Enhancing CO₂ storage and marine carbon sink based on seawater mineral carbonation

Human activities emitting carbon dioxide (CO₂) have caused severe greenhouse effects and accelerated climate change, making carbon neutrality urgent. Seawater mineral carbonation technology offers a promising negative emission strategy. This work investigates current advancements in proposed seawater mineral carbonation technologies, including CO₂ storage and ocean chemical carbon sequestration. CO₂ storage technology relies on indirect mineral carbonation to fix CO₂, involving CO₂ dissolution, Ca/Mg extraction, and carbonate precipitation, optimized by adding alkaline substances or using electrochemical methods. Ocean chemical carbon sequestration uses natural seawater for direct mineral carbonation, enhanced by adding specific materials to promote carbonate precipitation and increase CO₂ absorption, thus enhancing marine carbon sinks. This study evaluates these technologies' advantages and challenges, including reaction rates, costs, and ecological impacts, and analyzes representative materials' carbon fixation potential. Literature indicates that seawater mineral carbonation can play a significant role in CO₂ storage and enhancing marine carbon sinks in the coming decades.