Materials Science

Chemical Engineering

Sustainability

Subheadline

“Our study is the first reported instance of electrochemically removing copper from steel and reducing impurities to below alloy level”

Researchers at the University of Toronto’s Faculty of Applied Science & Engineering have designed a novel way to recycle steel that could help decarbonize several manufacturing industries and usher in a circular steel economy.

The new method introduces an innovative oxysulfide electrolyte for electrorefining, an alternative way of removing copper and carbon impurities from molten steel. The process also generates liquid iron and sulfur as by-products.

It’s outlined in a new paper published in Resources, Conservation and Recycling and co-authored by Jaesuk (Jay) Paeng, a PhD candidate in the department of chemical engineering and applied chemistry, William Judge, a PhD alum from the department of materials science and engineering, and Professor Gisele Azimi from the department of chemical engineering and applied chemistry.

“Our study is the first reported instance of electrochemically removing copper from steel and reducing impurities to below alloy level,” says Azimi, who holds the Canada Research Chair in Urban Mining Innovations.

Currently, only 25 per cent of steel produced comes from recycled material. But the global demand for greener steel is projected to grow over the next two decades as governments around the world endeavour to achieve net-zero emission goals.

Steel is created by reacting iron ore with coke – a prepared form of coal – as the source of carbon and blowing oxygen through the metal produced. Current processes generate nearly two tonnes of carbon dioxide per tonne of steel produced, making steel production one of the highest contributors to carbon emissions in the manufacturing sector.

Traditional steel recycling methods use an electric arc furnace to melt down scrap metal. Since it is difficult to physically separate copper material from scrap before melting, the element is also present in the recycled steel products.

“The main problem with secondary steel production is that the scrap being recycled may be contaminated with other elements, including copper,” says Azimi.

“The concentration of copper adds up as you add more scrap metals to be recycled, and when it goes above 0.1 weight percentage in the final steel product, it will be detrimental to the properties of steel.”

Copper cannot be removed from molten steel scrap using the traditional electric arc furnace steelmaking practice, so this limits the secondary steel market to producing lower-quality steel product, such as reinforcing bars used in the construction industry.

“Our method can expand the secondary steel market into different industries,” says Paeng. “It has the potential to be used to create higher-grade products such as galvanized cold rolled coil used in the automotive sector, or steel sheets for deep drawing used in the transport sector.”

To remove copper from iron to below 0.1 weight percentage, the team had to first design an electrochemical cell that could withstand temperatures up to 1,600 degrees Celsius.

Inside the cell, electricity flows between the negative electrode (cathode) and positive electrode (anode) through a novel oxysulfide electrolyte designed from slag — a waste derived from steelmaking that often ends up in cement or landfills.

“We put our contaminated iron that has the copper impurity as the anode of the electrochemical cell,” says Azimi. “We then apply an electromotive force, which is the voltage, with a power supply and we force the copper to react with the electrolyte.”

“The electrolyte targets the removal of copper from the iron when we apply electricity to the cell,” adds Paeng. “When we apply electricity on the one side of the cell, we force the copper to react with the electrolyte and come out from iron. At the other end of the cell, we simultaneously produce new iron.”

Azimi’s lab collaborated on the research with Tenova Goodfellow Inc., a global supplier of advanced technologies, products and services for metal and mining industries, where study co-author Judge works as a senior research and development engineer.

Looking forward, the team wants to enable the electro-refining process to remove other contaminants from steel, including tin.

“Iron and steel are the most widely used metals in the industry, and I think the production rate is as high as 1.9 billion tonnes per year,” says Azimi.

“Our method has great potential to offer the steelmaking industry a practical and easily implementable way to recycle steel to produce more of the demand for high-grade steel globally.” 

��˾��ֱ�� Engineering research aims to improve design of small-scale modular reactors for the nuclear industry

siddiq22 — Tue, 18 Jul 2023 19:27:08 +0000

��˾��ֱ�� Engineering research aims to improve design of small-scale modular reactors for the nuclear industry

siddiq22 Tue, 07/18/2023 - 15:27

Cutline

PhD candidate Xiao Shang works with a metal 3D printer in Assistant Professor Yu Zou’s lab (photo by Neil Ta)

Topic

Nuclear Power

Subheadline

Over the next three years, researchers from the Faculty of Applied Science & Engineering will lead projects that could shift how and where nuclear power is used

Small modular reactors (SMRs) represent a new paradigm that could change how and where nuclear power is used to meet our energy needs – and research from the University of Toronto's Faculty of Applied Science and Engineering could help point the way forward.

Professors Greg Jamieson in the department of the department of mechanical and industrial engineering, Oh-Sung Kwon in the department of civil and mineral engineering and Assistant Professor Yu Zou in the department of materials science and engineering, recently received funding from the NSERC-CNSC Small Modular Reactors Research Grant Initiative.

Over the next three years, each of them will be leading a project that seeks to improve the design of SMR technology, from the materials used in manufacturing to the ways in which they are operated.

“Canada has a long history in the nuclear space, and a lot of experience building and operating nuclear power plants,” says Jamieson, who holds the Clarice Chalmers Chair of Engineering Design and is co-director of the Cognitive Engineering Laboratory.

“So far, these have all been large facilities designed to meet the needs of major population centres. But we also have many communities and natural resources that are located hundreds or thousands of kilometres away from these big cities. With a geography like that, SMRs start to make a lot of sense.”

While there are currently no SMRs in commercial operation, several companies and organizations around the world are working on pilot facilities to demonstrate proof of concept. For example, Ontario Power Generation has begun site preparation activities for an SMR project at its existing Darlington site in the Greater Toronto Area.

These plants would be small – producing less than 300 megawatts of power, as compared to two or three times that amount from Canada’s existing plants – and built with pre-fabricated components that could be shipped to remote locations and assembled on site.

Since they operate without producing any greenhouse gas emissions, SMRs are seen as a potentially cleaner replacement for the diesel generators that are currently the industrial standard in remote locations – and electricity isn’t all they produce.

“Like all nuclear plants, SMRs generate heat, which produces the steam that is used to run the turbines,” Jamieson says.

“But you could also use this heat in other ways – for example, district heating, or for industrial processes such as hydrogen generation or the early stages of oil sands processing. There are a lot of possibilities.”

(L-R) Greg Jamieson, Oh-Sung Kwon and Yu Zou are all leading new research projects that look at various aspects of small modular reactors (supplied photos)

As a human factors researcher, Jamieson will be focusing on how the plant’s operators will monitor and control the technology. His project builds on some of his previous experience with the nuclear industry, but also represents a contrast to current industry standards.

“Large nuclear plants have operating procedures oriented around a single crew of operators monitoring a single reactor,” Jamieson says.

“But small modular designs open up new possibilities – such as a single crew monitoring multiple reactors – which raises questions about how you distribute human attention.”

Many proposed SMR systems also include what is known as “inherently safe design.” This means that systems are designed to passively shut down if operating conditions deviate from normal.

“Inherently safe design is a good idea, but we want to understand if there are situations where operators, possibly as a result of misinterpreting data, might mistakenly override those systems,” Jamieson says.

“This is something that was a factor in previous nuclear accidents, such as at the Three Mile Island facility in the U.S.”

In addition to differences in their potential modes of operation, SMRs might also require the use of different materials than current reactors – those that can stand up to harsher working environments. This aspect is the focus of Zou’s research project.

“In today’s reactors, water is usually used as the cooling fluid,” says Zou, principal investigator of the Laboratory for Extreme Mechanics & Additive Manufacturing.

“But many SMR designs use molten salts as the coolant, which can be more corrosive than water. Other designs use water, but they operate at much higher temperatures and pressures than traditional reactors. This means that the pipes, heat exchangers and other components need to be able to stand up to much harsher conditions.”

Zou and his team are working with collaborators at Natural Resources Canada and Dalhousie University to study how various materials might react to these tougher conditions. These might include nickel or iron-based alloys in common use today, but they will also consider new materials – such as high-entropy alloys – that haven’t been used for these applications before.

Components for SMRs could be made via additive manufacturing, also known as 3D printing. This method, which Zou’s team has expertise in, can significantly reduce the time from the development to the production.

The team will conduct physical experiments in the lab to test the mechanical properties of these materials, then feed the results into a set of computer simulations. Those simulations, in turn, will inform the development of future lab experiments in an iterative approach.

“Our goal is to build up a database that could be consulted by the designers of future SMRs,” Zou says. “It would also help regulators, as the lack of data about material behaviour under the relevant conditions makes it hard to assess safety.”

For their part, Kwon and his team are looking at how SMRs might react to seismic activity.

“Seismic analysis involves looking at how vibrations caused by seismic waves will affect a structure, including whether or not there are resonances that would amplify the effects of these vibrations,” Kwon says.

“In the case of a nuclear plant, we are interested not only in how vibrations might affect the building itself, but also the equipment within the building.”

One of the factors that Kwon and his team are focusing on is the properties of the soil underneath the reactor and containment buildings.

“Today’s plants undergo a lengthy site selection process that ensures they are seated on stiff, compacted soil that will not liquify in the case of a seismic event,” he says.

“But SMRs are designed to be shipped to remote locations, where there is less choice about where to situate them, so they may have to be designed to work on softer soils. In Canada’s North in particular, they might be seated on permafrost. If climate change causes that permafrost to melt, it could affect the seismic resilience of the facility.”

While SMRs are still a long way from widespread application, research from projects such as these can inform their development and keep Canada at the forefront of innovation in the sector.

Meet five women who are among ��˾��ֱ�� Engineering's 'grads to watch' in 2023

siddiq22 — Thu, 22 Jun 2023 21:06:04 +0000

Meet five women who are among ��˾��ֱ�� Engineering's 'grads to watch' in 2023

siddiq22 Thu, 06/22/2023 - 17:06

Cutline

Left to right: Kim Watada, Anais Poirier, Saskia van Beers, Maeesha Biswas and Michelle Lin (photo of Biswas by Dewey Chang, Lin by Mymy Tran, other photos supplied)

Topic

electrical engineering

As students from the University of Toronto's Faculty of Applied Science & Engineering celebrated their convocation this week, they looked ahead to a future where they will draw on their education to address pressing challenges around the world.

They now join a global network of ��˾��ֱ�� Engineering alumni whose creativity, innovation and global impact embody the spirit of the faculty and the ��˾��ֱ�� community.

Here are five inspiring women from the Faculty of Applied Science & Engineering's annual Grads to Watch list – each selected by their home departments and institutes.

Maeesha Biswas

Bachelor’s degree in industrial engineering plus professional experience year co-op

During her time as an undergraduate industrial engineering student, Maeesha Biswas’ academic interests were focused on health-care systems, human factors, technology and design geared at understanding people better.

She also devoted more than 2,000 hours to various activities and organizations, including planning the Undergraduate Engineering Research Day (UnERD) in 2020 as co-chair; and co-founding and co-hosting 1% Inspiration, a podcast that features stories and wisdom from the ��˾��ֱ�� Engineering community, including faculty, alumni and current students.

“After UnERD 2020 – which was held online due to the COVID-19 lockdown – we observed some students miss out on career development and networking opportunities due to a lack of on-campus interactions,” she says. “We created the podcast in response and since it launched, it has received over 1,100 listens over 22 episodes.”

After graduation, Biswas is looking forward to working on a startup with some of her fellow graduates to build generative artificial intelligence tools for media creators.

“I began learning to be a software developer during my co-op at PocketHealth – a company which helps patients share their diagnostic imaging records and own their medical information,” she says.

“I want to continue to enrich human lives and experiences through software technology, and I believe my most important life’s work will be here.”

Michelle Lin

Bachelor’s degree in materials science and engineering, plus professional experience year co-op

As a commuter student, Michelle Lin made a great effort to balance her academics with extra-curriculars and part-time work. She participated in intramural ultimate frisbee starting in her ﬁrst year and has held mentorship and outreach roles within the faculty.

During her co-op work term, she had the opportunity to hold two positions at Li-Cycle, a North American leader in the recovery and recycling of lithium-ion batteries, which was co-founded by a ��˾��ֱ�� Engineering alumnus.

“I was able to gain different perspectives on the business and all the work it takes to ensure that the different sectors are functioning cohesively towards the same goal,” she says. “It’s an evolving industry, and it was amazing to see the rapid growth the company and industry experienced in just 16 months.”

Lin will be starting a master’s in material science and engineering in the fall, which will allow her to gain more knowledge and expertise on materials characterization.

“I hope to be able to contribute positive change in the sustainability space and promote engineering and STEM to younger generations, especially girls and women,” she says. “I would love to be a source of inspiration for other women in engineering the same way my role models were for me.”

Anaïs Poirier

Bachelor's degree in electrical engineering, plus professional experience year co-op

In studying engineering, Anna Poirier found an opportunity to effect real change – and that is how she plans to use her degree.

For her PEY co-op, Poirier moved to Kentucky to work as a software engineering intern at Space Tango, a microgravity research company.

During this time, a colleague suggested she apply for the Zenith Canada Pathways Fellowship, Canada’s first space fellowship, which aims to build a more inclusive Canadian space sector.

“I was selected as a fellow in the inaugural class, leading to a summer internship at GHGSat,” Poirier says. “I got to experience the positive global impact that working in the space industry can have.”

Poirier will be moving to San Francisco after graduation to work as a software engineer at Zipline, where she will test flight hardware. The company, which manufactures drones that serve as eco-friendly delivery vehicles, delivered over a million COVID-19 vaccines to Ghana.

“I am excited to be working in a multi-disciplinary role that will use both the electrical and computer sides of my degree, and for a company whose mission I strongly believe in,” she says.

Saskia van Beers

Bachelor’s degree in engineering science, plus professional experience year co-op

While her engineering classes taught Saskia van Beers how to learn and think critically about the world around her, she was able to put those concepts into practice in her extracurricular activities.

"My worldview shifted greatly through all the initiatives I got to be a part of,” she says. “I definitely feel like I have undergone a lot of personal growth.”

From her role as co-president of Engineers Without Borders to co-chairing both the Engineering Science Club and the Sexual Violence Education and Prevention group, van Beers has worked tirelessly to help make all students feel welcome and seen.

Along with her classmate Savanna Blade, she ran a virtual consent culture town hall that brought together more than 80 of her fellow engineering science students to discuss all aspects of consent and the kinds of change they would like to see within their community.

After graduation, van Beers plans to pursue the collaborative specialization in engineering education program at the master's level at ��˾��ֱ��, with research focused on the intersectionality between equity advocacy work and the fundamentals of engineering education.

“I have been a longstanding believer that diversity within the engineering field allows for better engineering progress,” she says. “I would like to continue to make a positive impact on the changing culture of engineering.”

Kim Watada

Bachelor’s degree in chemical engineering plus professional year experience co-op

Kim Watada is graduating with nearly two years of experience in sustainability consulting, research and investing already under her belt.

“There are a lot of ways you can work in sustainability, and coming from an engineering background has given me the chance to explore many different paths,” she says.

“I’ve built a cleantech startup, worked in decarbonization strategy and studied renewable energy in Iceland. With each new perspective, I’ve been able to hone where my interests lie in sustainability and climate action.”

This spring, Watada and her team – the only one from Canada – won the Emerging Markets prize at the Climate Investment Challenge, a graduate-level climate finance design competition run by Imperial College London.

All this experience will come in handy after graduation, as Watada completes an internship with the United Nations’ Circular Economy and Resource Efficiency Unit in Vienna before taking up a position in management consulting for the Boston Consulting Group.

In the future, Watada hopes to leverage her knowledge to bridge the gap between environmental need, clean technology and tangible climate action.

“The greatest skill I have learned at ��˾��ֱ�� is how to be curious,” she says. “Being intrinsically open to learning new things is the key to solving problems in whatever field you choose.”

Read about all 15 of ��˾��ֱ�� Engineering’s ‘grads to watch’ 2023

Using quantum-inspired computing, ��˾��ֱ�� Engineering and Fujitsu discover improved catalyst for clean hydrogen

lanthierj — Fri, 16 Dec 2022 19:26:58 +0000

Using quantum-inspired computing, ��˾��ֱ�� Engineering and Fujitsu discover improved catalyst for clean hydrogen

lanthierj Fri, 12/16/2022 - 14:26

Cutline

��˾��ֱ�� Engineering PhD candidates Jehad Abed (left) and Hitarth Choubisa with a vial of the newly synthesized catalyst for hydrogen production, which was discovered with the help of a new quantum-inspired computing technique (photo by Tyler Irving)

Topic

Electrical & Computer Engineering

Collaboration

Quantum Computing

Sustainability

Researchers from the University of Toronto's Faculty of Applied Science & Engineering and Fujitsu have developed a new way of searching through ‘chemical space’ for materials with desirable properties.

The technique has resulted in a promising new catalyst material that could help lower the cost of producing clean hydrogen.

The discovery represents an important step toward more sustainable ways of storing energy, including from renewable but intermittent sources, such as solar and wind power.

“Scaling up the production of what we call green hydrogen is a priority for researchers around the world because it offers a carbon-free way to store electricity from any source,” says Ted Sargent, a professor in the Edward S. Rogers Sr. department of electrical and computer engineering and senior author on a new paper published in Matter.

“This work provides proof-of-concept for a new approach to overcoming one of the key remaining challenges, which is the lack of highly active catalyst materials to speed up the critical reactions.”

Today, nearly all commercial hydrogen is produced from natural gas. The process produces carbon dioxide as a byproduct: if the CO2 is vented to the atmosphere, the product is known as ‘grey hydrogen,’ but if the CO2 is captured and stored, it is called ‘blue hydrogen.’

By contrast, ‘green hydrogen’ is a carbon-free method that uses a device known as an electrolyzer to split water into hydrogen and oxygen gas. The hydrogen can later be burned or reacted in a fuel cell to regenerate the electricity. However, the low efficiency of available electrolyzers means that most of the energy in the water-splitting step is wasted as heat, rather than being captured in the hydrogen.

��˾��ֱ�� Engineering PhD candidates Jehad Abed (left) and Hitarth Choubisa with an electrolyzer capable of splitting water into hydrogen and oxygen gas. The newly discovered catalyst could increase the efficiency of this reaction (photo by Tyler Irving)

Researchers around the world are racing to find better catalyst materials that can improve this efficiency. But because each potential catalyst material can be made of several different chemical elements, combined in a variety of ways, the number of possible permutations quickly becomes overwhelming.

“One way to do it is by human intuition, by researching what materials other groups have made and trying something similar, but that’s pretty slow,” says department of materials science and engineering PhD candidate Jehad Abed, one of two co-lead authors on the new paper.

“Another way is to use a computer model to simulate the chemical properties of all the potential materials we might try, starting from first principles. But in this case, the calculations get really complex, and the computational power needed to run the model becomes enormous.”

To find a way through, the team turned to the emerging field of quantum-inspired computing. They made use of the Digital Annealer, a tool that was created as the result of a long-standing collaboration between ��˾��ֱ�� Engineering and Fujitsu Research. This collaboration has also resulted in the creation of the Fujitsu Co-Creation Research Laboratory at the University of Toronto.

“The Digital Annealer is a hybrid of unique hardware and software designed to be highly efficient at solving combinatorial optimization problems,” says Hidetoshi Matsumura, senior researcher at Fujitsu Consulting (Canada) Inc.

“These problems include finding the most efficient route between multiple locations across a transportation network, or selecting a set of stocks to make up a balanced portfolio. Searching through different combinations of chemical elements to a find a catalyst with desired properties is another example, and it was a perfect challenge for our Digital Annealer to address.”

In the paper, the researchers used a technique called cluster expansion to analyze a truly enormous number of potential catalyst material designs – they estimate the total as a number on the order of hundreds of quadrillions. For perspective, one quadrillion is approximately the number of seconds that would pass by in 32 million years.

The results pointed toward a promising family of materials composed of ruthenium, chromium, manganese, antimony and oxygen, which had not been previously explored by other research groups.

The team synthesized several of these compounds and found that the best of them demonstrated a mass activity – a measure of the number of reactions that can be catalyzed per mass of the catalyst – that was approximately eight times higher than some of the best catalysts currently available.

The new catalyst has other advantages too: it operates well in acidic conditions, which is a requirement of state-of-the-art electrolyzer designs. Currently, these electrolyzers depend on catalysts made largely of iridium, which is a rare element that is costly to obtain. In comparison, ruthenium, the main component of the new catalyst, is more abundant and has a lower market price.

There is more work ahead for the team: for example, they aim to further optimize the stability of the new catalyst before it can be tested in an electrolyzer. Still, the latest work serves as a demonstration of the effectiveness of the new approach to searching chemical space.

“I think what’s exciting about this project is that it shows how you can solve really complex and important problems by combining expertise from different fields,” says electrical and computer engineering PhD candidate Hitarth Choubisa, the other co-lead author of the paper.

“For a long time, materials scientists have been looking for these more efficient catalysts, and computational scientists have been designing more efficient algorithms, but the two efforts have been disconnected. When we brought them together, we were able to find a promising solution very quickly. I think there are a lot more useful discoveries to be made this way.”

To help meet global EV demand, researchers develop sustainable method of recycling older lithium-ion batteries

Christopher.Sorensen — Mon, 03 Oct 2022 17:28:50 +0000

To help meet global EV demand, researchers develop sustainable method of recycling older lithium-ion batteries

Christopher.Sorensen Mon, 10/03/2022 - 13:28

Cutline

Professor Gisele Azimi and PhD candidate Jiakai (Kevin) Zhang have proposed a new, more sustainable method to recover valuable metals from lithium-ion batteries that have reached the end of their useful lives (photo by Safa Jinje)

Safa Jinje

Topic

Chemical Engineering

Graduate Students

Sustainability

A University of Toronto researcher has developed a new technique to help recycle the metals in lithium-ion batteries, which are in high demand amid surging global sales of electric vehicles.

Gisele Azimi, a professor in the departments of materials science and engineering and chemical engineering and applied chemistry in the Faculty of Applied Science & Engineering, and her team have proposed a new, more sustainable method to mine valuable metals – including lithium, but also cobalt, nickel and manganese – from lithium-ion batteries that have reached the end of their useful lifespan.

“Getting these metals from raw ore takes a lot of energy,” says Jiakai (Kevin) Zhang, a PhD candidate in chemical engineering and applied chemistry who is lead author on a new paper recently published in Resources, Conservation and Recycling.

“If we recycle existing batteries, we can sustain the constrained supply chain and help bring down the cost of EV batteries, making the vehicles more affordable.”

Part of Canada’s commitment to reach net-zero emissions by 2050 includes a mandatory target requiring 100 per cent of new light-duty cars and passenger trucks sold in the country to be electric by 2035.

Achieving this target will require an increase in the supply of critical metals, the price of which is already very high. For example, cobalt, a key ingredient in the cathode production of lithium-nickel-manganese-cobalt-oxide (commonly abbreviated as NMC) batteries widely used in EVs, is also one of the most expensive components of lithium-ion batteries due to its limited reserve.

“We are about to reach a point where many lithium-ion batteries are reaching their end of life,” says Azimi. “These batteries are still very rich in elements of interest and can provide a crucial resource for recovery.”

Not only can recycling provide these materials at a lower cost, but it also reduces the need to mine raw ore that comes with environmental and ethical costs.

The life expectancy of EV batteries is from 10 to 20 years, but most car manufacturers only provide a guarantee for eight years or 160,000 kilometres – whichever comes first. When EV batteries reach end of life, they can be refurbished for second-life uses or recycled to recover metals. But today, many batteries are discarded improperly and end up in landfills.

“If we keep mining lithium, cobalt and nickel for batteries and then just landfill them at end-of-life, there will be a negative environmental impact, especially if corrosive electrolyte leaching occurs and contaminates underground water systems,” says Zhang.

Gisele Azimi and Jiakai (Kevin) Zhang conducted their supercritical fluid extraction experiments in a 100-millilitre high-pressure reactor (photo by Safa Jinje)

Conventional processes for recycling lithium-ion batteries are based on pyrometallurgy, which uses extremely high temperature, or hydrometallurgy, which uses acids and reducing agents for extraction. These two processes are both energy intensive: pyrometallurgy produces greenhouse gas emissions, while hydrometallurgy creates wastewater that needs to be processed and handled.

In contrast, Azimi’s lab group is using supercritical fluid extraction to recover metals from end-of-life lithium-ion batteries. This process separates one component from another by using an extracting solvent at a temperature and pressure above its critical point, where it adopts the properties of both a liquid and a gas.

To recover the metals, Zhang used carbon dioxide as a solvent, which was brought to a supercritical phase by increasing the temperature above 31 C, and the pressure up to 7 megapascals.

In the paper, the team showed that this process matched the extraction efficiency of lithium, nickel, cobalt and manganese to 90 per cent when compared to the conventional leaching processes, while also using fewer chemicals and generating significantly less secondary waste. In fact, the main source of energy expended during the supercritical fluid extraction process was due to the compression of CO2.

“The advantage of our method is that we are using carbon dioxide from the air as the solvent instead of highly hazardous acids or bases,” she says. “Carbon dioxide is abundant, cheap and inert, and it’s also easy to handle, vent and recycle.” 

Supercritical fluid extraction is not a new process. It has been used in the food and pharmaceutical industries to extract caffeine from coffee beans since the 1970s. Azimi and her team’s work builds on previous research in the Laboratory for Strategic Materials to recover rare earth elements from nickel-metal-hydride batteries.

However, this is the first time that this process has been used to recover metals from lithium-ion batteries, she says.

“We really believe in the success and the benefits of this process,” says Azimi.

“We are now moving towards commercialization of this method to increase its technology readiness level. Our next step is to finalize partnerships to build industrial-scale recycling facilities for secondary resources. If it’s enabled, it would be a big game changer.”

The research was supported by the Natural Sciences and Engineering Research Council of Canada and Ontario’s Ministry of Economic Development, Job Creation and Trade.

Dynamic building facades inspired by marine organisms could reduce heating, cooling and lighting costs

geoff.vendeville — Fri, 15 Jul 2022 16:01:24 +0000

Dynamic building facades inspired by marine organisms could reduce heating, cooling and lighting costs

geoff.vendeville Fri, 07/15/2022 - 12:01

Topic

John H. Daniels Faculty of Architecture

Graduate Students

Institute of Biomedical Engineering

A new, low-cost “optofluidic” system designed by University of Toronto researchers – and inspired by marine life like fish, crab and krill – could help buildings save energy by dynamically changing the appearance of their exteriors.

“I don’t think it’s stretching the analogy too much to see buildings as living organisms,” says Raphael Kay, a master's student in the department of materials science and engineering in the Faculty of Applied Science & Engineering, who's supervised by Professor Ben Hatton in the same department.

“They have a metabolism, in terms of inward and outward energy flow. And they must respond to changing environmental conditions to maintain a comfortable and well-functioning interior,” Kay explains.

While buildings currently rely on mechanical systems such as heating and air conditioning to maintain a comfortable indoor temperature, Kay points out that many animals regulate energy transfer directly at the surface – that is, their skin.

Krill – shrimp-like marine organisms that thrive in vast numbers in certain areas of the ocean – are transparent, which means that UV light can damage their internal organs. In response, they have developed a dynamic shading system, shuttling pigment granules within the cells beneath their skin to darken themselves when it’s too bright out, and get lighter again when the sun fades.

Buildings also have a “skin” consisting of their exterior facades and windows. But today, these outer layers are mostly static and unchanging. As a result, the amount of light and heat coming into the building is often too high or too low, forcing the heating, cooling and lighting systems to work harder than they would otherwise have to.

“As a simple example, imagine opening your blinds when you need more daylight or solar heat, and closing them when you need less,” Kay says.

“That does save energy, but it’s pretty crude. In order to reap the full benefits, you need such a system to be automated and optimized to balance a whole range of factors in real time, from changes in temperature, solar intensity, angle and direction to the changing needs of the building’s occupants.”

There are some current technologies that can start to achieve this: adding computer-controlled motors to traditional roller blinds, or installing electrochromic windows, which can change their opacity in response to an applied electric voltage.

But in general, Kay sees the current set of tools as both too costly and too limited.

“Nearly all of these systems are expensive, rely on complicated manufacturing procedures, or can only switch between a limited range of opacities – for example, from very dark to only somewhat dark,” he says. “It’s also hard to achieve fine spatial gradations, such as shading one part of a windowpane but not another.”

In a paper published this month in Nature Communications, Kay, Hatton and their research team describe a new paradigm that overcomes these limitations. The prototype optofluidic cells consist of a layer of mineral oil approximately one millimetre thick, sandwiched between two transparent sheets of plastic, developed by Charlie Katrycz, a PhD candidate in materials science and engineering.

Through a tube connected to the centre of the cell, the researchers can inject a small amount of water containing a pigment or dye. Injecting this water “guest fluid” creates a bloom of colour, one that can be controlled via a digital pump that runs in both directions. Adding more water makes the bloom larger, while removing some makes it smaller.

The shape of the bloom can be controlled by the flow rate of the pump: low flow rates lead to a roughly circular bloom, while higher ones lead to intricate branching patterns.

“We’re interested in how ‘confined fluids’, of green, sustainable chemistries, can be used to change material properties,” says Hatton. “It’s very versatile: not only can we control the size and shape of the water in each cell, we can also tune the chemical or optical properties of the dye in the water. It can be any colour or opacity that we want.”

In addition to the prototypes, the team worked with Alstan Jakubiec, an assistant professor at the John H. Daniels Faculty of Architecture, Landscape and Design, to build computer models that simulated how a fully automated and optimized system using these cells would compare to one that used motorized blinds or electrochromic windows.

“What we found is that our system could reduce the energy required for heating, cooling and lighting by up to 30 per cent compared with the other two options,” says Kay. “The main reason for this is that we have much finer control over the extent and timing of solar shading. Our system is analogous to opening and closing hundreds of tiny blinds at different locations and times across a facade. We can achieve all this with simple, scalable and inexpensive fluid flow.”

The team also speculates on artistic possibilities. Large arrays of the cells could act like pixels, creating optofluidic displays capable of producing pointillist-style artworks. In their models, the team even simulated images of Albert Einstein and Marilyn Monroe.

Hatton hopes that the idea of using dynamic facades to save energy will shift conversations around both building design and climate change.

“In the developed world, buildings are responsible for something like 40 per cent of our emissions, which is more than any other individual sector,” says Hatton.

“Part of the reason for this is that we’ve designed buildings to be inflexible. Dynamic, adaptive buildings could reduce the temperature and daylight gradients that we have to push against, and potentially save a lot of energy. We hope our contribution will spark people’s imaginations.”

Meet six women who are among ��˾��ֱ�� Engineering's 'grads to watch' in 2022

Christopher.Sorensen — Thu, 16 Jun 2022 17:20:59 +0000

Meet six women who are among ��˾��ֱ�� Engineering's 'grads to watch' in 2022

Christopher.Sorensen Thu, 06/16/2022 - 13:20

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Clockwise from top left: Valerie Ajayi, Laura Berneaga, Sayeh Bayat, Saanjali Maharaj, Marie-Eve Caron and Julia Bincik.

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As they cross the stage at Convocation Hall, graduates from the University of Toronto’s Faculty of Applied Science & Engineering are marking the end of one journey and the beginning of another.

Having enriched the ��˾��ֱ�� community as undergraduate and graduate students, they now join a global network of ��˾��ֱ�� Engineering alumni who working to address pressing challenges around the world and inspire the next generation.

Here are six inspiring women from the Faculty of Applied & Engineering annual Grads to Watch list – each selected by their home departments and institutes.

Valerie Ajayi

Bachelor’s degree in mechanical engineering, plus professional experience year co-op

Between working part-time and commuting two hours each way from just outside of Brampton, Ajayi found it difficult in her first year to participate in ��˾��ֱ�� Engineering life, especially on weekends. But she did not let that challenge stand in her way for long.

“There are so many opportunities across a campus as large as St. George and a community as passionate as Skule,” she says, referring to the ��˾��ֱ�� Engineering community’s affectionate name for itself. “I wanted to take advantage of it as best as I could.”

Ajayi eventually found a place closer to campus and joined the Skule orientation committee, becoming its vice-chair of finance. She placed first in her categories in both the CUBE Biomedical Engineering Competition, as well as the ��˾��ֱ�� Engineering Kompetitions (UTEK). Her experience representing Skule at the Ontario Engineering Competition inspired her to lead UTEK the following year as its director. She currently serves as vice-president, finance of the ��˾��ֱ�� Engineering Society.

“It’s been great to have the chance to work with so many incredible students as we navigate what has been an uncertain and challenging time for all,” she says. “I’m very proud of the projects we were able to advance this year.”

Thanks to the Professional Experience Year Co-op Program, Ajayi is graduating with work experience at Bombardier and Comtek Advanced Structures. She plans to pursue a master’s degree focused on the solid mechanics of new materials, with applications in safety and sustainable production of composites for automotive and aerospace components.

“I have learned so much about leadership, discipline and passion through my extracurricular involvements,” says Ajayi. “I am certain that these will help me succeed in my future endeavours.”

Sayeh Bayat

PhD in biomedical engineering

In her thesis, Bayat aimed to develop “digital biomarkers” that can predict or explain neurodegeneration. For example, in one study she gathered mobility data from smartphones or other wearable devices to compare how older people – some with dementia and accompanied by family members – moved about their communities. The modes of transportation included by transit, bicycle, walking and by car.

“Using machine learning, we showed that there may be very subtle changes in driving behaviours that can be indicative of the earliest signs of Alzheimer’s disease,” she says.

Outside of her research, Bayat served as a student leader. As president of the TRI-KITE Executive Trainee Committee, she launched a Three Minute Thesis competition, created a peer mentorship program and supported her fellow students in topics such as job applications and financial literacy. She also served as co-chair of both the 2021 Toronto Biomedical Engineering Conference and of ILead: Grad, an organization within the Troost Institute for Leadership Education in Engineering.

“One of my proudest contributions is when we started to use our platform in ILead: Grad to host bi-weekly graduate conversation circles, which we called Caffeinated Grad Talks,” she says. “We wanted to offer students a safe and confidential space where they can talk about the stressors in graduate school and life.”

Bayat’s contribution to neurodegeneration research has already landed her a faculty position at the University of Calgary, where she is continuing the development of models and algorithms that leverage embedded technologies to monitor brain-related behaviours.

“I think this is where the future is headed,” she says. “My time at ��˾��ֱ�� has taught me the importance of working collectively and collaboratively; that in order to push the boundaries of science and innovation, we must engage end-users and stakeholders, share knowledge and achieve impact.”

Laura Berneaga

Master’s degree in mechanical engineering

Berneaga works on problems at the intersection of engineering and humanity.

Her thesis revolves around the manufacturing of ventilators – one of the earliest health-care bottlenecks exposed by the COVID-19 pandemic.

“We focused on the controller since it is the most complex component, responsible for all the major decisions the ventilator makes,” she says.

“Today, the code for the controller is highly dependent on the specific hardware components. We created a framework for an open-source design – one that could be adopted by manufacturers anywhere in the world, helping them quickly scale up in a crisis.”

An experienced student leader, Berneaga served as the president of the ��˾��ֱ�� Engineering Society during her undergraduate degree and as president of the Graduate Engineering Council of Students during her master’s degree.

“Both roles presented me with opportunities to advocate for better experiences for the students, and it was extremely rewarding to see initiatives I pushed for come to life,” she says.

“But I equally valued my involvement in projects such as Fr!osh Week and Skule Nite. I’ve always believed that you shouldn’t have to choose between the technical aspects of engineering and the more artistic and creative parts of your personality.”

This summer, Berneaga moved to Germany to take up an internship at Helmholtz-Zentrum Berlin. She is designing and implementing improvements to a highly sensitive X-ray spectroscopy machine, a piece of analytical equipment used across a wide range of disciplines.

Berneaga says that two big lessons she took from ��˾��ֱ�� Engineering were to never be afraid to follow your passion, and to take initiative for the things you want to achieve.

“It’s easy to go with the flow, but it’s so much more rewarding to take charge and pursue the things you want, the way you want them.”

Julia Bincik

Bachelor’s degree in materials science and engineering, plus professional experience year co-op

Bincik’s passion is environmental sustainability, and she is graduating with a feeling of confidence in her ability to have an impact in her chosen field.

“I feel well-equipped to make a positive difference,” she says.

Bincik credits the TrackOne program, which she did in the first year of her undergraduate studies, for sparking her interest in materials science engineering as a way to explore green technologies.

A highlight from her academic career was co-authoring an article on microplastics for the Society of Plastics Engineers Newsletter, which won first place at the University of Toronto Engineers Without Borders Green Plastics Article Competition.

Outside of class, Bincik volunteered as a counsellor for ��˾��ֱ��’s Da Vinci Engineering Enrichment Program as well as the ��˾��ֱ�� Engineering Academy, UTEA. She also participated in ecological conservation research in Honduras with U.K. biodiversity and climate research organization Operation Wallacea.

“There have been numerous times where I felt pushed to my limits with the demands of school and life,” says Bincik. “But I am glad this journey hasn’t been easy. I view challenges as opportunities, and I have tried to use difficult situations to build my resilience and better understand the importance of taking care of myself, looking out for others, and showing kindness and gratitude no matter what the circumstances.”

After graduation, Bincik will be working as a junior R&D Scientist at e-Zinc, a Toronto-based company that has developed electrochemical technology for storing energy in zinc metal. The company is one of the 2022 Global Cleantech 100.

“I am excited to return to the e-Zinc team, where I completed my PEY co-op, to continue work on the development of the air cathode component of the zinc-air battery.”

Marie-Eve Caron

Master’s degree in civil and mineral engineering

Caron describes her two years as a civil and mineral engineering student as a roller-coaster ride.

“It had its highs and lows,” she says. “But I am grateful for the support I had from those around me, including my thesis supervisor and members of the department.”

While many of her classes and projects were completed remotely, Caron was still able to immerse herself in the social life of her department through the CivMin Graduate Students Association (CivMinGSA), where she served as vice-president, social.

“We not only had good times during our events, but we were able to connect and share in the unique challenges of graduate studies,” she says.

She credits her CivMinGSA experiences, along with her studies, for allowing her communications skills to flourish and helping boost her self-confidence.

In the spring, Caron began her professional career at Agnico Eagle’s LaRonde Mine in Quebec, where she previously worked during her thesis project. As a ground control engineer-in-training, she is responsible for following up daily on the stability of underground excavations.

“High-stress conditions and seismicity are among the challenges we deal with,” she says. “My master’s degree under the supervision of Professor John Hadjigeorgiou has prepared me for this role.”

Caron’s thesis focused on data collection for rockburst investigations. It involved collecting all available design, implementation, monitoring and performance data to construct a timeline for each rockburst, which involves a sudden rupture or collapse of highly stressed rock in a mine.

“I have learned a lot in my field of study, and I now feel confident that I have established strong basis to strive in my career,” she says. “But I still have much to learn, and I am enthusiastic about it.”

Saanjali Maharaj

Bachelor’s degree in engineering science, plus professional experience year co-op

“My experience at ��˾��ֱ�� has been a time of discovery,” says Maharaj. “I learned so much about engineering design, innovations in the industry and working as part of a team.”

The time was also a period of self-discovery for Maharaj, as her various internships, courses and research experiences helped her find out what she is passionate about, charting the course of her career.

In 2019, Maharaj had “the amazing opportunity” to be an intern at the NASA Ames Research Center’s department of rotorcraft aeromechanics.

“I was the thermal lead in developing a drone to help mitigate the prevalent California wildfires,” she says. “Following that experience, I was a thermal-mechanical engineering intern at Intel Corporation.”

A significant achievement from her PEY Co-op at Intel was leading the research for a novel cooling technology that resulted in the submission of a patent application.

Maharaj has held leadership positions in co-curricular activities, including as rocketry division aerodynamics lead on the University of Toronto Aerospace Team (UTAT) and marketing director for the University of Toronto West Indian Students’ Association (WISA).

This summer, Maharaj is working on an asteroid mining project in collaboration with MDA. She is also looking forward to starting her master’s studies this fall at the ��˾��ֱ�� Institute for Aerospace Studies, where she will be supervised by Professor Prasanth Nair.

Ultimately, she hopes to make a positive contribution to the advancement of sustainable aviation.

“Sustainability is a passion of mine due in part to my Caribbean Island origins,” she says. “Trinidad and Tobago’s dependence on the aviation industry to maintain international connections fuels my desire to mitigate the industry’s environmental impact.”

Read about all 14 of ��˾��ֱ�� Engineering’s ‘grads to watch’ 2022

From Syria to ��˾��ֱ�� Engineering: How one student fled civil war to complete his degree

geoff.vendeville — Mon, 30 May 2022 19:48:38 +0000

From Syria to ��˾��ֱ�� Engineering: How one student fled civil war to complete his degree

geoff.vendeville Mon, 05/30/2022 - 15:48

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Edmund Shalhoub, a student in the Faculty of Applied Science & Engineering, will be graduating this June after coming to Canada in 2017 as a Syrian refugee (photo by Safa Jinje)

Safa Jinje

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Our Community

This June, Edmund Shalhoub will finally achieve his long-held ambition of graduating with a bachelor’s degree in engineering – a journey he started 12 years ago in Syria.

“In 2010, my life was quite normal: I went to school, I spent time with friends and I wanted to specialize in automobile and heavy machinery engineering, as part of a mechanical engineering degree,” says Shalhoub, who studied materials science and engineering at the University of Toronto.

“I always believed that having an engineering background – with all the technical and theoretical knowledge – would be my vehicle to make positive change in this world, to discover new things and to solve current problems.”

But achieving this goal was far from straightforward. In 2013, three years into his mechanical engineering education, Shalhoub was forced to flee his home country of Syria, where a civil war was raging. When an explosion occurred near Damascus University, close to Shalhoub's home, he realized it was no longer safe for him in Syria.

He arrived in Turkey in September 2013, determined to continue his studies. But since he only spoke Arabic and English, he spent his first year in Istanbul learning Turkish before starting over at Yildiz Technical University – where he earned a spot in the materials science engineering program.

While in Turkey, Shalhoub applied for refugee status through the United Nations High Commissioner for Refugees (UNHCR), and his application was approved and referred to the Canadian Embassy.

“When I got accepted to come to Canada, I was told I would have to leave Turkey soon,” he says. “I had to quit my studies again, and that was hard, but I was motivated by the great opportunity.”

Still, arriving alone in a new country was a terrifying experience, Shalhoub says. The experience was made easier by the support of the Canadian government through a resettlement and assistance program, which provided income for his first year in the country.

But Shalhoub was eager to pick up his studies where he left off.

“I started researching ��˾��ֱ�� while I was in Turkey and I learned it was one of the best universities in the world,” he says. “I felt like it was going to be my school – I actually felt it.”

Soon after arriving in Canada in 2017, Shalhoub visited the Faculty of Applied Science & Engineering admissions office and spoke with a representative, who listened to his story and advised him to take an English language assessment test as part of his application.

“I passed and received an offer for the 2017-18 academic year,” Shalhoub says. “I was able to transfer 10 courses from my previous universities, so I was a part-time student for my first two years.”

While his time at ��˾��ֱ�� Engineering proved to be challenging and full of emotional highs and lows, Shalhoub found a supportive community through his part-time work as a communications assistant in the office of the chief librarian at Robarts Library.

“Last November, I became a Canadian citizen, and my colleagues at the library threw me a surprise party to celebrate,” he says. “Everyone there has always made me feel so welcome.”

To overcome personal struggles during his second and third years of study, Shalhoub was able to rely on on-campus resources such as mindfulness and meditation sessions, as well as support from the Health and Wellness Centre. As for tuition, he received support from the university through the Scholars and Students at Risk Award Program, for asylum-seekers or refugees whose education was impacted by a changing political climate in their country of current or future study.

Living outside his country of origin has helped Shalhoub learn things about himself, he says. “I’ve discovered my strength and my ability to accomplish things I didn’t know I was even capable of when I lived in Syria. And I now know I want to help develop solutions for protecting our environment,” he says.

Shalhoub’s passion for environmentalism ultimately led him to pursue a minor in environmental engineering through ��˾��ֱ�� Engineering's cross-disciplinary programs office. He is still weighing his next move after graduation but says that his time at ��˾��ֱ�� will always stay with him.

“I am still not sure how exactly I am going to contribute to solving these problems,” he says, “but I know that I want to use my materials science and environmental engineering education, along with all the technical skills I learned during the last 12 years, to make a difference in the world.”

Listen to Edmund Shalhoub on CBC’s Metro Morning

Why are zebra mussels so sticky? Study could lead to new industrial coatings, medical adhesives

Christopher.Sorensen — Mon, 17 Jan 2022 19:43:22 +0000

Why are zebra mussels so sticky? Study could lead to new industrial coatings, medical adhesives

Christopher.Sorensen Mon, 01/17/2022 - 14:43

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A new study of zebra mussels, like this one growing in a tank in the lab of ��˾��ֱ�� Engineering researcher Eli Sone, offers insights into creating new medical adhesives as well as ways to prevent fouling of water intake pipes (photo by Angelico Obille)

Topic

Institute of Biomedical Engineering

A water tank full of coin-sized invertebrates may not be the first thing you’d expect to see in a materials science and engineering research lab.

But Eli Sone, a professor in the department of materials science and engineering in the University of Toronto’s Faculty of Applied Science & Engineering and the Institute of Biomedical Engineering, and his team have been studying both zebra and quagga mussels for years in the hope that they can help solve a diverse range of challenges.

Eli Sone

“There’s a materials science angle, but there’s also a biomedical angle,” says Sone. “On the one hand, these mussels are a problem in terms of what we call biofouling, so we’re looking to design materials or coatings to keep them from clogging water intake pipes, for example.”

“But on the other hand, if we understand why they stick so well, that could help us design things like non-toxic biodegradable glues, which could offer an alternative to internal stitches for surgery or localized drug delivery applications.”

Zebra and quagga mussels are native to the lakes and rivers of southern Russia and Ukraine. They arrived in the Great Lakes of North America in the 1980s – likely by hitching a ride in the ballast water of ships that departed from Europe.

They have since become invasive in many North American waterways, displacing native mussel species and fouling boats, water intake pipes and other infrastructure.

The team’s latest study, recently published in Scientific Reports, outlines new techniques for measuring the adhesion of zebra and quagga mussels to various surfaces.

“One of the challenges is how small these mussels are compared to other species,” says ��˾��ֱ�� Engineering alumnus Bryan James, who worked on the project as part of his undergraduate thesis and is now a post-doctoral scholar at the Woods Hole Oceanographic Institution in Woods Hole, Mass.

“The threads they use to attach themselves to surfaces are only a few millimetres long and as thin as a human hair. You can’t put them in a traditional apparatus for testing tensile strength.”

The team’s improvised solution involved a pair of fine-tipped, self-closing tweezers, a digital camera and a force gauge. With these, they were able to measure just how much force was required to break the protein-based glue that the mussels secrete.

The team found that the mussels adhered more strongly to glass than they did to plastics such as PVC or PDMS. This was expected, as glass is a hydrophilic (water-attracting) material similar to the rocks that the mussels use as substrates in nature. PDMS, on the other hand, repels water and is often applied to boat hulls to prevent biofouling.

But there were some surprises as well.

“The actual magnitude of these values was comparable to – or in some cases greater than – reported values for other species of mussels,” says James. “This suggests that there may well be something special about the glue they have evolved.”

After the threads had been detached, the team scanned the glue left behind on the surfaces using electron microscopy.

“On some surfaces we found that a thin protein residue was left behind after detachment,” says Kenny Kimmins, a current PhD student in Sone’s lab.

“This shows that the proteins at the interface interact very strongly with these surfaces even in wet conditions, which most synthetic adhesives can’t do.”

Sone and his team are continuing their research in the area, working with Associate Professor Ben Hatton on new types of surfaces to prevent fouling of critical infrastructure.

“Right now, people often use chemical treatment to remove the mussels,” says Sone. “That works, but it also kills everything else nearby. Having surfaces that are naturally hard for the mussels to stick to could offer a more environmentally sustainable option.”

The team is also analyzing the glues produced by both zebra and quagga mussels, with the aim of mimicking them in biomedical adhesives.

“Nature has had a few million years’ head start on us in terms of designing high-performance adhesives that are resilient even when wet,” says Sone. “If we can learn from that, we may be able to come up with better solutions than what we have right now.”

Graphene-like 2D material leverages quantum effects to achieve ultra-low friction

Christopher.Sorensen — Wed, 24 Nov 2021 00:28:21 +0000

Graphene-like 2D material leverages quantum effects to achieve ultra-low friction

Christopher.Sorensen Tue, 11/23/2021 - 19:28

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PhD candidate Peter Serles of ��˾��ֱ�� Engineering places a sample of magnetene in the atomic force microscope. New measurements and simulations of this material show that its low-friction behaviour is due to quantum effects (photo by Daria Perevezentsev)

Topic

Graduate Students