Schematic of the integrated system with migration-assisted moisture-gradient CO2 capture and electrochemical CO2 reduction reaction.
(Image: Meenesh Singh, et al.)
Engineers at the University of Illinois Chicago have built a machine that captures carbon from flue gas and converts it to ethylene.
The device integrates a carbon capture system with an ethylene conversation system for the first time. And, the system not only runs on electricity, but it also removes more carbon from the environment than it generates – making it what scientists call net-negative on carbon emissions.
Among manufactured chemicals worldwide, ethylene ranks third for carbon emissions after ammonia and cement.?Ethylene is used not only to create plastic products for the packaging, agricultural and automotive industries but also to produce chemicals used in antifreeze, medical sterilizers and vinyl siding for houses, for example.
The system and the results of the UIC College of Engineering scientists’ experiments are published in an Energy & Environmental Science paper titled “Fully-Integrated Electrochemical System that Captures CO2?from Flue Gas to Produce Value-Added Chemicals at Ambient Conditions.”
“This is the first demonstration of a net-negative, all-electric integrated system to capture carbon from pollutants and create a highly valuable resource,” said Meenesh Singh, UIC assistant professor in the department of chemical engineering.
“There is an urgent need to develop efficient technologies for integrated carbon capture and conversion to sustainably produce net-negative fuels. Currently, integrated carbon capture and conversion systems are highly energy-intensive and work in a discontinuous cycle of carbon dioxide capture and reduction. Efficiently integrating carbon capture with the conversion system eliminates the need for transportation and storage, and thereby increasing its energy efficiency.”
The integrated carbon capture and conversion system developed at UIC continuously captures carbon dioxide from flue gas to produce high-purity ethylene.
“This is an important milestone in ethylene decarbonization,” Singh said.
To capture carbon from the air or flue gas, Singh’s lab modified a standard artificial leaf system with inexpensive materials to include a water gradient — a dry side and a wet side — across an electrically charged membrane.
On the dry side, 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 CO2 conversion.
The system uses a modular, stackable design that allows the system to be easily scaled up and down.
To?convert captured carbon dioxide to ethylene, Singh and his colleagues used a second system in which an electric current is passed through a cell. Half of the cell is filled with carbon dioxide captured from a carbon capture system, the other half with a water-based solution. An electrified catalyst draws charged hydrogen atoms from the water molecules into the other half of the unit separated by a membrane, where they combine with charged carbon atoms from the carbon dioxide molecules to form ethylene.
The UIC researchers integrated the two systems by feeding the captured carbon dioxide solution to the carbon conversion system and recycling it back. The closed-loop recycling of solution ensures a constant supply of carbon dioxide from flue gas and its conversion to ethylene.
To test their integrated system, the researchers implemented a 100-square-centimeters bipolar membrane electrodialysis unit to capture carbon dioxide from the flue gas and hydraulically connected it to the 1-square-centimeter electrolysis cell to produce ethylene.
They were able to test the system continuously, 24 hours per day for seven days. The system was not only stable the entire time, it also captured carbon at a rate of 24 grams per day and produced ethylene at a rate of 188 milligrams per day.
“In the journey to make ethylene production green, this is a potential breakthrough,” Singh said. “Our next step is to scale up the integrated carbon capture and conversion system to produce ethylene at higher rates — a rate of 1 kilogram per day and capture carbon at a rate higher than kilograms per day.”
Original Article: An integrated, net-negative system captures carbon and produces ethylene
More from: University of Illinois at Chicago College of Engineering
The Latest Updates from Bing News
Go deeper with Bing News on:
Ethylene decarbonization
- Dow Inc. CEO promotes clean energy initiatives at Detroit Economic Club forum
Jim Fitterling, who heads the Midland-based company, touts "taking old technology and replacing it with the best available new technology." ...
- Lummus and Braskem to partner on electrified cracking heater for decarbonization
Lummus Technology, a global provider of process technologies and value-driven energy solutions, and Braskem, the largest bio-based polymer producer in the world, announced today the companies will ...
- Lummus and Braskem to Partner on Electrified Cracking Heater for Decarbonization
Demonstration and design to showcase the effectiveness of electrification technology and its sustainability benefits. "The selection of Lummus' SRT-e electric cracking heater as a means to ...
- Chemists stabilize ethylene on silver in search for better ethylene purification technology
However, ethylene production consumes massive amounts of energy; by some estimates, methods used to purify gases like ethylene are responsible for about 0.8% of the world's total carbon emissions.
- Chemical Plants Must Curb Ethylene Oxide, Chloroprene Emissions Under New EPA Rule
The Environmental Protection Agency on Tuesday issued a final rule on pollutants including ethylene oxide and chloroprene, affecting about 200 plants. The EPA said the rule, once in effect ...
Go deeper with Bing News on:
Green ethylene production
- Securing competitiveness of energy-intensive industries through relocation: The pulling power of renewables
Countries with limited potential for renewables could save up to 20% of costs for green steel and up to 40% for green chemicals from green hydrogen if they relocated their energy-intensive production ...
- Plastic-production emissions could triple to one-fifth of Earth’s carbon budget – report
Petrochemicals are then “cracked” into plastic building blocks such as ethylene – the aspect of plastic production with the largest emissions toll. Additional emissions come from the process ...
- Chemists stabilize ethylene on silver in search for better ethylene purification technology
However, ethylene production consumes massive amounts of energy; by some estimates, methods used to purify gases like ethylene are responsible for about 0.8% of the world's total carbon emissions.
- UTA chemists pioneer work to reduce carbon emissions
Production of ethylene is one of the most important chemical processes used today, with about 300 million metric tons of the tiny chemical produced each year. Ethylene gas is used to create ...
- Dow: Virtuous Growth Cycle Centered In North America
Dow's green tech initiatives, including a net-zero ethylene facility and recycling from food waste, have boosted its long-term growth potential. Facing macro headwinds, Dow has experienced a ...