This study seeks to quantify NO_x sequestration by individual hydrated cementitious phases (C-S-H, AFm-SO₄, and Ca (OH)₂), establish a fundamental understanding of the reaction pathways, and reveal the effects of carbonation (CaCO₃ and AFm-CO₃). For uncarbonated phases, the highest NO_x uptake was measured in C-S-H, with the produced nitrite/nitrate physically bound on solid surface. For AFm-SO₄, an anion exchange process was observed, where nitrite/nitrate substitute for sulfate and form new AFm-NO₂/NO₃. Ca(OH)₂ showed undetectable NO_x uptake, which may be due to the relative low temperature and relative humidity. For carbonated phases, CaCO₃ exhibited an improved NO_x uptake compared to uncarbonated phases, with uptake capacity three times higher than that of C-S-H. The result of AFm-CO₃ indicates that carbonation could potentially inhibit the anion exchange process that was observed in AFm-SO₄. These findings provide guidelines for the rational design and optimization of cement-based materials for enhanced NO_x sequestration.

本研究旨在量化各个水合胶凝相（CSH、AFm-SO ₄和 Ca (OH) _{2 ）对 NO x}的封存，建立对反应途径的基本理解，并揭示碳化作用（CaCO ₃和 AFm- CO ₃ )。对于未碳酸化的相，在 CSH 中测量了最高的 NO _x吸收，产生的亚硝酸盐/硝酸盐物理结合在固体表面上。对于AFm-SO ₄，观察到阴离子交换过程，其中亚硝酸盐/硝酸盐取代硫酸盐并形成新的AFm-NO ₂ /NO ₃。Ca(OH) ₂显示检测不到 NO _x吸收，这可能是由于相对较低的温度和相对湿度。对于碳酸化相，与非碳酸化相相比，CaCO ₃表现出改进的 NO _x吸收，其吸收能力是 CSH 的三倍。AFm-CO ₃的结果表明，碳酸化可能会抑制在 AFm-SO ₄中观察到的阴离子交换过程。这些发现为合理设计和优化水泥基材料以增强 NOx 封存提供了_指导。