Carbon dioxide mineralization – a promising pathway for permanent carbon removal

Reducing emissions remains essential, but it is no longer enough on its own. Meeting global climate goals will require both reducing new emissions and removing large amounts of carbon dioxide already in the atmosphere. For industries facing growing pressure to decarbonize, the ability to permanently remove carbon has implications for everything from regulatory compliance and investment decisions to project development and long-term competitiveness. 

This challenge is already reshaping how materials are produced, how infrastructure is built, and how companies meet their net-zero commitments. As governments tighten regulations and investors, customers, and communities increasingly demand measurable climate action, the question is becoming more urgent: once carbon dioxide is captured, what should be done with it?

Decarbonizing point-source emissions is critical to slowing the accumulation of greenhouse gases in the atmosphere and limiting the rise in global average temperatures, which are set to cross 1.5°C above pre-industrial levels. While significant progress has been made in adopting renewable energy and implementing green technologies that reduce fossil fuel use, it is clear that carbon capture utilization and storage (CCUS) will play an important role in hard-to-abate industries move toward net zero.

There are also trillions of tonnes of carbon dioxide already in the atmosphere from human activities. Addressing that legacy carbon will require carbon dioxide removal (CDR) approaches, including direct air capture (DAC) technologies. In all cases, carbon dioxide must be removed effectively, economically, safely, and most importantly, permanently.

Why storage matters as much as capture

Permanently removing carbon dioxide is not as simple as capturing it. Advances in CCUS and DAC technologies have made it increasingly effective and economical to produce concentrated streams of carbon dioxide from industrial emissions and the atmosphere. However, capturing carbon is only part of the challenge. Once it has been captured, where should it go?

If pure enough, it could be used for carbonated beverage manufacturing, although this typically delays emissions rather than removing carbon dioxide permanently. It can also be used as a feedstock for fuel manufacturing. While this is an important step away from fossil fuels, it is, at best, carbon neutral and, at worst, simply pushes emissions downstream.

Captured carbon dioxide can also be used for enhanced oil recovery in fossil fuel extraction wells. But it is challenging to quantify how much carbon dioxide is permanently sequestered through this method. Underground aquifers offer another storage option, but long-term storage can be hampered by geological uncertainty and the risk of surface release.

How carbon mineralization works

Carbon mineralization does something simple but powerful: it turns carbon dioxide into stable rock. The process mimics one of nature’s oldest forms of carbon storage, where ultramafic minerals, a group of magnesium-rich silicate minerals, react with atmospheric carbon dioxide over geological time periods to form carbonate rocks.

Technologies that remove carbon dioxide through mineralization accelerate these naturally occurring reactions in several ways. These include highly reactive magnesium and calcium oxides, elevated temperatures and pressures, improved particle morphologies (the shape and structure of particles), or catalytic ammonia and chloride-based solutions that help increase reaction rates.

What it will take to scale

Commercializing carbon mineralization at scale will depend on three practical enablers: supportive policies that reduce project risk, faster technology development that proves performance at scale, and trusted carbon credit or offset markets that create revenue for projects without a saleable product.

• Supportive policies – Government policies that recognize and incentivize carbon dioxide removal technologies can provide stability and reduce project implementation risk. Companies developing green cement products, for example, may need to navigate lengthy product approval processes before they can compete with traditional cement formulations. Streamlined regulations could reduce administrative delays and improve time-to-market. Governments could also support deployment through low-carbon procurement requirements for construction materials. As urbanization continues and cities become smarter and greener, such policies could create long-term demand and improve investor confidence.
• Accelerated technology development – Many CDR and DAC technologies are novel and have yet to be implemented at scale. A robust project development process is required to prove technical and economic viability and reduce risk. Scale-up and scale-out approaches must be carefully evaluated to determine the optimal configuration for large-scale commercialization.
• A trusted carbon credit/offset market – Technologies that remove carbon dioxide but do not generate a saleable product, such as river or ocean alkalinity enhancement or the activation of mine tailings, require carbon credits or offsets to generate revenue. While the carbon offset market has slowed since 2021 because many projects overstated their impact, carbon dioxide removal projects are far easier to verify than avoidance-based projects. Advances in monitoring, reporting, and verification systems are also contributing to increased investor confidence. Demand for carbon offsets remains robust, especially among blue-chip software, technology, and online retail companies that require offsets to achieve their net-zero ambitions.

Making carbon removal practical

Carbon helped power industrial progress. Now, managing its accumulation in the atmosphere is one of industry’s defining challenges. By turning captured carbon dioxide into stable minerals, carbon mineralization offers a pathway to make carbon removal more durable, measurable, and useful in long-term decarbonization strategies.

For organizations evaluating carbon removal pathways, the next step is to assess where mineralization could fit within their broader decarbonization strategy, including feedstock availability, project economics, verification requirements, and long-term storage objectives.