Capture6 is a Direct Air Capture (DAC) company that generates carbon dioxide removal (CDR) to sell in the Voluntary Carbon Market (VCM). The company developed an electrochemical process that produces sodium hydroxide (NaOH) from brines and then uses its aqueous form as a sorbent for their Direct Air Capture (DAC). The process results in the mineralization of CO2 in the form of sodium carbonate (Na2CO3). To correctly source NaOH, the company looks to partner and integrate with water treatment facilities, using reverse osmosis to concentrate the facilities’ brine output. Electrodialysis then separates the NaOH from Sodium Chloride (NaCl) within the brine. As a benefit from this process, an extra 50% of the brine can be recovered as fresh water.

Their process utilizes a flexible core technology which can produce multiple different outputs depending on site resources, notably salt content in the brine. Today they stand at a TRL 6.

• Project Monarch (California): At Palmdale Water District’s Pure Water Antelope Valley Demonstration Facility, Capture6 will install a fully integrated water management and carbon dioxide (CO₂) removal facility. This pilot will have a capacity of 100 tonnes of CO2 removal per year, breaking ground in 2024. After the pilot, their designed roadmap includes building a commercial facility and subsequent large scale facility.

• Project Octopus (South Korea): In partnership with K-water and BKT/Tomorrow Water, Capture6 is developing an integrated facility for water recovery and carbon removal at a seawater desalination plant. This will be a two phase deployment that aims to develop a large-scale commercial facility (500 ktpa). Phase 1 will be a pilot of 1000 tpa to be deployed in late 2024.

• Project Wallaby (Australia): In partnership with Pilot Energy Limited, Capture6 is assessing the integration of Capture6’s joint water production and direct air capture (DAC) technology into the Mid West Clean Energy Project (MWCEP), Pilot’s clean ammonia export project, which aims to produce up to 1.2 million tonnes per year.

• Capture6 raised $6.3 million in a seed round in January 2023 and an undisclosed non-equity assistance from the Carbon to Value Initiative (C2V Initiative)

• Capture6 was awarded a grant from the California Energy Commission under the Commercialization Industrial Decarbonization (CID) Program. The grant that is aimed at supporting Project Monarch is valued at over $8M – the largest sum awarded in the round.

• December, 2023: Respira International has announced its plan to buy up to 50,000 carbon removal credits from Capture6.

Capture6 is a technology developer, developping partnerships to build and operate their facilities across a global pipeline. Capture6 is pursuing multiple partnership models simultaneously, including but not limited to liscencing, CDR offset revenues and equity agreeements.

Capture6 combines existing water treatment solutions with their proprietary technology to capture CO2 from the air. This innovation allows them to recover fresh water for residential, agricultural and industrial use, while permanently sequestering atmospheric CO2 as carbonates. At the end of Capture6’s process, these carbonates can be permanently and durably stored underground or in the ocean with ocean alkalinity enhancement (OAE). Storage underground involves sealing the carbonates in inactive mines, where, mineralized carbonates remain stable on timescales of 10,000 to 100,000 years, in the absence of major disturbances such as extreme seismic activity, acute flooding, etc.

Capture6 is pursuing several branches of engineering and science research to further expand the efficiencies of their process. This focus on innovation allows Capture6's projects to align with additional industrial verticals and create multiple co-benefits at each project’s location.

Capture6's DAC technology is specially designed to be integrated with water treatment and desalination facilities, as they use alkaline compounds easily extractable from brines for their process. This allows them to co-locate and increase water processing efficiency while also providing extra benefits for plant owners and the local communities in the form of surplus available clean water.

Possible water sources include:

• geothermal brines
• seawater
• desalination brine
• saline / brackish groundwaters
• industrial wastewater

Capture6's process results in the production of carbonates which can then be used for Ocean Alkalinity Enhancement (OAE) applications, a rapidly evolving carbon removal method.

Other end uses / deposits of the carbonates include:

• storage at abandoned mine sites / geological sequestration
• concrete aggregate