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Greenhouse Gases

Chemistry In Pictures

Chemistry in Pictures: Mechanical Trees

by Craig Bettenhausen
April 29, 2022


A stack of round fins rises out of a metal cylinder.
Credit: Arizona State

“Just plant trees,” critics of direct air carbon capture (DAC) say. Arizona State University engineering professor Klaus Lackner has a different idea: a DAC device he calls “Mechanical Trees .” Lackner and the team at Carbon Collect, a start-up licensing the tech from Arizona State, have been working on the chemistry and engineering of the system for several years. During Earth Week, he unveiled the prototype shown here in place at Arizona State. Carbon Collect says the device is up to a thousand times as efficient as trees at removing CO2 from ambient air. And unlike most DAC technologies, the system relies on wind to pass air over its CO2 sorbent blades, avoiding the energy cost and complexity of fans. When the sorbent is saturated, the blade assembly drops into the lower chamber, where heat and vacuum recover the CO2 for transport and storage, regenerating the sorbent. Carbon Collect expects to seek new investors toward the end of this year.

Credit: Carbon Collect

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