From emissions to eco-friendly engineering

When scientists and engineers learned to harvest power from steam, coal, and other fossil fuels during the Industrial Revolution, they used the underpinnings of chemical engineering to jumpstart a whole new way of life: electrified cities, global travel, and millions of products and innovations that dramatically improved our quality of life.

But every new energy source that has been discovered has led to unintended consequences for humanity and the ecosystem—including the biggest consequence of all, climate change.

For the past 20 years, many chemical engineers have shifted from producing energy from non-renewable resources that create environmental problems to finding sustainable solutions—including at UIC’s College of Engineering, where faculty, students, and alumni are working on new ways to capture carbon dioxide to keep it out of the atmosphere, harness bacteria and other sources for renewable energy, purify drinking water, and store and utilize power created by green technologies.

“During the Industrial Revolution that happened in the 1800s, all the industries that blew up were chemical industries,” said Meenesh Singh, an assistant professor of chemical engineering. “We are the reason why there are emissions. So now, chemical engineers are gearing up to resolve the issues.”

Chemical Engineering Department Head and Professor Vikas Berry said the skillsets developed through a chemical engineering education are perfect to address these areas and climate change.
“Chemical engineers know how materials work and how to convert energy from one form to another, and those are the two things are critical in understanding ways to generate usable energy from sustainable resources,” Berry said.

For Singh, solving environmental problems meant turning to nature itself for inspiration. He and his lab have been developing an artificial leaf for carbon capture research since 2016.

The leaf stemmed from his interest in finding a way to “decarbonize” chemical industries with a modular and flexible system that could capture CO2 from diluted sources, such as flue gasses coming out of a chemical plant, a crowded conference hall, or a smaller-scale factory that produces CO2 as a byproduct.

“We got some inspiration from nature’s photosynthesis process,” Singh said. “Leaves in nature complete this capture and conversion process in an efficient and robust manner and we wanted to integrate that.”

When carbon is captured in Singh’s system, an organic solvent attaches to available carbon dioxide to produce a concentration of bicarbonate, or baking soda, on the membrane. As bicarbonate builds, these negatively charged ions are pulled across the membrane toward a positively charged electrode in a water-based solution on the membrane’s wet side. The liquid solution dissolves the bicarbonate back into carbon dioxide, so it can be released and harnessed for fuel or other uses.

After proving artificial leaves work in theory and in the lab, Singh is moving forward with a large-scale demonstration by setting up the world’s largest CO2 capture and conversion unit in south Chicago. In addition, he and his group have been doing parallel work focused on using carbon to create common chemicals and products in a more sustainable way.

“We are heavily invested in CO2 capture and clean energy,” Singh said.

A more sustainable future also requires cleaner, greener ways of producing energy. To find new ways of generating electricity, Berry and his research team, including recently graduated PhD student Sheldon Cotts, turned to an unlikely source: bacteria.

The team is using the tiny organisms to build microbial fuel cells, biochemical devices that can generate electricity.

“We are living in bacteria’s world,” Cotts said. “They are an untapped resource. They are easy to grow and propagate and they survive in all types of adverse conditions. It’s high time we try and get along with these guys and use them as a resource. Their potential is endless.”

In the 1980s, scientists discovered bacteria can generate power when they are run over electrodes. But by using bacteria within microbial fuel cells, the researchers can also remove waste while generating power.

“An intriguing application we are seeing right now is using them in wastewater supplies from municipal wastewater sewage systems and industrial wastewater streams, where there is a lot of organic runoffs such as from breweries, wineries, or papermills,” Cotts said. The group has studied these fuel cells on a cellular level to try and improve their efficiency and increase the amount of power the bacteria can generate. They are also developing nanodevices in which a microchip could be powered by bacteria cells.

This means the devices would get their energy from the environment where they are, Berry said, and devices could be used in remote areas where other power sources are not available or in unique environments, such as in the ocean or inside the human body.

“The quality of life of any community can be measured by the amount of energy that is used,” Berry said. “We have to figure out a way to get that critical energy, but in a sustainable way.”