Frontier, a carbon removal consortium backed by the likes of Google and Meta, has signed a $11.7 million removal deal with carbon mineralization removal company 44.01.

The contract covers 20,932 tons of carbon, with credits expected to be delivered from 2028 to 2031.

London-based 44.01 removes carbon through a process called in-situ mineralization, which takes carbon captured via Direct Air Capture systems and industrial point sources such as cement factories. The company then mixes the captured CO₂ with water under optimized subsurface pressures and temperatures, causing it to dissolve into a carbonated fluid that it pumps roughly 1,000 meters (3,280 feet) deep, where it reacts with rocks to form stable solid carbonates.

The company will deliver the carbon from a project in the UAE, where it captures biogas from a wastewater treatment plant. According to the companies, the agreement seeks to establish whether the technique can operate at scale and over a longer time frame. Current projects have demonstrated the processes effectively on a shorter timescale.

“This first-of-a-kind agreement with Frontier marks an important step in taking in-situ mineralization from demonstration into commercialization,” said Talal Hasan, founder and CEO of 44.01, in the company announcement published by Frontier.

"Where we can store CO₂ shouldn't limit where we can remove it. In-situ mineralization could expand the storage map, making permanent storage practical in places conventional storage can't economically reach. That's why we're purchasing from 44.01: to prove out the technology and ready it for commercial scale," added Hannah Bebbington Valori, head of Frontier.

Frontier was launched in April 2022. Its founding members include Stripe, Alphabet, Meta, Shopify, and McKinsey Sustainability. In June, the consortium announced plans to invest a further $915m in carbon removal technologies, bringing its total commitment to $1.8 billion. Alongside the commitment, AI firm Anthropic joined the carbon buying alliance.

Recent carbon removal deals signed by the consortium include a $2m commitment to two zero-carbon lime companies, UK-based Leilac and Swedish firm SaltX, and two pre-purchase agreements totaling $3.05m with early-stage carbon removal firms, Pronoe and Cella.