Mantel is a Cambridge, Massachusetts cleantech company building a molten-salt approach to industrial carbon capture. Spun out of MIT in 2022, its molten borate materials operate inside the high-temperature guts of boilers, kilns and furnaces, absorbing more than 95% of CO2 while recovering high-grade heat that offsets the energy cost of capture. The pitch is blunt: cut the cost of capturing a ton of carbon by more than half and make it work in the dirtiest, hottest corners of heavy industry - cement, steel, pulp and paper, power and refining.
Charm Industrial is a San Francisco-based climate company that converts agricultural residues into bio-oil through fast pyrolysis and injects it deep underground for permanent carbon removal. Founded in 2018 by Peter Reinhardt, Kevin Meissner, Shaun Meehan and Kelly Hering, Charm is one of the fastest-growing carbon dioxide removal companies and counts Frontier, Stripe, Microsoft, JPMorgan Chase, Meta and Shopify as customers.