U of T Engineering researchers have discovered a new way of capturing carbon directly from the air — one that could offer significant cost savings over current methods.
The team calls their new technique evaporative carbonate crystallization. Because it is powered by passive processes such as capillary action and evaporation, it has the potential to eliminate some of the costliest steps required by existing carbon capture methods.
“We’ve had the technology to capture carbon dioxide (CO2) from flue gases, or even directly from the air, for decades now,” says Professor David Sinton (MIE), Interim Director of U of T’s Lawson Climate Institute and senior author on a paper published in Nature Chemical Engineering that describes the new technique.
“There are even some full-scale plants in operation, but the criticism that the industry always gets — with justification — it that it’s still just too expensive. So, we’ve oriented our team’s approach around radical cost reductions, and that is what this new method of evaporative carbonate crystallization is all about.”
Postdoctoral fellow Dongha Kim (MIE) is the lead author on the new paper. He says that he was strongly motivated by a desire to simplify current state-of-the-art carbon capture systems.
“One way to capture carbon is to use a strongly alkaline liquid, for example, a solution of potassium hydroxide. When air makes contact with this liquid, the carbon dioxide in the air reacts to become dissolved potassium carbonate,” says Kim.
“To speed up the reaction rate, you want to maximize the contact between the air and the liquid. In today’s most advanced systems, this is done by increasing surface area: a thin layer of the liquid is flowed over a porous solid support material, with a honeycomb-shaped structure. Giant fans or blowers are used to push air across this thin liquid layer at about 1.5 metres per second.”
Kim says that in many places in the world, prevailing winds are already faster than that: globally, the average is about 3 metres per second. This led him to think about ways to leverage those existing winds via a more passive system.
The design he came up with uses long strands of polypropylene fibre — essentially string. One end of the string is immersed in a solution of potassium hydroxide, which is slowly wicked up into the fibres.
When wind blows across the surface of the string, it evaporates the water in the solution, concentrating the dissolved potassium hydroxide to extremely high levels. That’s where the advantages of this system come into play.
“Because we have a very thin layer of extremely concentrated potassium hydroxide, the rate at which it reacts with carbon dioxide speeds way up,” says Kim.
“We can capture carbon at a much higher rate than with the more dilute solutions used in today’s systems. On top of that, the potassium carbonate salt that we produce doesn’t stay dissolved in solution — instead it forms a solid crystal right on the surface of the fibres.”
The result looks a bit like rock candy, which can be made from highly concentrated sugar solutions via a similar evaporative process. The fact that the carbon is captured in this solid form leads to another advantage.
“In conventional systems, you need some way to remove the dissolved carbonate from the capture liquid so you can use it again,” says Kim.
“Typically, this is done by adding other chemicals, such as calcium, to create a non-soluble salt, which you then have to filter out.”
“But because we have this highly concentrated solution generated by passive evaporation, we can go straight to the salt. We don’t need to add calcium, and we don’t need to filter it out; instead we can just wash it off with water, producing a highly-concentrated potassium carbonate solution.”
From here, an electrochemical process converts the potassium carbonate salts back into pure CO2 gas while simultaneously regenerating the potassium hydroxide, which can be reused. The CO2 gas can be stored, injected into underground wells or further processed into carbon-based fuels and chemicals such as methanol, ethanol, ethylene, etc.
In the paper, the team carried out a techno-economic analysis to evaluate how cost-competitive the new system might be if scaled up to industrial levels. They found that while the operating costs were similar to existing systems, the capital costs could be reduced by up to 40%.
“If you tour an industrial-scale carbon capture plant, the two biggest things you’ll see are the air contactor, with the fans and blowers, and the chemical plant used to regenerate the capture liquid,” says Sinton.
“If you can eliminate both of those, you can save a lot of money.”
There are still hurdles to be overcome. One is humidity: Kim says that the process is more efficient in dry air, rendering it more suitable for some environments than others. And more challenges may arise as the team works to build a pilot-scale plant to further validate the technology.
Still, the team feels that the current study demonstrates proof-of-concept, and that further refinements could continue to enhance its economic feasibility.
“It’s hard to predict the ultimate cost, but what we do know for certain is that polypropylene fibres are already cheap and plentiful, and that passive processes are inherently simpler and less costly than active ones,” says Sinton.
“Combine that with the scientific surprise, which is that our system creates a very thin layer of a super-concentrated solution that kicks the carbon-capture reaction into a higher gear, and it all adds up to a very promising approach.”
A reception held November 20 at the new U of T Engineering Partnerships Office at 800 Bay St. celebrated the past, present and future of collaboration between the University of Toronto and its partners in industry, government and the non-profit sector.
More than 200 guests attended the event, which was co-hosted by the Engineering Partnerships Office, the university-wide Blue Door partnerships office and Toronto Global. Presenters included Adriano Vissa, Executive Director of Partnerships at U of T Engineering, Professor Alex Mihailidis (BME), U of T’s Associate Vice-President of International Partnerships and Daniel Hengeveld, Toronto Global’s VP of Investment Attraction.
The unique space at 800 Bay St. provides companies with opportunities for flexible co-location and collaboration that put companies closer to the innovation and talent driving future-forward solutions. More than half a dozen different entities, including the AGE-WELL network and several companies launched by U of T Engineering alumni, call the space home.
“What we’ve seen over the past year are the incredible opportunities that co-location can open up, both for us as a research-intensive university and for our partners,” says Vissa.
“Whenever you put smart, talented people in a room together, you can’t help but spark new ideas, new ventures and new business models. Tonight is a time to celebrate our track record of success in doing that, and to catalyze even more of those types of collaborations for the future.”
Volunteers are at the very center of the university community, generously donating their time and insights to everything from mentorship, speaking, governance and student clubs. The Arbor Awards are the University of Toronto’s highest recognition for exceptional, long-standing volunteer service.
“Our volunteers are the heartbeat of our university community. They share their expertise, open doors for students and strengthen the connections that make us who we are. Their impact is felt every day — simply put, we couldn’t do this without them,” says Shannon Osborne (IndE 0T6), Manager of Alumni Relations at U of T Engineering.
Established in 1989, the Arbor Awards honour alumni and friends whose loyalty and dedication have significantly enriched the U of T experience.
Among this year’s 11 U of T Engineering recipients is Eva Lau (IndE 9T2). Lau has mentored hundreds of student-entrepreneurs at Rotman and U of T Engineering and is a champion for Canadian innovation. She also generously shares her time and expertise as a volunteer, guest speaker and panellist for multiple faculties at the university and serves as a member of the Defy Gravity Campaign Steering Committee.
“Our volunteers are catalysts for change. By sharing their knowledge and networks, they empower students, strengthen partnerships and help shape a bold, thriving future for our community,” says Osborne.
The 2025 U of T Engineering Arbor Award recipients include:
Liane Catalfo (ChemE 0T9, MEng 1T0)
Catalfo’s volunteer leadership with U of T Engineering has strengthened student and alumni engagement and advanced the faculty’s strategic goals. Her roles include membership on the Engineering Alumni Network Board, including a term as president, as well as representing alumni on the executive committee of Faculty Council and at the U of T Alumni Association Council of Presidents. Catalfo has also made a guest appearance on Tell Me More: Coffee With Chris Yip, the official podcast of U of T Engineering.
Oluwatobi Edun (ChemE 1T8)
As an engineering alumnus, Edun has participated in a rich variety of volunteer activities at U of T. In 2020, he took part in a program whereby alumni send encouraging notes to current students. Since then, Edun has stepped up in other ways, including as a mentor to students, serving as a speaker and panellist at events and helping to judge competitions. Most recently, he joined U of T Engineering’s Faculty Council, a key governing body.
Joelle Javier (MSE 1T0)
Javier has left an indelible mark on U of T Engineering and its students of the past, present and future. As an alumni assessor, Javier has evaluated applications from aspiring students. For currents students, she has generously delivered guest lectures about her work in amusement park safety. For alumni, Javier has rallied her peers for reunion events as a class ambassador and helped roll out a revamped awards program as chair of the Engineering Alumni Network Awards Committee. She appeared on Tell Me More: Coffee With Chris Yip In 2022.
Andrew L. Kidd (EngSci 1T9)
Kidd’s enthusiasm for U of T Engineering has continued unabated since his graduation. His enthusiasm for students and the curriculum is evident in his volunteerism, which includes engaging with undergraduate students in seminar courses, helping select recipients for scholarships and research awards, and sharing his experience as a mentor. Kidd’s additional contributions include serving as an alumni representative on Faculty Council and providing opportunities for students by helping his firm organize recruitment events.
Eva Lau (IndE 9T2)
Lau has contributed greatly to U of T and its thriving innovation ecosystem. A prominent venture capitalist, Lau has mentored hundreds of student-entrepreneurs at the Rotman School’s Creative Destruction Lab and The Hatchery at U of T Engineering. She has also generously shared her expertise as a volunteer, guest speaker and panellist for Massey College, Rotman and Engineering. More broadly, Lau supports the university’s top priorities as a member of the Defy Gravity Campaign Steering Committee. She was a guest on Tell Me More: Coffee With Chris Yip in 2024.
Sanjay Malaviya
Malaviya has been a diligent and generous champion for the Faculty of Applied Science & Engineering for over ten years. He has made major contributions to the evolution of engineering leadership education, which integrates complementary skillsets in leadership, communications, business, entrepreneurship and other areas. Malaviya has contributed countless hours and wise counsel, as well as significant financial support, and has served as a model of engineering leadership through his personal, inspiring example.
Pino Mancina (CivE 9T3)
Mancina has played an integral part in shaping the Engineering Alumni Applicant Assessor program. Now in its 11th year, the program engages engineering alumni to help assess applicants to the undergraduate program. Mancina has volunteered for eight years, dedicating countless hours to helping improve the program, with astute, ongoing feedback that has enhanced the admissions assessment process for U of T Engineering as well as the volunteer experience that the program provides for alumni.
M.G. Venkatesh Mannar
Mannar has been a dedicated supporter of the Department of Chemical Engineering & Applied Science for some 30 years. In his current role as adjunct professor, he mentors students and regularly participates in research meetings and thesis committees. He also promotes the department’s research findings to his high-profile international network. Further, Mannar has been integral to U of T’s work in fortifying salt with iodine, iron, vitamins and zinc helping reduce anemia and a range of health disorders in women and children worldwide. Other contributions include serving on the board of advisors of the Centre for Global Engineering.
Cassandra Rosen (EngSci 1T5)
Rosen inspires undergraduate engineering students to apply their skills to make a positive impact. As a guest speaker and career interviewee, she has motivated hundreds of students to consider non-traditional career paths by sharing her journey from engineering graduate to government energy policy advisor. She has also given back to the engineering community through five years of involvement in the Engineering Alumni Mentorship Program, participating in the letter-writing campaign for newly admitted students, and reviewing Engineering Science Research Opportunities Program applications.
(Janet) Zhao Ping Tang (CompE 9T9)
Tang is an exceptional volunteer with U of T Engineering who promotes equity and opportunity in her role as chair of the Alumni Network Nominations and Governance Committee. She has developed equitable processes that place volunteers in over two dozen leadership positions across the university. In addition, as an alumna in the Asia Pacific, Tang’s efforts have strengthened ties in this important region and expanded volunteer activity, greatly enhancing community and inclusivity.
Timothy S. Zeng (MSE 1T1)
Zheng’s commitment to students and fellow alumni at U of T Engineering is extraordinary. Since 2018, he has advised countless students as part of the Alumni Mentorship Program, offering valuable guidance through one-on-one and speed mentoring. Zheng has also made critical contributions as an admissions assessor, reviewing student applications with a view to shaping a diverse, high-achieving class of future engineers. His unwavering dedication and far-reaching contributions have left an indelible mark on the Skule™ community.
See the full listing of Arbor Award recipients from across U of T:
Researchers at U of T Engineering have observed that handwashing synthetic fabrics in water with higher total dissolved solids (TDS) leads to more microplastic fibres (MPF) being released, creating implications for billions of people without access to soft water or washing machines.
The study, described in a paper published in Scientific Reports, looked at polyester fabrics and how they fared when handwashed in various types of water.
Some fabrics were covered in a silicone-based coating meant to reduce the MPF release, but the researchers found that the efficacy of this coating varied under different conditions.
According to a report from the Changing Markets Foundation, synthetic fibres — such as polyester, nylon and acrylic, mainly used in fast fashion — account for about two-thirds (69%) of textile production and are projected to rise to nearly three-quarters (73%) by 2030.
When synthetic fabrics are laundered, the friction caused by the laundering process leads to MPFs being released into waterways.
A significant contributor to global plastic pollution, microplastics are difficult to fully remove from water. While the impacts to human health remain unclear, microplastics are a risk to marine life, as they can block digestive tracks and cause injury when swallowed.
Professor Kevin Golovin’s (MIE) DREAM lab had previously created a silicone-based coating to reduce friction in the laundering process and prevent the fibres from breaking off, but the coating was only tested with machine laundering fabrics.
When Amanuel Goliad (MSE 2T3, MASc student), lead researcher and author on the paper, started asking how the coating fared in hand-washed cycles, he realized there was a research gap and decided to address it.
Goliad, whose family is from Ethiopia, grew up knowing about handwashing and understanding how prevalent it is.
“Nearly two-thirds of the world does not have access to a washing machine,” says Goliad.
“Most people around the globe hand wash, yet nearly all the microfibre research focuses on machine laundering in high-resource settings.”
To conduct his study, Goliad adapted a bamboo washboard-based method from another research paper, noting that so little research is done on hand washing that it was difficult to even find a standardized method to pull from.
He then washed green and black polyester fabrics, both coated and uncoated, using deionized, tap and Lake Ontario water. After washing, he filtered the wash water to count and analyze the MPFs.
Under the microscope, Goliad found that not only were there significant amounts of MPFs being released but also that the coating didn’t always prevent as much MPF release as it had in previous research using washing machines.
When looking at the coated green polyester fabric, the coating reduced fibre shedding by about 92% in deionized water but only 37% in Lake Ontario water, illustrating how its efficacy declines as TDS increases.
“The biggest impact in the efficacy of the coating comes from the type of wash water,” says Golovin.
“Most people that hand wash clothing use whatever body of water is locally available; it could be a river, an ocean, a lake. There are more total dissolved solids within them, and that affects the release of these microfibres more than people realize.”
At the same time, most research is being conducted in labs using deionized water, which has a TDS of 0, meaning that studies don’t reflect the real washing conditions of much of the world.
“There are additional implications for communities that don’t have access to laundry machines,” says Golovin.
“They’re the ones being exposed to more microfibres, but the policies and standards don’t reflect this. A potential action item resulting from this research and hopefully follow-up research is that those communities might need better water filtration systems than what global policy is stipulating, because they’re exposed to more MPFs.”
Another surprising find in the study were the actual lengths of the fibres.
“Higher TDS levels resulted in shorter fibre lengths,” says Goliad.
“That’s important because shorter fibres are harder to filter out in filtration systems; they spread more quickly and they’re more easily ingested by aquatic life.”
Golovin says the discovery of shorter fibres also have implications for how they’re currently measured.
“We have a new hypothesis that the dissolved minerals in harder water may be breaking the fibres into smaller pieces,” says Golovin.
“This affects how we measure microfibre release. If they’re being chopped into smaller fragments, simply counting fibres does not give an accurate picture.”
Golovin is advocating for measuring the total mass of the fibres released over just the count. He also notes his lab is researching fabric coating that can better withstand being hand washed in water with higher TDS.
“I hope this work highlights the environmental impact of hand washing and the need for more inclusive research,” says Goliad.
An interdisciplinary case study from researchers at U of T Engineering and the Department of Geography & Planning demonstrates the challenges that can arise when governments adopt a ‘smart cities’ strategy — and points the way toward possible solutions.
The study revolved around the city of Coimbatore in India’s Tamil Nadu state. Municipal water there is supplied via an intermittent system, which is turned on and off for each neighbourhood at various times throughout the week or month.
“More than a billion people around the world get their water intermittently,” says Professor David Meyer (CivMin), who studies these types of systems, including how to effectively model them.
“For many cities, upgrading to a 24/7 water supply is just not feasible. But one thing they can do as a stop-gap measure is to post the schedule online, so their users can at least plan around the times when they will receive water.”
This was the case for Coimbatore: in line with the Smart Cities initiative launched by India’s national Ministry of Housing and Urban affairs, the city decided to post its water schedules online.
“When they started posting the data online in April 2022, it gave us an opportunity to study the impact that open data and digital transparency can have on municipal services,” says Professor Nidhi Subramanyam from the Department of Geography & Planning, co-author along with Meyer of the new study, which is published in Environmental Research: Infrastructure and Sustainability. The research was funded by a Catalyst Grant from U of T’s Data Sciences Institute.
“As our study shows, it turned out to be a pretty laborious task, and it just couldn’t be sustained. They stopped posting after just a few months.”
Meyer says one of the key challenges was the format in which the data was provided, as well as its sheer volume.
“Each day, city staff would post a 50-page PDF document, a digitized version of the internal paper documents they used to determine the water schedule,” he says.
“But as a user, you don’t care about most of that: you only want to know when your taps are going to be turned on. To find that, you have to scan through hundreds of rows of text, looking for your street name. And it might be in a different place each time — or it might not be there at all, which would mean that you’re not getting any water that day.”
Meyer uses the analogy of a rainstorm in a desert to describe the switch.
“Before this, there was no data at all, like a dry desert with no rain,” he says.
“And then all of a sudden, you have a torrent of data, like a flood. But that doesn’t make things better; instead, it creates a whole new set of challenges.”
In the paper, the team outlines simple changes that could have made the data much more useful. For example, posting the data in the form of a machine-readable spreadsheet instead of a PDF would have enabled third-party developers to create an app that automatically sends users a text message when their water is coming on.
“Why didn’t they do that? To be empathetic to the city workers who we interviewed, a lot of it comes down to resources,” says Subramanyam.
“The utility didn’t hire anyone to be in charge of the new system, or to think through the best way to do it. Instead, they just added it to the list of tasks that current workers had to do, without increasing their pay or providing incentives. So it’s no surprise that they did it in a way that would be easy, rather than useful.”
“There’s also an element of ‘silent resistance.’ If you are asked to take on a new project that significantly adds to your workload, but you are not compensated for it, you have a good reason to want the project to fail. And in the end, that’s what happened here.”
Meyer says that while implementation was not effective in this case, the strategies of digital transparency and open data still have the potential to improve how cities work. He hopes that the team’s work can point the way toward best practices that might enable these tools to better live up to their promise.
“Right now, there’s no standard for how to do this effectively, so everyone is just kind of making it up as they go along,” he says.
“What we’re hoping is that by highlighting what didn’t work in this case study, and by suggesting what might have worked better, we can set the stage for a more successful implementation.
“If more places provide open data that is accurate, timely and accessible, it will do a lot to reduce the uncertainties and stress resulting from inadequate water supply.”
A new open-access tool created by U of T Engineering researchers provides a systematic way to organize and synthesize knowledge about metal–organic frameworks (MOFs) — a class of materials with applications in drug delivery, catalysis, carbon capture and more.
Metal–organic frameworks (MOFs) are an exceptionally versatile class of materials, distinguished by their ultra-high surface area and precisely tunable chemistry. Some MOFs have surface areas reaching up to 7,000 m²/g, meaning that a gram of this material contains enough internal surface area to cover a football field.
This unique structure enables a wide range of promising applications. Some can be used as molecular sieves, separating carbon dioxide from other gases so it can be captured and sequestered. Others grab onto tiny molecules, enabling them to be detected at extremely low concentrations. Still others can help speed up industrially important reactions, or deliver drugs to certain areas of the body.
The growing importance and transformative potential of MOFs in science and technology is underlined by the fact that they were the subject of the 2025 Nobel Prize in Chemistry.
But with studies on MOFs accelerating across more than 25 application domains, keeping track of the field’s rapidly growing body of knowledge has proven increasingly challenging — not just for researchers, but also for the AI tools intended to support scientific discovery.
A team led by Professor Mohamad Moosavi in the Department of Chemical Engineering & Applied Chemistry, and the Vector Institute, has developed a new system to help address that challenge.
Their new tool is named Unifying Chemical Data for MOFs, abbreviated to MOF-ChemUnity. The work has been published in the Journal of the American Chemical Society, one of the most prestigious journals in chemistry; the study was selected for the cover of a recent issue.
“Scientific discovery begins with reading and synthesizing the literature, but this remains one of the most difficult steps to automate,” says Moosavi.
“MOF-ChemUnity creates a unified foundation that both researchers and AI systems can build on.”
A structured map of MOF knowledge
The remarkable tunability of MOFs makes them suitable for a wide range of technologies, but the breadth and diversity of research across disciplines have made the field increasingly complex to navigate.
MOF-ChemUnity addresses this challenge using a structured and scalable knowledge graph that systematically extracts and links information from MOF research papers, crystal structure repositories and computational materials databases.
At the core of the system is a multi-agent large language model (LLM) workflow designed to connect chemical names in the literature to the correct crystal structures. This enables synthesis procedures, material properties and potential applications to be represented in a consistent, machine-readable format.
“A knowledge graph connects pieces of information like a web, linking things, like a MOF, its metal node, synthesis protocol, and adsorption property through their relationships — ‘made from’, ‘synthesized’, ‘used for’,” says Moosavi.
“This lets AI not just store data but understand and reason about how materials, properties and applications are connected — exactly what MOF-ChemUnity enables.”
Reducing AI hallucination through literature grounding
The team demonstrated the system’s impact by integrating the knowledge graph with large language models to build a literature-informed AI assistant for MOFs. Unlike standard AI systems, which can produce plausible-sounding but incorrect statements, the literature-informed assistant draws on verified experimental and computational records.
In blind evaluations performed by MOF experts from multiple institutions, the assistant’s responses were consistently rated as more accurate, interpretable and trustworthy than those produced by baseline LLMs such as GPT-4o.
“This approach reduces hallucination, which is one of the major obstacles in applying large language models to scientific domains,” Moosavi says.
“By grounding AI responses in curated and linked literature, we can support more reliable scientific reasoning.”
A foundation for future materials discovery
The U of T team — Moosavi and his graduate students, Thomas Pruyn and Amro Aswad (both ChemE), who were key contributors to the work — have made the dataset and code openly available on GitHub, aiming to support continued progress in materials science and AI-driven research.
The main funder is the National Research Council of Canada’s Materials for Clean Fuels Challenge Program, and U of T’s Acceleration Consortium and Data Science Institute.
Moosavi says the project lays groundwork for a broader shift in how scientific knowledge is organized and accessed.
“This work will help break down silos in scientific research,” Moosavi says.
“Human researchers are limited by the number of papers they can read, but MOF-ChemUnity takes a first step toward enabling AI systems that can process data across fields.
“It establishes a new paradigm for literature-informed discovery, and we envision it as the beginning of generalized knowledge systems that can accelerate research across many fields.”