Direct CO₂ Capture by Alkali‐Dissolved Cellulose and Sequestration in Building Materials and Artificial Reef Structures

Abstract

Current carbon capture and utilization (CCU) technologies require high energy input and costly catalysts. Here, an effective pathway is offered that addresses climate action by atmospheric CO2 sequestration. Industrially relevant highly reactive alkali cellulose solutions are used as CO2 absorption media. The latter lead to mineralized cellulose materials (MCM) at a tailorable cellulose‐to‐mineral ratio, forming organic‐inorganic viscous systems (viscosity from 102 to 107 mPa s and storage modulus from 10 to 105 Pa). CO2 absorption and conversion into calcium carbonate and associated minerals translate to maximum absorption of 6.5 gCO2 gcellulose−1, tracking inversely with cellulose loading. Cellulose lean gels are easily converted into dry powders, shown as a functional component of ceramic glazes and cementitious composites. Meanwhile, cellulose‐rich gels are moldable and extrudable, yielding stone‐like structures tested as artificial substrates for coral reef restoration. Life Cycle Assessment (LCA) suggests new CCU opportunities for building materials, as demonstrated in underwater deployment for coral reef ecosystem restoration.

Exploring New Frontiers in Coral Nurseries: Leveraging 3D Printing Technology to Benefit Coral Growth and Survival

“…Mounting structures could be 3D-printed from gels or biodegradable materials that could dissolve over time, leaving the natural attachment of corals to either biomimetic substrates (Figure 6) or the reef itself. As some processes to 3DP settlement substrates and ARs may still produce carbon emissions, 3DP substrates for attaching coral fragments from materials such as cellulose could potentially uptake excess carbon at reef sites [58], leading to the hybridization of advanced biological substrates and coral mounting structures that could serve multifunctional purposes in coral reef restoration.…”

Additive Manufacturing in Underwater Applications

“…The first research made use of some tools, such as life cycle analysis, providing an example of work connected with the life cycle estimation of an underwater drone hull to study the Arctic [128]. Other analyses are connected with the environmental footprint, including estimations of the possible reduction of CO 2 emissions or its capture by using proper materials for artificial reef structures [129].…”

Direct-Air-Capture Technique of Cellulose for Mineralizing Pb2+ from Wastewater: Synchronous Accomplishment of CO2 Capture and Water Treatment

“…As the most abundant natural carbohydrate resource on earth, cellulose offers the advantages of low cost and easy availability, which makes it a suitable alternative for fossil materials. , Despite the fact that cellulose could form carbonates with CO 2 during the pulp-making process, − it has been a prevalent DAC material. − According to reports, , instead of CO 2 (due to a weak binding affinity), cellulose combines with a superbase such as NaOH or amine to improve its performance. Even though a superbase helps cellulose to attain DAC to some extent, adsorbed CO 2 appears in the form of soluble carbonates.…”