A recent study in Nature Energy reveals that this specialized reactor features a unique modular, three-chambered design, incorporating a meticulously engineered porous solid electrolyte layer at its core. According to Haotian Wang, a chemical and biomolecular engineer at Rice, this development marks a pivotal milestone in the quest to capture carbon from the atmosphere.

“Our research findings present an opportunity to make carbon capture more cost-effective and practically viable across a wide range of industries,” said Wang, the corresponding author of the study and associate professor of chemical and biomolecular engineering.

The device has achieved remarkable rates of carbon dioxide regeneration from carbon-containing solutions, making it a game-changer in industrial applications. Its performance metrics, including impressive long-term stability and versatility across various cathode and anode reactions, highlight its promising potential for large-scale industrial deployment.

“One of the major draws of this technology is its flexibility,” said Wang, explaining that it works with different chemistries and can be used to cogenerate hydrogen. “Hydrogen coproduction during direct air capture could translate into dramatically lower capital and operation costs for downstream manufacturing of net-zero fuels or chemicals.”

This innovative technology presents a compelling alternative to conventional high-temperature methods used in direct air capture. These traditional approaches often involve directing a mixed gas stream through high-pH liquids to extract carbon dioxide, an acidic gas.

The initial phase locks carbon and oxygen atoms in the gas molecules into new compounds within the liquid, creating bonds of varied strengths based on the trapping chemicals employed. The critical next step involves retrieving carbon dioxide from these solutions, achievable through heat, chemical reactions, or electrochemical methods.

Zhiwei Fang, a postdoctoral researcher at Rice and co-first author of the study, pointed out that existing direct air capture technologies typically rely on high-temperature processes to regenerate carbon dioxide from the sorbent, the agent that filters out carbon dioxide.

“Our work focused on using electrical energy instead of thermal energy to regenerate carbon dioxide,” Fang said, adding that the approach has several additional benefits, including working at room temperature, not needing additional chemicals, and generating no unwanted byproducts.

The chemicals utilized for capturing carbon dioxide each have unique benefits and drawbacks. Among them, amine-based sorbents are the most prevalent choice because they form weaker bonds, requiring less energy to release the carbon dioxide.

However, their high toxicity and instability are notable concerns. In contrast, water-based solutions like sodium hydroxide and potassium hydroxide present a more environmentally friendly alternative, although they demand significantly higher temperatures for effective carbon dioxide release.

“Our reactor can efficiently split carbonate and bicarbonate solutions, producing alkaline absorbent in one chamber and high-purity carbon dioxide in a separate chamber,” said Wang. “Our innovative approach optimizes electrical inputs to efficiently control ion movement and mass transfer, reducing energy barriers.”

According to TechXplorist