热Ca2+/Mg2+交换反应合成CO2去除材料，这一成果由斯坦福大学Matthew W. Kanan研究团队经过不懈努力而取得。相关论文发表在2025年2月19日出版的《自然》杂志上。

在热化学条件下，CaCO₃和CaSO₄与多种富镁硅酸盐（如橄榄石、蛇纹石和奥辉石）定量反应生成Ca₂SiO₄和MgO。在潮湿条件下，Ca₂SiO₄暴露于环境空气中，在数周内转化为CaCO₃和硅酸，MgO部分转化为碳酸镁，而输入的硅酸镁在6个半月内没有反应性。或者，Ca₂SiO₄和MgO可以在数小时内在环境温度下吸收二氧化碳。使用CaCO₃作为Ca的存在，这种化学反应使CDR过程成为可能，其中输出的Ca₂SiO₄/MgO材料可以从空气或土壤中去除CO₂，并且CO₂过程排放被隔离。对能量需求的分析表明，这一过程所需的能量可能少于每吨二氧化碳去除的兆瓦时，大约是领先的直接空气捕获技术二氧化碳捕获能量的一半。这里描述的化学反应可以释放富镁硅酸盐作为安全和永久CDR的巨大阻力。

据了解，目前大多数碳管理战略都要求到2100年从大气中去除数千亿吨（Gt）的二氧化碳（CDR）。富含镁的硅酸盐矿物可以去除>10⁵Gt的二氧化碳，并将其作为稳定无害的碳酸盐矿物或溶解的碳酸氢根离子进行封存。然而，这些矿物在环境条件下的反应速度对于实际主题来说太慢了。

附：英文原文

Title: Thermal Ca²⁺/Mg²⁺ exchange reactions to synthesize CO₂ removal materials

Author: Chen, Yuxuan, Kanan, Matthew W.

Issue&Volume: 2025-02-19

Abstract: Most current strategies for carbon management require CO₂ removal (CDR) from the atmosphere on the multi-hundred gigatonne (Gt) scale by 2100. Mg-rich silicate minerals can remove >10⁵Gt CO2 and sequester it as stable and innocuous carbonate minerals or dissolved bicarbonate ions. However, the reaction rates of these minerals under ambient conditions are far too slow for practical use. Here we show that CaCO₃ and CaSO₄ react quantitatively with diverse Mg-rich silicates (for example, olivine, serpentine and augite) under thermochemical conditions to form Ca₂SiO₄ and MgO. On exposure to ambient air under wet conditions, Ca₂SiO₄ is converted to CaCO₃ and silicic acid, and MgO is partially converted into a Mg carbonate within weeks, whereas the input Mg silicate shows no reactivity over 6months. Alternatively, Ca₂SiO₄ and MgO can be completely carbonated to CaCO₃ and Mg(HCO₃)₂ under 1atm CO₂ at ambient temperature within hours. Using CaCO₃ as the Ca source, this chemistry enables a CDR process in which the output Ca₂SiO₄/MgO material is used to remove CO2 from air or soil and the CO₂ process emissions are sequestered. Analysis of the energy requirements indicates that this process could require less than 1MWh per tonne CO₂ removed, approximately half the energy of CO₂ capture with leading direct air capture technologies. The chemistry described here could unlock Mg-rich silicates as a vast resource for safe and permanent CDR.

DOI: 10.1038/s41586-024-08499-2

Source: https://www.nature.com/articles/s41586-024-08499-2