February 9, 2015
New sustainable carbon-capture technique uses baking soda
Chuck Bednar for redOrbit.com - Your Universe Online
Baking soda could help save the planet, according to a team of researchers from the Lawrence Livermore National Laboratory who have developed a way to use a solution of sodium carbonate to absorb carbon dioxide from coal or natural gas-fired power plants.The breakthrough, reported last week in the journal Nature, involves using a fluid made from the baking soda solution along with microcapsules that have permeable polymer shells to prevent the release of CO2, a greenhouse gas which contributes to global warming by trapping heat.
According to The Register, the new method is the first to feature controlled capture and release of carbon dioxide, and it can also be used by other industries, including steel and cement makers. The researchers said that using baking soda as the active chemical ingredient was essential to the success of their technique, which is kept in the capsule as CO2 passes through the shell.
“Our method is a huge improvement in terms of environmental impacts because we are able to use simple baking soda – present in every kitchen – as the active chemical,” Roger Aines, one of the LLNL team members involved in the research, explained in a statement. “Corrosiveness also is improved because the chemical is more benign and always is encapsulated.”
“Putting the carbonate solution inside of the capsules allows it to be used for CO2 capture without making direct contact with the surface of equipment in the power plant, as well as being able to move it between absorption and release towers easily, even when it absorbs so much CO2 that it solidifies,” he added.
Improving on the old
Aines, colleagues from the Livermore Lab, and experts from Harvard University and the University of Illinois at Urbana-Champaign said that they are looking to improve on current carbon capture methods, which are successful but can be harmful to the environment because they use caustic fluids, such as monoethanol amine to capture CO2.
Substances such as sodium carbonates are more environmentally friendly, they added. Unlike the more caustic substances used for capturing carbon dioxide, the newly-developed microcapsules react only with the specific gas of interest (CO2). The encapsulation method also drastically ups the absorption ability versus traditional carbon capture techniques, the study authors said.
This method will also prove to be a sustainable carbon capture process, not just because baking soda is easier to acquire and can also be repeatedly used, according to Tech Times. Substances used by previous methods had to be manufactured through a complex chemical process, and they tended to break down in a matter of months of years, the website added.
“It can be reused forever, while amines break down in a period of months to years,” said Aines. “We think the microcapsule technology provides a new way to make carbon capture efficient with fewer environmental issues. Capturing the world’s carbon emissions is a huge task. We need technology that can be applied to many kinds of carbon dioxide sources with the public’s full confidence in its safety and sustainability.”