustainable materials and processes. He is currently most interested in functional materials, agricultural chemistry, and their interface, but this changes depending on what classes he is currently enjoying most.   

- When he isn't in lab, Avery is either teaching his friends how to ballroom dance, chipping away at his endless reading list, or talking about his home state of Michigan.

Andreas Backhaus's picture Andreas Backhaus, (he/him/his)

Ph.D. Candidate in Chemical and Environmental Engineering

- Andreas joined the Zimmerman lab as a graduate student at the Center for Green Chemistry & Green Engineering at Yale in 2019. He develops flow chemistry and multiplexed synthesis approaches for sustainable and scalable nanomanufacturing and the accelerated parameter space exploration for nanomaterial syntheses. Andreas worked in industrial chemical process development before, obtaining a master’s degree in Environmental Process Engineering and a master’s degree in General Management from RWTH Aachen University.

- Outside of the lab, Andreas competes in breaking (breakdancing).


Holly Rudel's picture Holly Rudel

PhD Candidate in Chemical & Environmental Engineering

- Holly is interested in utilizing a fundamental chemical understanding to design sustainable drinking water treatment technologies. She is particularly motivated to leverage the power of science to benefit society, both people and the environment. After graduating from Bowdoin with a degree in chemical physics and participating in a post-graduate teaching fellowship, Holly joined Yale in 2018 and is excited to share her love and curiosity with aspiring scientists and engineers.

- Outside of the lab, Holly can most likely be found hanging out with her cat, Periwinkle, or swimming laps at the pool.

Cheldina Jean's picture Cheldina Jean, (she/her)

PhD student

- Cheldina is interested in sustainable materials for water treatment in the developing world. After graduating from American University and partaking in individual research opportunities, she arrived at Yale in 2020. She is developing methods to improve the performance of point-of-use ceramic water filters. 

- Outside of lab Cheldina loves to read, exercise, and explore New Haven with her friends.


Fredrika Aakerman, (she/her)

Undergraduate Research Assistant

- Fredrika is interested in the energy and material transition away from petrochemical sources and the application of environmental science to the design of products and processes in line with human and planetary health. During her exchange semester at Yale, she took Fundamentals of Green Chemistry and Green Engineering with Professor Paul Anastas and Dr Hanno Erythropel and joined the Center over the summer to gain practical experience in applying sustainability principles to chemical design.

- When not in the lab, Fredrika likes joining her friends on unplanned trips and capturing the travels on film. She also likes practicing yoga, reading historical fiction, and making themed playlists.

Dylan Judd, (he/him/his)

PhD Student at the Yale School of the Environment

PhD Student at the Yale School of the Environment

-Dylan is interested in promoting sustainable advances at every stage of materials science, ranging from the utilization of flow chemistry in synthesis efforts to the equitable implementation and associated impacts of climate-centered technologies. Dylan received both his B.A. in Chemistry and Environmental Studies and his M.A. in Chemistry from Wesleyan University while conducting research on plasmon-mediated nanoparticle production and reconfiguration. Dylan joined the Center for Green Chemistry & Green Engineering at Yale in 2023 with the hope that he can use his interdisciplinary perspective to bring novel insights to the variety of research questions with which the Center is concerned.

-Outside of the lab, Dylan loves to read, do crossword puzzles, and play sports, such as baseball and volleyball. You may also find him listening to all types of music on his turntable or over his headphones.


Fang Lin's picture Fang Lin

PhD candidate in the Department of Chemistry

- Fang was awarded the ACS outstanding graduating senior upon graduation from SUNY Binghamton. Her research focuses on converting renewable feedstocks such as lignin into value-added chemicals using a sustainable strategy- electrochemistry. Her work spans from fundamental (mechanistic studies of bond cleavage chemistry) to applied science (lignin valorization) by utilizing various instrumentations. She also did plenty of organic synthesis for molecular analogs and lignin dimers for modeling studies.

- Outside of the lab, Fang is a foodie, likes cooking and exploring different types of restaurants around. She is also an outdoor enthusiast, enjoys snorkeling, hiking, and skydiving.

Emily Johnson's picture Emily Johnson, (she/her)

PhD Student at Yale School of Public Health

- Emily is interested in the intersection between green chemistry and public health. After completing her BS, she moved into the world of public health, where she studies personal exposures to air pollutants. Working under Dr. Krystal Pollitt, she focuses on capturing airborne PFAS exposures using the Fresh Air passive air samplers. While completing her MPH, she learned about the fundamentals of green chemistry, and she intends to merge her environmental health science background into design-phase research and the fields of green chemistry and engineering. During her PhD, she hopes to continue this work in the studies of microplastics as well as the interface between disease and chemical contaminants.  

- Outside of the lab, Emily loves to read, drink too much coffee, listen to music, and hang out with her dog, Darcie.

Mary Kate Mitchell Lane's picture Mary Kate Mitchell Lane, (she/her/hers)

PhD Candidate in Chemical and Environmental Engineering, NSF and ACS Fellow

- Mary Kate’s research utilizes supercritical fluids as green solvents for biorefinery and nanoparticle synthesis applications. Prior to graduate school, Mary Kate gained experience in a diverse set of industry and research roles (interning in oil refining and natural gas distribution; research in ultracapacitor development, biofuel synthesis, and water treatment) that motivated her to pursue a research career focused on green chemistry and sustainability.

- Outside of the lab, Mary Kate applies Green Chemistry to increase inclusion. She led the publication of the recent literature review, “What to Expect When Expecting in Lab”

Greg Sieczkiewicz's picture Greg Sieczkiewicz, Ph.D., J.D. (he/his)

PhD Student at the Yale School of the Environment

- Grey is a seasoned biotechnologist with over two decades of experience as a researcher, patent attorney, entrepreneur, and inventor. He seeks to drive sustainable innovation with commercial applicability and global impact. His research uses systems theory to integrate data from a molecular/biochemical level to an organismal/ecological scale.

- Grey enjoys running, cycling, hiking, and spending time with his partner, four children, and German short-haired pointer. Always an optimist, he loves a challenge.


Jaye Wilson, (she/her)

PhD Student at the Yale School of Environment

- Jaye is a National Science Foundation Graduate Research Fellow translating her love for fashion, organic, and polymeric chemistry into the Environment. While environmental justice and STEM equity sit at the forefront of all her endeavors, Jaye’s academic activism path focuses specifically on developments and policies that create sustainable materials and recycling systems to address the plastics pollution in the textile industry.

- When Jaye is not in the lab, you can find her at a farmers’ market, baking, picnicking with friends, or taking pictures in her second-hand outfits.

Momoko Ishii

PhD Student at the Department of Chemical & Environmental Engineering and School of the Environment

- Momoko is interested in carbon dioxide as a building block in flow synthesis.

Jessie Wainer

MSc Student

- Jessie’s current research is focused on sustainable water treatment. She is interested in how waste materials and by-products can be repurposed for valuable applications such as removing dangerous contaminants from water. Prior to Yale, she worked at the University of the Witwatersrand in South Africa investigating methods of extracting valuable minerals from waste materials, in particular gold tailings and coal fly ash.

- Jessie enjoys swimming and climbing and has always been an avid fan of Survivor.

Allen Shi's picture Allen Shi, MSc, PhD candidate (he/him)

Visiting PhD Student

-Allen is interested in reusing waste materials (biomass or municipal waste) for profitable purposes as well as contributing to the fixation of carbon in materials for a sustainable circular economy. Prior to joining Yale, he was a PhD student at the Chinese University of Hong Kong, where he developed an ecologically friendly method for manufacturing porous materials using Pickering foam templates. He obtained a master's degree in Polymer, Colorants, and Fine Chemicals from the University of Leeds and spent over three years developing non-solvent adhesive products for BASF.

-Outside of the lab, Allen loves traveling and reading to gain insight into other cultures and people around the world. He also enjoys outdoor activities (e.g. swimming, hiking, golfing, and wakesurfing).


Tobias Muellers, (he/him)

Post-Graduate Researcher

- Tobias is interested in the intersection of toxicology and chemistry, as well as advancing safer chemical design. Within the Center, he utilizes computational chemistry and statistical techniques to enable the rational design of safer chemicals. Prior to Yale, he dabbled in analytical and synthetic chemistry and worked as an environmental chemist conducting chemical hazard assessments.

- Tobias loves spending time in nature for just about any reason (e.g., hiking, biking, running, canoeing), cooking and baking, and reading.