Sucking up CO2

Founded: 2020

HQ: San Francisco, CA

When carbon and rocks become one.

Big Picture

Natural minerals are vital carbon sinks that have been balancing Earth’s carbon cycles for millennia. On geological timescales, CO2 in air and water chemically binds to minerals and permanently turns to stone. It is a highly efficient process, but one that takes a year or more in nature. In a future where we need to remove trillions of tons of CO2 from the atmosphere, speeding it up would be a big advantage.

How it Works

Heirloom automates carbon mineralization, cutting down the time required from years to weeks. Their closed-loop process first extracts CO2 from naturally abundant carbonates using electric kilns. Stripped of CO2, what remains of the carbonates moves through a passive air contactor, soaking CO2 back up from the ambient air. Once saturated, the carbonates cycle back through the kilns. Rinse and repeat.

Unfair Advantage

Their process is one of the most efficient CO2 removal processes you could engineer. Their primary feedstock is a widely available mineral that uses a chemical reaction to capture carbon. The result is a relatively low-capex, low-opex process that can verifiably extract carbon from the atmosphere while minimizing the land and energy required. At scale, it will enable a cost per ton of CO2 well below $100.


Gigaton of CO2e

potentially removed by 2035


Shashank was previously the co-founder and VP of Product at Tempo Automation.

Follow: @ShashankSamala


Noah is the co-inventor of Heirloom’s tech and a PhD candidate in Chemical Engineering at the University of Pennsylvania.

Follow: @NoahMcQueen13

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