This study investigated the effect of triethanolamine (TEA) on the hydration and carbonation of Class C fly ash (FA) varying its dosages (1 wt% and 5 wt%). From an early age, TEA enhanced the dissolution of calcium and alumina of FA, leading to improved hydration and carbonation. As a result, regardless of curing conditions, the reactivity of merwinite (C3MS2) and the formation of katoite (C3AH6) increased with TEA content. Furthermore, TEA remained in the pore solution for 7 days, affecting the hydration and carbonation products. Under wet curing, at 5 wt% of dosage, the complexation effect of TEA resulted in the preferential formation of ettringite over monosulfoaluminate, despite a high aluminate concentration. Meanwhile, under the carbonation curing in the presence of TEA, crystalline forms of calcium carbonate, as well as mono- or hemicarboaluminate, were not observed. Instead, spherical-shaped amorphous calcium carbonate was formed, with its quantity increasing with the TEA content, mineralizing CO2 up to 2.55 g per 100 g of FA. In addition, combining TEA and carbonation improved the formation of C-A-S-H, significantly enhancing the compressive strength. Consequently, the addition of TEA along with carbonation curing to FA resulted in a remarkable increase in mechanical performance and pore structure refinement. The carbonated FA pastes with 1 wt% and 5 wt% of TEA achieved the strengths of 44.8 MPa and 70.2 MPa, respectively, after 7 days.

中文翻译：

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通过添加三乙醇胺和 CO2 固化增强飞灰反应性


本研究调查了三乙醇胺 （TEA） 对改变其剂量 （1 wt% 和 5 wt%） 的 C 类飞灰 （FA） 的水化和碳酸化的影响。从很小的时候起，TEA 就增强了 FA 的钙和氧化铝的溶解，从而改善了水合作用和碳酸化。因此，无论固化条件如何，merwinite （C3MS2） 的反应性和 katoite （C3AH6） 的形成都随着 TEA 含量的增加而增加。此外，TEA 在孔隙溶液中停留了 7 天，影响了水合作用和碳酸化产物。在湿固化下，在 5 wt% 的剂量下，尽管铝酸盐浓度很高，但 TEA 的络合效应导致钙矾石的形成优于一磺基铝酸盐。同时，在 TEA 存在下碳酸化固化下，未观察到碳酸钙以及单碳铝酸盐或半碳铝酸盐的结晶形式。相反，形成了球形无定形碳酸钙，其数量随着 TEA 含量的增加而增加，每 100 g FA 中 CO2 矿化高达 2.55 g。此外，TEA 和碳化结合改善了 C-A-S-H 的形成，显著提高了抗压强度。因此，在 FA 中添加 TEA 以及碳化固化导致机械性能和孔隙结构细化的显着提高。TEA 含量为 1 wt% 和 5 wt% 的碳酸 FA 浆料在 7 天后分别达到 44.8 MPa 和 70.2 MPa 的强度。