Southwest Research Institute is leading an internally funded research project to evaluate an emerging method for reactive carbon capture, with the goal of reducing the steps involved in transforming carbon waste into useful industrial chemicals. The method uses deep eutectic solvents (DESs) that form a liquid at room temperature from two solids, taking advantage of the unique bonding properties of hydrogen molecules.
Photo Credit: Southwest Research Institute
Scientific Frontline: Extended "At a Glance" Summary: Reactive Carbon Capture via Deep Eutectic Solvents
The Core Concept: Reactive carbon capture utilizing deep eutectic solvents (DESs) is an emerging process designed to efficiently capture carbon waste and transform it into valuable commodity chemicals.
Key Distinction/Mechanism: To create a DES, a hydrogen-bond-accepting salt is mixed with a solid organic compound, such as urea or glycerol. This initiates hydrogen bonding, converting the solids into a room-temperature liquid. The highly tunable solvent captures carbon, which is then separated and reconfigured into useful byproducts via electrochemical reactions. This method functions as a green alternative, eliminating flammability hazards and minimizing the toxicity associated with traditional industrial solvents.
Origin/History: While DES applications for carbon capture were historically limited to academic research using pure carbon dioxide, Southwest Research Institute (SwRI) began bench-scale testing under real-world industrial conditions (accounting for chemical impurities) during fiscal year 2025.
Major Frameworks/Components:
- Deep Eutectic Solvents (DESs): Tunable fluid mixtures with lower melting points than their individual precursors.
- Hydrogen Bonding: The intermolecular attraction linking the chemical precursors to transition them from solid to liquid states.
- Electrochemical Pathways: The specific electrical and chemical reactions utilized to separate captured carbon into new configurations.
Branch of Science: Physical Chemistry, Electrochemistry, Materials Science, and Environmental Science.
Future Application: The commercial synthesis of valuable chemicals, including carbon monoxide, syngas, methanol, formate, and green hydrogen, directly supporting the manufacturing, energy, synthetic fuel, and agricultural industries.
Why It Matters: This technology presents a viable, scalable pathway to mitigate greenhouse gas emissions by transforming industrial carbon waste from an environmental liability into highly versatile, economically beneficial resources.
Southwest Research Institute is evaluating an emerging method for reactive carbon capture, a simplified process for turning carbon waste into value-added products. The method involves the use of deep eutectic solvents (DESs) that rely on hydrogen bonding, a natural phenomenon that links chemicals such as water, proteins, and DNA.
“Using this special class of solvent allows us to tap into complex hydrogen-bonding interactions,” said Miles Salas, a scientist at SwRI. “What’s truly exciting is the versatility. By playing with the ratio or composition of these DES mixtures, we can selectively tune them to achieve high performance in various applications. We can tune the reaction for separations, electrochemical pathways, or as green alternatives to traditional solvents widely used in manufacturing and other industries.”
To create a DES, scientists mix a hydrogen-bond-accepting salt component that conducts electricity with another solid ingredient, such as urea or glycerol. This forms hydrogen bonds that turn solids into a liquid at room temperature. When hydrogen bonding occurs, the molecules attract each other, almost magnetically. Once the ingredients are combined, scientists can use a variety of processes, such as electrochemical reactions, to separate the captured carbon into new configurations. The process can create a multitude of useful and valuable commercial chemicals, such as carbon monoxide, syngas, methanol, formate, or even green hydrogen. These byproducts can support manufacturing, energy, synthetic fuel, agriculture, and other industrial applications.
“We are evaluating these processes under real-world conditions, accounting for the various impurities seen in industrial settings. Up until this point, DESs for reactive carbon capture have been primarily explored using pure CO₂ and only in the context of academic research,” said Michael Hartmann, manager of SwRI’s Carbon Capture and Utilization Section. “Through research, modeling, and bench-scale testing, we are building the data needed to demonstrate this technology and its potential commercial viability.”
With lower melting points than their individual precursor components, DESs can eliminate flammability hazards and minimize toxicity concerns. Scientists can also modify the DES composition to meet various applications. SwRI scientists will first assess the capacity of various DES mixtures for performance. Then, the team will narrow down the most effective compositions and evaluate the best separation methods or electrochemical pathways for reactive carbon capture.
Additional information: Carbon Capture Utilization (CCU) Technology
Funding: This project was funded through SwRI’s Internal Research and Development program, which develops future-focused, unproven concepts to advance technology for government and industry clients. In fiscal year 2025, SwRI invested more than $13 million to fund new and continuing IR&D projects to pioneer new technologies, expand institutional knowledge and capabilities, and encourage the professional growth of its staff.
Source/Credit: Southwest Research Institute
Edited by: Scientific Frontline
Reference Number: chm091426_01