Clean-tech company Ion Engineering has licensed carbon capture technology that provides a potentially cheaper and more efficient method for stripping greenhouse gases such as CO2 from industrial emissions, according to University of Alabama, which has patented the method.
Nearly all commercially available efforts at scrubbing GHGs from emissions use a liquid solution of water and amine, derived from ammonia, that contacts the stream, removing CO2 or other unwanted gases.
The new method, based on research by Dr. Jason E. Bara, assistant professor of chemical and biological engineering at UA, replaces much of the water in the aqueous amine solutions with a class of molecules called imidazoles, organic solvents with a low vapor pressure, or boiling point.
Bara says that imidazoles’ tunable chemical and physical properties give these solvents an advantage compared to other methods of carbon capture.
According to UA, the most common and most studied carbon capture method is introducing monoethanolamine, or MEA, into natural gas or post-combustion emissions, a process that can capture about 90 percent of CO2 from flue gas.
The use of MEA to scrub flue gas is energy intensive since recycling the solution requires boiling it to desorb the CO2 before recycle of the MEA solution back into contact with the flue gas. The cost of the energy needed to use MEA in power plants, for example, would likely be passed onto consumers, Bara says.
Bara’s work shows that swapping most of the water in the process with imidazoles saves energy since the solvent can be regenerated without the energy penalties associated with boiling large amounts of water. It also shows the solvent system can capture the same or more CO2 than MEA.
Bara helped found Ion Engineering and serves as a science adviser with the company.
The US Department of Energy, the National Science Foundation and the American Chemical Society Petroleum Research Fund funded Bara’s research.
In other carbon capture efforts, scientists in Australia are trialling a carbon capture system that turns emissions into green building materials, while a consortium led by VTT Technical Research Centre of Finland says it has created a more economical and ecological carbon capture system for use at power plants.