Carbon-Negative Building Materials: Northwestern University's Seawater and CO2 Innovation

Researchers at Northwestern University, led by Nishu Devi and Alessandro Rotta Loria, have developed a novel method to create carbon-negative building materials using seawater and carbon dioxide. This innovative approach addresses global warming by capturing CO2 and transforming it into valuable construction components. The process involves applying a low electrical current to seawater, which splits water molecules into hydrogen gas and hydroxide ions. CO2 is then bubbled through the seawater, increasing bicarbonate ion concentration. These ions react with naturally occurring elements like calcium and magnesium to form solid minerals such as calcium carbonate and magnesium hydroxide. These minerals act as carbon sinks, effectively trapping CO2. The resulting material, with approximately half its weight comprised of carbon dioxide, can potentially replace sand in concrete, serving as a carbon storage solution. This sustainable alternative reduces the environmental impact of traditional concrete production, which contributes significantly to global CO2 emissions and relies on sand mining. This research, published in Advanced Sustainable Systems, offers a promising pathway towards greener construction practices.