Extracting cement material made of seawater when carbon is captured

Concrete is the basic material in the modern world, with sand and cement actually among the smallest material production in the world by volume and weight.

Cement production is also a very energy -intensive activity. It is also exclusively on fossil fuels, which results in It is responsible for 8% of the world’s CO2 emissions in the production of cement.

It can be composed on emissions of CO2 cars and vans, Which are responsible for 10% of total emissions in the world. So, in order for the concrete to be more sustainable, it was as impressive as converting all the world’s EV cars and driving them only with green energy.

Many carbon emissions from this production come from mining, breaking, processing and refining raw materials used to produce it. Like lime, the rock -rich rocks are mined and mixed with clay to obtain a raw material that becomes concrete.

On Earth is potentially another source of calcium carbonate, which is sea water. Oceans contain many dissolved minerals, with race, table salt (sodium and chlorine ions), but also magnesium, calcium, potassium and even metals, with especially uranium, potential one -day source from the world’s instatead uranium mine. Dissolved CO2 in the form of carbonate ions is also abundant in the oceans, making them one of the strongest carbon sinks of the Earth.

Northwestern University and Cemex Innovation Holding AG (Switzerland) are now investigating whether to use this marine spitting horizon to create concrete raw material while capturing the Instatead CO2 to emit it. Have published their experience with results in advanced sustainable systems¹under the name “Electrodes minerals depicting carbon in seawater for variable electrochemical potentials and carbon dioxide injections“

Water electrolysis

Water (H2O) can be divided by its hydrogen and oxygen components by using a strong electric current, usually with some catalyst to improve the speed and efficiency of the electrochemical reaction. This is the basis of green hydrogen production, where electricity is a source of renewable sources.

However, when performing this procedure with unrealistic water and even more with seawater, the electrolytic reaction also responds with minerals dissolved in water.

This is generally undesirable reactions because it can create deposits on electrodes and take energy from the intended hydrogen production goal.

However, tuning the conditions of electrolysis could change this undesirable reaction of the by -product to a valuable new way of producing calcium carbonate.

Producing cement from seawater

Unlimited stock

This is not required a new idea, because the CACO3 and Seawaer magnesium have countless applications in the construction, production and environmental remediation of the industry, including the production of concrete, cement, paintings, paintings and girls.

Since the huge oceans covering the Earth would provide virtually unlimited supply of this material, this was considered to be the most unmarried potential source of these materials.

So far, just exploring the electrical medal of these minerals has not interfered a viable way to make its production from Economal Seawaer. This is where scientists at the Northwest University have brought a key next step: adding CO2 to the process.

CO2 injection into seawater

Becuse seawater is a complex mixture of many minerals when it brings electrolysis, suddenly there is an electrochemical network, from the clotting of calcium and magnesium to the formation of sulphate, generating chlorine and hydrogen gas as well

CO2 injection increases complexity because it reduces the pH of seawater. Reduction of PH from CO2 is partially compensated by the production of Olympic Games of electricity.

The dissolution or precipitation of calcium carbonate is in itself depending on the acidity of the water. For this reason, it is a phenomenon that concerns scientists because the atmosphere is richer in CO2, the oceans are more acidic.

If the electric current is powerful enough and therefore for the production of OH – ions can be sufficiently high to keep the pH above 8.5.

At the levels of acidity, they capture chemical reactions of CO2 and turn it into dissolved bicarbonate ions (HCO3-).

These bicarbonate ions then move in response to calcium and flow to the calcium carbonate, the basic material for concrete production.

Optimization of carbon sequestration

In this type of reaction, the production of calcium carbonate would be used for the cement industry by the injected CO2 institute of emitting CO2 into the atmosphere.

For any level of energy use, there is an optimal flow of CO2, which minimizes the energy consumed and at the same time maximizes the profit of the production of minerals. A concentration of 0.30 SCCM CO2 appaled so that there is such a sweet place where a lower power level still leads to a high weight of mineral precipitation.

Creating a usable deposit

The problem with the conversion of this concept into industrial application is the same problem that occurs when clotting calcium carbonate during hydrogen production through electrolysis.

More often than not, calcium storage clogs the surface of the electrode, damages the overall system and will be less efficient over time.

However, higher performance levels used in this experience, in combination with CO2 injections, caused further reactions, which caused the clot of calcium carbonate to contradict the electrode.

Overall, this method would be able to produce carbonate in a way that facilitates collection as a mineral bearing at the bottom of the tank without clogging the electrode.

Growing mineral crystals

Depending on the conditions, different mineral aggregates are formed with different crystal conditions, especially calcium carbonate (calcite and aragonite) and magnesium crystals.

Overall, the resulting material can be made of crystal several centimeters long (1-2 insert) and is also very porous.

The composition, porosity and size of aggregates synthesized by means of approval design meets the current standards for their use in materials such as concrete.

Conclusion

Overall, this publication proves that the production of cement material of the negative carbon is not only a theoretical option, but also a viable option when using carbon injection during marine taste electrolysis.

Critical parameters, such as hardness and abrasion resistance, should be examined to complete confirmation that the resulting material is applicable to construction projects.

This process is by its very nature scalable, without apparent restrictions on the rare availability of material, excessive energy consumption or low yields.

By enabling a network of interconnected and scalable reactors, this approach has the potential to be deployed on industrial steps and integrated into existing infrastructure such as coastal industrial facilities.

Further progress in the design of the reactor should be able to strengthen overall economic and energy efficiency, such as optimizing the geometry of electrodes, materials and flow dynamics.

In the end, the water from which the calcium was extra closer, perhaps also an interesting material for the secondary step of seawater hydrogen production, because the lower ion concentration should help reduce the problems associated with the electrode.

Investing in sustainable cement

Crah plc

As one of the leaders in the world in this production, CRH will be helpful in converting cement into a more sustainable industry. It is a total volume of building materials provided on American and European markets.

The company is active in 28 countries and 3.390 rental, employs 78,500 people, while CRH Americas earns 65% of its global sales.

The company expects robust western government expenditures in the field of infrastructure to help grow its business. Trends of re-industrial and sucking high-tech production should also help.

Sustainability

CRH has made serious progress in sustainability with a number of initiatives:

• It is a major recycling No. 1 in North America, with 43.9 million tonnes of waste and by -products from other industries recycled in 2023.
• In 2023, it reduced its CO2 emissions by 8%, thanks to the use of 36% of alternative fuels in its plants.
• It is love to reduce emissions by 30% by 2030 (compared to emissions 2021).

This is in itself commendable, but it can be considered too little, too late.

Fortunately, CRH is also the driving force of basic changes in this industry. Not only, Invested $ 75 million in a low -carbon cement company Sublime, along with a European particular giant Holcim.

Noble systems It was discarded from MIT in 2020 to use the electrolyzer to produce cement at surrounding temperatures, replace energy and fossil fuel-furnace furnaces. It also allows the use of calcium sources as input material and avoids the release of CO2 from the lime input.

Sublime FIRS-Commial Facility in Holyoke, Massachusetts is expected to be opened in 2026. If it is proven successful, it could be a real game changed for the cement industry, and it could open the way to scarate fellow citizens.

“Sublime is a disturbing force in this work. Its unique technology is going through the entire production process, from using pure electricity to raw without carbon. We are excited about its potential and we are pleased to work together to bring it to the market.

Officer Nollaig Forrest – the main sustainability of Holcima

CRH also invested in the next decarbonization and startups of sustainability:

• 23.7 million euros in Cool Planet Technologies technology, a developmental solution for carbon capture for industries that are traditionally difficult to decarbonized.
• $ 34.7 million from CRH and other investors UPCYCLING TechnologyThe use of all -electrical mineralization for permanent storage of CO2 in industrial by -products and minerals such as cement, plastics, consumer products, fertilizers and pharmacies.
• AICRETEThe “Recipe-As-A-Service” platform, which works with local concrete manufacturers, optimizes local materials and minimizes the cement used by AI analyzes, reducing both CO2 trace and concrete production costs.
• The B Fido AI is a startup using AI to reduce water consumption and increase water savings.

Overall, CRH is a profitable leader in a particular industry and is very actively preparing for decarbonization of this industry, both in existing facilities and by the main provider of capital for innovative startups that create the next generation of cement and specific production technology.

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Reference Study:

^{1. Devi, N., Gong, X., Shije, D., Wagner, A., Guerini, A., Zampini, D., Lopez, J., & Rotta Loria, AF (2025). Electrodes minerals for carbon capture in seawater for variable electrochemical potentials and carbon dioxide injections. Advanced sustainable systems, 9(3), 2400943. Https://doi.org/10.1002/adsu.202400943}